Abstract:
An exhaust system for a vacuum cleaner where filtered air is directed outside the main body of the vacuum cleaner through exhaust holes formed in at least one of a plurality of supporting wheels rotatably mounted to both sides of the main body. The disclosed exhaust system provides an improved aesthetic appearance in a structurally efficient design.

Description:
This application is the national phase under 35 U.S.C. § 371 of PCT International Application No. PCT/KR00/00215, which has an International filing date of Mar. 15, 2000, which designated the United States of America 
   TECHNICAL FIELD 
   The present invention relates to a vacuum cleaner, and more particularly, to a device for exhausting air from inside a vacuum cleaner to the exterior thereof. 
   BACKGROUND ART 
   Generally, a vacuum cleaner generates a suction force for picking up dirt and debris, such as dusts and other particulate matter. The suction force is created by a flow of air between an intake port and exhaust port and that travels through the interior of the vacuum cleaner. 
   Referring to  FIGS. 1 and 2 , the vacuum cleaner  1  creates a suction force by generating a continuous air flow through various constituent parts of the vacuum. The vacuum cleaner  1  uses an electric motor to create an air flow that is directed toward an exhaust port resulting in a pressure drop on the intake side of the motor. This pressure drop creates a suction force, or an air flow, at the intake port that is used to pick up dirt and debris. Dirt and debris suspended in the air flow are carried into the vacuum and pass through a filter or filters as the air flow is exhausted into the atmosphere. 
   The vacuum cleaner  1  includes a main body  10 . A fan  13 , rotated by a driving force of a motor, is mounted inside the main body  10  for creating the air flow described above. The intake side of the vacuum includes a suction nozzle  20  connected to the main body  10  by a suction hose  31 , a grip portion  32 , and an extension pipe  33 . These elements are sequentially connected between the suction nozzle  20  and the main body  10  for guiding the air flow with foreign matters drawn through the suction nozzle  20  into the main body  10 . 
   The air which is drawn to inside of the main body  10  of the vacuum cleaner  1  passes through dust collecting bag  11  that filters the dirt and debris from the air as it migrates through the vacuum. Once filtered, air is then exhausted through a plurality of exhaust holes  14  formed at rear of the main body  10 . An air exhaust filter  15  is mounted at an inner part of the main body  10  across the plurality of exhaust holes  14  to collect fine dusts contained in the air exhausted through each of the plurality of exhaust holes  14 . 
   To promote ease of movement, the main body  10  has a plurality of wheels  16  that are rotatably mounted on both sides of the main body  10 . The mounting structure of each of the wheels  16  is shown in  FIGS. 3 and 4 . Each of the wheels  16  is connected to the main body  10  using a combination of supporting elements. As shown in the drawings, each of the plurality of wheels  16  include a hook  16   a , formed near the center rotational axis of the wheel  16 , and a projected locking portion  10   a , for mounting the hook  16   a  thereto, that is formed at the outer surface of the main body  10 . 
   However in conventional vacuum cleaners, the aforementioned wheels  16  are merely used for the sole purpose of facilitating the easy movement of the main body  10 , and do not have any other functions. 
   Additionally, the air exhaust filter  15  must be frequently replaced with a clean filter to ensure that dirt and debris trapped in the filter does not impede air flow created by the vacuum. In a conventional vacuum, it was quite cumbersome for a user to replace the air exhaust filter which requires the user, in some systems, to disassemble the entire vacuum cleaner for replacing the air exhaust filter. 
   Further, while the functions and designs of a vacuum cleaner have been recently improved, the aesthetic appearance has not. In particular, the plurality of exhaust holes  14  formed at rear of the main body  10  are visually unappealing because of user perception that the air inside the vacuum cleaner is exhausted thereto. 
   SUMMARY OF THE INVENTION 
   Accordingly, the present invention is directed to an exhaust system in a vacuum cleaner that substantially obviates one or more of the problems due to limitations and disadvantages of the related art. 
   An object of the present invention is to provide a device for exhausting air from a vacuum cleaner in which an air exhaust filter can be easily replaced. 
