Abstract:
A coupler nut with multiple bore diameters that are symmetrically stepped in both directions away from the center bore diameter. The bore diameter at the center is the smallest, and each pair of steps away from the center bore increases the bore diameter. This means that the coupler nut has no single, correct vertical orientation. It has no top or bottom, and as such is vertically ambidextrous.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to in-line joining of threaded rods in building construction. The rods can be “all thread” rods that are simply lengths of threaded rod, usually steel, bolts (e.g., anchor bolts that are embedded in concrete foundations), and combinations of the two. Holdown systems that link a series of threaded rods, from an anchor bolt through one or more threaded rods, are commonly used to secure a light frame building to the foundation walls or slab in high wind or earthquake prone regions. The anchor bolts pass from the concrete through holes in the mudsill, where they are typically tied to walls posts using holdown connectors. The threaded rods are connected with coupler nuts to the anchor bolts, and to each other in sequence with coupler nuts. The threaded rods pass through holes in the wall top plates up through the top story of the building, usually being secured at the bottom of each story and directly above the highest top plate. Because the uplift load reduces with elevation, the size of the threaded rods can also be reduced. For this reason, coupler nuts that allow one to connect threaded rods of different diameters are desirable. Coupler nuts that have two inner bore diameters are well-known, but these can only work in one orientation with respect to the connected rods. Furthermore, they can connect only two rods of two specific diameters that match the inner bore diameters of the coupler nut. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention improves on this prior art by providing a coupler nut with multiple bore diameters that are symmetrically stepped in both directions away from the center bore diameter. The bore diameter at the center is the smallest, and each pair of steps away from the center bore increases the bore diameter. This means that the coupler nut has no single, correct vertical orientation. It has no top or bottom, and as such is vertically ambidextrous. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is a side elevation view of an embodiment of the connection of the present invention. 
         FIG. 2  is a side elevation view of an embodiment of the connector of the present invention. 
         FIG. 3  is a plan view of an embodiment of the connector of the present invention. 
         FIG. 4A  is a cross-sectional elevation view of an embodiment of the connector of the present invention taken along line  4 A- 4 A in  FIG. 2 . 
         FIG. 4B  is a cross-sectional elevation view of an embodiment of the connector of the present invention. 
         FIG. 5  is a cross-sectional plan view of an embodiment of the connector of the present invention taken along line  5 - 5  in  FIG. 2 . 
         FIG. 6A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a second diameter in a second portion and the second threaded rod member is threaded into a third diameter in a third portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 6B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a second diameter in a second portion and the second threaded rod member is threaded into a third diameter in a third portion of an embodiment of the connector of the present invention. 
         FIG. 7A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is threaded into a second diameter in a second portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 7B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is threaded into a second diameter in a second portion of an embodiment of the connector of the present invention. 
         FIG. 8A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is threaded into a second diameter in a second portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 8B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is threaded into a third diameter in a third portion of an embodiment of the connector of the present invention. 
         FIG. 9A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a third diameter in a third portion and the second threaded rod member is threaded into the other third diameter in the other third portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 9B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a third diameter in a third portion and the second threaded rod member is threaded into the other third diameter in the other third portion of an embodiment of the connector of the present invention. 
         FIG. 10A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a second diameter in a second portion and the second threaded rod member is threaded into the other second diameter in the other second portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 10B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a second diameter in a second portion and the second threaded rod member is threaded into the other second diameter in the other second portion of an embodiment of the connector of the present invention. 
         FIG. 11A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is also threaded into the first diameter in the first portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 11B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is also threaded into the first diameter in the first portion of an embodiment of the connector of the present invention. 
         FIG. 12  is a side elevation view of an embodiment of the connector of the present invention. 
         FIG. 13  is a plan view of an embodiment of the connector of the present invention. 
         FIG. 14A  is a cross-sectional elevation view of an embodiment of the connector of the present invention taken along line  14 A- 14 A in  FIG. 12 , showing reverse threading. 
         FIG. 14B  is a cross-sectional elevation view of an embodiment of the connector of the present invention. 
         FIG. 15  is a cross-sectional plan view of an embodiment of the connector of the present invention taken along line  15 - 15  in  FIG. 12 . 
         FIG. 16A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is threaded into a second diameter in a second portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 16B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is threaded into a second diameter in a second portion of an embodiment of the connector of the present invention. 
         FIG. 17A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a second diameter in a second portion and the second threaded rod member is threaded into the other second diameter in the other second portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 17B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into a second diameter in a second portion and the second threaded rod member is threaded into the other second diameter in the other second portion of an embodiment of the connector of the present invention. 
