Patent Publication Number: US-6659409-B2

Title: Positioning poles for surveying equipment, global positioning antennas, and the like

Description:
FIELD OF THE INVENTION 
     The present invention relates to monopoles and survey poles for holding and positioning surveying equipment, global positioning antennas, and the like. 
     BACKGROUND OF THE INVENTION 
     There is a need in the surveying art and the global positioning (GPS) art to enable easy set-up of monopoles and surveying poles, and compact storage when not in use. There is a further need for these poles to be inexpensive to manufacture and convenient to transport. The present invention is directed to addressing these needs. 
     SUMMARY OF THE INVENTION 
     Broadly stated, the present invention encompasses a positioning pole comprising a center pole, a first guide disposed on an outer surface of the center pole, a first support leg, and a first attachment coupler which pivotally attaches the first support leg to the first guide. In preferred embodiments, the center pole has an elongated dimension and an outer surface disposed along the elongated dimension, and the first guide has an elongated dimension oriented parallel to the elongated dimension of the pole. Also in preferred embodiments, the first attachment coupler has an elongated dimension, a first face, and a second face, with the elongated dimension being shorter than the elongated dimension of the first guide. The first face of the first attachment coupler has a contoured surface which interfits with the first guide of the pole and enables the first attachment coupler to slide along the elongated dimension of the first guide without separating from the guide in directions that are perpendicular to the guide&#39;s elongated dimension. 
     Also in preferred embodiments, the positioning pole comprises one or more additional sets of guides, attachment couplers, and support legs. In addition, a locking mechanism is included to lock each attachment coupler to its corresponding guide once a desired position is found for its respective support leg. 
     To store the positioning pole, each of the support legs can be rotated toward, and positioned against, the center pole (i.e., folded against the center pole), and with each attachment coupler being slide toward the top end of the center pole to a point where the length of its respective support leg is disposed within the length of the center pole. When the positioning pole is to be put into use, the center pole is positioned over the monument or surveying mark and set in a rough plumb position, then each leg is rotated outward and the respective attachment coupler is slide down its respective guide until the bottom end of the support leg encounters a supporting location on the ground. The center pole is then placed into a fine plumb position by axially pivoting it around the monument point, during which time the attachment couplers freely move along their respective guides to accommodate the pivoting rotation while not losing their anchoring spots at the ends of the support legs. Once the fine plumb position is found, the attachment couplers may be locked into position against the center pole. The construction of the present invention enables this very simple and fast method of placing and securing the center pole in a plumb position. 
     The above-described construction enables each support leg to couple into the center pole at a plurality of points along the center pole, enables each set of attachment coupler and support leg to couple into the center pole at a different and independent location to better match the ground topology, enables each support leg to be placed at a different and independent angle with respect to the center pole to also better match the ground topology, and enables easy locking of the leg positions once the plumb point of the center pole is found. Usually the support legs in prior art tripods are constructed with adjustable lengths, and the positioning of the ends of these legs on the ground is adjusted by adjusting the length of the support legs. While adjustable-length support legs may be used in the present invention, the above-described sliding construction of the present invention provides an additional way of positioning the ends of the support legs, one which is more convenient in many ways to the telescoping mechanism of the prior art tripod poles. 
     As described in greater detail below, the above-construction of the present invention enables the center pole and support legs to be made by inexpensive extrusion methods, and enables the attachment couplers and locking arms to be made by inexpensive casting methods. 
     Accordingly, it is an object of the present invention to provide a position pole for surveying equipment, global positioning antennas, and the like which is easy and quick to place and secure into a plumb position. 
     It is a further object of the present invention to enable the components of positioning poles according to the present invention to be formed by inexpensive manufacturing methods. 
     It is yet another object of the present invention to provide a position pole which is compact to store and convenient to transport. 
    
