Patent Publication Number: US-2005115018-A1

Title: Bendable extension pipe for vacuum cleaner

Description:
BACKGROUND OF THE INVENTION  
      1. Field of the Invention  
      The present invention relates generally to a vacuum cleaner and in particular to a bendable extension pipe for a vacuum cleaner, the bendable extension pipe having a joint foldably connected to the vacuum cleaner, thereby permitting convenient cleaning of spaces under pieces of furniture, such as bed or sofa.  
      2. Description of the Background Art  
      In general, a vacuum cleaner draws in contaminants on a surface to be cleaned which are entrained in air drawn in to the vacuum cleaner with the aid of a vacuum suction force generated by a vacuum suction motor provided in a cleaner body. Generally, a flow passage is formed so as to connect the cleaner body and a suction brush used for performing the cleaning operation in and airtight connection.  
      Such a flow passage may be variously provided depending on the types of vacuum cleaners being used. For example, a canister vacuum cleaner is provided with a flexible hose connecting a cleaner body and a manipulation handle, and an extension pipe is provided for connecting the manipulation handle and the suction brush. Such an extension pipe may be provided as an extendible type that can be adjusted in length, as required, or as a combination type that comprises a plurality of segmented extension tubes capable of being individually disassembled or assembled for use depending on the desired length of the pipe.  
      However, in the case of a suction brush connected by a conventional extension pipe, the angle between the extension tube and the suction brush is typically fixed, that is, having a straight connection between the segments of the extension pipe. Therefore, in order to clean areas under furniture, such as a bed, sofa, etc., it is necessary for a user to perform the cleaning operation while rotating the extension pipe after lowering his/her posture and orienting the suction brush so it is in close contact with the floor surface. In addition, even if the angle between the extension pipe and the suction brush is adjustable, inconvenience results in that the user must lower his/her body in order to insert the suction brush into an area under the furniture. An improved system for cleaning under furniture is demanded.  
     SUMMARY OF THE INVENTION  
      Accordingly, the present invention has been conceived to solve the above-mentioned problems occurring in the conventional vacuum cleaners, and an aspect of the present invention is to provide a bendable extension pipe for a vacuum cleaner having an improved construction that permits a user to conveniently perform cleaning operations by simple manipulation of a button without needing to bend the body or lower his or her posture.  
      In order to achieve the above aspect according to the present invention, a bendable extension pipe for a vacuum cleaner comprises first and second extension pipe sections connected so that they can be selectively bent with respect to one another in a bent configuration, and a release handle that releases the bent configuration of the first and second extension pipe sections when a user depresses the release handle. For smoother operation, it is preferable that the connection joint between the first and second extension pipe sections is enclosed by an articulated cover, and a resilient member is provided within the articulated cover to resiliently support the release handle.  
      According to a first embodiment of the present invention, the first extension pipe section comprises: a tubular body, a cylindrical joint formed at an end of the tubular body and connected to the second extension pipe section to thereby form the joint connection, and hinge projections formed on the body to project outwardly from a surface thereof so provide a mount for the release handle.  
      The cylindrical joint may have an axis of rotation intersecting a virtual axis of the flow passage formed in the tubular body in a perpendicular orientation.  
      The hinge projections preferably comprise a pair of cylindrical projections formed on opposite sides of the tubular body to project coaxially outwardly from the surface of the tubular body, and the release handle preferably comprises hinge slots providing for a sliding interference fit onto one of the cylindrical hinge projections so that the release handle covers at least a part of the circumference of the first extension pipe section, wherein each hinge slot comprises a slot opening end that opens outwardly from the release handle and a closed end. The closed end is preferably formed to correspond to the diameter of the corresponding hinge projection, and a bottleneck is preferably formed between the opening end and the closed end so as to prevent the hinge projections from breaking away from the hinge slots.  
      The lever may be formed integral with the release handle.  
