Abstract:
A vacuum cleaner attachment is disclosed having a concave vacuum head with a swivel joint that permits swiveling of the vacuum head only within the plane of the vacuum head. The concave vacuum head can have a curvature that is similar to the curvature of a cylindrical surface to be vacuumed. Thus, while a user manipulates the conduit providing the air suction to the vacuum head, the concave surface can be supported and swiveled around the circumference of the cylindrical surface to be vacuumed, while the vacuum head is also moved along the length of the cylindrical surface. Throughout this movement of the concave vacuum head, the concave opening of the concave vacuum head can stay in closer proximity and conformity to the cylindrical surface than is possible using a fixed vacuum head with a flat opening, thereby making cleaning of the cylindrical surface more effective and efficient.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application is based on the provisional application Ser. No. 62/289,392 filed Feb. 1, 2016, the entire contents of which is herein incorporated by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates generally to vacuum cleaner attachments, and more particularly to vacuum cleaner attachments having a concave vacuum head. 
       BACKGROUND OF THE INVENTION 
       [0003]    Many attachments for vacuum cleaners have a flat opening for cleaning the many flat surfaces commonly found in homes and offices. A different situation exists when the surface to be vacuumed is cylindrical or otherwise curved. In such cases, the flat opening fails to get sufficient simultaneous proximity and conformity to the curved surface of the cylinder (e.g., a log, a pipe, a round post), substantially reducing the ability of the attachment to use suction to clean the surface. 
         [0004]    Recently, it was estimated that there are over 450,000 log homes in the United States, with more being built each year. Many have at least some interior walls with exposed log surfaces. It can be very difficult to keep these exposed log surfaces clean and dust free using vacuum attachments with flat openings for at least the aforementioned reason. 
         [0005]    Aside from using a vacuum cleaner, other existing cleaning methods fall short of providing satisfactory removal of dust and other debris from the log surfaces. For example, a brush on an extension pole does little more than move the dust from the logs to the furnishings or floors below. Dust rags and cloths catch on the rough surfaces of exposed logs, leaving rag particles behind that create a mess on the log rather than removing the dust. 
       SUMMARY OF THE INVENTION 
       [0006]    A general aspect of the invention is an apparatus for attachment to a vacuum cleaner. The apparatus includes: a vacuum head, the vacuum head including a concave opening having a concave curvature corresponding to a convex curvature of a cylindrical surface to be vacuumed; and an attachment mechanism configured to support the vacuum head and configured to provide suction generated by the vacuum cleaner to the vacuum head. 
         [0007]    In some embodiments, the cylindrical surface that is to be vacuumed is one of: a log, a pipe, a post, a beam. 
         [0008]    In some embodiments, the attachment mechanism includes a swivel joint that swivels only within a central plane of the vacuum head. 
         [0009]    In some embodiments, the attachment mechanism includes a swivel joint that includes a bendable hose for providing suction to the vacuum head in any swivel position. 
         [0010]    In some embodiments, the vacuum head includes a plurality of bristles disposed at the concave opening of the vacuum head. In further embodiments, the plurality of bristles are disposed at acute angles with respect to the concave opening of the vacuum head. In other further embodiments, the plurality of bristles are disposed at an angle of about 45° with respect to the concave opening of the vacuum head. 
         [0011]    In some embodiments, the concave opening has a curvature corresponding to a convex surface with a cylindrical curvature having a radius between approximately 6 inches and approximately 12 inches. 
         [0012]    Another general aspect of the invention is an apparatus for attachment to a vacuum cleaner, this apparatus including: a vacuum head including a concave opening having a curvature that generally corresponds to the convex curvature of a surface to be vacuumed, the vacuum head being symmetrical about a central plane that bisects the vacuum head; a swivel joint having a first section in fixed engagement with the vacuum head, and a second section that is in swivelable relationship with the first section, the swivel joint being configured to swivel only through the central plane of the vacuum head; and a flexible conduit extending from the first section to the second section, the flexible conduit being configured to provide suction generated by the vacuum cleaner to the vacuum head. 
         [0013]    In some embodiments, the first section includes a neck extending therefrom for connection to a further conduit. 
