Abstract:
A hand tool for servicing a power tool or other host tool is adapted to be readily mountable to and dismountable from the host tool via magnetic coupling. The hand tool includes a handle body, and a nut driver supported on the handle body. The handle body may define a bifurcated support, and the tool may include a pivot pin extending through the bifurcated support and the nut driver to support the nut driver on the tool. The nut driver defines at least one socket region dimensioned to receive a nut, and further is magnetized for magnetic coupling with a nut positioned within the socket region. In one embodiment, the nut driver houses a discrete magnet for this purpose. A second magnet may be supported on the handle body toward its central portion.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims the benefit of priority, under 35 U.S.C. 119(e), of U.S. Provisional Patent Application No. 61/898,896, filed Nov. 1, 2013, the entire disclosure of which is hereby incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates generally to hand tools and more particularly to accessories for manually-operated or power tools, such as gasoline- and electric-powered chainsaws. 
     BACKGROUND 
     The accessories of the present invention can be adapted for a variety of hand and power tools, including cutting tools such as motorized chainsaws. Generally, chain saws include a motor for powering the chain saw, a guide bar and a saw chain circulating about the guide bar. Chain saws are exemplary of many power tools for which the present invention is well-suited in that it is assembled using bolts/nuts made of metal that occasionally need to be tightened/loosed and/or include a housing or other components made of metal. 
     SUMMARY 
     The present invention provides a hand tool accessory for use in assembly, maintenance, and/or disassembly of the power tool. The hand tool is provided as a power tool accessory that is configured to be readily mountable to and dismountable from the power tool. Preferably, the hand tool accessory is readily mountable/dismountable via magnetic coupling with power tool. Thus, the hand tool accessory is storable on the power tool so that the hand tool tends to remain with the power tool at all times, including during use and operation of the power tool, so that the hand tool is readily available for use to assemble, maintain and/or disassemble the power tool, and tends not misplaced or lost at the point in time at which it is needed. 
     The hand tool includes a handle body, and a nut driver supported on the handle body. The handle body may define a bifurcated support, and the tool may include a pivot pin extending through the bifurcated support and the nut driver to support the nut driver on the tool. The nut driver defines at least one socket region dimensioned to receive a nut, and further is magnetized for magnetic coupling with a nut positioned within the socket region. In one embodiment, the nut driver houses a discrete magnet for this purpose. A second magnet may be supported on the handle body toward its central portion. The tool may be mounted to a host tool by position the host tool&#39;s nut within the socket region, thereby magnetically coupling the hand tool to the host tool. The handle body may be pivoted relative to the nut driver to fold against the tool body, with the second magnet magnetically coupling with the host tool&#39;s body to further support the hand tool on the host tool. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       An understanding of the following description will be facilitated by reference to the attached drawings, in which: 
         FIG. 1  is a front side view of an exemplary hand tool accessory in accordance with an exemplary embodiment of the present invention, shown in a folded position for storage; 
         FIG. 2  is a back view of the hand tool of  FIG. 1 , showing a screwdriver tip extended in an operative position; 
         FIG. 3  is a back side view of the hand tool of  FIG. 1 , showing the handle in an unfolded position in which the handle is axially aligned with the nut driver; 
         FIG. 4  is a top view of the hand tool of  FIG. 1 , showing the hand tool in the folded storage position; 
         FIG. 5  is a back view of the hand tool of  FIG. 1 , showing a screwdriver tip extended in an operative position; 
         FIG. 6  is a cross-sectional view of a nut driver of the hand tool of  FIG. 1 ; 
         FIGS. 7A-7D  are side, end, top, and perspective views, respectively, of the handle of the hand tool of  FIG. 1 . 
         FIGS. 8A-8D  show perspective, left side, top and right side views, respectively, of a screwdriver shaft of the hand tool of  FIG. 1 ; 
         FIGS. 9A-9D  show top, side, bottom and perspective views, respectively, of the knurled button of the exemplary hand tool of  FIG. 1 ; 
         FIGS. 10A-10C  shows top, side and perspective views, respectively, of the release plunger of the hand tool of  FIG. 1 ; 
         FIG. 11  shows the screwdriver shaft, knurled button and release plunger of  FIGS. 8A-10C  in an assembly including a spring mechanism; and 
         FIG. 12  is a perspective view of the pivot pin of the hand tool of  FIG. 1 . 
         FIG. 13  is a perspective view of an alternative embodiment of the hand tool, including an alternative embodiment of a nut driver that includes multiple socket regions of different sizes; 
         FIG. 14  is a side view of another alternative embodiment of the hand tool, including an alternative embodiment of the handle that includes multiple channels for housing multiple retractable screwdrivers; 
         FIG. 15  is a side view of yet another alternative embodiment of the hand tool, including an alternative embodiment of the handle that includes a an opening through the body for fastening a carabiner or other hook or clip, and a shaped edge providing a rib for driving a slotted fastener; and 
         FIG. 16  is a side view of still another alternative embodiment of the hand tool, including an alternative embodiment of the handle that includes not only the features of the embodiment of  FIG. 15 , but also defines a raceway for receiving a retractable blade carriage for providing retractable utility knife functionality. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1-12  show an exemplary hand tool accessory  10  in accordance with one aspect of the present invention. The exemplary hand tool accessory has a thin ergonomic body and a compact multi-tool design. 
