Abstract:
A curved handle for a manually operated implement has a straight segment extending from a first curved segment having a uniform radius of curvature and a second curved segment having a different uniform radius of curvature extending from the first segment. The handle has two working ends and a threaded connection on each end for securing various working attachments or members. This multi-use handle can thus be used in implements performing numerous different applications on horizontal, vertical and elevated surfaces.

Description:
BACKGROUND OF THE INVENTION 
   The present invention relates to curved handles for manually operated implements such as mops, brooms, paint applicators, reach rods, and a variety of other handheld tools. The invention provides a handle which is not only ergonomically shaped for maximum efficiency, but is also configured to allow cleaning members and other working elements to be attached to either end of the handle for effective use in different cleaning and other functional modes. 
   Most implement handles are substantially straight in design and, as a result, so are the majority of brooms, mops, applicators and other implements employing elongated handles. Over the years, handles have been provided which contain some degree of curvature, as exemplified by U.S. Pat. Nos. 6,203,626, 6,487,747, U.S. Des. Pat. Nos. D413,234, and 433,890, or more drastic curved configurations which are purportedly designed to enhance appearance or provide the user with an ergonomic advantage, e.g. U.S. Pat. Nos. 2,753,579 and 5,791,006. However, many of these prior art handles do not accomplish the results claimed for the variety of potential users. In addition, such handles are often difficult to manufacture and they are cumbersome when it comes to storage of the implements. Existing handles also do not provide the option of connecting different working attachments at both ends of the handle for efficient and ergonomic use in different use positions. 
   SUMMARY OF THE INVENTION 
   It is thus the object of the present invention to provide a curved handle for a manually operated implement which overcomes the disadvantages and limitations of prior products. 
   It is an object of the present invention to provide a curved handle for a manually operated implement which permits the connection of different attachments to either working end of the handle, to allow efficient, effective, and ergonomic use of the implement in different working modes. 
   It is a further object of the present invention to provide a curved handle for a manually operated implement which is highly efficient in use regardless of which end of the handle has a working attachment secured thereto. 
   It is still another object of the present invention to provide a curved handle for a manually operated implement which is easy to manufacture and convenient to store. 
   It is another object of the present invention to provide a curved handle for a manually operated implement which has two working ends and, as a result, has the flexibility to be used both on horizontal, vertical and elevated surfaces. 
   It is a further object of the present invention to provide a curved handle for a manually operated implement which assists in relieving the user of the common back strain caused by manual implements with prior art handles. 
   These and other objects are accomplished by the present invention, a uniquely configured curved handle for manually operated implements. The handle has a straight segment extending to a first curved segment having a uniform radius of curvature and a second curved segment having a different uniform radius of curvature, extending from the first segment. The handle has two working ends and a threaded connection on each end for securing various cleaning or other working members or attachments. This multi-use handle can thus be used in implements performing numerous different applications on horizontal, vertical and elevated surfaces. 
   The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention, itself, however, both as to its design, construction and use, together with additional features and advantages thereof, are best understood upon review of the following detailed description with reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is an elevation view of the curved handle of the present invention. 
       FIG. 2  is an exploded elevation view of a manually operated implement, a pushbroom, employing the curved handle of the present invention with a pushbroom head. 
       FIG. 3  is an elevation view of an assembled manually operated implement, a pushbroom, employing the curved handle of the present invention with a pushbroom head. 
       FIG. 4  is an elevation view of a prior art handle secured to a cleaning attachment, a pushbroom head. 
       FIG. 5  is a cross-section view taken from  FIG. 1 . 
       FIG. 6  is a cross-sectional elevation view showing the manner of locking connection between the handle of the present invention and a working attachment such as a pushbroom head. 
       FIG. 7  is an elevation view, in partial section, showing the sleeve and cover at the end of the handle of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   Handle  1  of the present invention comprises an integral, solid, unbendable elongated shaft  2  having first working end  4  and second working end  6 . Threaded connector  8 , with threaded end  10  and multi-sided sleeve  12 , is located at end  4  and threaded connector  14 , with threaded end  16  and cylindrical sleeve  18 , is located at end  6 . 
   Handle  1  can be of a given length of any dimension convenient for use with a manual implement, such as a pushbroom or mop or other working tool, but it has been found that a length, excluding the length of connectors  8  and  14 , in the range of fifty to sixty inches to be the most ergonomic. 
   Significantly, handle  1  has substantially straight segment  1   a , extending from connector  8  at end  4 . Straight segment  1  a has length L which represents @ 15-20% of the overall length of handle  1 . The remaining length of handle  1 , from the terminus of straight segment  1   a  to connector  14 , is a smoothly curved, continuously concave section. This curved section comprises first curved segment  1   b  and second curved segment  1   c . Curved segment  1   b  extends from the terminus of straight segment  1   a  in a uniform radius of curvature R 1  (measured from C 1 , the center of the circle of R 1 ) for a distance of 40-60% of the overall length of the handle. Segment  1   b  optimally has a uniform radius of curvature of approximately two times the length of the handle. Curved segment  1   c  extends in a smooth curve from the terminus of segment  1   b  for a distance of 30-35% of the overall length of the handle. Segment  1   c  optimally has a uniform radius of curvature R 2  (measured from C 2 , the center of the circle of R 2 ) of approximately one-third the length of the handle. The primary longitudinal axis of segment  1   c  approaches, but is not parallel to, the ground surface on which the working attachment to which the handle is to be connected is used. 
   For instance, an exemplar handle with an overall length of sixty inches, would have a straight segment  1   a  with a length of approximately ten and a half inches, a curved first segment  1   b  with a length of approximately thirty inches and a radius of curvature of 120 inches, and a curved second segment  1   c  with a length of approximately nineteen and a half inches and a radius of curvature of seventy-eight inches. A handle of these dimensions is disclosed merely for illustrative purposes. The handle of the present invention is not to be considered restricted to these or correspondingly proportional dimensions. 
