Abstract:
An apparatus and its method of use with a conventional tape measure confirms right angles of the corners of a rectangular structure. The apparatus is a two-part tool including a tape measure tab part and a tape measure tape part. The tab part secures a tape measure tab at one corner of the rectangular structure as the tape measure tape is pulled from the tape measure housing diagonally across the structure. The tape part of the apparatus is secured to the diagonally opposite corner of the structure and is used to check the diagonal distance measurement of the tape across the structure. The process is then again performed between the other diagonally opposite corners of the structure to obtain a diagonal distance measurement across the other corners to determine if the two diagonal measurements match and confirm the right angles of the rectangular structure.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention pertains to an apparatus and its method of use in confirming right angles of the corners of a rectangular structure by using the apparatus with a conventional tape measure. The type of tape measure referred to basically comprises a housing containing a coiled tape and a tab on an end of the tape that is pulled to pull the tape from the housing. More specifically, the present invention pertains to a two part tool including a tape measure tab part and a tape measure tape part, and their method of use. The tab part secures a tape measure tab at one corner of a rectangular structure as the tape measure tape is pulled from the tape measure housing diagonally across the structure. The tape part of the apparatus is secured to the diagonally opposite corner of the structure and is used to check the diagonal distance measurement of the tape across the structure. The process is then again performed between the other corners of the structure to obtain a diagonal distance measurement across the other corners to determine if the two diagonal measurements match and confirm the right angles of the rectangular structure. 
         [0003]    2. Description of the Related Art 
         [0004]    There is a well known method of using a tape measure to determine whether the corners of a rectangular structure, for example a rectangular frame or a rectangular panel are right angles. The method basically involves measuring the diagonal distance between a first pair of diagonally opposite corners of the structure and then measuring the diagonal distance between the second pair of diagonally opposite corners of the structure and determining if these two measurements are the same. If the measurements are the same, the right angles of the four corners of the structure are confirmed. 
         [0005]    This well known method of confirming that the corners of a rectangular structure are right angles is often performed with a tape measure. However, it is often difficult for a single person to perform the method. This is particularly true on larger rectangular structures where the person making the tape measure measurements cannot reach from one corner of the structure diagonally across to the opposite corner of the structure. In such situations, it is often necessary for the person using the tape measure to hook the tab at the end of the tape measure tape over one corner of the structure, and then extend the tape measure tape to the diagonally opposite corner of the structure to measure the diagonal distance between the corners. This method of measuring the diagonal distance between corners of a rectangular structure is disadvantaged in that often the tab at the end of the tape will slip off the engaged corner as the tape measure tape is extended to the diagonally opposite corner. 
       SUMMARY OF THE INVENTION 
       [0006]    The above described problem involved in confirming right angles of a rectangular structure by using a tape measure to measure the distance between diagonally opposite corners of the structure is overcome by the apparatus of the invention and its method of use. 
         [0007]    The apparatus of the invention is basically a two part tool that includes a tab part that is used with the tab at the end of the tape of a conventional tape measure, and a tape part that is used with the tape of the conventional tape measure. Basically, the tab part is secured to one corner of the rectangular structure and holds the tape measure tab while the tape is extended from the tape measure housing to the diagonally opposite corner of the rectangular structure. The tape part of the tool is secured to the diagonally opposite corner of the structure and provides an accurate determination of the distance measurement across the rectangular structure between the diagonally opposite corners. 
         [0008]    The tab part of the apparatus has a general triangular configuration with opposite top and bottom surfaces. A magnet is contained in the tab part between the top and bottom surfaces. 
         [0009]    First and second blocks project outwardly from the bottom surface of the tab part. The blocks are oriented at a right angle on the bottom surface. The blocks have respective first and second surfaces that oppose each other. The first and second side surfaces define a right angle between the surfaces. 
         [0010]    A cylindrical post projects outwardly from the tab part top surface. The post is rotatable on the tab part about a rotation axis. The rotation axis is positioned where it intersects the apex of the right angle formed by the first and second surfaces of the respective first and second blocks on the tab part bottom surface. A notch is formed in a top surface of the post. The notch is dimensioned to receive the tape measure tab inserted in the notch. 
         [0011]    The tape part of the apparatus has a similar construction to that of the tab part. The tape part also has a general triangular configuration with opposite top and bottom surfaces. A magnet is contained in the tape part between the top and bottom surfaces 
         [0012]    First and second blocks project outwardly from the tape part bottom surface. The first and second blocks are oriented at a right angle on the tape part bottom surface. The blocks have respective first and second surfaces that oppose each other. The first and second side surfaces define a right angle between the surfaces. 