      The articulated cover may comprise one or more seat projections on which an elastic member is seated, and a guide ridge having a stepped part, the tip end of the lever being engaged with the stepped part, in which the tip end of the lever is supported by any of the seat projections, thereby restraining the folding angle between the first and second extension pipe sections. In addition, it is also preferable that the guide ridge is projectedly formed on the inner surface of the articulated cover in a form of spiral track and the elastic member is formed from a leaf spring. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The above described and other aspects, features and advantages of the present invention will be more apparent from an understanding of the following detailed description taken with reference to the accompanying drawings, in which:  
       FIG. 1  is a perspective view of a bendable extension pipe for a vacuum cleaner according to the present invention;  
       FIG. 2  is an exploded perspective view of the bendable extension pipe for a vacuum cleaner according to the present invention;  
       FIG. 3  is a detailed, perspective view showing the bendable extension pipe for a vacuum cleaner according to the present invention with a closure cover removed; and  
       FIGS. 4 and 5  are partially cut-away side views showing the initial state and the folded state, respectively, of the bendable extension pipe for a vacuum cleaner according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS  
      Hereinbelow, a bendable extension pipe for a vacuum cleaner according to the present invention will be described in detail with reference to the accompanying drawings.  
      As shown in  FIGS. 1 and 2 , a bendable extension pipe  100  comprises a first extension pipe section  110 , a second extension pipe section  120 , a release handle  130 , and an articulated cover  140 .  
      The first extension pipe section  110  comprises a tubular body  111 , a cylindrical joint  112  formed at one end of the body  111 , for providing a joint connection of tubular body  111  to the second extension pipe section  120 , and hinge projections  113  formed on the body  111  to project outwardly from a surface so as to provide an installation mount for the release handle.  
      The cylindrical joint  112  is preferably arranged in such a way that its axis, shown as broken line A in  FIG. 2 , perpendicularly intersects the virtual central axis, shown as broken line B, of a flow passage formed within the body  111 . Protrusions  112   a  are formed substantially at the centers of the opposite lateral sides to project outwardly therefrom, so as to be in engaging contact with the inner peripheries of guide ridges  143  (see  FIG. 3 ) as will be described below.  
      The hinge projections  113  are formed on the opposite sides of the body  111 , preferably as a pair of coaxial cylindrical projections, to extend laterally from the surface of body  111 .  
      The second extension pipe section  120  is connected at a distal end to a suction brush (not shown) that draws in dirt and dust from a surface to be cleaned, and the second pipe section  120  is pivotably joined to the first extension tube  110  at a proximal end of the second extension pipe  120 . A joint section  121 , connected to the cylindrical joint  112 , is formed having a complementary shape to cover the circumferential surface of the cylindrical joint  112 . The joint section  121  allows the second extension pipe section  120  o be freely pivotable and the second extension pipe section  120  serves to prevent the loss f suction force despite folding of the joint connection between the extension pipe sections.  
      The release handle  130  is attached by a hinge to the first extension pipe  110  and has a semicylindrical shape so as to enclose a part of the circumferential surface of the first extension pipe  110 . In addition, as shown in  FIG. 2 , the release handle  130  preferably comprises projected levers  131 , which more preferably are integrally formed with the body of the release handle  130 , and hinge recesses  134 , each having a recess opening  132  provided to face outwardly along axial edges of the release handle  130 . Each of the recesses  132  may slidingly fit onto and around one corresponding hinge projection  113  and a closed end  133  of each recess opening end  132  being configured to engage a corresponding hinge projection  113 . The closed end  133  is formed in such a way that its inner periphery corresponds to the diameter of the corresponding hinge projection  113 , thereby providing an interference fit therebetween. Meanwhile, each hinge recess  134  preferably has a bottleneck part h disposed between the recess opening  132  and the closed end  133  for providing the interference fit.  
      In the embodiment illustrated in  FIGS. 2 and 3 , the levers  131  are formed integrally with the release handle  130 . However, the invention is not limited to this arrangement and it is possible to form the levers as separate members and to connect them to the release handle  130  using an appropriate means. However, in order to reduce the processing steps during manufacturing and to easily manufacture the levers, it is preferable that they are produced in an integrally formed mold together with the release handle  130 , as shown.  
      The articulated cover  140  serves to close a connection part J (see  FIG. 2 ) formed by joining the cylindrical joint  112  and the joint section  121  and is provided with oppositely disposed left and right articulated cover parts  140   a ,  140   b . In addition, as shown in  FIG. 3 , the inner side of each articulated cover part  140   a ,  140   b  comprises at least one seat projection  141  on which a resilient member S is seated, and the guide ridge  143  having a discontinuous stepped part  142 , which the tip end  131   a  of a corresponding one of the levers  131  engages.  