    
     These and other objects of the present invention will become apparent to those skilled in the art from the following detailed description of the invention, the accompanying drawings, and the appended claims. 
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows an exemplary positioning pole according to the present invention. 
     FIG. 2 shows a isometric view of a section of an exemplary center pole according to the present invention. 
     FIG. 3 shows an end view of the exemplary center pole shown in FIG. 2 according to the present invention. 
     FIG. 4 shows a perspective view of an exemplary support leg according to the present invention. 
     FIG. 5 shows a perspective view of an exemplary attachment coupler according to the present invention. 
     FIG. 6 show a side view of the exemplary attachment coupler of FIG. 5 according to the present invention. 
     FIG. 7 shows an end view of the exemplary attachment coupler of FIG. 5 according to the present invention. 
     FIG. 8 shows a isometric view of a locking arm according to the present invention. 
     FIG. 9 shows an end view of the exemplary locking arm shown in FIG. 8 according to the present invention. 
     FIG. 10 shows a cross-sectional view of the interfitting surfaces of another exemplary set of a coupler and guide according to the present invention. 
     FIG. 11 shows a cross-sectional view of the interfitting surfaces of yet another exemplary set of a coupler and guide according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 shows an exemplary positioning pole  10  according to the present invention. Positioning pole  10  comprises a center pole  20 , a top mount piece  15  having a threaded shaft for receiving a global positioning system (GPS) antenna  5  or other surveying equipment  5 , a bottom marker  18 , two or more legs  50  for supporting center pole  20 , and two or more attachment couplers  60  for attaching the legs  50  to center pole  20 . Center pole  20  has an elongated dimension (e.g., a length), a diameter, an outer surface disposed along the elongated dimension, a first guide  21  disposed on the pole&#39;s outer surface having an elongated dimension oriented parallel to the elongated dimension of pole  20 , and a second guide  22  disposed on the pole&#39;s outer surface having an elongated dimension oriented parallel to the elongated dimension of pole  20 . Guides  21  and  22  provide guide tracks upon which attachment couplers  60  can slide, thereby enabling the top ends of legs  50  to be positioned at a plurality of places along the elongated dimension of center pole  20 . The position of each coupler  60  along its respective guide may be locked in by a respective locking arm  80 , as described below in greater detail. In preferred embodiments of the present invention, center pole  20  has a third guide  23  (shown in FIGS.  2  and  3 ), and the three guides  21 - 23  are spaced at equal distances around the diameter of center pole  20  (i.e., they are spaced at 120-degree angles around the center axis CA of pole  20 ). 
     FIG. 2 shows a isometric view of a section of center pole  20 , and FIG. 3 shows a cross-sectional view thereof. In preferred embodiments, center pole  20  comprises three elongated support bars  31 - 33  disposed around the pole&#39;s center axis CA and spaced apart from one another by equal angles of 120 degrees, as measured around the center axis CA. As best shown in FIG. 3, each support bar  31 - 33  preferably has a flat middle section, and two curved outer sections which bend inward toward the center axis CA by an angle of approximately 60 degrees. Center pole  20  further comprises three elongated flat bars  21 - 23  which are disposed around the pole&#39;s center axis CA and disposed between support bars  31 - 33  in an interleaved manner. Flat bars  21 - 23  are preferably spaced apart from one another by equal angles of 120 degrees, as measured around the center axis CA (i.e., at 120-degree segments of a circle which has its center disposed on the center axis, and which has its circumference and radius perpendicular to center axis CA). A plurality of elongated support ribs  24 - 29  connect the flat bars  21 - 23  to the pole&#39;s support bars. Specifically, the back surface of flat bar  21 , which is the surface facing center axis CA, is coupled to a side edge of support bar  33  by support rib  24 , and to a side edge of support bar  31  by support rib  25 . In a similar manner, the back surface of flat bar  22  is coupled to another side edge of support bar  31  by support rib  26 , and to a side edge of support bar  32  by support rib  27 . Also in a similar manner, the back surface of flat bar  23  is coupled to another side edge of support bar  32  by support rib  29 , and to another side edge of support bar  33  by support rib  28 . 
     Support ribs  24 - 29  are disposed inward from respective outer edges of flat bars  21 - 23  to form a plurality of elongated grooves  34 - 39  that are disposed between flat bars  21 - 23  and support bars  31 - 33 . The elongated dimensions of the grooves are parallel to the center axis CA of pole  20 . Grooves  34  and  35  are disposed between the back surface of flat bar  21 , the outer surfaces of support bars  31  and  33  at their side edges, and the outer surface of support ribs  24  and  25 . Flat bar  21  and grooves  34  and  35  provide a first guide (generally referred to by reference number  21 ) upon which an attachment coupler  60  can slide. In a similar manner, grooves  36  and  37  are disposed between the back surface of flat bar  22 , the outer surfaces of support bars  31  and  32  at their side edges, and the outer surface of support ribs  26  and  27 . Flat bar  22  and grooves  36  and  37  provide a second guide (generally referred to by reference number  22 ) upon which an attachment coupler  60  can slide. Finally, grooves  38  and  39  are disposed between the back surface of flat bar  23 , the outer surfaces of support bars  32  and  33  at their side edges, and the outer surface of support ribs  28  and  29 . Flat bar  23  and grooves  36  and  37  provide a third guide (generally referred to by reference number  23 ) upon which an attachment coupler  60  can slide. 
     This particular construction enables one to manufacture center pole  20  with an extrusion process in which all of the bars  21 - 23  and  31 - 33  and support ribs  34 - 39  are formed and attached together simultaneously, and with the grooves  34 - 39  formed simultaneously therewith, which leads to lower manufacturing costs. As a characteristic of the extrusion process, the outer surface of the center pole is continuous with the outer surface of each guide at the locations where the guides are attached to the center pole. 
     In preferred embodiments, center pole  20  has a length of between 1.5 meters and 2 meters, and a diameter of around 5 centimeters (legs  50  are about 1 meter in length). Table I provides some exemplary values for the dimensions shown in FIG.  3 . 
     
