Patent Abstract:
A concrete finishing tool includes a body having a chassis, a guard, and frame supports. An extension handle is attached to the body, and a motor is attached to the body and operatively connected to a driving gear and driven gear to rotate blades having a quick change coupling mechanism. An integrated handle is configured on the body and houses a switch for the motor that is powered by a power supply.

Full Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority to U.S. Provisional Patent application No. 61/383,656, filed Sep. 16, 2010, the entire content of which is incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention generally relates to manually operated finishing tools, and, more particularly, to concrete finishing tools having a trowel or a surface finishing attachment in combination with a cordless power tool and a light. 
     Freshly poured concrete begins to cure immediately, and may be formed, smoothed, and finished to achieve its final form using hand-held, manually operated tools that may include a trowel and a brush that may be attached to a long boom handle for finishing larger surface areas. Some finishing tools are not suitable for use on smaller surface areas and surfaces having hard to reach areas. Some finishing tools require significant manual effort to achieve a smooth or finished surface and thus result in considerable fatigue when working with larger surface areas and heavier concrete. Some finishing tools are bulky and are cumbersome when maneuvering around difficult to reach places. Some finishing tools only allow linear patterns or finishes to be applied to a concrete surface. 
     As can be seen, there is a need for an improved apparatus for finishing freshly poured concrete surfaces that reduces fatigue on a user, provides an ability to maneuver into hard to reach areas, and provides an ability to apply non-linear, circular or wave-like finishes to the concrete surface. 
     SUMMARY OF THE INVENTION 
     In one aspect of the present invention, a cordless concrete finishing tool comprises a body having a chassis, a guard, and frame supports; an extension handle attached to the body; a motor assembled to the body and operatively connected to a driving gear; a driven gear interconnected to the driving gear, and disposed to rotate blades that are connected to the driven gear by a quick-change coupling mechanism; an integral handle configured on the body and disposed to house a switch for the motor; and a power supply disposed to provide power for the motor. 
     In another aspect of the present invention, a cordless concrete finishing tool comprises a body including an injection molded polymer formed as a chassis, wherein the chassis has an integrated handle&#39;and frame supports that support a guard; a threaded socket formed in, the body and disposed on an outside surface thereof; a rotating blade assembly housed by the guard; a motor operably connected to the rotating blade assembly by a driving gear and a driven gear; a variable speed switch operable to activate the motor; a light disposed on an outside of the body and operable to illuminate a working surface of the concrete finishing tool; and a removable power supply configured to power the motor. 
     These and other features, aspects and advantages of the present invention will become better understood with reference to the following drawings, description and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a side perspective view of a tool according to an embodiment of the present invention; 
         FIG. 2  shows a top plan view of the tool shown in  FIG. 1 ; and 
         FIG. 3  shows a bottom plan view of the tool shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The following detailed description is of the best currently contemplated modes of carrying out exemplary embodiments of the invention. The description is not to be taken in a limiting sense, but is made merely for the purpose of illustrating the general principles of the invention, since the scope of the invention is best defined by the appended claims. 
     Various inventive features are described below that can each be used independently of one another or in combination with other features. 
     Broadly, embodiments of the present invention generally provide a cordless concrete finishing tool that uses cordless motor technology to reduce the labor of the troweling process by reducing both a fatigue of a laborer and a time needed to trowel or finish a freshly poured surface. The finishing tool may be more practical for typical size jobs that may be more common than larger size jobs. The finishing tool may be portable and sized to make finishing hard to reach places possible and easy. 
     Referring to  FIGS. 1-3 , side perspective, top plan, and bottom plan views of an exemplary embodiment of the present invention are shown respectively. A cordless concrete finishing tool  10  may have a body  12 , a chassis  14 , and a guard  15  held or supported by frame supports  17 . A motor  16 , which may run on a battery  24 , may be provided for the tool  10 , along with an extension handle  18  that may have a threaded stud  20  that assembles to a socket  22  that may have a threaded hole  23 . The tool  10  may also include an integral handle  25 , which may house a variable speed switch  26 . One or more lights  28  may be provided for the tool  10 . A quick-change coupling  30  may be provided for blades  32 , along with a driving gear  34  and a driven gear  36  for rotating the blades  32 , which may include a plurality of blades on a carrier, to form a rotating blade assembly. 
     The body  12 , chassis  14 , and guard  15  may be made from an injection molded polymer or stamped metal, and may be capable of providing a rigid body construction. According to an exemplary embodiment, an overall size of the tool  10  may be about 5 inches wide, about 4 inches tall, and about 12 inches long. The tool  10  may include a handle  25  for gripping, and may include an extension handle  18 , which may be a pole or boom, for using the tool  10  in areas that may be out of arms reach. The handle  25  and extension handle  18  may be placed on the tool  10  at any suitable position, location, or angle. The blades  32  may comprise a set of four trowel blades, for example, and may be stainless steel or any other suitable rigid material. The tool  10  may include a cordless motor  16 , which may be a battery powered motor connected to one or more high voltage (e.g., 36 volt) batteries  24  (e.g., part of a removable power pack) that may have a battery transfer switch for when the battery  24  becomes drained, along with a low battery warning indicator. The tool  10  may be water proof, and may have one or more lights  28 , which may be disposed on the body  12  or the chassis  14 , and which may be activated by the variable speed switch  26 . The tool  10  may include a guard  15  for safety, which may contain and follow a contour of the rotating blade assembly, and may be configured in various shapes or sizes to prevent debris from being thrown by the rotating blade assembly and prevent from items from interfering therewith. A quick change coupling  30  may secure the blades  32  and may provide a tool-free replacement for possible optional attachments (e.g., float trowels or finish trowels). 
     The blades  32  may comprise a suitable blade configuration for troweling and may include a suitable connection means to attach the trowels to the motor  16 . The guard  15  may enclose the blades  32 , and may attach to the body  12  of the tool  10 . One or more gears may be provided on the inside of the body  12 , which may be configured to transfer power from the motor  16  to the driven gear  36 , which in turn may spin the trowels. An on/off switch may be provided which can allow power to get to the motor and drive the gears. The trowels may be configured to spin in either direction for smoothing the concrete. 
     To make an embodiment of the present invention, the body  12  may be molded or stamped and the motor  16  may be mounted thereto. The gears  34 ,  36  may be mounted to the body  12  and interconnected to the motor, which may be connected to all electrical connections and switch  26 . The trowels may be manufactured and welded. 
     In an alternative embodiment, the trowel heads may be changed from a float trowel to a finish trowel. The battery may be located in various locations, and the location of the lights may vary. The drive gears  34 ,  36  may vary in configuration to suit a particular purpose. The drive gears  34 ,  36  may be interconnected by a belt (e.g., toothed, V-belt, or flat belt) or chain. The body  12  may be configured in different styles having different types of guards  15  in various colors. 
     To use an embodiment of the tool  10 , a user may install a battery or batteries into the tool  10 , select the type of trowel needed for the job, and assemble the trowel on the quick change coupling  30 . The user may then place the tool on a slab of concrete and activate the switch  26 , which may allow the rotating motion of the trowels of the blades  32  to finish the concrete. 
     It should be understood, of course, that the foregoing relates to exemplary embodiments of the invention and that modifications may be made without departing from the spirit and scope of the invention as set forth in the following claims.

Technology Classification (CPC): 1