         [0014]    In some embodiments, the first section of the swivel joint includes a sphere having an annular opening for supporting an end of the conduit, the sphere further having an arcuate passageway; and the second section of the swivel joint includes a carriage mounted for swiveling within the sphere, wherein the neck is in fixed alignment for swiveling with the carriage, and wherein the neck extends through the arcuate passageway and is movable with the carriage as the carriage swivels with respect to the sphere. 
         [0015]    In some embodiments, the carriage includes a rail, and the sphere includes a track configured to engage the rail, wherein movement of the rail along the track allows the carriage to rotate within the sphere. 
         [0016]    In some embodiments, the carriage includes at least two rails disposed at opposite sides of the neck, wherein the sphere includes at least two tracks respectively engaging the at least two rails, and wherein movement of the at least two rails along the at least two tracks allows the carriage to swivel within the sphere. 
         [0017]    In some embodiments, the sphere includes: a first hemisphere fixed to the vacuum head, the first hemisphere including the annular opening; and a second hemisphere fixed to the first hemisphere, the second hemisphere including the arcuate passageway. 
         [0018]    In some embodiments, the first and second hemispheres include overlapping peripheral edges. 
         [0019]    In some embodiments, the vacuum head includes a plurality of bristles disposed at the concave opening of the vacuum head. In further embodiments, the plurality of bristles are disposed at acute angles with respect to the concave opening of the vacuum head. In still further embodiments, the plurality of bristles are disposed at an angle of about 45° with respect to the concave opening of the vacuum head. 
         [0020]    In some embodiments, the concave surface has a curvature corresponding to a convex surface of a log having a radius of between approximately 6 inches and approximately 12 inches. 
         [0021]    Another general aspect of the invention is an apparatus for attachment to a vacuum cleaner, this apparatus including: a vacuum head including a concave opening having a curvature generally corresponding to a convex curvature of a surface to be vacuumed; a sphere including a first hemisphere fixed to the vacuum head, and a second hemisphere fixed to the first hemisphere, the first hemisphere having an annular opening, the second hemisphere having an arcuate passageway, attachment of the first and second hemispheres forming a track along an interior surface of the sphere; a carriage having a neck configured to extend through the arcuate passageway, the carriage including a rail configured to engage the track so as to allow the carriage to swivel within the sphere, and to allow the neck to move along the arcuate passageway; and a conduit extending between the annular opening of the first hemisphere and the neck so as to provide fluid communication of suction between the vacuum head and the vacuum cleaner. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The invention will be more fully understood by reference to the detailed description in conjunction with the following figures. 
           [0023]      FIG. 1  is a side view of an embodiment of a vacuum system including a vacuum cleaner attachment for cleaning cylindrical surfaces, such as a log. 
           [0024]      FIG. 2  is a top perspective view of the embodiment of the vacuum cleaner attachment of  FIG. 1 . 
           [0025]      FIG. 3  is a bottom perspective view of the embodiment of the vacuum cleaner attachment of  FIG. 1 . 
           [0026]      FIG. 4  is an edge-on perspective view of the embodiment of the vacuum cleaner attachment of  FIG. 1 . 
           [0027]      FIG. 5  is a partial cut-away side view of one embodiment of the vacuum cleaner attachment where a neck of the vacuum cleaner attachment is swiveled within the central plane of the vacuum head into perpendicular relationship with a longitudinal axis of the vacuum head. 
           [0028]      FIG. 6  is a partial cut-away side view of the embodiment of  FIG. 5  where the neck of the vacuum cleaner attachment is swiveled within the central plane of the vacuum head to make an acute angle with respect to the longitudinal axis of the vacuum head. 
           [0029]      FIG. 7  is a partial cut away side view of the embodiment of the  FIG. 5  where the neck of the vacuum cleaner attachment is swiveled within the central plane of the vacuum head to become substantially parallel to the longitudinal axis of the vacuum head. 
           [0030]      FIG. 8  is a perspective view of an embodiment of a mounting member that can be used in an embodiment a swivel joint, where the mounting member is in the form of a hollow sphere having spherical interior surfaces. 