   Another object of the present invention is to provide a device for exhausting air from a vacuum cleaner with a visually appealing aesthetic appearance that masks the exhaust holes by incorporating them into other structural features of the vacuum. 
   Additional features and advantages of the invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings. 
   To achieve these and other advantages and in accordance with the purpose of the present invention, as embodied and broadly described, the device for exhausting air from a vacuum cleaner includes a main body for suction and collecting of various contaminants, wheels rotatably mounted at both sides of the main body, an exhaust flow passage formed between the main body and the wheels for discharging the filtered air from the main body, and an air exhaust filter provided at the exhaust flow port for filtering dirt and debris. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention: 
     In the drawings: 
       FIG. 1  is a perspective view of a conventional vacuum cleaner; 
       FIG. 2  is a cross-sectional view showing the interior of a conventional vacuum cleaner; 
       FIG. 3  is a disassembled perspective view showing a structure for mounting a wheel to the main body of a conventional vacuum cleaner; 
       FIG. 4  is a cross-sectional view showing a wheel and the structure for mounting a wheel to a conventional vacuum cleaner of  FIG. 3  connected to a main body of a vacuum; 
       FIG. 5  is a disassembled perspective view showing an exhaust device for a vacuum cleaner in accordance with a first embodiment of the present invention; 
       FIG. 6  is a cross-sectional view of the exhaust device of  FIG. 5  with a wheel mounted to the main body of a vacuum in accordance with a first embodiment of the present invention; 
       FIG. 7  is a disassembled perspective view showing an exhaust device for a vacuum cleaner in accordance with a second embodiment of the present invention; 
       FIG. 8  is a cross-sectional view of the exhaust device of  FIG. 7  with a wheel mounted to the main body of a vacuum in accordance with a second embodiment of the present invention; 
       FIG. 9  is a disassembled perspective view showing a main part of a variation of a grip portion in accordance with the second embodiment of the present invention; 
       FIG. 10  is a disassembled perspective view showing an exhaust device for a vacuum cleaner in accordance with a third embodiment of the present invention; 
       FIG. 11  is a cross-sectional view showing each component of  FIG. 10  in an assembled state in accordance with a third embodiment of the present invention; 
       FIG. 12  is a disassembled perspective view showing a main part of a variation of a grip portion in accordance with the third embodiment of the present invention; 
       FIG. 13  is a disassembled perspective view showing an exhaust device for a vacuum cleaner in accordance with a fourth embodiment of the present invention; and 
       FIG. 14  is a cross-sectional view showing each component of  FIG. 13  in an assembled state in accordance with a fourth embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. 
     FIG. 5  is a disassembled perspective view showing an exhaust device for a vacuum cleaner in accordance with a first embodiment of the present invention that includes an exhaust device that combines a wheel with an exhaust filter. 
   While only one wheel  160  is shown and described with respect to the first preferred embodiment, a second conventional wheel is disposed on the opposing side of the main body  100 . 
   A guiding projection  102  is formed about an exhaust hole  101  in the outer surface of the main body  100 . The guiding projection  102  is circular shaped and surrounds a plurality of exhaust holes  101  formed in the main body  100 . While the exhaust holes  101  are shown as being arcuate shaped, other hole configurations may be equally as effective in promoting air flow. The guiding projection includes a supporting rim that projects from the main body  100  for receiving and for supporting elements of the wheel  160 . 
   The wheel  160  includes a guiding member  162  for housing an air exhaust filter  161  and for supporting rolling movement of a rolling member  163 . The guiding member  162  includes a rim that projects from a circular member. The rim of the guiding member  162  has a diameter that permits a portion of the rim to securely fit within the rim of the guiding projection  102  that together support rotating movement of the rolling member  163 . 
   The guiding member  162  includes a rib  162   a  that projects from the center of the rim to its inner surface. The rib  162   a  defines a plurality of openings that promote air flow through the wheel  160  when engaged with the guiding projection  102  and main housing. The rib  162   a  of the guiding member also assists in securely holding the air exhaust filter  161  to prevent detachment and shaking. 
   The air exhaust filter  161  has a circular shape that fits in a holding chamber defined by the combination of the guiding member  162  and guiding projection  102 . 