         [0013]    A tape post projects outwardly from the tape part top surface. Like the post of the tab part, the tape post is rotatable about a rotation axis and is positioned on the tape part top surface directly opposite the apex of the right angle formed by the first and second side surfaces of the blocks on the tape part bottom surface. The tape part post has a recessed, curved surface formed in the top of the post. The curved surface is dimensioned to receive the tape of a tape measure on the surface. A pair of indicator grooves are formed in the tape post top surface on opposite sides of the curved surface. The pair of indicator grooves are on a line that intersects the tape post rotation axis. 
         [0014]    The method of using the apparatus to confirm the right angles of the corners of a rectangular structure with a tape measure first involves positioning the tab part and the tape part of the apparatus over first and second diagonally opposite corners of the structure. For example, the tab part of the apparatus is positioned over a first corner of the structure with the bottom surface of the tab part engaging over the corner and the block side surfaces of the tab part engaging against opposite sides of the corner of the structure. The tape part is then positioned over the diagonally opposite second corner of the structure with the bottom surface of the tape part engaging over the corner and the side surfaces of the tape part engaging against the opposite sides of the corner of the structure. When the structure is constructed of metal, the magnets in the two parts of the apparatus hold them to the corners of the structure. When the apparatus is used on a structure of non-ferris material the magnets can be replaced with suction cups, clamps or other equivalent devices. 
         [0015]    The tab of the tape measure is then positioned in the notch in the tab part post. The tape of the tape measure is extended from the tape measure housing across the rectangular structure to the tape part at the diagonally opposite corner of the structure. The tape of the tape measure is then positioned over the tape part adjacent the indicator on the tape part post and a distance measurement diagonally across the rectangular structure is determined from observing the measurement on the tape measure tape adjacent the indicator. 
         [0016]    The tab part and the tape part are then moved to the other diagonally opposite corners of the rectangular structure and the measurement method is repeated. The two diagonal distance measurements are then compared to confirm the right angles of the rectangular structure. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0017]    Further features of the apparatus and method of the invention are set forth in the following detailed description of the apparatus and method and in the drawing figures. 
           [0018]      FIG. 1  is a plan view of the tab part and the tape part of the apparatus. 
           [0019]      FIG. 2  is a side elevation view of one side of the tab part from along the line  2 - 2  in  FIG. 1 . 
           [0020]      FIG. 3  is a side elevation view of one side of the tape part from along the line  3 - 3  in  FIG. 1 . 
           [0021]      FIG. 4  is a view of the tab part similar to  FIG. 1 , but also shows internal features in dashed lines. 
           [0022]      FIG. 5  is a view of the tape part similar to  FIG. 1 , but also shows internal features in dashed lines. 
           [0023]      FIG. 6  is a view of the side of the tab part similar to  FIG. 2 , but also shows internal features in dashed lines. 
           [0024]      FIG. 7  is a view of the side of the tape part similar to  FIG. 3 , but also shows internal features in dashed lines. 
       
    
    
     DETAILED DESCRIPTION 
       [0025]    As stated earlier, the apparatus of the invention  10  is basically a two part tool comprising a tab part  12  that is used with the tab at the end of the tape of a conventional tape measure, and a tape part  14  that is used with the tape of the conventional tape measure. In the example of the apparatus  10  to be described, both the tab part  12  and the tape part  14  are constructed of metal. This gives the two parts of the apparatus sufficient strength to be used in confirming right angles at corners of a rectangular structure constructed of metal. Other embodiments of the apparatus  10  could be constructed of other materials. 
         [0026]    As shown in  FIGS. 1 and 4 , the tab part  12  of the apparatus  10  includes a base  16  having a general triangular configuration with opposite top  18  and bottom  20  surfaces. The top  18  and bottom  20  surfaces are flat, parallel surfaces. The base  16  has two intersecting side surfaces  22 ,  24  that are oriented at a right angle to each other. The intersecting side surfaces  22 ,  24  have substantially the same length. The base also has a couple of shorter side surfaces  26 ,  28  and a longer side surface  30  that extends between the shorter side surfaces. The side surfaces of the base  16  give the base its general triangular configuration. However, it is not necessary that the base  16  have the triangular configuration shown in  FIGS. 1 and 4  for proper functioning of the tab part  12 . 
         [0027]    As shown in  FIGS. 4 and 6 , a cylindrical hole  32  is formed in the base bottom surface  20 . The hole  32  extends upwardly through the bottom surface  20  and into the base  16 , but does not extend completely through the base. The hole  32  is located in a central area of the tab part base  16 . 
         [0028]    A cylindrical magnet  34  is positioned in the hole  32  in the base bottom surface  20 . The magnet  34  is dimensioned to occupy much of the interior volume of the hole  32  in the base. 