           [0031]      FIG. 9  is a partial cut-away view of one embodiment of the swivel joint showing a carriage mounted for swiveling within the hollow sphere of  FIG. 8 . 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0032]      FIG. 1  shows one embodiment of a vacuum system including a vacuum cleaner attachment  10  having a concave opening  50  for cleaning a cylindrical surface  20 . For this example, it is assumed that the cylindrical surface  20  is an exterior surface of a log  30 , such as one used in building a log cabin. 
         [0033]    As shown, the vacuum cleaner attachment  10  includes a vacuum head  40  having a concave opening  50 . The concave contour of the concave opening  50  corresponds to the cylindrical contour of surface  20  of the log  30 . Common building logs have a radius of between approximately 6 inches to approximately 12 inches. The concave contour of the concave opening  50  of the particular vacuum head  40  can be chosen to accommodate curved objects having various other radii. There may be situations in which a single convex contour of the vacuum head  40  can effectively accommodate a range of different cylindrical surface radii. Alternatively, a user may elect to employ different vacuum heads, each different vacuum head having an opening with a concave contour radius that matches the radius of the cylindrical surface to be cleaned. 
         [0034]    The vacuum head  40  may include a plurality of bristles disposed at the concave opening  50  to adapt to a range of cylindrical radii. The bristles  60  at a first portion  70  of the concave opening  50  may advantageously extend at an acute angle of about 45° in a first direction, while the bristles  60  at a second portion  80  of the concave opening  50  may extend at an acute angle of about 45° in a second direction. The bristles  60  proximate to a third portion  90  of the concave opening  50  may, for example, extend generally perpendicular to the surface. 
         [0035]    The vacuum head  40  of the vacuum cleaner attachment  10  may include an attachment mechanism  100  that supports the vacuum head  40 . The attachment mechanism  100  is configured to provide one or more fluid flow channels between one or more components connected to a vacuum cleaner and one or more vacuum openings at the concave opening  50 . Here, the outlet  110  of the attachment mechanism  100  is attached to the vacuum cleaner through a flexible hose  120  and rigid pole  130 . Other components, however, may be used in addition to, or in lieu of, those shown in  FIG. 1 . 
         [0036]    In one example, the attachment mechanism  100  may include a swivel joint, shown generally at  140  of  FIG. 1 . The swivel joint  140  may be configured to generally limit swiveling of the vacuum head to a single central plane, such as the central plane defined by the central seam  170  (see  FIGS. 2 and 3 ). When the concave opening  50  has an arc length less than the arc length of the convex surface of, for example, a log, the vacuum head is easily swiveled to various angles about the circumference of the log. In this manner, the concave opening  50  is maintained in close proximity and conformity to the cylindrical surface of the log as the vacuum head is swiveled around the circumference of the log, while the vacuum head is moved along the length of the log. Various views of the vacuum head  40  and swivel joint  140  are shown in  FIGS. 2-4 , where the bristles  60  are not shown to enhance clarity. 
         [0037]    Referring to  FIG. 2 , the vacuum head  40  includes a first shell  150  and a second shell  160 . The first and second shells  150  and  160  are joined with one another along the central seam  170 , and support various components of the swivel joint  140 . An upper portion of the vacuum head  40  is open and defines an arcuate slot  180 , which allows a neck of the swivel joint  140  to move through the central plane defined by the central seam  170  about a rotation axis  200  in the direction shown by arrows  210 . 
         [0038]      FIG. 3  is a bottom perspective view of the vacuum cleaner attachment  10 . In this view, a conduit  220 , in the form of a rigid elbow, is connected to a flange  230  of the neck  190 . The bottom portion of the swivel joint  140  includes an inlet  240  that opens to a vacuum chamber  250 . The bottom portion of the vacuum chamber  250 , in turn, has lower edges defined by the concave opening  50 .  FIG. 3  also shows another view of the seam  170  joining the first and second shells  150  and  160 . 
         [0039]      FIG. 4  is bottom perspective view of the vacuum cleaner attachment  10  with the conduit  220  attached to the neck  190 . In this embodiment, a conduit  260 , shown here as a flexible tube, provides fluid communication for suction between the inlet  240  of the swivel joint  140  and an inlet  270  of the neck  190 . 