   The rolling member  163  has a plurality of projections  163   a  along an inner circumference thereof that enable it to slide around the supporting structure. The rolling member  163  is preferably made of a soft pliable material, such as rubber, for smooth contact and rolling on a variety of surfaces, such as carpet, hardwood flooring or linoleum. However, the rolling member  163  may also be formed of other comparatively lesser soft materials such as plastic and metal. 
   The wheel is held together by a system that also holds the filter between the guiding projection  102  and the guiding member  162 . The locking hole  102   a  formed in the rim of the guiding projection  102  receives the protrusion  162   b , formed in an outer circumference of the rim of guiding member  162 . At the same time, the hook  162   c  of the guiding member  162  engages a corresponding locking hole  102   a  of the guiding projection  102 , so that the wheel  160  and the main body  100  are connected with each other in a locked condition. 
   The protrusion  162   b  and hook  162   c  are preferably formed along the circumference of the guiding member  162  for maintaining a secure connection between the main body  100  and the wheel  160 , and at the same time, for providing a mechanism for easily detaching the wheel  160  from the main body  100  when necessary. 
   The disclosed wheel  160  functions as an exhaust port to promote the free flow of air from the dust collecting bag to outside the main body  100  that replaces the exhaust holes formed at the rear of the main body  100  of a conventional vacuum cleaner. 
     FIG. 6  is a sectional view showing the main parts of a wheel  160  connected to the main body  100  in accordance with a first embodiment of the present invention. 
   As shown in  FIG. 6 , the air exhausting filter  161  is fixed between an outer surface of the main body  100 , in which the exhaust holes  101  are formed, and the guiding member  162 . The guiding member  162  is being connected to the guiding projection  102  formed at the main body  100  to be fixed thereto by cooperative engagement of the protrusion  162   b  and hook  162   c  with the guiding projection  102  and locking hole  102   a . The rolling member  163  is rotatably connected to an outer circumference of the guiding member  162  when connected with the guiding projection  102 . 
   The operation of the first embodiment of the present invention will be explained in detail. 
   First, a motor rotates a fan creating an air flow on the backside of the fan that results in air flow on the intake side of the vacuum, i.e. a suction force. Air and dusts pass through the suction nozzle  20 , the extension pipe  33 , the grip portion  32  and the suction hose  31 , to be drawn into the dust collecting bag  11  provided within the main body  100 . Then, once filtered air passes the dust collecting bag  11  and flows inside the main body  100 , the air flowing inside the main body is exhausted to outside of the main body  100  through the plurality of exhaust holes formed at one side of the main body  100  through the wheel  160 . Accordingly, air is filtered a second time as it passes through exhaust filter  161  housed within the wheel  160 . 
   When replacing the air exhaust filter  161  with a new one, the guiding member  162  connected to the guiding projection  102  of the main body  100  is simply detached thereby providing easy access to air exhaust filter  161 . 
   A second preferred embodiment will now be described with reference to  FIGS. 7 and 8  that shows an exhaust device in accordance with a second embodiment of the present invention having a structure that allows the air exhaust filter  161  to be easily mounted and replaced. With the exception of the structure described below, other parts in the structure are the same as those of the first embodiment. 
   As shown in  FIG. 7 , a projected center axis  103  is integrally formed at a side of the main body  100  surrounded by a plurality of exhaust holes  101 . The projected center axis is formed to penetrate corresponding apertures in both the air exhaust filter  161  and the guiding member  162  of the wheel  160 . A grip portion  164  is mounted at an outer side of the guiding member  162  of the wheel  160  for connecting to the center axis  103  to fix the guiding member  162  to the guiding projection  102 . 
   In the aforementioned structure, the grip portion  164  replaces the locking mechanism described in the first embodiment. The protrusion  162   b  and the hook  162   c  formed at the outer circumference of the guiding member  162 , and the locking hole  102   a  which was formed at the outer circumference of the guiding projection  102  are not necessary in accordance with the second embodiment of the present invention. That is, an end portion of the center axis  103  which is projected outwardly of the guiding member  162  is formed as a cylindrical shape having an empty space therein, and locking portions  103   a  are integrally formed along an inner circumference facing each other, to be projected inwardly of the center axis. 