         FIG. 18A  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is also threaded into the first diameter in the first portion of an embodiment of the connector of the present invention, showing reverse threading. 
         FIG. 18B  is a cross-sectional elevation view of an embodiment of the connection of the present invention, in which the first threaded rod member is threaded into the first diameter in the first portion and the second threaded rod member is also threaded into the first diameter in the first portion of an embodiment of the connector of the present invention. 
         FIG. 19  is a side elevation view of an embodiment of the connector of the present invention. 
         FIG. 19A  is a cross-sectional elevation view of an embodiment of the connector of the present invention taken along line  19 A- 19 A in  FIG. 19 , showing reverse threading. 
         FIG. 19B  is a cross-sectional plan view of an embodiment of the connector of the present invention. 
         FIG. 20  is a side elevation view of an embodiment of the connector of the present invention. 
         FIG. 20A  is a cross-sectional elevation view of an embodiment of the connector of the present invention taken along line  20 A- 20 A in  FIG. 20 , showing reverse threading. 
         FIG. 20B  is a cross-sectional plan view of an embodiment of the connector of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     As shown in  FIG. 14A , the present invention is a coupler nut  1  with a first internal bore  2 . The coupler nut  1  has a first outer wall  3 , a first end  4 , and a second end  5 . The first internal bore  2  opens to the first end  4  and the second end  5 . The first internal bore  2  has a first diameter  6  that occupies a first portion  7  of the first internal bore  2 . Preferably, the first diameter  6  and the first portion  7  will be centered in the internal bore  2 . The first internal bore  2  also has a pair of second diameters  8 . The second diameters  8  at least partially occupy a pair of second portions  9  of the first internal bore  2 . The second diameters  8  are greater than the first diameter  6 . One of the said second diameters  8  is between the first diameter  6  and the first end  4 . The other of the second diameters  8  is between the first diameter  6  and the second end  5 . Preferably, the second diameters  8  are equal. Preferably, the first diameter  6  is ⅝″ and the first portion is at least ⅝″ long. Preferably, the second diameters  8  are ⅞″ and the second portions  9  are at least ⅞″ long. Preferably, the first and second ends  4  and  5  are chamfered, with a chamfer height of 0.083″. 
     As shown in  FIG. 4A , in another preferred embodiment, the first internal bore  2  has a pair of third diameters  10  that at least partially occupy a pair of third portions  11  of the first internal bore  2 . The third diameters  10  are greater than the second diameters  8 . One of the third diameters  10  is between one of the second diameters  8  and the first end  4 . The other of the third diameters  10  is between the other of the second diameters  8  and the second end  5 . Preferably, the third diameters  10  are equal. Preferably, the third diameters  10  are 1⅛″ and the third portions  11  are at least 1⅛″ long. 
     As shown in  FIG. 4A  and FIG.  14 SA, preferably the first internal bore  2  is at least partially threaded with one or more threads  12 . The threads  12  can be single, double or more, but single is preferred. The threads  12  can reverse, preferably in the middle of the first internal bore  2 , but more preferably the threads are  12  are not reversed. Reversed threads  12  would permit the coupler nut  1  to draw together two similarly reverse-threaded objects, but that is not the preferred embodiment because reverse-threaded objects are not interchangeable and are consequently difficult to use. Preferably, the first diameter  6  is at least partially threaded with one or more threads  12 . Also, the second diameters  8  are preferably at least partially threaded with one or more threads  12 . If there are third diameters  10 , the third diameters  10  are preferably at least partially threaded with one or more threads  12 . In the preferred embodiment, all of the first internal bore  2  is threaded, but it is possible to have unthreaded portions so long as there are sufficient threads  12  to achieve the necessary connection to the joined threaded objects. Unthreaded portions could be anywhere within or at the junctures between the different diameters. Preferably, the thread pitch is  11  in the first diameter  6 ,  9  in the second diameters  8 , and  7  in the third diameters  10 . Preferably, the threads are ASME B1.1 UNC Class 2B. 
     As shown in  FIG. 2  and  FIG. 4A , the first outer wall  3  preferably has at least one opening  13  that opens to the first internal bore  2 . The opening allows one to check to see whether, and how far, an object has been threaded into the first internal bore  2 . Preferably, the first outer wall  3  has at least one opening  13  that opens to the first diameter  6  and at least one opening  13  that opens to each of the second diameters  8 , for a total of at least three openings  13 . If there are third diameters  8 , the first outer wall  3  preferably has at least one opening  13  that opens to the first diameter  6 , at least one opening  13  that openings to each of the second diameters  8 , and at least one opening  13  that opens to each of the third diameters  8 , for a total of at least five openings  13 . Preferably, the openings  13  are 0.187″ in diameter and/or 0.25″ in diameter. 