     Referring now to  FIGS. 1 and 2 , the hand tool  10  may be used, for example, to loosen and tighten screws and nuts of a power tool, such as those of a chainsaw  2 . By way of example, a typical chainsaw includes chain bar nuts  4  and a tensioning screw  5  that tensions the cutting chain when replacing the chain from wear, or to take out the slack on the chainsaws cutting chain so it remains tightly within the guide bars chain slot during use, as best shown in  FIG. 2 . 
     The hand tool  10  includes a handle  12  that supports a nut driver  14 . In this example, the nut driver  14  has the form of a substantially conventional socket of a type often found in ratchet/socket sets. For chainsaws, for example, 10 mm, 13 mm, and 19 mm sockets will accommodate nearly all nuts of nearly all common, commercially-available chain bar nuts. 
     The nut driver  14  differs from a conventional socket in that it is modified in accordance with the present invention to be magnetic. In one embodiment, the nut driver body itself is magnetized. In a preferred embodiment, the nut driver  14  includes a fixedly attached magnet  18 , such as a neodymium magnet. In such an embodiment, the magnet  18  is preferably seated at the base of a nut-receiving socket region  15 , as best shown in  FIG. 6 . The exemplary nut driver  14  defines a pocket for receiving the magnet. The magnet  18  is positioned to couple magnetically with a nut, such as a chain bar nut  4 , when the nut is positioned in the nut driver&#39;s socket region  15 , to magnetically couple with the nut and support the hand tool  10  on the power tool  12 , as shown in  FIG. 3 . For example, a 0.125″×0.75″ neodymium magnet for a 19 mm, 12 point socket, and a 0.125″×0.50″ neodymium magnet for the 13 mm socket, have been found suitable for this purpose. 
     In a preferred embodiment, a second magnet  16  is adhered or otherwise fixedly attached to the handle  12  in a position disposed intermediate of a length of the handle  12 , to magnetically couple the hand tool  12  with the power tool&#39;s housing, to further assist in supporting the hand tool  10  on the power tool  2 , as will be appreciated from  FIGS. 1, 3 and 4 . This allows a user to magnetically couple the hand tool  10  to the power tool  2 , so that it will be secure and not fall off without the user applying some force to remove it. For example, a ⅛″×¾″ neodymium magnet has been found suitable for the second magnet  16 . 
     In a preferred embodiment, the nut driver  14  is pivotably-mounted to the handle  12 , to pivot on a pivot pin  40  (see  FIG. 12 ) extending through the nut driver  14  and a bifurcated support  17  of the tool&#39;s handle  10 , as best shown in  FIGS. 1 and 3 . The pivotable mounting of the nut driver  14  to the handle  10  allows the nut driver  14  to pivot and be magnetically drawn to the chain bar nut  4 , preventing it from slipping off during tightening or loosening of the nut, without applying enough force from the user to remove it. The pivoting nut driver  14  further allows the user to tighten or loosen the chain bar nuts at any angle within a 180-degree range of motion depending upon the leverage needed to tighten or loosen the chain bar nut, all while the nut driver  14  remains magnetically secured to the nut the user is working on. Further, it allows the handle  10  of the tool to be folded substantially flat against the body of the host power tool  2  for low-profile storage, as will be appreciated from  FIGS. 1, 3 and 4 . 
     The second body magnet  16  also provides a way to keep track of loose nuts by magnetically securing them to the tool, so that they will not be lost easily during disassembly. 
     In this exemplary embodiment, the tool  10  further comprises a retractable screwdriver  14  retractably housed within the body of handle  12 , as will be appreciated from  FIGS. 2, 3 and 5 . More specifically, the handle  10  defines internal channels for receiving and housing components of the retractable screwdriver mechanism, as shown in  FIGS. 7A-7D . 
     A slotted shaft  20  including a straight-head screwdriver tip  22  is shown in  FIGS. 8A-8D . The shaft  20  defines a longitudinally extending raceway  24 , a transversely-extending opening  26  for receiving a set screw  40  (see  FIGS. 10B and 11 ) for supporting a knurled button  50  (see  FIGS. 9A-9D ), and a spring-securing feature  28 , which in this embodiment is an opening  28 , at the end opposite the screwdriver tip  22 . 
     The slotted shaft  20  further defines a transversely-extending through-opening  30 . The through opening receives a pin  65  inserted during assembly through a release plunger  60 , as shown in  FIGS. 10B and 11 . The release plunger is spring biased outwardly by a spring housed within the body. An assembly including these components is shown in  FIG. 11 . 
