Abstract:
The invention is directed toward a portable conversion table for a portable circular saw that facilitates conversion of commercial portable hand held circular saws into a table saw. It includes a work table with a working surface and a bottom surface clamping assembly which holds a portable circular saw, the table being provided with collapsible legs which permit the entire device to be broken down into a generally flat shape that can be easily transported.

Description:
RELATED APPLICATIONS 
       [0001]    There is no related application. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not applicable. 
       REFERENCE TO SEQUENCE LISTING, A TABLE OR A COMPUTER PROGRAM LISTING COMPACT DISC APPENDIX 
       [0003]    None. 
       BACKGROUND OF THE INVENTION 
       [0004]    1. Field of Invention 
         [0005]    The present invention is generally directed toward a conversation table for use in combination with a standard portable circular saw. In use, the combination approximates the functionality of a standard table saw but is sufficiently portable to be easily transported in a vehicle. 
         [0006]    2. Background of the Invention 
         [0007]    Portable power tools have long been available for use where their larger, shop-based versions would be impossible or otherwise impracticable to place into operation. Hence, for example, portable drills are used to perform many of the drilling tasks that are perhaps more easily completed using a drill press. Portable miter saws are available to perform some of the tasks a radial arm saw was previously used for, and portable circular saws are used in lieu of a standard table saw on jobsites or other locations where the conditions are not favorable for using the heavier duty tool. While these portable versions are handy, they generally suffer from a lack of precision. Conversely, while their larger, heavier-duty counterparts are much more precise, however their size and general heft make them unwieldy to transport and set up at a jobsite. What is needed therefore is a device that can essentially duplicate the function of the larger, bench-based devices while facilitating a degree of portability heretofore unavailable. 
         [0008]    The prior art discloses a number of portable circular power hand saw benches or tables which allow conversion of a portable circular power saw into a table saw. U.S. Pat. No. 4,133,360 issued Jan. 9, 1979 shows a bench with foldable legs and a work surface which has a portable circular saw blade aperture cut there through with parallel and elongated narrow secondary slots. A tool holding frame is adjustably mounted on the upper work surface of the bench. U.S. Pat. No. 6,546,978 issued Apr. 15, 2003 discloses a two part portable table saw stand having a large folding table with a lower shelf which holds a portable table saw so that the table of the saw is flush with the top of the folding table. U.S. Pat. No. 4,204,446 issued May 27, 1980 is directed toward a work table and hold down assembly for a power hand saw and U.S. Pat. No. 4,252,239 issued Feb. 24, 1981 is directed toward a carpenter combination portable power operated hand saw and table saw. U.S. Design Pat. No. 379,275 issued May 20, 1997 is directed towards a foldable workbench. 
       SUMMARY OF THE INVENTION 
       [0009]    The present invention is directed toward a portable conversion table for a portable circular saw which facilitates conversion of all commercial hand held circular saws into a table saw. The conversion table is simple and ruggedly built to withstand the abuses inherent in its use. Collapsible legs permit the entire device to be broken down into a generally flat shape that can be easily transported in a vehicle trunk or similar compartment. In use, the device is simply erected by deploying a secondary articulating leg, then fixing the table at the desired height and/or inclination. Thereafter, a portable circular saw is mounted to the underside of the work table such that its blade projects upwards through the working surface of the work table. The circular saw is subsequently plugged into the device&#39;s safety switch for use as a table saw. 
         [0010]    It is an object of the invention to produce a folding saw table that is easily transportable. 
         [0011]    It is another object of the invention to produce a saw table which can easily accommodate different makes and models of circular saws allowing the same to be utilized as table saws. 
         [0012]    It is still another object of the invention to produce a table which facilitates conversion of commercial hand held circular saw into a table saw in minutes. 
         [0013]    It is yet another object of the invention to provide a table saw which is easy to transport by one person. 
         [0014]    It is a further object of the invention to provide a table saw which stores compactly in a vehicle. 
         [0015]    It is yet another object of the invention to provide a table saw which has safety features including a momentary pressure switch and a safety switch. 
         [0016]    These and other objects, advantages, and novel features of the present invention will become apparent when considered with the teachings contained in the detailed disclosure along with the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0017]      FIG. 1  is a perspective view of the inventive table with legs extended and working surface tilted; 
           [0018]      FIG. 2  is a perspective view of the table shown in  FIG. 1  in a collapsed orientation, ready for stowage or transport; 
           [0019]      FIG. 3  is a side perspective view of the table shown in  FIGS. 1 and 2  fully erect and ready for the attachment of a portable circular saw; 
           [0020]      FIG. 4  is a front perspective view of the table shown in  FIGS. 1 ,  2 , and  3  fully erect, showing its blade guard, and accessories including a miter guide and fence; 
           [0021]      FIG. 5  is perspective view of the bottom surface of the work table; 
           [0022]      FIG. 6  is a perspective view of the table surface shown in  FIG. 5  with a portable circular saw mounted to the table; 
           [0023]      FIG. 7  is a side perspective view of a section of the table shown in  FIG. 6  and the portable circular saw; 
           [0024]      FIG. 8  is a partial front perspective view of the table and portable circular saw shown in  FIG. 6 ; 
           [0025]      FIG. 9  is a side perspective view of the table ready for use, showing the blade of the portable circular saw projecting through its working surface, the blade guard, accessory fence and miter guide; and, 
           [0026]      FIG. 10  is a perspective view of table in its collapsed orientation with the portable circular saw detached and the table stowed in a vehicle trunk. 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0027]    The present invention is directed towards a simple, ruggedly built, and robust conversion table allowing a portable circular saw to be mounted thereto and in combination function as a table saw. The preferred embodiments and best modes of the invention are shown in  FIGS. 1 through 10 . While the invention is described in connection with certain preferred embodiments, it is not intended that the present invention be so limited. On the contrary, it is intended to cover all alternatives, modifications, and equivalent arrangements as may be included within the spirit and scope of the invention as defined by the appended claims. 