       
         
           
               
               
               
             
               
                   
                 TABLE I 
               
               
                   
                   
               
             
            
               
                   
                 R1 
                 2.32 centimeters 
               
               
                   
                 D1 
                 4.27 centimeters 
               
               
                   
                 D2 
                 4.94 centimeters 
               
               
                   
                 W1 
                 1.92 centimeters 
               
               
                   
                 W2 
                  9.5 millimeters 
               
               
                   
                 T1 
                  1.0 millimeter 
               
               
                   
                 T2 
                  1.5 millimeters 
               
               
                   
                   
               
            
           
         
       
     
     FIG. 4 shows a perspective view of an exemplary support leg  50  according to the present invention. Support leg  50  comprises an elongated tubular member  51  having a front curved section, a flat back section opposite to the front section, and two side sections, each side section being disposed between the front and back sections. Support leg  50  further comprises a top end  57  which couples into attachment coupler  60 , a bottom end  58  for contacting the ground, and two apertures  52  and  53  formed in respective side sections of tubular member  50  near top end  58 . A bolt  54  may be passed through apertures  52  and  53  and corresponding apertures in attachment coupler  60  to secure leg  50  to coupler  60 . This is described in further detail below. Cover insert panels (not shown) may be fitted on to ends  57  and  58  to cover them. 
     FIG. 5 shows a perspective view of an exemplary attachment coupler  60  according to the present invention, and FIGS. 6 and 7 show side and end views thereof, respectively. Coupler  60  has an elongated dimension L, a first face  61 , and a second face  62 . The elongated dimension L is shorter than the elongated dimension of the guides  21 - 23  and of center pole  20 . First face  61  has a contoured surface which interfits with a guide  21 - 23  of center pole  20  and enables the attachment coupler  60  to slide along the elongated dimension of the guide without separating from the guide in directions that are perpendicular to the guide&#39;s elongated dimension. 
     In a preferred embodiment, attachment coupler  60  comprises a first elongated angle bar  64  and a second elongated angle bar  70 . Angle bar  64  comprises an elongated dimension L, a first leg section  65  having a length disposed parallel to the elongated dimension, a second leg section  66  having a length disposed parallel to the elongated dimension, and a salient angle  67  between its first and second leg sections. (A salient angle is an angle which is less than 180 degrees in value.) Similarly, angle bar  70  comprises an elongated dimension L, a first leg section  71 , a second leg section  72 , and a salient angle  73  between its first and second leg sections. Salient angles  67  and  73  are preferably less than 135 degrees in value, are more preferably between 70 degrees and 110 degrees in value, and most preferably substantially right angles (e.g., within a few degrees of 90 degrees). Angle bars  64  and  70  are disposed such that their elongated dimensions L are at least approximately parallel to one another, such that their salient angles  67  and  73  face one another, and such that each of the second leg sections  66  and  72  may interfit with a respective groove  34 - 39  of a guide  21 - 23 . While angle bars  64  and  70  have been shown as being disposed parallel to one another, they may be disposed so that the are approximately parallel to one another (such as within 10 degrees of a parallel orientation). 
     Attachment coupler  60  further comprises a tie bar  63  which has one end attached to first leg section  65  of angle bar  64  and a second end attached to first leg section  71  of angle bar  70 . 
     A leg  50  is attached at the second face  62  of coupler  60  by bolt  54  passed through a plurality of apertures  68  and  74  of coupler  60  and apertures  52 - 53  of leg  50 . A nut  55  is secured onto the threaded end of bolt  54 . Other means of securing may be used. The construction enables leg  50  to be pivotally mounted to coupler  60  at the apertures  68  and  74 . 
     Referring to FIG. 1, positioning pole  10  further comprises a first locking arm  80  which locks the position of attachment coupler  60  to center pole  20  once a desired position for the leg which is coupled to the coupler has been found. Attachment coupler  60  comprises an aperture  69  on angle bar  64  and an opposing aperture  75  on angle bar  70 , as shown in FIG. 5, for pivotally attaching locking arm  80 . FIG. 8 shows a isometric view of locking arm  80 , and FIG. 9 shows an end view thereof. Locking arm  80  has a lever section  81  and cylindrical member section  82 . Cylindrical member section  82  has a flat top surface  83 , a flat bottom surface  84 , a curved side surface  85  which provides a cam surface, a center axis  86  passing perpendicularly through the top and bottom surfaces, a radius r extending from the center axis  86  to a plurality of points on the curved side surface. Center