Patent Publication Number: US-6664937-B2

Title: Two-axis pole mount assembly

Description:
RELATED APPLICATIONS 
     This application claims the priority of U.S. provisional patent application Serial No. 60/297,452 entitled “Two-Axis Pole Mounting Assembly” filed Jun. 13, 2001. 
    
    
     BACKGROUND OF THE INVENTION 
     The present invention relates to telecommunications systems and more particularly to a mounting assembly for mounting a telecommunications radio to a support. 
     Mounting assemblies for mounting radios or antennas to outdoor support structures such as poles are well known in the telecommunications industry. The mounting assemblies generally include means for adjusting the radio or antenna both in elevation and azimuth in order to properly align the radio or antenna. Typically these assemblies contain a single component upon which both the elevational and azimuthal adjustments are made. As both axes are adjusted at the same pivoting point, they are not independent of each other. This is disadvantageous in that adjustment of one axis will interfere with the adjustment of the other axis. This requires the technician to repeatedly retune the adjustments. 
     Another problem with current mount assemblies is that they do not provide for a solid locking geometry. Rather, once the axial adjustments have been made, there is still some looseness in the joints of the mount assembly, which results in a need for frequent readjustment. 
     An improved mount assembly is needed. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a pictorial representation of the radio mounting assembly mounted to a pole, according to one embodiment of the present invention. 
     FIG. 2 is an exploded pictorial view of the mounting assembly and bracing system from the front thereof. 
     FIG. 3 is a pictorial representation of the base and azimuthal adjustment component of the mounting assembly including the triangles from which the screw extension length can be determined. 
     FIG. 4 is a pictorial representation of the azimuthal adjustment component and elevational adjustment component of the mounting assembly including the triangles from which the screw extension length can be determined. 
     FIGS. 5 and 6 illustrate the trigonomic triangles shown in FIG. 3 used to determine the screw extension length as a function of the rotation angle. 
     FIGS. 7 and 8 illustrate the trigonomic triangles shown in FIG. 4 used to determine the screw extension length as a function of the rotation angle. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     U.S. Provisional Patent Application No. 60/297,452, filed Jun. 13, 2001 is incorporated by reference herein in its entirety. 
     Referring to FIGS. 1 and 2, a radio mounting assembly  100  is shown mounted to a pole  10 . The mounting assembly  100  is braced to the pole  10  via bracing system  5  which includes braces  6 , brace fasteners (e.g. bolts)  7  and nuts  8 . Although shown attached to a pole  10 , it should be understood that the mounting assembly  100  described herein may be coupled to any number of support structures. As illustrated, a base  110  has planar surfaces  122  and mounting holes  120  that allow it to be attached to any substantially planar surface, such as a wall, roof or the like. Additionally, or alternatively, base  110  may include various mounting holes, clips, ridges or the like in order to easily attach to a number of structures, such as walls, roofs, or the like. Moreover, various adaptations or configurations of base  110  may be provided for coupling to a support structure depending on the particular support structure to be associated therewith. For example, instead of a planar surface  122 , any contour may be used to accommodate the shape of a surface to which the base  110  is mounted. 
     Mounting assembly  100  comprises base  110 , an azimuthal (horizontal) adjustment component  130  and an elevational (vertical) adjustment component  150 . According to one exemplary embodiment (as shown in FIGS.  1  and  2 ), the azimuthal adjustment component  130  is directly attached to the base  110  and the elevational adjustment component  150  is directly attached to the azimuthal adjustment component  130 . Alternatively, the elevational adjustment component  150  could be directly attached to the base  110  and the azimuthal adjustment component  130  directly attached to the elevational adjustment component  150 . 
     Exemplary base  110  comprises a support base  111 , adjustment component supports  112  and  114 , pivot holes  116  providing a pivot axis, a contact plate  118 , mounting holes  120  and rear surfaces  122 . Support base  111  and mounting holes  120  provide for attachment to a variety of support structures as described above. Adjustment supports  112  and  114  and pivot holes  116  allow for attachment of a first adjustment component. In this example, the first adjustment component is the azimuthal adjustment component  130  and a second adjustment component (attached to the first adjustment component) is the elevational adjustment component  150 . Mounting holes  120  allow for attachment of the mounting assembly  100  to a variety of support structures as set forth above. 