     Preferably, the first outer wall  3  has a circumference  14  that is at least partially hexagonal, defining six substantially flat faces  15 . Nuts conventionally have either a hexagonal circumference  14 , or a square circumference  14 , allowing them to be gripped and turned with wrenches. Conventionally, only smaller nuts have a square circumference  14 , as the excess material with a larger nut would disadvantageously add both materials cost and weight. Preferably, the coupler nut  1  is made from ASTM A563 GRADE B steel. Preferably, it is lathe-cut. 
     As shown in  FIG. 16A , the present invention is also the coupler nut  1  connection  101  between a first threaded rod member  102  and a second threaded rod member  103 . The coupler nut  1  preferably has a first internal bore  2 , a first outer wall  3 , a first end  4 , and a second end  5 . The first internal bore  2  preferably has a first diameter  6  that occupies a first portion  7  of the first internal bore  2 . Preferably, the first internal bore  2  has a pair of second diameters  8  that at least partially occupy a pair of second portions  9  of the first internal bore  2 . The second diameters  8  are preferably greater than the first diameter  6 . Preferably, one of the second diameters  8  is between the first diameter  6  and the first end  4 . Preferably, the other of the second diameters  8  is between the first diameter  6  and the second end  5 . The first threaded rod member  102  preferably has a first threaded end  104 , and the first threaded end  104  is threaded into the first internal bore  2  through the first end  4  of the coupler nut. Preferably, the second threaded rod member  103  has a first threaded end  105 , and the first threaded end  105  is threaded into the first internal bore  2  through the second end  5  of the coupler nut  1 . The threaded rod members  102  and  103  can be all-thread rod, bolts, anchor bolts, holdowns, or any combination of these and other threaded rod members  102  and  103 . 
     The basic purpose of the present invention is to allow threaded rod members  102  and  103  of different matching, and different non-matching, sizes to be connected by a single multiuse coupler nut  1 . 
     In a preferred embodiment of the connection  101 , the first threaded end  104  of the first threaded rod member  102  is threaded into the first diameter  6  of the coupler nut  1 . The first threaded end  105  of the second threaded rod member  103  is threaded into the first diameter  6  of the coupler nut  1 . 
     In a further preferred embodiment of the connection  101 , the first threaded end  104  of the first threaded rod member  102  is threaded into the first diameter  6  of the coupler nut  1 . The first threaded end  105  of the second threaded rod member  103  is threaded into one of the second diameters  8  of the coupler nut  1 . 
     In a still further preferred embodiment of the connection  101 , the first threaded end  104  of the first threaded rod member  102  is threaded into one of the second diameters  8  of the coupler nut  1 . The first threaded end  105  of the second threaded rod member  103  is threaded into the other of the second diameters  8  of the coupler nut  1 . 
     In another preferred embodiment of the connection  101 , the first internal bore  2  has a pair of third diameters  10  that at least partially occupy a pair of third portions  11  of the first internal bore  2 . The third diameters  10  are greater than the second diameters  8 . One of the third diameters  10  is between one of the second diameters  8  and the first end  4 , and one of the third diameters  10  is between the other of the second diameters  8  and the second end  5 . 
     In a further preferred embodiment of the connection  101 , the first threaded end  104  of the first threaded rod member  102  is threaded into the first diameter  6  of the coupler nut  1 . The first threaded end  105  of the second threaded rod member  103  is threaded into one of the third diameters  10  of said coupler nut  1 . 
     In a still further preferred embodiment of the connection  101 , the first threaded end  104  of the first threaded rod member  102  is threaded into one of the second diameters  8  of the coupler nut  1 . The first threaded end  105  of the second threaded rod member  103  is threaded into one of the third diameters  10  of the coupler nut  1 . 
     In a still further preferred embodiment of the connection  101 , the first threaded end  104  of the first threaded rod member  102  is threaded into one of the third diameters  10  of the coupler nut  1 . The first threaded end  105  of the second threaded rod member  103  is threaded into the other of the third diameters  10  of the coupler nut  1 . 
     Two sizes of an alternate preferred embodiment of the coupler nut  1  are shown in drawing  FIGS. 19-20B . In this embodiment, the majority of the first outer wall  3  is round rather than hexagonal in circumference. Instead of six flat faces  15 , the outer wall  3  has two flat-faced indented portions  16  midway between the first end  4  and the second end  5 . These provide purchase for a wrench. 