      The guide ridge  143  is formed to project from the inner side of the articulated cover  140  and preferably has the form of a slightly spiral track. Therefore, it is preferable that the stepped part  142  is formed at the junction area of the starting point and ending point of the spiral track of the guide ridge  143 , as shown in  FIG. 3 , and one of the end points face the tip end  131  a of the corresponding lever  131  at the basic or normal position of the corresponding lever  131 . In the basic position, the first and second extension pipe sections  110 ,  120  are aligned in a straight relationship with respect to each other.  
      Hereinbelow, operation of the preferred embodiment of the present invention is described with reference to  FIGS. 4 and 5 .  
      As shown in the drawings, in a bendable extension pipe  100  for a vacuum cleaner according to the present invention, a first extension pipe section  110  is connected to the cleaner body (not shown) and a second extension pipe section  120  is connected to a suction brush (not shown), which draws in air and entrained dirt and dust from a surface to be cleaned. The first and second extension pipe sections  110 ,  120  are arranged to be foldable relative to a joint connecting one to the other, so a folded or bent configuration may be effected, according to user&#39;s selection, and as shown in  FIG. 5 .  
      That is, the user may wish to utilize the bendable extension pipe  100  in the bent position, so that the suction brush, to which the pipe  100  is connected, can be in closest contact with a surface to be cleaned, such as when it is desired to clean a floor surface below a bed or a piece of furniture. The user then grasps the release handle  130  that covers the first extension pipe section  110  and exerts a downward force in the direction indicated by the arrow in  FIG. 4 .  
      When the user grasps and depresses the release handle  130 , a lever  131 , preferably formed integrally with the release handle  130 , is pivoted along with the release handle  130 , so that pivoting the release handle  130  about the hinge projections  113  causes the end  131   a  of lever  131  to break away from engagement with the stepped part  142  formed on an inner side of an articulated cover  140 . At that time, the elastic member S provided in the articulated cover  140  applies resilient restoring force to the lever  131 , so that the lever  131  that has broken away from engagement with the stepped part  142  makes face-to-face contact with the guide ridge  141  and pivot along the guide ridge  141 .  
      The seat projection  141  preferably comprises first to third pairs of seat projections  141   a,    141   b,    141   c,  ( FIG. 3 ), within which the elastic member S is installed. The third seat projection  141   c  is formed to be projected at a position for blocking the movement of the tip end  131   a  as it slides along the guide ridge  143 , thereby restraining the further rotational movement of the lever  131 . Accordingly, when the user grasps and depresses the release handle, the first and second extension pipe sections  110 ,  120 , that are initially aligned in a straight line, rotate relative to each other until the tip ends of the levers  131  come into contact with the third seat projections  141   c.  Preferably, the folding angle between the first and second extension pipe sections is retained at about 45 degrees, but an angle of between 40 and 50 degrees is considered appropriate.  
      In order to return the first and second extension pipe sections to their initial position of being aligned in a straight line, where the folding angle between the extension pipe sections is zero degrees, the user may grasp the first extension pipe section  110  and lift up the second extension pipe section  120  connected to the suction brush (not shown), without requiring any operation or separate instrument. The second extension pipe  120  is forced to pivot about the connection joint as a result of its own weight and the weight of the suction brush (not shown), which are forced downwardly by gravity. As the relationship between the extension pipe sections reach a straight line orientation, the lever  131  engages and becomes seated on the stepped part  142  while being compressed by the elastic member S, so that the first and second extension pipe sections return to the initial straight-line orientation and are fixed thereto by the engagement of the tip end  131   a  with stepped part  142 . Therefore, it is possible to avoid the user&#39;s inconvenience of having to operate a separate button or lever so as to unbend the folded extension pipe to the original straight line orientation.  
      As described above, according to the inventive bendable extension tube for a vacuum cleaner, since the user can provide for a bend in the extension pipe with a simple operation of a lever depression, without needing to bend his or her body or become lower in posture, it is possible to conveniently clean an area below a piece of furniture, such as a bed or sofa. In addition, since it is possible to return the extension pipe from the bent orientation to its initial straight line orientation merely by lifting the extension pipe, the user&#39;s convenience can be enhanced.  
      While the embodiments of the present invention have been shown and described with reference to the preferred embodiments thereof in order to exemplify the principle of the present invention, the present invention is not limited to the above described and illustrated embodiments. It will be understood that various modifications and changes can be made by those skilled in the art without departing from the spirit and scope of the invention. Therefore, it shall be considered that such modifications, changes and equivalents thereof are all included within the scope of the present invention as defined by the appended claims.