         [0029]    Referring to  FIGS. 1 ,  2 ,  4  and  6 , a plate  36  is secured to the tab part  16 . The plate  36  has a triangular portion  38  that extends over the base bottom surface  20  and the hole  32  in the bottom surface and secures the magnet  34  in the hole. The configuration of the plate triangular portion  38  closely follows the triangular configuration of the base bottom surface  20 . The plate  36  also has an elongate flange  40  that is oriented at a right angle to the plate triangular portion  38 . The flange  40  extends across the longer side surface  30  of the base  16  and is secured to the side surface by a pair of threaded fasteners  42 . 
         [0030]    A pair of the elongate blocks  44 ,  46  are secured to the base bottom surface  20  along the intersecting side surfaces  22 ,  24  of the base. Each of the elongate blocks  44 ,  46  has a rectangular configuration except for a notch  48 ,  50  formed in a bottom surface of each block. The opposite top surface of each block  44 ,  46  is positioned against the plate triangular portion  38  on the base bottom surface  20  and the blocks  44 ,  46  are secured to the base bottom surface  20  by pairs of threaded fasteners  52 ,  54 . The fasteners  52 ,  54  and their respective blocks  44 ,  46  thereby further secure the plate  36  to the tab part base  16 . The blocks  44 ,  46  have flat interior surfaces  56 ,  58  that oppose each other. The interior surfaces  56 ,  58  define a right angle between the surfaces having an apex  60 . Coplanar straight lines projected across the block interior surfaces  56 ,  58  intersect at the apex point  60  shown in  FIG. 4 . 
         [0031]    Referring to  FIGS. 1 ,  2 ,  4  and  6 , a cylindrical tab post  64  projects outwardly from the base top surface  18 . As shown in  FIG. 7 , the tab post  64  is mounted for rotation on the base top surface  18  by a stub shaft  66  that extends downwardly through a hole formed in the base top surface. The stub shaft  66  extends through a smaller diameter portion of the hole to a larger diameter portion of the hole. A retaining ring  68  mounted on the stub shaft  66  in the larger internal diameter portion of the hole secures the tab post  64  to the base top surface  18 . The tab post  64  is rotatable on the base top surface  18  about a rotation axis that intersects the apex  60  of the angle formed between the block interior surfaces  56 ,  58  on the bottom surface  20  of the base. Referring to  FIGS. 1 ,  2 ,  4  and  6 , the tab post  64  projects outwardly from the base top surface  18  to a top surface  70  of the post. A notch or groove  72  is formed in the post top surface. The notch  72  has an edge  74  that is positioned in a plane that intersects the axis of rotation of the tab post  64  and the apex  60  of the right angle formed by the first and second blocks  44 ,  46  on the base bottom surface  20 . The notch  72  is dimensioned to receive a tape measure tab inserted in the notch. A spring biased detent  76  is provided on the tab post  64  on the opposite side of the notch  72  from the notch edge surface  74 . When a tape measure tab is inserted in the notch  72  the tab compresses the spring of the detent  76  and the spring force exerted on the detent holds the tab against the edge surface  74  and in the notch  72 . 
         [0032]    A pair of studs  78  are inserted into holes in the base top surface  18  and project outwardly from the top surface. The studs  78  are positioned equal distances from the tab post  64  and are directly above the interior surfaces  56 ,  58  of the first  44  and second  46  blocks secured to the base bottom surface  20 . A pin  80  is inserted into a hole formed in the side of the tab post  64 . The pin  80  projects outwardly from the tab post parallel over the base top surface  18 . The pin  80  has a center axis that intersects the tab post  64  axis of rotation. The pin  80  projects a sufficient distance from the tab post  64  to engage with one of the pair of studs  78  when the tab post  64  is rotated in opposite directions on the tab part base  16 . Thus, the pair of studs  78  limit the rotation of the tab post  64  to a 90° arc. 
         [0033]    The tape part  14  has a construction that, for the most part, is the same as that of the tab part  12 . Therefore, the construction of the tape part  14  that is the same as the tab part  12  will not be described in detail, and the component parts of the tape part  14  that are the same as those of the tab part  12  will be labeled with the same reference numbers employed in the description of the tab part  12  with the reference numbers being followed by a prime (′). 
         [0034]    Referring to  FIGS. 1 ,  3 ,  5  and  7 , the tape part  14  also has a base  16 ′ with a general triangular configuration and flat, parallel top  18 ′ and bottom  20 ′ surfaces. The tape part base  16 ′ also has a pair of intersecting side surfaces  22 ′,  24 ′, a pair of shorter side surfaces  26 ′,  28 ′ and a longer side surface  30 ′. As shown in  FIGS. 5 and 7 , a cylindrical hole  32 ′ extends into the tape part bottom surface  20 ′ and a cylindrical magnet  34 ′ is positioned in the hole. 
         [0035]    Referring to  FIGS. 1 ,  3 ,  5  and  7 , a plate  36 ′ is secured to the tape part bottom surface  20 ′ with a triangular portion  38 ′ of the plate extending over the bottom surface  20 ′ and securing the magnet  34 ′ in the hole  32 ′, and with a flange  40 ′ of the plate extending over the longer side surface  30 ′ of the base. A pair of fasteners  42 ′ secure the flange  40 ′ to the longer side surface  30 ′ of the base  16 ′. 