   Handle  1  has the versatility to be used with attachments at either working end  4  or  6 .  FIG. 2  shows the components, pushbroom head  20  and locking nut  22 , which would be used when handle  1  is employed as a pushbroom at end  4 . It is contemplated that any type of attachment directed towards cleaning or other working application on a ground, floor or other horizontal surface, e.g. a floor squeegee, sponge or dust mop, roller mop, floor roller for applying adhesives and solvents etc., can be connected to end  4 . 
     FIG. 2  also depicts a cleaning or other type of working member or attachment, such as wall sponge  26 , configured to be secured at end  6 , to be used on vertical and elevated surfaces. Such attachments could include a wall squeegee, paint roller, sheetrock sander, scrub brush, and the like. 
   In the assembled pushbroom mode, shown in  FIG. 3 , pushbroom head  20  is secured to handle  1  via threaded end  10 , shown in  FIG. 6 , and locking bracket  38 . It is contemplated that locking bracket  38  would be similar to that which is described in U.S. Pat. No. 5,502,862. Locking nut  22  is provided to further secure the connection. 
     FIG. 5 , a cross-section of connector  8  taken from  FIG. 1 , shows flat surface  28  on threaded end  10 . Locking nut  22  comprises threads  30  which screw into corresponding threads  32  in pushbroom head  20 . Bottom surface  36  of locking nut  22  is also flat. When threaded end  10  of connector  8 , configured to be screwed into corresponding threads  33  of pushbroom head  20 , is fully threadably secured within the head, locking nut  22  is subsequently screwed into the head such that its flat bottom surface  36  contacts flat surface  28  of the threaded end. Tightening locking nut  22  against flat surface  28  provides an added, significant locking feature between handle  1  and head  20 , which may be used with or without pushbroom locking bracket  38 . As a practical matter, tightening locking nut  22  onto flat surface  28  provides a necessary locking means which ensures for a stable handle to head connection, not otherwise available. 
   As best seen in  FIG. 7 , removable connector cover  24  is cylindrical, corresponding to the cylindrical shape of sleeve  18  of connector  14 . Cover  24  has internal threads  25  which are configured to be threadably engaged with threaded end  16  of connector  14  to protect the threads and to provide for the comfort of the user. Compressible rubber or plastic O-ring  29  is positioned over the end of sleeve  18 , so that when cover  24  is tightened onto threaded end  16 , it squeezes O-ring  29  against the cylindrical sleeve, presenting a sealed and seamless fit. Base section of working attachment  26  configured to be secured to end  6  of handle  1 , has internal threading similar to cover  24 , so as to be threadably engaged against sleeve  18  and sealed via O-ring  29 . 
   Cover  24  comprises open hooked eyelet section  27 . Eyelet section  27  not only permits handle  1  to be hung for storage when a working attachment is secured to end  4 , but it also serves as a convenient hook component for reaching elevated areas where objects which otherwise may be out of reach can be retrieved. 
   The configuration of handle  1 , when employed on a pushbroom head or similar pushing implement, provides the user with an ergonomic tool which is quite effective in cleaning operations. As seen in  FIG. 3 , the pushing force applied at end  6  is more efficiently directed forward and downward, due to the connection of pushbroom head  20  to straight segment  1   a  and curved segments  1   b  and  1   c . In addition, and importantly, the curved configuration of handle  1  provides significant help in relieving back strain of the user, who is now free to assume a more comfortable and normal pushing position by remaining straighter and more upright, as shown in  FIG. 3 . 
   This is in contrast to the more awkward, fatiguing body position which is associated with straight handles.  FIG. 4  shows the common, representative straight handle  40  in use. The straight, more upwardly extending nature of the handle serves to decrease the effect of the pushing action, making it more difficult for the user, and requiring additional pushing force from a higher, less comfortable, less natural angle. As a result the user must assume more of a crouching position to do the work, thus resulting in increased strain to the back. 
   As shown in  FIG. 2 , located at end  6  of handle  1  is working attachment  26  which could be a wall sponge or brush, as discussed above, for cleaning vertical and elevated surfaces. Used in this mode, handle  1  is held around straight segment  1   a , which provides a ready handle portion, making it easier for the user to grasp and elevate handle  1  and working attachment  26 . Handle  1 , with its straight segment  1   a , thus provides a convenient and ergonomic straight handle portion, on handle  1  itself, to allow a user to easily hold and control the implement when it is to be elevated. 
   In addition, handle  1  of the present invention, when used on vertical and elevated surfaces, overcomes obstacles which straight handles do not address. The curvature of the handle creates increased leverage and thus allows for increased pressure on the work surface. The curvature also creates space between the user and the work surface. This is especially helpful when working overhead to keep debris from falling on the user, thus generally promoting a cleaner and safe work environment. 
   The disclosure herein, while it is directed to a handle with a shaft having a straight segment and two segments which comprise a smoothly curved, continuously concave section, is not to be considered as to be restrictive of the scope of the herein invention. For instance, depending on the desired angular curve on the handle, it is contemplated that the handle of the present invention may be configured with more than two curved segments with different radii of curvature, in order to make up the full length of the curved, concave section. The exact curvature or radius of curvature of each segment is also not to be considered limited to the herein disclosure. 
   Certain novel features and components of this invention are disclosed in detail in order to make the invention clear in at least one form thereof. However, it is to be clearly understood that the invention as disclosed is not necessarily limited to the exact form and details as disclosed, since it is apparent that various modifications and changes may be made without departing from the spirit of the invention.