     After assembly of the hand tool, the screwdriver tip  22  can be extended for use by sliding the knurled button  50  (and thus the slotted shaft  20 ) toward the proximal end of the tool handle  12 . This causes the pin  65  to ride in the raceway until it is in alignment with the through-opening  30 , at which point a compressed spring housed in the handle causes the pin to move transversely to the axis of the slotted shaft, engage the opening  30 , and lock the slotted shaft  20  in the extended position, as shown in  FIG. 5 . At this point, a retraction spring  70  (see  FIG. 11 ) attached to the spring securing feature  28  and an internal portion of the housing  12  is stretched and storing energy. Further, the release plunger&#39;s tip  62  is positioned in alignment with or proud of the tool handle  12 , as shown in  FIGS. 2 and 5 . 
     After using the screwdriver (e.g., to adjust a tensioning screw of a chainsaw housed between the chain bar nuts, as shown in  FIG. 5 ), the screwdriver tip  22 /slotted shaft  20  may be retracted into the body of the handle  12 . This is achieved by depressing the tip  62  of the release plunger  60 , as will be appreciated from  FIG. 5 . Such depressing causes the pin  65  to exit the through-hole  30 , at which point the retraction spring  70  resiles to retract the slotted shaft while the pin  65  rides in the raceway  24  of the slotted shaft. The spring  70  may be secured to the body by way of a loop/pin and stud inserted through a transversely extending hole/port in the handle  12 . 
       FIG. 13  is a perspective view of an alternative embodiment of the hand tool  10 . This embodiment is similar in many respects to that described above with reference to  FIGS. 1-12 . However, in this embodiment, the nut driver  14  that includes multiple socket regions of different sizes. For example, the hand tool accessory  10  may be provided with a larger (e.g., 19 mm) socket/nut driver, having a bored out portion on its base for receiving a smaller (e.g., 10 mm or 13 mm) housed and/or press fit into the base. It may be configured with similar openings on its base to receive the pivot pin  40 , such that the same pivot pin  40  passes through both sockets/nut drivers in the same fashion. By pivoting the dual-driver body the larger sized socket side may be exposed to accept a larger chain bar nut/fastener to tighten or loosen with magnetic draw and the smaller sized socket side may be exposed to accept a smaller chain bar nut/fastener. 
       FIG. 14  is a side view of another alternative embodiment of the hand tool accessory  10 . This embodiment is similar in many respects to that described above with reference to  FIGS. 1-12 . However, in this embodiment, the handle  12  is configured to include multiple internal channels  11   a ,  11 , b ,  11   c , for housing multiple retractable screwdrivers, each of which is configured similarly to that shown in  FIGS. 8A-8D , but which collectively include different screwdriver tips, such as slotted or straight-tip  22   a , a Phillips or other cruciform tip  22   b  and a Torx or other star tip  22   c . It will be appreciated that the handle  12  is shown in  FIG. 14  with a cutaway portion to reveal the internal channels  11   a ,  11   b ,  11   c  for illustrative clarity. 
       FIG. 15  is a side view of yet another alternative embodiment of the hand tool accessory. This embodiment is similar in many respects to that described above with reference to  FIGS. 1-12 . However, in this embodiment, the handle  12  is configured to define an opening  17  extending through the handle body  12 . The opening  17  provides a mounting point for fastening a carabiner or other hook or clip, rope, chain or other fastener. Further, this exemplary embodiment of the handle includes an edge portion that is shaped to provide a rib that is narrow, relative to the thickness of the body, and that is dimensioned to serve as a blade or driver for driving a slotted fastener, e.g., to open or close a slotted gas cap of a power tool. Further, in this exemplary embodiment, the handle includes a highly-reflective surface portion, such as reflective tape applied to the handle  12 , to enhance visibility of the tool in brush, tall glass, leaves, etc., and thus to facilitate retrieval of a lost tool, particularly with a flashlight in low-ambient-light conditions. 
       FIG. 16  is a side view of still another alternative embodiment of the hand tool accessory. This embodiment is similar in many respects to that described above with reference to  FIGS. 1-12 . However, in this embodiment, the handle  12  is configured to define a raceway  19 , the handle being shown in  FIG. 16  with a cutaway portion to show the raceway with illustrative clarity. The raceway structure, blade carriage/button  21  and blade  23  may all be of a conventional type of the type used in conventional utility knives. Accordingly, this embodiment of the hand tool accessory further provides retractable utility knife functionality. 
     Having thus described a few particular embodiments of the invention, various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements as are made obvious by this disclosure are intended to be part of this description though not expressly stated herein, and are intended to be within the spirit and scope of the invention. Accordingly, the foregoing description is by way of example only, and not limiting. The invention is limited only as defined in the following claims and equivalents thereto.