         [0036]    First  44 ′ and second  46 ′ elongate blocks are secured to the base bottom surface  20 ′. Just as with the tab part  12 , the blocks  44 ′,  46 ′ have notches  48 ′,  50 ′ in their bottom surfaces and are secured to the tape part base  16 ′ by a pair of fasteners  52 ′,  54 ′. The blocks  44 ′,  46 ′ also function to secure the plate  36 ′ to the base bottom surface  20 ′. Interior surfaces  56 ′,  58 ′ of the first  44 ′ and second  46 ′ blocks define a right angle between the surfaces. Straight, coplanar lines extended across the surfaces  56 ′,  58 ′ intersect at an apex point  60 ′ shown in  FIG. 5 . 
         [0037]    Referring to  FIGS. 1 ,  3 ,  5  and  7 , the tape part  14  also includes a cylindrical tape post  64 ′ that is mounted for rotation on the top surface  18 ′ of the tape part base  16 ′. As shown in  FIG. 7 , the tape post  64 ′ has a stub shaft  66 ′ that is inserted into a hole formed in the base top surface  18 ′ and is secured in the hole by a retainer ring  68 ′. The tape post  64 ′ projects outwardly from the top surface  18 ′ of the tape part base  16 ′ to a top surface  70 ′ of the post. 
         [0038]    The tape part  14  of the apparatus differs from the tab part  12  in the construction of the top surface  70 ′ of the tape post  64 ′. The tape post top surface  70 ′ is formed with a recessed curved surface  82 . The curved surface  82  at the top of the tape post  54 ′ is dimensioned to match the cross-section curvature of the tape of a conventional tape measure. A pair of collinear indicator grooves  84  are formed in the tape post top surface  70 ′ on opposite sides of the curved surface  82 . A straight line extending through the pair of indicator grooves  84  intersects the axis of rotation of the tape post  64 ′ and the apex  60 ′ of the right angle defined by the interior surfaces  56 ′,  58 ′ of the first  44 ′ and second  46 ′ blocks on the bottom surface of the tape part base  16 ′. 
         [0039]    The method of using the apparatus  10  to confirm the right angles of the corners of a rectangular structure with a tape measure first involves positioning the tab part  12  and the tape part  14  of the apparatus over first and second diagonally opposite corners of the structure. For example, the tab part  12  of the apparatus is positioned over a first corner of the structure with the bottom surface  20  of the tab part  12  engaging over the corner and the interior surfaces  56 ,  58  of the first  44  and second  46  blocks of the tab part  12  engaging against opposite sides of the corner of the structure. This positions the edge surface  74  on the tab part post  64  directly over the apex of the structure first corner. The tape part  14  is then positioned over the diagonally opposite corner of the structure with the bottom surface  20 ′ of the tape part engaging over the corner and the interior surfaces  56 ′,  58 ′ of the first  44 ′ and second  46 ′ blocks on the tape part bottom surface  20 ′ engaging against the opposite sides of the second corner of the structure. This positions the line between the indicator grooves  84  on the tape part post  64 ′ directly over the apex of the structure second corner. When the structure is constructed of metal, the magnets  34 ,  34 ′ in the respective tab part  12  and tape part  14  hold them to the corners of the structure. In use with non-ferris materials, the magnets could be replaced with suction cups, clamps or other equivalent devices. 
         [0040]    The tab of the tape measure is then positioned in the notch  72  in the top surface  70  of the tab part post  64 . The detent  76  urges the tab part of the tape measure against the edge surface  74  of the notch and securely holds the tab of the tape measure in the notch  72 . The tape of the tape measure is then extended from the tape measure housing across the structure to the tape part  14  of the apparatus at the diagonally opposite second corner of the structure. The ability of the tab part post  64  to rotate assists in securing the tape measure tab in the post notch  72  as the tape measure is moved to the second corner. The tape of the tape measure is then positioned over the recessed curved surface  82  in the top of the tape part post  64 ′. A distance measurement diagonally across the rectangular structure from the first corner apex to the second corner apex is determined from observing the measurement on the tape measure tape between the indicator grooves  84  on the tape part post  64 ′. 
         [0041]    The tab part  12  and the tape part  14  are then moved to the other diagonally opposite third and fourth corners of the rectangular structure and the measurement method described above is repeated. The two diagonal distance measurements between the first and second corners and the third and fourth corners of the structure are then compared to see if they are equal and to thereby confirm the right angles at the corners of the rectangular structure. 
         [0042]    As various modifications could be made in the construction of the invention herein described and illustrated without departing from the scope of the invention, it is intended that all matter contained in the foregoing description or shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.