     In the smaller of the two sizes of this alternate preferred embodiment, the total height of the coupler nut  1 , measured from the first end  4  to the second end  5 , is 3.750 inches. There are eight circular openings  13  lined up in two opposing lines of four openings  13  each in the outer wall  3 . These openings  13  are drilled and are 0.250 inches in diameter. The distance from the first end  4  to the center of the nearest pair of openings  13  is 0.850 inches; the distance from the first end  4  to the center of the next nearest pair of openings  13  is 1.600 inches. Likewise, the distance from the second end  5  to the center of the nearest pair of openings  13  is 0.850 inches; the distance from the second end  5  to the center of the next nearest pair of openings  13  is 1.600 inches. The distance from the first end  4  and the second end to the indented portions  16  is 1.562 inches. The distance between the two indented portions  16  is 1.015 inches. The outer diameter of the coupler nut  1  is 1.250 inches. The juncture  17  between the first outer wall  3  and the first end  4  is rounded with a radius of 0.100 inches; the juncture  18  between the first outer wall  3  and the second end  5  is rounded with a radius of 0.100 inches. The first diameter  6  is nominally 0.547 inches. The second diameters  8  are nominally 0.780 inches. The second diameters  8  are drilled to a depth of 1.000 inches. The distance between the second diameters  8 , and the depth of the first diameter  6 , is 1.750 inches. The depth of the threads  12  of the second diameters  8  is 0.990 inches. The threads  12  of the first diameter  6  is split into two portions each having a depth of 0.812 inches, separated by an unthreaded portion of 0.026 inches. The threads  12  of the second diameters  8  are ⅞-9 UNC-1B. The threads  12  of the first diameter  6  are ⅝-11 UNC-1B. 
     In the larger of the two sizes of this alternate preferred embodiment, the total height of the coupler nut  1 , measured from the first end  4  to the second end  5 , is 4.500 inches. There are eight circular openings  13  lined up in two opposing lines of four openings  13  each in the outer wall  3 . These openings  13  are drilled and are 0.250 inches in diameter. The distance from the first end  4  to the center of the nearest pair of openings  13  is 1.090 inches; the distance from the first end  4  to the center of the next nearest pair of openings  13  is 1.950 inches. Likewise, the distance from the second end  5  to the center of the nearest pair of openings  13  is 1.090 inches; the distance from the second end  5  to the center of the next nearest pair of openings  13  is 1.950 inches. The distance from the first end  4  and the second end to the indented portions  16  is 1.938 inches. The distance between the two indented portions  16  is 1.265 inches. The outer diameter of the coupler nut  1  is 1.500 inches. The juncture  17  between the first outer wall  3  and the first end  4  is rounded with a radius of 0.100 inches; the juncture  18  between the first outer wall  3  and the second end  5  is rounded with a radius of 0.100 inches. The first diameter  6  is nominally 0.781 inches. The second diameters  8  are nominally 0.980 inches. The second diameters  8  are drilled to a depth of 1.250 inches. The distance between the second diameters  8 , and the depth of the first diameter  6 , is 2.000 inches. The depth of the threads  12  of the second diameters  8  is 1.240 inches. The threads  12  of the first diameter  6  is split into two portions each having a depth of 0.975 inches, separated by an unthreaded portion of 0.050 inches. The threads  12  of the second diameters  8  are 1⅛-7 UNC-1B. The threads  12  of the first diameter  6  are ⅞-9 UNC-1B. 
     Number List 
       1 . coupler nut 
       2 . first internal bore (of  1 ) 
       3 . first outer wall (of  1 ) 
       4 . first end (of  1 ) 
       5 . second end (of  1 ) 
       6 . first diameter (of  2 ) 
       7 . first portion (of  2 ) 
       8 . second diameters (of  2 ) 
       9 . second portions (of  2 ) 
       10 . third diameters (of  2 ) 
       11 . third portions (of  2 ) 
       12 . threads (of  2 ,  6 ,  8  and/or  10 ) 
       13 . opening (of  3 ) 
       14 . circumference (of  3 ) 
       15 . flat faces (of  3 ) 
       16 . flat-faced indents (of  1 ) 
       17 . juncture (between  3  and  4 ) 
       18 . juncture (between  3  and  5 ) 
       101 . connection 
       102 . first threaded rod member 
       103 . second threaded rod member 
       104 . first threaded end (of  102 ) 
       105 . first threaded end (of  103 )