   A connecting axis  164   a  which is inserted inside of the center axis  103  is formed at the grip portion  164 . The connecting axis  164   a  is provided with locking protrusions  164   b  which engage the locking portion  103   a  of the center axis  103  when the connecting axis  164   a  is inserted into the center axis  103  for preventing detachment thereof. The combined structure provides a secure and easily accessible mechanism for mounting the air exhaust filter  161  within the wheel  160 . 
   Each locking protrusion  164   b  of the grip portion  164  has an inclined surface whose width narrows toward a rear of the grip portion  164 . That is, when the locking protrusion  164   b  is located within the locking portion  103  and the grip portion  164  is rotated, the locking portion  103   a  passes the inclined surface of the locking protrusion  164   b  and is located at an inner portion thereof, thereby guiding the grip portion  164  to be completely inserted inside the center axis  103 . Since a gap between the locking protrusion  164   b  and a packing member  165  is narrower than the thickness of the locking portion  103   a , the locking portion  103   a  is compressed between the locking protrusion and the packing member  165 . 
   A projected rotation preventing portion  103   c  is additionally formed axially at one end of the locking portion  103   a , for limiting the rotation range of the grip portion  164 . 
   A packing member  165  is positioned on the connecting axis  164   a , between an inner wall of the guiding member  162  and the locking protrusion  164   b  of the grip portion  164  for sealing a gap there between. The packing member  165  is preferably formed of a comparatively flexible material, for sealing the gap at its maximum. 
   The procedure of mounting the air exhaust filter having the aforementioned structure in accordance with the second embodiment of the present invention will be explained in detail. 
   First, the center axis  103  penetrates the air exhaust filter  161  as it projects from an inner part of the guiding projection  102  at a side of the main body  100 . The guiding member  162  is mounted on the center axis  103  and moves against the guiding projection  162  to form a chamber for holding the air exhaust filter  161 . The air exhaust filter  161  can be easily mounted since hole  161   a  is formed at the center of the air exhaust filter  161  for easy alignment with the center axis  103 . 
   The connecting axis  164   a  of the grip portion  164  is then inserted into the center axis  103  which is exposed through the center portion of the guiding member  162 , and the grip portion  164  is rotated to complete the connection. That is, when the grip portion  164  is rotated, the locking portion  103   a  formed at the center axis  103  passes the inclined surface of the locking protrusion  164   b  formed around the connecting axis  164   a  of the grip portion  164 , and is gradually moved to an inner part of the locking protrusion  164   b  to be closer to a inner surface of the guiding member  162 . 
   The packing member  165  mounted between the locking protrusion  164   b  and the guiding member  162  is gradually compressed to seal the space there between and produce a force to secure the connection of the locking protrusion  164   b  and the guiding member  162 . When in this position, the fixing force of the packing member  165  prevents further rotation of the grip portion  164 . 
   Continuous rotation of the grip portion  164  causes the locking protrusion  164   a  to engage the rotation prevention portion  103   c  formed at the inner wall of the center axis  103  placing the wheel  160  in a locked condition. 
   A variation of the grip portion of the second embodiment is shown in  FIG. 9 . As shown there, a projected, substantially A shaped grip portion protrusion  164   c  is formed on an exterior surface of the guiding member  162  to assist a user in firmly gripping the grip portion protrusion  164   c . The shape of the grip portion protrusion  164   c  is not limited to have the aforementioned shape, but can be formed in other shapes to promote a secure grip such as a “+” or an “I” shape. 
   A third preferred embodiment will now be described with reference to  FIGS. 10 and 11  that show a connecting relationship between the center axis formed at a side of the main body  100  and a separate grip portion. 
   The structure of the third embodiment is similar to that of the second embodiment, except with respect to the connecting relationship between the center axis and the grip portion. That is, a plurality of screw threads  103   b  are formed along an inner circumference of an aperture in the center axis  103  that is designed to receive a projected connecting axis  164   a  having corresponding screw threads  164   d  formed along its outer circumference is formed in the grip portion  164 , thereby enabling easy mounting of the air exhaust filter  161 . 