         [0028]    The invention may be constructed from any suitable material but in a preferred embodiment, is manufactured from metal such as steel, aluminum, various metal alloys, and combinations therein. 
         [0029]    Turning now to  FIGS. 1 and 2 , the circular saw conversion table  15  is shown in partially erect ( FIG. 1 ) and collapsed ( FIG. 2 ) modes. Casters  20  are mounted to cross support members  120  which are in turn mounted to primary articulating legs  30  and secondary articulating legs  31  to facilitate moving the device, whether in its collapsed or its erect orientation. The generally planar, rectilinear work table  40  is designed to easily accommodate workpieces of any practicable size and in a preferred embodiment, measures approximately 26 inches along its long dimension and 18 inches along its shorter dimension and ranges from 27 inches to about 35 inches in height. In a preferred embodiment, it is cast from aluminum, and its working surface  41  is milled flat thereby ensuring the repeatable precision with regard to the cutting operations performed using this equipment. The work surface  41  additionally defines a plurality of apertures  42 , commonly referred to as dog holes, which are provided at regularly spaced intervals at opposing ends of the work table  40 . The holes  42  serve to both decrease the weight of the device  15 , thereby making it more portable, and more importantly, permit the insertion of bench dogs (not shown) to facilitate the handling of larger workpieces. An elongate rectangular blade aperture  43  is formed in the work table  40  allowing the table  15  is used in conjunction with a mounted portable circular saw  21  as shown in  FIGS. 6 through 9  to essentially duplicate the functionality of a standard table saw. The blade aperture  43  is sized to accommodate insertion of a portable circular saw blade but with sufficiently small tolerances relative to the kerf of the blade to minimize the likelihood that workpieces, parts thereof, or most catastrophically, the user&#39;s appendages will impinge operation of the blade. The blade aperture  43  is positioned substantially normal to the near end  46  and trailing end  47  of the work table  40  and substantially parallel to its sides  48 . A first accessory slot  44  and second accessory slot  45  are positioned parallel to the blade aperture and accommodate various accessories that may be provided with the table  15 . Additional accessory slots may be provided as desired, including additional slots parallel to and at varying distances from the circular saw blade, slots perpendicular to the circular saw blade, and slots at varying angles relative to the circular saw blade. The accessories are slidably mountable in the slots  44 ,  45  to thereby facilitate the precise and safe use of the table  15  and include, for example, a miter guide accessory  16  ( FIG. 4 ) whereby a workpiece may be guided into the saw blade at a precise angle. In a preferred embodiment, the first and second accessory slots  44 ,  45  are spaced at differing distances from the blade aperture  43  in order to provide maximum flexibility in the use of the accessories. For example, the accessory miter guide  16  may be utilized in both slots  44 ,  45  in order to create compound miters for the workpiece. A blade guard mounting point  35  is provided adjacent the trailing end  47  whereby a blade guard  18  is provided to safeguard the user from flying debris, kickback of the workpiece (for example, due to hitting a knot in a piece of wood). 
         [0030]      FIG. 3  shows a perspective side view of the inventive device including detail of the primary and secondary articulating legs  30 ,  31  comprising the support structure for the circular saw conversion table  15 . In a preferred embodiment, the articulating legs  30 ,  31  are manufactured from steel square bar stock, although any suitably rigid yet lightweight material may be used, including other metals, and molded, extruded, or blow-molded polymers. The primary articulating legs  30  are hingedly mounted at a proximal end via hinge  32  to work table  40 . Height adjustment sliders  37  are slidably mounted about the primary articulating legs  30  and are freely movable along the length of the legs  30 . Secondary articulating legs  31  are rotatably mounted at their proximal end to the height adjustment sliders  37  allowing the secondary articulating legs  31  to be rotated substantially parallel to the primary articulating legs  30  for stowage and transport of the table  15  as can be seen in  FIG. 10 . In operation, the table  15  is erected by rotating the secondary articulating legs  31  away from the first articulating legs  30  wherein said secondary articulating legs are prevented from further extension by a stop (not shown) built into the height adjustment sliders  37 . The height adjustment sliders  37  are then abutted against clevis pins  36  inserted into height adjustment holes  35  defined in the primary articulating legs  30  such that the mass of the work table  40  maintains the entire apparatus  15  in its erect position. The height adjustment holes  35  are placed such that the working height of the table ranges from about 27.5 inches to about 34.5 inches with the specific working heights preferably being 27½″, 29½″, 31¼″, 32¾″ and 34½″. However the height adjustment holes  35  may be placed at any position along the length of the primary articulating legs  30  according to the working height desired. Once erected to the desired working height, the work table  40  is then leveled (or tilted if so desired) using adjustment bolts  33  and locking thumbscrew  34 . 