         [0040]      FIGS. 5-7  show the neck  190  at various positions as it swivels through various positions along the arcuate slot  180  in the direction shown by arrow  275 . Here, the arcuate passageway  370  is coplanar with the longitudinal axis  280  of the vacuum head  40  so that any swivel movement of the neck  190  is generally limited to lie within that plane. 
         [0041]      FIGS. 5-7  show a central axis  277  of the neck  190  that is coplanar with the longitudinal axis  280  and the central plane defined by the central seam  170 . In  FIG. 5 , the central axis  277  is approximately perpendicular to the longitudinal axis  280 . In  FIG. 6 , the neck  190  has been swiveled to a position at which the central axis  277  is at an angle  290  with respect to the longitudinal axis  280  and in the same plane as the central axis  277 . In  FIG. 7 , the neck  190  has been swiveled to an orientation at which the central axis  277  is approximately parallel to the longitudinal axis  280  and in the same plane as the central axis  277  and the central plane defined by the central seam  170 . The neck  190  may also be swiveled in the direction of arrow  300  ( FIG. 5 ) to positions at which the central axis  277  lies at various angles with respect to the longitudinal axis  280 . Since the conduit  260  is flexible, the neck  190  and vacuum head  40  may be rotated with respect one another without substantially inhibiting the suction needed to clean the surface being vacuumed. 
         [0042]    Rotation of the neck  190  with respect to the longitudinal axis  280  allows the user to engage rounded surfaces of convex objects, such as logs, at various angles. This makes it easier to vacuum surfaces such as those found on logs that are stacked on one another in a log home. Further, in instances in which the concave opening of the vacuum head has an arc length less than half of the circumference of the surface of the log, the vacuum head can be swiveled to vacuum most of the circumference of the log, while maintaining the concave opening in close proximity and conformity to the convex cylindrical surface of the log while the vacuum head is also moved along the length of the log. 
         [0043]    In one embodiment, the swivel joint  140  includes a carriage mounted for rotational movement within a mounting member having a spherical interior surface. For ease of manufacture, the exterior of the mounting member may also be spherical. Although the term “sphere” is used with reference to the mounting member, it is to be understood that the term also applies to any shaped mounting member in which the interior surfaces are spherical.  FIG. 8  shows one example of such a sphere  310 , where the sphere  130  is substantially hollow so that it is light-weight and limits the amount of material needed to manufacture it.  FIG. 9  is a partial cut away view of the swivel joint  140  showing one example of a carriage  320  mounted for swiveling within the sphere  310 . 
         [0044]    Referring to  FIG. 8 , the sphere  310  may include a first hemisphere  330  fixed to the vacuum head  40 . The first hemisphere  330  may be fixed to the vacuum head  40  using, for example, fasteners extending through openings  340 . The sphere  310  also may also include a second hemisphere  350  that is fixed to the first hemisphere  330  using, for example, one or more fasteners extending through the bores  360 . The second hemisphere  350  includes an arcuate passageway  370 . In some examples, the arcuate passageway  370  may extend into the first hemisphere  330 . In other examples, the arcuate passageway  370  may be coextensive with the arcuate slot  180  of the housing  40 . 
         [0045]    Referring to  FIG. 9 , the carriage  320  includes a pair of annular rails  380  attached to opposite sides of the neck  190 . Each rail  380  engages a corresponding circular track  390  formed at the interior walls of the sphere  310 . During operation, the rails  380  of the carriage  320  are guided along the corresponding circular tracks  390  to allow rotation of the carriage  320  within the sphere  310 . When the sphere  310  is fixed with the vacuum head  40 , the neck  190  and any corresponding attachments, may rotate with respect to one another in the manner shown and described in connection with  FIGS. 5-7 . 
         [0046]    It will be appreciated that the foregoing disclosure provides examples of at least one example of the various manners that may be used to implement the present invention. However, it is contemplated that other implementations of the invention may differ in detail from the foregoing examples. All references to the invention or examples thereof are intended to reference the particular example being discussed at that point and are not intended to imply any limitation on the scope of the invention more generally. All language of distinction and disparagement regarding certain features is intended to indicate a lack of preference for those features, but not to exclude such from the scope of the invention entirely unless otherwise indicated.