Abstract:
A portable assembly is provided in which a power tool can be mounted on a rotatable plate. The plate is large enough to allow the saw to travel above a worksurface. When the plate is in a reference orientation, a workpiece on the support surface below the plate can be cross-cut or rip-cut. When the plate is offset from the reference orientation, the workpiece can be miter-cut, compound-miter cut, or rip-cut. When working with large workpieces, the plate with the power tool can be inverted, transforming the assembly into a table saw. The plate is preferably configured to allow popular sized power saws, jig saws, and routers to be mounted and used in the above manner. Multiple standard width guide plates can be provided with the assembly, to minimize the need to adjust the guide rails.

Description:
[0001]    This application is a continuation-in-part of U.S. patent application Ser. No. 12/275,197, filed 20 Nov. 2008, which is incorporated by reference herein, and claims the benefit of U.S. provisional patent applications 61/081,385 filed 16 Jul. 2008, 61/097,855, filed 17 Sep. 2008, 61/376,259, filed 23 Aug. 2010, and 61/384,277, filed 19 Sep. 2010. 
     
    
     BACKGROUND AND SUMMARY OF THE INVENTION 
       [0002]    This invention relates to the field of power tools, and in particular to a portable assembly that allows a power hand saw, or other cutting tool, to be used as a cross-cut or miter saw, as well as a table saw. 
         [0003]    The cost of power tools continues to increase, as does the space and weight that is consumed by the variety of specialized tools normally used in construction projects. 
         [0004]    It would be advantageous to allow one power tool to perform multiple purposes, and in particular, it would be advantageous to allow a power hand saw, or other cutting tool, to be used as a cross-cut saw, a miter saw, and a table saw. 
         [0005]    These advantages, and others, can be realized by a portable assembly in which a power saw can be mounted on a rotatable plate. The plate is large enough to allow the saw to travel above a worksurface. When the plate is in a reference orientation, a workpiece on the worksurface can be cross-cut or rip-cut. When the plate is offset from the reference orientation, the workpiece can be miter-cut or rip-cut. When working with large workpieces, the plate with the power saw can be inverted, transforming the assembly into a table saw. The plate is preferably configured to allow popular sized power saws, jig saws, and routers to be mounted and used in the above manner; or, multiple plates can be provided with the assembly. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    The invention is explained in further detail, and by way of example, with reference to the accompanying drawings wherein: 
           [0007]      FIGS. 1A-1C  illustrate an example cross-cut, rip-cut, miter, table saw assembly. 
           [0008]      FIGS. 2A-2B  illustrate an example invertable and rotatable plate. 
           [0009]      FIGS. 3A-3F  illustrate an example plate with power tools. 
           [0010]      FIGS. 4A-4B  illustrate example attachment elements for attaching a power tool to the rotatable plate. 
           [0011]      FIGS. 5A-5B  illustrate an example adjustment of guides to accommodate a power tool. 
           [0012]      FIG. 6  illustrate an example guide plate. 
           [0013]      FIGS. 7A-7C  illustrate an example support plate and fences. 
           [0014]      FIG. 8  illustrates an example extendable assembly. 
       
    
    
       [0015]    Throughout the drawings, the same reference numerals indicate similar or corresponding features or functions. The drawings are included for illustrative purposes and are not intended to limit the scope of the invention. 
       DETAILED DESCRIPTION 
       [0016]    In the following description, for purposes of explanation rather than limitation, specific details are set forth such as the particular architecture, interfaces, techniques, etc., in order to provide a thorough understanding of the concepts of the invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments, which depart from these specific details. In like manner, the text of this description is directed to the example embodiments as illustrated in the Figures, and is not intended to limit the claimed invention beyond the limits expressly included in the claims. For purposes of simplicity and clarity, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail. 
         [0017]      FIG. 1A  illustrates a perspective view of an example cross-cut, rip-cut, miter-cut, and table saw assembly  100  in accordance with aspects of this invention.  FIG. 1B  illustrates a rear view, and  FIG. 1C  illustrates a side view. Because the assembly  100  is symmetric, the user may choose which side is the ‘front’; that is, which side the user will typically face when operating the tool. Note that particular features of the assembly  100 , detailed below, are not illustrated, so as not to detract from an understanding of the basic principles of this invention. The parent application of this continuation-in-part includes details regarding similar features, and is published as USPA 2010/0011929, dated 21 Jan. 2010. 
         [0018]    A base  110  includes a base top  115  with a circular opening  116  that is arranged to accept a circular plate  150  that is configured to guide and/or support a power tool, such as a power saw, jig saw, router, and so on. The plate  150  includes a slot  158 , and a pair of guides  155  on either side of this slot  158 . In this example, the guides  155  are configured to allow a base plate of the power tool to fit below a portion  156  of the guides  155 , as detailed further below. One of skill in the art will recognize, however, that the guides  155  could be shaped without this overlapping portion  156 . One of skill in the art will also recognize that a single guide  155 , with or without portion  156 , may be used, wherein the user guides the power tool against the guide  155  as it is pushed across the plate  150 . The example guides  155  include slots  157  for receiving a fastening element that allows for adjusting the guides  155  to accommodate particular tools, as detailed further below. 
         [0019]    In accordance with an aspect of this invention, the plate  150  includes features that allow the power tool to be fixedly attached to the plate  150 , detailed further below. When the power tool is affixed to the plate  150 , the plate  150  with the attached power tool can be placed in the circular opening  116  in an inverted position, with the operational element (saw blade, router bit, etc.) facing up. This inverting capability allows the assembly  100  to be used as a table-saw, a routing table, and so on. Advantageously, in this inverted configuration, large workpieces can be accommodated. For ease of understanding, the term ‘table-saw’ is used to identify the configuration wherein the operational element is facing up, regardless of the particular type of power tool being supported by the plate  150 . In like manner, the term ‘blade’ is used to identify the operational element, regardless of the particular type of operational element (saw blade, router bit, etc.). 
         [0020]      FIG. 1B  illustrates example electrical connections for providing power to the tool. In this example, an outlet box  180  is configured to include a male plug  181  for receiving an extension cord that is plugged into a source of power, and a female outlet  182  for receiving the plug of the power cord of the tool. The plug  181  and outlet  182  are preferably coupled via a power switch  185 . To facilitate emergency shut-off, the power switch  185  is preferably a push-pull switch, wherein when it is pushed in power is shut off, when it is pulled out, power is provided to the outlet  182 . Other configurations for providing power will be evident to one of skill in the art. 
         [0021]      FIG. 2A  illustrates a top view of the assembly  100  when a power tool  210  is atop the support  150 , in the non-inverted configuration, herein termed the ‘blade-down’ position.  FIG. 2B  illustrates a top view of the assembly  100  when the power tool  210  is attached to the support  150  and the support  150  is in the inverted, table-saw configuration. 
         [0022]    Returning to  FIGS. 1A-1C , the example assembly  100  includes a removable workpiece support  120 , and workpiece openings  112  that allow the workpiece to be placed beneath the plate  150  when the plate  150  is used in the blade-down position. The support  120  is supported by rails  125 . The example workpiece support  120  is illustrated with a circular kerf opening  126  that allows the blade of the power tool to extend below the workpiece. In a preferred embodiment, a variety of kerf plates may also be provided for placement in the opening  126 , to optimize support for the workpiece for particular tasks. For example, if the assembly is being used to perform cross-cuts while in a reference orientation (e.g. normal to the front of the assembly  100 ), a kerf plate with a single kerf slot that extends from front to rear may be used. In accordance with an aspect of this invention, the assembly  100  also includes openings  114  that allows the workpiece to travel from front to rear of the assembly for performing rip cuts while the plate  150  is in this same reference position, using this same kerf plate. 
         [0023]    The workpiece support  120  is also preferably configured to support a fence, not illustrated, for orienting or guiding the workpiece beneath the plate  150 . Preferably, two types of fences are provided. For cross-cuts and miter-cuts, wherein the workpiece is introduced via the side openings  112 , a pair of removable fence portions are attached to either the support  120  or the aforementioned kerf plate on either side of the kerf slot or opening, parallel to the front of the assembly  100 . For rip-cuts wherein the workpiece is introduced via the front or back openings  114 , a movable fence that extends from front to rear of the assembly  100  is used. Such a fence may be structured to clamp to the front and rear surfaces of the base  110 , at the lower edge of the openings  114 , as detailed below. 
         [0024]    The opening  126  in the support  120  also provides clearance for the power tool when the assembly  100  is used in the table-saw configuration, in most cases. If the power tool does not fit within the opening  126 , the support  120  can be removed. 
         [0025]    In a preferred embodiment, the assembly  100  also includes a removable drawer  130 . This draw  130  advantageously collects the saw dust or other waste material produced while working on the workpiece. This drawer  130  may also include covered partitions for storing small tools, preferably outside the region where most of the waste will fall. The drawer  130  may also include a hose attachment at the rear, for coupling to a shop-vac or other waste collecting device. 
         [0026]    In operation, the assembly  100  will generally be used in the blade-down configuration for cutting lumber and boards, and in the table-saw configuration for cutting sheet material. Rip cutting can be performed in either configuration, depending upon the width of the workpiece and the width of the rip. It is envisioned that this invention will be embodied in at least two sizes, an all-purpose size, and a smaller utility size. To accommodate a variety of tool in the table-saw configuration, the base unit  110  in each size will be about 8″ tall. 
         [0027]    In the all-purpose size, because common board sizes extend up to 2″× 12 ″ (1½″×11½″ finished), the size of the openings  112  and  114  is preferably at least 2″×12″; for ripping, the board may be offset, so the front and rear openings  114  are preferably wider than 12″. That is, assuming that the saw blade is in the center, an opening  114  of 23″ will allow the 12″ (11½″) board to be ripped on either side of the blade. In like manner, power saw blades are typically 8″ in diameter; accordingly, the length of the slot  158  is preferably at least 24″ (8″ start location of saw, 12″ travel, 4″ end location of saw). Thus, the base unit of the all-purpose size will be in the order of 30″×30″. 
         [0028]    The smaller utility size is designed for the most common applications, using, for example, 2″×8″ as the largest board size that should be accommodated. In this case, the openings  112  are preferably 2″×8″, and the openings  114  are preferably 2″×16″. The slot  158  may be 20″ long (8″ start+8″ travel+4″ end), although a shorter length may be sufficient due to the fact that the full width/diameter of the blade does not extend below the saw, and the nominal  8 ″ board is 7½″ wide). In a preferred embodiment of the utility size embodiment, the slot  158  is about 3″ wide and 18″ long. Thus, the base unit of the all-purpose size will be in the order of 24″×24″. 
         [0029]      FIGS. 3A-3F  illustrate a variety of example configurations of different power tools with respect to the support  150 . 
         [0030]      FIGS. 3A-3B  illustrate a power saw  310  in the non-inverted, blade-down configuration, and in the inverted, table-saw configuration.  FIGS. 3C-3D  illustrate a router  320  in the non-inverted, blade-down configuration, and in the inverted, table-saw configuration.  FIGS. 3E-3F  illustrate a jig-saw  330  in the non-inverted, blade-down configuration, and in the inverted, table-saw configuration. In the table-saw configuration, a fastening device  350  affixes the tool  310 ,  320 ,  330  to the support plate  150 . 
         [0031]      FIG. 4A  illustrates an example attachment of a router  320  to the plate  150 . In this embodiment, the router is attached via mounting holes  435  in the plate  430  of the router  320 . A thumbscrew  410  extends into receptors  415  in the plate  150 . In a preferred embodiment, the receptors  415  are situated in tracks that allow them to be spaced appropriately to align with the holes  435  in the plate  430 . 
         [0032]      FIG. 4B  illustrates another example attachment of the router  320  to the plate  150  via fastening devices  350 . As in the example of  FIG. 4A , a thumbscrew  410  extends into receptors  415  in the plate  150 . Referring to  FIG. 1 , these receptors  415  may be placed below the center slots  157  in the guides  155 , allowing the tool to be fastened to the plate  150  without removing the guides  155 . As illustrated in  FIG. 4B , the fastening device  350  includes a U-shaped element  420  that is configured to apply pressure to the base  430  of the router  320  when the thumbscrew  410  is tightened. One of skill in the art will recognize that other tool attachment techniques, common in the art, may alternatively be used. 
         [0033]      FIGS. 5A-5B  illustrates the use of the guides  155  when a power saw  310  is used in the blade-down configuration of the assembly  100 . In these examples, thumbscrews  510  extend into receptors  515  in the plate  150 , through the slots  157  ( FIG. 1 ) in the guides  155 . As noted above, the slots  157  allow the guides to be adjusted to accommodate the particular size of the plate  530  of the power saw  310 . When the guides are in the appropriate locations, the thumbscrews  510  are tightened to hold the guides in their proper place, The overlapping portions  156  of the guides  155  are shaped to overlay the plate  530 , yet allow the saw  310  to be pushed along the guides  155  by the user. As also noted above, these overlapping portions  156  are optional, as is the use of two guides  155 . 
         [0034]    As illustrated in  FIG. 5B , the opening  158  in the support plate  150  is sized sufficiently to allow the power saw  310  to be tilted, thereby allowing for angled cuts as well as compound-miter cuts. 
         [0035]    In a preferred embodiment of this invention, spacers may be provided to elevate the guides  155  above the surface of the plate  150 , allowing for different thicknesses of plates  530 . 
         [0036]    As will be evident to one of skill in the art, some tools may not have a plate that is suitable for use with the guides  155 , or suitable for use with the fastening device  350  ( FIG. 3 ). In a preferred embodiment of this invention, a guide plate may be provided to facilitate the use of a variety of tools. 
         [0037]      FIG. 6  illustrates an example guide plate  610 . The guide plate  610  is illustrated as having tongues  655  that fit within the guides  155 , and a thicker region  650  that supports the tool and allows it to extend above the guides  155 , as required. Preferably, the plate will be made of a workable material, such as plastic, so that the user can form the appropriate cutouts and attachment holes. A plurality of guide plates  610  may be provided with the assembly  100  so that the user can attach the plates  610  to a variety of tools. In this manner, if each guide plate is the same width, adjustments to the guide rails for different tools will not be required. 
         [0038]      FIG. 7A  illustrates an example support plate  150  with cutouts  758  that facilitate viewing of the workpiece (not illustrated) while it is placed in position along a set of removable fences  710 . The fences  710  are removable in order to allow the workpiece to be introduced from the front or rear for rip-cuts, without rotating the saw. The guides  155  are not illustrated in this figure, so as not to obscure the figure, but they would be positioned on the surface on either side of the slot  158 . 
         [0039]    Also illustrated in  FIG. 7A  are detents  720  that facilitate positioning of the support plate  150  on the top surface  115  of the assembly  100 . In this example embodiment, the top  115  includes a ledge  715  that supports the rotatable plate  150 .  FIG. 7B  illustrates a cross section view of the top  115  with the plate  150  situated on the ledge  715 . To facilitate adjustment of the rotatable plate  150 , the ledge  715  includes bearings  725  at the locations of the detents  720 . As the plate  150  is rotated, it will either be rotatably supported by these bearings  725 , or fixedly supported as the bearings  725  engage the detects  720 . The detents  720  are situated on both sides of the plate  150 , so that they can engage the bearings in both the non-inverted blade-down configuration and the inverted table-saw configuration. 