axis  86  is at the intersection of the large crosshairs in FIG.  9 . Cylindrical member section  82  may comprise a full cylinder, or may comprise a partial cylinder. In preferred embodiments, Cylindrical member section  82  and lever arm  81  are formed as an integral unit. Cylindrical member section  82  further comprises an aperture  88  passing perpendicularly through the top and bottom surfaces along an axis  89  which is off-center of center axis  86  (i.e., which is in a different location from the location of center axis  86 ). Cylindrical member section  82  is disposed between top surface  84  and bottom surfaces  85 , and is positioned between the angle bars  64  and  70  of coupler  60  with its aperture  88  aligned with apertures  69  and  75  of coupler  60 . A bolt  90  (shown in FIG. 8) is passed through apertures  69 ,  75 , and  88  to pivotally attach locking arm  80  to the second surface  62  of coupler  60 . A nut  91  is secured onto the threaded end of bolt  90 . Other means of securing bolt  90  may be used. 
     Cylindrical member section  82  is positioned between the angle bars  64  and  70  such that the center axis of aperture  88  is closer to the first surface  61  than the center axis  86  of cylindrical member section  82 . When lever section  81  is oriented in the vertical upright position, there is sufficient space between curved side surface  85  and the second leg sections  66  and  72  of coupler  60  to allow a flat bar  21 - 23  to slide freely between them and along the elongated direction. As the lever section  81  is rotated downward, portions of curved surface  85  are rotated into contact with the flat bar  21  (or  22  or  23 ) due to aperture  88  being off-center from axis  86 . The contact pushes flat bar  21  (or  22  or  23 ) into contact with the opposing second leg sections  66  and  72  of the angle bars  64  and  70 , respectively. Further rotation of lever arm  81  causes the flat bar to be locked against the second leg sections  66  and  72  and held by frictional forces. 
     To store positioning pole  10 , each of the support legs  50  may be rotated toward, and positioned against, center pole  20  (i.e., folded against the center pole), with each attachment coupler  60  being slide toward the top end of center pole  20  to a point where the length of each support leg  50  is disposed within the length of center pole  20 . When the positioning pole  10  is to be put into use, bottom marker  18  of center pole  20  is positioned over the monument or surveying mark and set in a rough plumb position, then each leg  50  is rotated outward and the respective attachment coupler  60  is slide down its respective guide  21 - 23  until the bottom end  58  of the support leg  50  encounters a supporting location on the ground. Center pole  20  is then placed into a fine plumb position by pivoting it around the monument point, during which time the attachment couplers  60  freely move along their respective guides  21 - 23  to accommodate the pivoting rotation while not losing their anchoring spots at the ends  58  of the support legs  50 . To facilitate this action, legs  50  may be initially rotated outward from center pole  20  at an angle which is between 75% and 90% of the maximum angle at which leg  50  can be extended. Once the fine plumb position is found, the attachment couplers  60  may be locked into position by locking arms  80 . The construction of the present invention enables this very simple and fast method of placing and securing the center pole  20  and the equipment on top in a plumb position. 
     The above-described construction enables each support leg  50  to couple into center pole  20  at a plurality of points along the center pole  20 , enables each set of attachment coupler  60  and support leg  50  to couple in at a different and independent location to better match the ground topology, enables each support leg  50  to be placed at a different an independent angle with respect to the center pole  20  to also better match the ground topology, and enables easy locking of the leg positions by simple rotation of locking arms  80  once the plumb point of the center pole  80  is found. Usually the support legs in prior art tripods are constructed with adjustable lengths, and the positioning of the ends of these legs on the ground is adjusted by adjusting the length of the support legs. While adjustable-length support legs may be used in the present invention, the above-described sliding construction of the present invention provides an additional way of positioning the ends of the support legs, one which is more convenient in many ways to the telescoping mechanism of the prior art tripod poles. 
     It may be appreciated that other interfitting surfaces between attachment coupler  60  and guide  21  may be used. FIG. 10 shows another such embodiment where a flat beam  21 ′ is coupled to a center pole  20 ′ by a single support rib  24 ′. FIG. 11 shows another embodiment where two dovetail grooves  201  and  202  are formed in a center pole  20 ″, and two corresponding interfitting dovetail  211  and  212  protrusions are formed in a attachment coupler  60 ″. 
     While the present invention has been particularly described with respect to the illustrated embodiments, it will be appreciated that various alterations, modifications and adaptations may be made based on the present disclosure, and are intended to be within the scope of the present invention. While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the present invention is not limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.