     The contact plate  118  of the base  110 , shown in the figures as a semi-circular protrusion of the adjustment component support  112 , has a center point  119  which is eccentrically located from the pivot axis (see FIG. 3) in holes  116 . Although shown as an extension of adjustment component support  112 , the contact plate  118  may be located at a variety of locations on the base  110  including locations separate from adjustment component supports  112  or  114 . 
     Further, although preferred embodiments of the contact plate  118  include a circular profile, other profiles may be substituted on the contact plate. For example, the contact plate may have an elliptical, paralobolic, hyperbolic or flat profile. Also, a ridge or frame may be employed rather than a solid plate. 
     The exemplary azimuthal adjustment component  130  includes two adjustment members, which may be, for example, screws or bolts  132 , two adjustment holes  133 , adjustment component supports  134 , first pivot holes  136  providing a pivot axis for the elevational adjustment component  150 , a contact plate  138 , at least one pivot member (e.g., screws or pins)  140  and second pivot holes  142  providing a pivot axis for adjustment of the azimuthal adjustment component  130 . The azimuthal adjustment component  130  is pivotally coupled to the base  110  by the at least one pivot pin or screw  140 . The pivot screws (or screw)  140  are inserted through the respective second pivot holes  142  of the azimuthal adjustment component and screwed (or otherwise inserted) into the pivot holes  116  of the base  110 . The second pivot holes  142  should be slightly larger in diameter than the pivot screws  140  to allow for free azimuthal rotation of the azimuthal adjustment component  130  relative to the base  110 . Although shown in the figures as having two pivot screws, it should be appreciated that the azimuthal adjustment component may have one pivot pin or screw which passes through both pivot holes  116  of the base  110 . Also, the pivotal mount may comprise any of a number of different fastener types, including bolts, rods, pins, bearings or the like. 
     Adjustment component supports  134  and first pivot holes  136  allow for attachment of the elevational adjustment component  150 . The contact plate  138  of the azimuthal adjustment component  130 , shown in the figures as a semi-circular protrusion between the adjustment component supports  134 , has a center point  139  which is eccentrically located from the pivot axis in holes  136  of the adjustment component supports  134  (see FIG.  4 ). Although shown between adjustment component supports  134 , the circular profile  138  may be located at alternative locations on the azimuthal adjustment component  130  including as an extension of one of the adjustment component supports  134  similar to the location of the circular profile  118  on the base  110 . Further, although preferred embodiments of the contact plate  138  include a circular profile, other profiles may be substituted on the contact plate. For example, the contact plate may have an elliptical, paralobolic, hyperbolic or flat profiles. Also, a ridge or frame may be employed rather than a solid plate. 
     Adjustment screws  132  are inserted through adjustment holes  133  and interface with the circular profile of contact plate  118  on the base  110  when the azimuthal adjustment component  130  is in a locked position. The adjustment screws  132  allow for both azimuthal adjustment of the azimuthal adjustment component  130  and solid locking of the azimuthal adjustment component  130  into a desired location as is more fully described below. Preferably, the range of rotation for the azimuthal adjustment component  130  from vertical is at least +/−30°. 
     Although preferred adjustment members are screws  132 , other types of adjustment members may be substituted. For example, any pin that is capable of being locked may be used. A pin may be locked using a set screw, a cotter pin, or the like. 
     Elevational adjustment component  150  comprises two adjustment members  152  (e.g., screws or pins), two adjustment holes  153 , at least one pivot member  154  (e.g., screws or pins), pivot holes  155 , a hanger element  156  and a plurality of mounting holes  158 . The elevational adjustment component  150  is pivotally coupled to the azimuthal adjustment component  130  by the at least one pivot member  154 . The pivot members  154  are inserted through the respective pivot holes  155  of the elevational adjustment component and screwed (or otherwise inserted) into the pivot holes  136  of the azimuthal adjustment component  130 . The pivot holes  136  should be slightly larger in diameter than the pivot screws  154  to allow for free elevational rotation of the elevational adjustment component  150  relative to the azimuthal adjustment component  130 . Although shown in the figures as having two pivot members (shown as screws), it should be appreciated that the elevational adjustment component may have one pivot member which goes through both of the first pivot holes  136  of the azimuthal adjustment component  130 . Also, the pivot mechanism may comprise any of a number of different fastener types, including bolts, rods, pins, bearings or the like. 