         [0031]      FIG. 4  is a front perspective view of the inventive circular saw conversion table  15 . An accessory miter guide  16 , is shown placed in the first guide accessory slot  44 , and a fence  17  used for facilitating ripping and cross-cutting operations is mounted via a hand lock  17   a  to table end  46 . The blade guard  18  is shown positioned over the blade aperture  43 . A switchbox  50  is mounted beneath and adjacent the near end  46  of the work table  40  and includes an electrically connected power cable  51 , operational pressure switch  53 , a resettable fuse  52 , as well as a power plug receptacle  54 . Optionally, an interlock device  55  may be incorporated into said operational switch  53  to prevent unauthorized use of the conversion table  15 . In operation, the portable circular saw power plug (not shown) is simply plugged into the power plug receptacle  54  and the mounted portable circular saw is set for always-on operation by a trigger lock or other mechanism. Operation of the saw may then be controlled via the operational switch  53  thereby eliminating the danger that otherwise would be entailed by reaching beneath the table to trigger operation of the now-mounted portable circular saw. The resettable fuse  52  is provided to protect the portable circular saw motor from burning out in the event of an overload situation caused by a jammed workpiece. 
         [0032]      FIGS. 5 and 6  depict in perspective views the bottom surface of the work table  40 , showing the portable circular saw mounting surface  39  prior to mounting the portable circular saw ( FIG. 5 ) and with portable circular saw  21  mounted ( FIG. 6 ). A generally rectangular mounting plate  22  is mounted to the mounting surface  39  via mounting plate attachment bolts  23  as shown in  FIG. 6  affixed to the mounting surface  39  and mounting plate attachment nuts  24 . The portable circular saw  21  is then mounted to the device  15  via clamping means which affix the saw  21  to the mounting plate  22 . In a preferred embodiment, the mounting means include mounting clamp bolts  25  which are secured to the mounting plate  22  in a fixed position and clamp wing nuts  26  and an associated washer screwed on the bolts  25  with a plurality of universal mounting clamps  27 . The universal mounting clamps  27  are utilized to clamp the circular saw&#39;s shoeplate  28  to the mounting plate  22 . The universal mounting clamps  27  are generally elongate and may be manufactured from standard bar stock. An adjustment slot  29  is provided in each universal clamp member  27  facilitates mounting of an endless variety of commonly sold portable circular saws  21 . 
         [0033]    Mounting of a portable circular saw  21  is a simple operation, entailing removing the mounting plate  22  and affixing it to the portable circular saw shoeplate  28  with the universal mounting clamps  27 , making sure that the mounting plate  22  and portable circular saw  21  are aligned relative to one another. The now-combined portable circular saw  21  and mounting plate  22  are then bolted to the tables mounting surface  39  using the attachment bolts  23  and associated attachment nuts  24 . A secondary mounting clamp  38  directly mounted to the table is then utilized to further secure both the portable circular saw  21  and its mounting plate  22  to the mounting surface  39 . Finally, the portable circular saw  21  is set for always-on operation, and its power plug (not shown) is plugged into the power plug receptacle  54 . The device is now set upright, whereupon it is ready for use once it is plugged in. Since the saw was previously placed in its always-on mode, operation of the apparatus&#39; operational switch  53  energizes the portable circular saw  21 , causing its operation. This combination of the inventive portable circular saw conversion table  15  and now-mounted portable circular saw  21  is now operable to duplicate the function of a standard table saw, yet is extremely portable, being transportable in a vehicle trunk. Additionally, the mechanism by which the portable circular saw shoeplate  28  may be tilted in order to achieve certain cutting angles continues to be operable to cant the blade as desired even when mounted to the inventive table  15 . 
         [0034]      FIGS. 7 through 10  depict additional views of the table  15 , including detailed alternative views of its reverse, showing the mounting surface  39  with portable circular saw  21  attached.  FIG. 9  additionally shows the blade guard  18  in its operational position protecting the user from inadvertent contact with the saw blade  19 .  FIG. 10  depicts the inventive table  15  compactly stored for transport in a vehicle trunk. 
         [0035]    The principles, preferred embodiments and modes of operation of the present invention have been described in the foregoing specification. However, the invention should not be construed as limited to the particular embodiments which have been described above. Instead, the embodiments described here should be regarded as illustrative rather than restrictive. Variations and changes may be made by others without departing from the scope of the present invention as defined by the following claims: