Abstract:
A device for obtaining miter saw settings for cutting material to mitered together wherein the settings may be obtained without measuring the angle of the surface material. The device comprises a frame having a setting scale and first and second pivotally attached arms, wherein the setting scale corresponds to the settings on a miter saw.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a device for providing miter saw settings, and more specifically, to device having a setting scale and a pair of pivot arms whereby the pivot arms are matched to angled surfaces to be fitted with material joined by mitering, and the arms are rotated against the setting scale of the device to provide the corresponding setting on a miter saw for making mitered cuts in the fitted material.  
         BACKGROUND OF THE INVENTION  
         [0002]    When shaping two pieces of material to be joined at a selected angle, there is always a significant problem in providing an angle on each piece such that the two angles will join to form the selected angle. Cutting pieces of wood with a miter guide on a table saw to form mating surfaces on separate pieces of wood to make a trim joint is but one example. In cutting trim for a house, for instance, most walls are not joined at perfect 90° angles. Thus, each individual corner must be measured separately and very accurately. Next, each separate angle measured must be converted into a measurement for a cut using a miter saw or a miter box. This is an extremely time-consuming and laborious process, particularly where each angle is different. Accordingly, few workers possess the requisite level of attention to detail to correctly perform this task. Also, the cutting scale on a miter saw is generally semi-circular, with markings from 0 to 45 on the left side of the semicircle, and from 0 to 45 or 60 on the right side of the semicircle. Thus, an angular measurement of greater than 45° does not correlate directly to the markings on a miter box.  
           [0003]    Traditionally, materials for mitered joints are cut using a largely trial and error process, with a significant rate of failure and the need to recut material frequently for all but very skilled finish carpenters. One reason for this failure is the difficulty of measuring wall angles ranging from acute (less than 90°) to obtuse (greater than 90°), very few of which are square (exactly 90°), with conventional measuring tools such as a compass or protractor. Other difficulties include calculating the proper angle at which to cut the material, since the appropriate setting on the miter saw is different from the measured wall angle for most angled surfaces, as discussed above. Moreover, if the saw cut is wrongly set for the first cut, the second piece will also be cut wrongly. Thus, it is important to be correct in making measurements and calculating correct saw settings based on such measurements.  
           [0004]    While devices for measuring wall angles for mitered cutting exist, these devices suffer from a number of drawbacks. First, measuring the wall angle and dividing by two will not provide the corresponding measurement on the miter saw for oblique angles. In a miter saw, 0 on the saw scale corresponds to an angular measurement of 90°. To cut miter cuts corresponding to acute or right angles, for instance, a 90° angle, the corresponding measurement on the miter saw is the angular measurement divided by 2. For obtuse angles, however, the calculation is different—the proper setting is calculated by taking 180 minus the angular measurement, divided by two. For example, if an outside angle measures 128°, the proper miter saw setting is (180-128)/2, or 26. Although carpenters know that 128 divided by 2 would not be a correct setting, many carpenters do not know the correct formula and thus the conventional practice is to guess at the correct miter saw setting. This practice of estimating understandably leads to frequent errors.  
           [0005]    A number of tools exist for measuring an angle between two planar surfaces, and such devices are generally two pivotally joined arms which are joined by a protractor scale indicating the angle between the two arms. Various configurations applying this general principle are known in the art. However, there are instances when the measure of the inner angle between two surfaces is inaccessible to such devices due to their shape. Also, these devices cannot conveniently measure outer angles (generally greater than 180°) because of the limited span of the setting scale used. Thus, traditionally, two separate instruments have been required to measure both inner and outer angles. Lastly, while these instruments provide surface angles, they do not provide or calculate miter saw settings.  
           [0006]    Therefore, there is a need for a single device that easily and rapidly provides miter saw settings for both inner and outer angular surfaces, that is easy to manufacture and has relatively few parts.  
         SUMMARY OF THE INVENTION  
         [0007]    Accordingly, it is an object of the invention to provide a device for obtaining miter saw settings for making angled cuts that correspond to angled surfaces, without the need to measure surface angles directly.  
           [0008]    A further object of the invention is to provide a single device that can be used to provide miter saw settings that correspond to both inner and outer surface angles.  
           [0009]    Yet another object is to provide a device for making rapid determinations of miter saw settings for material to be cut at an angle.  
           [0010]    Another object of the invention is to provide a device for obtaining miter saw settings for fitting material to angled surfaces whereby no calculations are needed.  
           [0011]    In accordance with the present invention, all of these objects, as well as others not herein specifically identified, are achieved generally by the present miter saw setting device which includes two pivotally joined segments attached to a scale having saw settings inscribed thereon.  
           [0012]    More specifically, the invention pertains to device for obtaining miter saw settings for cutting material to joined by mitering, wherein the material must correspond to an angled surface, such as a wall, and wherein the settings may be obtained without measuring the angle of the surface material. The device comprises two pivotally joined arms, a setting scale and lip, wherein the arms are placed in an orientation opposite the surface material, then rotated to rest against a measurement on the scale that provides the miter saw setting corresponding to the surface material. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a top perspective view of one embodiment of the invention.  
         [0014]    [0014]FIG. 2 is a perspective view of the device of the invention shown in position to provide settings for a miter cut to an inside angular surface.  
         [0015]    [0015]FIG. 3 is a perspective view of the device of the invention shown in position to provide settings for a miter cut corresponding to an inside angular surface.  
         [0016]    [0016]FIG. 4 illustrates placement of the pivotal segments along the setting scale to provide a cutting measurement. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0017]    Referring to FIG. 1, the device of the invention is generally designated as item  2 . The device  2  includes a first arm  4  and a second arm  10  and a frame  12 . The frame has a pointed end  6  and a blunt end  8 . Each arm  4  and  10  has an inner edge  14  and an outer edge  16 . The first and second arms,  4  and  10  respectively, are pivotally joined at a first pivot joint,  18 . The ends of the segments  4  and  10  are rounded near pivot joint  18  so that the edges  14  and  16  of the arms  4  and  10  can be placed against the surfaces being measured regardless of the angle formed between the surfaces. The first arm  4  is inscribed with a pointer  20 . A second pivot joint  22 , is formed between the second arm  10  and the frame  12 , near the blunt end  8 . The frame  12  is equipped with a setting scale  24 , which is inscribed with a series of markings,  26 . The markings are calibrated to indicate cutting measurements corresponding to the setting scale on a miter saw. The frame  12  is further attached to a lip  28 . The frame may be made of any suitable stiff material, such as but not limited to metal or plastic. In a preferred embodiment, the lip  28  is constructed of the same material as the frame  12 .  
         [0018]    As shown in FIG. 1, the structure near the pivotal joint  18  is described here in more detail. The two arms  4  and  10  are joined at the pivotal joint  18  by a screw  30  that engages an adjustable nut  32 , so that the angle between the arms  4  and  10  may be secured. Of course, many alternative ways to pivotally and adjustably fasten the arms  4  and  10  may be utilized without departing from the teachings of the present invention. The second pivot joint  22  need not be adjustable, and the second arm  10  and the scale  12  may be permanently pivotally attached with, for instance, a rivet  36 . Again, many alternative ways to pivotally fasten the second arm  10  and the scale  12  may be utilized without departing from the teachings of the present invention.  
         [0019]    The lip  28  is attached in a fashion perpendicular to the plane of the frame  12 , and forms a backstop on which to place the outer edge  16  of the second arm  10  during reading of the markings  26  on the setting scale  24 . The correct measurement on the setting scale  24  is indicated by the pointer  20 , when the outer edge  16  of the second arm  10  is positioned adjacent to and at least partly touching the lip  28 .  
         [0020]    Referring now to FIG. 2, the invention may be utilized to provide miter saw settings that match inside angled surface material, which is generally angled at 90° or less. The surface material may be any angled material for which matching angled material is needed. For example and not by way of limitation, the surface material may be a wall corner, and the matching material to be cut may be trim for that wall. The frame  12  is configured with a blunt end  8  to permit inner angle fittings, as illustrated in FIG. 2. To use the device of the invention to fit material to an inner angled surface such as, for instance, a wall  44 , the outer sides  16  of arms  4  and  10  are placed inside the wall angle  46  so that pivot joint  18  as adjacent to the inside angle point  48  of the inside surface  44  to be fitted. Once arms  4  and  10  are adjacent to the inside surface  44 , adjustable nut  32  is tightened such that the angular orientation of the arms is secured. Next, the arms are rotated about the second pivot joint  22  until the outer edge  16  of second arm  10  is resting on the lip  28 , and the pointer  20  is located on the setting scale  24 . To determine the appropriate measure on the miter saw, the marking  26  that corresponds to the position of the pointer  20  is read, as shown in detail in FIG. 4. This marking provides the miter saw setting that is appropriate for the measured angle.  
         [0021]    Referring now to FIG. 3, the invention may also be utilized to provide saw settings that match an oblique surface angle, such as an outer corner in a wall, as illustrated in FIG. 3. To use the device of the invention to obtain miter settings corresponding to an outside angular surface  34 , the inner sides  14  of arms  4  and  10  are placed around the angle  40  of the surface so that pivot joint  18  as adjacent to the point  42  of the angle in the outside surface  34  to be measured. Once arms  4  and  10  are adjacent to the angle  40 , adjustable nut  32  is tightened such that the angular orientation of the arms is secured. Next, the arms are rotated about the second pivot joint  22  until the outer edge  16  of second arm  10  is resting on the lip  28 , and the pointer  20  is located on the setting scale  24 . To determine the appropriate setting on the miter saw, the marking  26  that corresponds to the position of the pointer  20  is read, as shown in greater detail in FIG. 4. This marking corresponds to the measurement of the miter saw.  
         [0022]    Accordingly, the present invention provides a single new and convenient device that can be utilized to obtain miter saw settings for cutting materials to correspond to both inner and outer corners of any angled surface. Those skilled in the art will appreciate that no direct measurement of the wall angle or calculations are necessary to obtain the miter saw setting; this and the speed at which the settings are obtained are primary advantages of the invention.  
         [0023]    While particular embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes and modifications may be made thereto without departing from the invention in its broader aspects and as set forth in the following claims.