     Adjustment members  152  are inserted through adjustment holes  153  and interface with a contact plate  138  preferably having a circular profile on the azimuthal adjustment component  130  when the elevational adjustment component  150  is in a locked position. The adjustment members  152  allow for both elevational adjustment of the elevational adjustment component  150  and solid locking of the elevational adjustment component  150  into a desired location as is more fully described below. Preferably, the range of rotation for the elevational adjustment component from horizontal is at least +/−30 degrees. 
     Mounting holes  158  allow for attachment of a radio  170  or antenna  180  to the elevational adjustment component  150 . Hanging member  156  (shown as a shoulder screw) provides a hanger for loose attachment of the radio as will be described more fully below. 
     According to another embodiment of the invention, a method is disclosed for mounting the mounting assembly and radio  170  (or antenna  180 ) on a pole mount or other support structure and aligning and locking the radio/antenna into a desired azimuth and elevation position. Although the description below refers to a radio, the same steps can be performed with an antenna. In a preferred embodiment, the base  110  of the mounting assembly  100  is mounted to a support structure (shown as a pole  10  in FIG. 1) via mounting holes  120 . Subsequent to mounting the base  110  to the support structure, the radio  130  is loosely hung on the shoulder screw  156 . The head of the screw  156  can be inserted into the casting of the radio  180 , which has a slot to receive the head of the screw. The shoulder screw  156  is a convenience mechanism for an installer, allowing the installer to free up a hand for carrying screws and washers, thereby facilitating mounting of the radio  180 . Once the radio  180  is hung on the shoulder screw, the installer can tightly mount the radio  180  to the elevational adjustment component  150  via the mounting holes  159  and fasteners (not shown). 
     Once the radio  180  has been firmly mounted, a voltmeter is connected to the radio  180  to obtain power measurements, which ensure proper alignment or positioning of the azimuthal and elevational adjustment components. Once the correct power reading is obtained on the voltmeter, the adjustment components  130  and  150  can be locked into position. (The correct power reading may be either a specific power reading desired by the technician or a power reading evidencing the optimum signal.) The azimuthal and elevational adjustment components  130  and  150  are adjusted by tightening and/or loosening their respective adjustment screws. Referring to FIGS. 3-8, to solidly lock the adjustment components,  130  and  150  both adjustment screws  132  and  152  on a respective component interface with the respective contact plate  118 ,  138  on the base  110  and the azimuthal adjustment component  130 . Having a circular profile or other geometry with a center eccentrically located to the pivot axes of the adjustment components provides for a solid locking geometry. As noted above, contact plates having other profiles with focal points for contact by the adjustment screws may be used as well. To adjust the positioning of the adjustment components,  130 ,  150  one adjustment screw on each component is extended and one adjustment screw is withdrawn. By having two screws, one on each side of the adjustment component  130 ,  150 , the adjustment component cannot move without adjusting the screws. This provides a solid locking between the all three of the main components  110 ,  130 ,  150  of the mounting assembly  100 . 
     As is apparent from FIGS. 3-8, in order to vary the angle of rotation, the length of the adjustment screws, for both the azimuthal and elevational adjustment components, from the adjustment component  130 ,  150  to the respective contact plate  118 ,  138  to which the screws interface is changed. Referring to FIGS. 3-8, using geometry and trigonometry principles, screw length e can be determined as a function of the angle of rotation θ as described by the following equations: 
     Constants 
     b=length between center point of axis of rotation and screw extensions end point on rotating component. 
     c=length between center point of axis of rotation and center of circular profile of contact plate. 
     τ=radius of circular profile of contact plate. 
     φ=angle between b and e, the screw extension length. 
     A i =angle between b and c when θ (rotation angle)=0. 
     (Upper case=angles, lower case=lengths) 
     Triangle 1: 
     At θ=0, from geometry, A i  can be calculated. Then A as a function of rotation angle θ can be defined as: 
     
       
           A (θ)= A   i −θ 
       
     
     (Note: from here on, A (θ) will be referred to as A). 
     From the law of cosines, 
     
       
         
           a={square root over (b 2 +c 2 −2bc cos(A))} 
         
       
     
     Substitute for A to find a as a function of θ: 
     
       
         
           a={square root over (b 2 +c 2 −2bc cos(Ai−θ))} 
         
       
     
     Similarly, to find angle C:              C   =       sin     -   1            (       c                   sin        (   A   )         a     )                   =       sin     -   1       (       c                   sin        (     Ai   -   θ     )               b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )               )                           
     Triangle 2: 
     Angle D can be calculated as follows: 
     
       
         
           D=C−φ 
         
       
     
     Substituting for C:        D   =         sin     -   1       (       c                   sin        (     Ai   -   θ     )               b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )               )     -   φ                     
     Similarly, F can be solved:              F   =                  sin     -   1            (       a                 sin                 D     τ     )                   =                  sin     -   1       [                   b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )             ·               sin   (         sin     -   1       (       c                   sin        (     Ai   -   θ     )               b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )               )     -   φ     )           τ     ]                           
     Next, solving for E: 
     
       
           E= 180 −D−F   
       
     
     Substituting:        E   =     180   -       sin     -   1       (       c                   sin        (     Ai   -   θ     )               b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )               )     +   φ   -       sin     -   1       [                   b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )             ·               sin   (         sin     -   1       (       c                   sin        (     Ai   -   θ     )               b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )               )     -   φ     )           τ     ]                       
     And e can found using sin law        e   =       r                   sin        (   E   )           sin        (   D   )                         
     substituting for E and D gives e as a function of θ:          e   =     τ   ·     sin   [     180   -       sin     -   1       (       c                   sin        (     Ai   -   θ     )               b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )               )     +   φ   -       sin     -   1            {                   b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )             ·               sin   (         sin     -   1       (       c                   sin        (     Ai   -   θ     )               b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )               )     -   φ     )           τ     }         ]           sin        [         sin     -   1       (       c                   sin        (     Ai   -   θ     )             b   2     +     c   2     -     2      bc                   cos        (     Ai   -   θ     )             )     -   φ     ]                       
     This geometry, wherein adjustment screws on an azimuthal or elevational adjustment member interface with a contact plate having a center point which is eccentrically located from the pivot axis on which the adjustment member rotates, provides advantages including a solid locking mechanism, a relatively short lever arm for a more compact and stronger structure, and two independently adjustable pivot axes for easier and more efficient alignment. 
     While preferred embodiments of the present invention have been described, it is to be understood that the embodiments described are illustrative only and the scope of the invention is to be defined solely by the appended claims when accorded a full range of equivalents, many variations and modifications naturally occurring to those of skill in the art from a perusal thereof. For example, although the mounting assembly has been shown and described as an apparatus for mounting and adjusting a radio/antenna, the mounting assembly of the present invention may be used for mounting various equipment that may require azimuthal or elevational adjustment.