         [0040]    The detents  720  are illustrated as being spaced at 45° around the support plate  150 , although other spacings may be used as well. In this manner, the plate  150  can be easily placed at the reference orientation for crosscuts and ripcuts and a 45° orientation for mitered corner cuts. At other angles, one or more receptors  730  are situated on the top  115 , near the perimeter of the plate  150 . As in  FIG. 4 , a fastening device  350 , comprising a thumbscrew  410  and U-shaped element  420  can be used to apply pressure to the plate  150  to hold it at the desired angle. Not illustrated in  FIG. 7A , the plate  150  or the top  115  is preferably labeled or engraved with graduation marks around at least a section of the perimeter of the plate, indicating the relative angle of the plate  150  with respect to the top  115 , and, correspondingly, relative to the fence  710 . Also in a preferred embodiment of this invention, linear graduation marks are places along the edges of the top  115 , to facilitate measuring and marking the workpiece without a separate measuring device. 
         [0041]      FIG. 7C  illustrates a fence  770  that can be used on the top  115  when the assembly  100  is in the blade-up table-saw configuration, or on the support  120  when ripping in the blade-down configuration. The fence  770  includes a rear flange  772  that includes a lip for wrapping around the edge of the top  115 , or the rear support rail  125  for the support  120  ( FIG. 1 ). The fence  770  also includes a front flange  774  with a thumbscrew that can apply pressure to the front edge of the top  115 , or the edge of the front support rail  125 . 
         [0042]    To support large workpieces, such as plywood sheets,  FIG. 8  illustrates an assembly with extendable supports  810 . In this example embodiment, a pair of telescopic rods  820  allows the support  810  to be extended to an appropriate width so that the upper surface  815  of the support  810  is able to support the workpiece. Also illustrated in  FIG. 8 , the support  810  includes notches  812  that facilitate the use of the example fence  770  in  FIG. 7 . As compared to the example of  FIG. 1 , the example of  FIG. 8  illustrates a thinner support wall  830 , allowing for wider workpieces at the lower worksurface  120 . 
         [0043]    The foregoing merely illustrates the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention and are thus within its spirit and scope. For example, the example embodiments include a circular support plate that facilitates miter cuts, although one of skill in the art will recognize that a simpler embodiment may provide for cross-cuts, rip-cuts, and table-saw features, without the miter feature, obviating the need for a circular support plate. Because such an embodiment would not necessarily require symmetry, the aspect ratio of the assembly could be optimized for a particular set of tasks. For example, a long and narrow assembly could provide the length needed for cross cutting wide boards when the blade is parallel to the long dimension, and with the blade perpendicular to the long dimension, could provide the width needed to support wide sheet material in the table-saw configuration. Also, an alternative for the cutouts in the support plate is the use of a relatively transparent material to form the support plate, such as glass, plexiglas, or other polycarbonates. The top of the base may also comprise transparent material. These and other system configuration and optimization features will be evident to one of ordinary skill in the art in view of this disclosure, and are included within the scope of the following claims. 
         [0044]    In interpreting these claims, it should be understood that: 
         [0045]    a) the word “comprising” does not exclude the presence of other elements or acts than those listed in a given claim; 
         [0046]    b) the word “a” or “an” preceding an element does not exclude the presence of a plurality of such elements; 
         [0047]    c) any reference signs in the claims do not limit their scope; 
         [0048]    d) several “means” may be represented by the same item or hardware or software implemented structure or function; 
         [0049]    e) each of the disclosed elements may be comprised of hardware portions (e.g., including discrete and integrated electronic circuitry), software portions (e.g., computer programming), and any combination thereof; 
         [0050]    f) hardware portions may include a processor, and software portions may be stored on a non-transient computer-readable medium, and may be configured to cause the processor to perform some or all of the functions of one or more of the disclosed elements; 
         [0051]    g) hardware portions may be comprised of one or both of analog and digital portions; 
         [0052]    h) any of the disclosed devices or portions thereof may be combined together or separated into further portions unless specifically stated otherwise; 
         [0053]    i) no specific sequence of acts is intended to be required unless specifically indicated; and 
         [0054]    j) the term “plurality” of an element includes two or more of the claimed element, and does not imply any particular range of number of elements; that is, a plurality of elements can be as few as two elements, and can include an immeasurable number of elements.