   The procedure of mounting the air exhaust filter  161  in accordance with the third embodiment of the present invention will be explained in detail. 
   First, the air exhaust filter  161  is mounted on the center axis  103 , and the guiding member  162  is mounted against the outer circumference of the air exhaust filter  161 . The hole  161   a  is formed at the center of the air exhaust filter  161  to receive the center axis  103  allowing the air exhaust filter  161  is be easily mounted as described above. 
   The connecting axis  164   a  of the grip portion  164  is then inserted into the center axis  103  which is exposed through the center portion of the guiding member, and the grip portion  164  is rotated to complete the connection by causing the corresponding screw threats to pull the constituent elements together in a secured relationship. 
   A projected, substantially Λ shaped grip portion protrusion  164   c  is formed on an exposed surface of the grip portion to promote a more secure grip by the user. The grip portion protrusion  164   c  is not limited to have the aforementioned shape, but can be formed in other shapes such as a “+” or an “I” shape. 
     FIG. 12  shows a modified version of the third preferred embodiment where the grip portion  164  is integrally formed as part of the guiding member  162 . 
   The air exhaust filter  161  may be easily removed from the wheel  160  by rotating the grip portion  164  out of engagement with the center axis. Once the guiding member  162  is separated from the center axis  103 , the air exhaust filter  161  may be removed. 
   With the aforementioned embodiments, the exhaust holes  101  are integrally formed as part of the main body  100 . However, a situation may occur where the exhaust holes become blocked with debris. For example, fine dusts passing through each of the exhaust holes  101  of the main body  100  may collect in the exhaust holes as a result of moisture that passes through the vacuum or that is introduced from the outside. When this occurs, a user must wipe or clean the entire side portion of the main body  100  to remove the contaminants thereof. Further, it may be difficult or impossible to fully clean the exhaust holes from the exterior of the main body  100  without potentially exposing internal circuitry and systems of the vacuum to water or other cleaning solutions. 
     FIGS. 13 and 14  show a fourth embodiment of the present invention to solve the aforementioned problem. 
   The fourth embodiment in accordance with the present invention includes an exhaust system in which a side portion of the main body  100  is completely open without exhaust holes. A guiding projection  202  has an outer circumference that projects from the main body  100  and around an opening in the main body  100 . A portion of the guiding projection supports the rolling member  163 . A separate filter assembly  200 , having an air exhaust filter  210 , is mounted between the guiding projection  202  and guiding member  230  to form the wheel. 
   The filter assembly  200  is securely fixed to the main body  100  of the vacuum cleaner. In the illustrated embodiment, a bolt is used. However, securing devices may also be used. 
   The filter assembly  200  includes center axis  220  which penetrates and supports the air exhaust filter  210 . A guiding member  230  for supporting the air exhaust filter  210  is mounted at the center axis  220  to prevent detachment of the air exhaust filter  210 . When assembled, the guiding member  230  is moved against the filter assembly  200  using the grip portion  164  in a manner as described with respect to the aforementioned embodiments. Rotation prevention portions  231  are used for compressing the outer part of the air exhaust filter  210 . 
   The air exhaust filter  210  in the filter assembly  200  can be replaced without disassembling the filter assembly  200 . 
   Meanwhile, while the exhaust system of the present invention is characterized as having a wheel construction with guiding projection and guiding member, other variations of the wheel and supporting structure are possible that do not depart from the spirit and scope of the invention. 
   For example, a plurality of exhaust holes may be provided at each side of the main body and an air exhaust filter may be provided between the exhaust holes and the wheel. 
   Further, while the preferred embodiments of the exhaust system use only one wheel located on one side of the main body as an exhaust passage, multiple wheels that define multiple exhaust passages may be used. In these variations, the exhaust passage may include one or multiple wheels with filters that may be used together or in various combinations. For example, in one system, the user may sequentially use multiple wheel passages one at a time. As the filters in each wheel become blocked with debris, the blocked wheel is deactivated and a new wheel opened. This enables the user to use the vacuum even if the initial filter becomes inoperable.