Patent Document

BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to poles, and in particular, to poles used to elevate items to substantial heights, for example greater than 35 feet. 
     2. Problems in the Art 
     Many trade-offs exist with respect to the design of poles to elevate items to substantial heights. Examples are strength versus weight; size versus wind load; weight/size versus transportability, handling, and installation ease; and materials versus costs. 
     Wood poles have substantial strength and are relatively inexpensive. However, they are relatively high in weight and relatively difficult to transport and handle. Likewise, concrete poles have relatively high strength but are also of high weight and are cumbersome to transport and handle. 
     Additionally, there are other factors, which affect the choice of poles. Examples are the type of item to be elevated; and its size, weight, and function. Another factor is the environment. Will the pole be erected outside or inside? If erected outside, will it experience high humidity or moisture? Will it experience significant winds? Another factor is the purpose of the pole. Is it permanent or temporary? 
     Tubular steel is a popular choice for such poles. It is relatively high strength and low weight. Through galvanization, it resists rust and corrosion and therefore can be made to be durable for even outside use. Although more costly than wood, for example, its other advantages make it an attractive choice. 
     Poles greater than 35′ in height, even if made of tubular steel, will still present difficulties. Transportation issues exist. Some poles need to be on the order of 100′ or more tall. Even semi-trailer trucks may not be able to transport such lengths, at least without special and costly permits. Although tubular steel is relatively lightweight, any item of such length is cumbersome to handle. 
     Additionally, once erected, it is not trivial to conduct maintenance on an item elevated by the pole. A worker many times must be elevated to the top of the pole, which requires costly and complicated equipment. 
     Attempts have been made to address some of these problems. Poles made and assembled in sections have been tried. Transportation and handling might be easier, but assembly requires some type of relatively complex and time consuming joint between sections. 
     Another attempt, commonly owned by the owner of the present application, utilizes a tapered tubular steel pole made of sections that slip fit over one another. See, for example, U.S. Pat. No. 5,398,478, incorporated by reference herein. While such a pole has been found to be very effective for certain uses, once installed, it is difficult to disassemble, modify, or move. It therefore has limited flexibility with regard to function. 
     It is therefore a principal object of the present invention to provide a method and apparatus, which solves or overcomes the problems and deficiencies in the art. 
     Other features, objects and advantages of the present invention include a method and apparatus for a pole which is: 
     a. Collapsible, being retractable and extendible. 
     b. More easily transportable, being smaller in length and compact when in a collapsed position relative to its extended position. 
     c. Easier to handle and manipulate and install. 
     d. Extendible to a lockable position. 
     e. Unlockable to allow retraction. 
     f. Retains the benefits of tubular steel. 
     g. Quicker and easier to install and reinstall. 
     h. Durable. 
     i. Economical. 
     j. Flexible regarding uses and functions. 
     These and other objects, features and advantages of the invention will become more apparent with reference to the accompanying specification and claims. 
     SUMMARY OF THE INVENTION 
     The present invention includes an elongated pole extendible to substantial heights. A lower end is adapted for mounting to a support. At least first and second pole sections are adapted to move relative to one another so that one nests inside the other in a collapsed or retracted position. The first and second pole sections can telescopically extend from the retracted position to an extended position. A releasable locking member or members can selectably lock the first and second pole sections into the extended position. 
     A further feature of the invention includes adding additional pole sections having the same attributes. Multiple pole sections can be collapsed so that all pole sections nest in a first pole section but can be telescopically extended. Releasable locking member(s) can be placed to lock each adjacent pair of pole sections. The method according to the invention includes elevating an item by telescopically extending one or more sections of a pole and locking the extended sections in position. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front elevational partial sectional view of a collapsible pole, according to preferred embodiment of the present invention, shown in a collapsed position on a base. 
     FIG. 2 is similar to FIG. 1 but is a reduced in size version showing pole of FIG. 1 in a fully extended position. 
     FIG. 3 is a top plan view of FIG.  1 . 
     FIG. 4 is a reduced in scale perspective view of an example of a portable base with the pole of FIG. 1, and shows cross arms at the top of the extended pole. 
     FIG. 5 is enlarged isolated perspective view of a preferred embodiment of a bottom-most pole section of the pole in FIG. 1 with a succeeding pole section in extended position and a pole rotation tool shown in ghost lines. 
     FIG. 6 is a side elevational and partial interior cut away view of FIG.  5 . 
     FIG. 7 is an enlarged bottom plan view of FIG.  6 . 
     FIG. 8 is an enlarged top plan view of FIG. 6 also showing a catch pin and succeeding pole section in place. 
     FIG. 9 is an isolated side elevational view of the top of FIG.  6 . 
     FIG. 10 is an enlarged partial sectional view of the bottom portion of FIG.  2 . 
     FIG. 11 is still a further enlarged view of the region shown by dashed line  11  in FIG.  10 . 
     FIG. 12 is an enlarged view of the region shown by dashed line  12  in FIG.  1 . 
     FIG. 13 is an enlarged view of the region shown by dashed line  13  in FIG.  1 . 
     FIG. 14A is an enlarged view of the top part in FIG.  5 . 
     FIG. 14B is an enlarged view of the top of a collapsible pole section showing grasping ears that can be used to grab the section to extend it or retract it. 
     FIG. 15 is a bottom plan view of the bottom of pole section that telescopically nests within the base pole section in FIG.  6 . 
     FIG. 16 is a side elevational view of FIG.  15 . 
     FIGS. 17A and B are side and front elevational views of a locking pin shown in FIGS. 15 and 16 with FIG. 17A showing the pin in retracted and extended positions. 
     FIG. 18 is a plan view of top of pole section. 
     FIG. 19 is a top plan view of FIG. 1, showing a plurality of pole sections in a nested relationship. 
     FIG. 20 is an enlarged perspective view of a locking or catch pin of FIG.  17  and its mounting block and spring. 
     FIG. 21 is a side elevational view of the pin of FIG.  20 . 
     FIG. 21B is an enlarged side elevational sectional view of an alternative embodiment for a catch pin. 
     FIG. 21C is similar to FIG. 21B but shows the catch pin in a different state. 
     FIG. 22 is a top plan view of a latch catch for the catch pin of FIG.  4 . 
     FIG. 23 is a front elevational view of FIG.  22 . 
     FIG. 24A is an enlarged perspective view of two pole sections in an extended and locked position. 
     FIG. 24B is an isolated elevational view of the latch pin and latch catch of FIG.  24 A. 
     FIG. 24C is a top view of FIG.  24 A. 
     FIG. 24D is a section view taken along line  24 D- 24 D of FIG.  24 C. 
     FIGS. 25A-D are similar to FIGS. 24A-D except that the two pole sections are moved slightly relative to one another along the longitudinal axis. 
     FIGS. 26A-26D are similar to FIGS. 25A-25D except that the two pole sections are rotated slightly relative to one another. 
     FIGS. 27A-27D are similar to FIGS. 26A-26D except that the two pole sections are rotated slightly more relative to one another. 
     FIGS. 28A-28D are similar to FIGS. 27A-D but show two pole sections being slightly telescopically retracted relative to one another. 
     FIGS. 29A-29C are similar to FIGS. 28A-28D but show two pole sections completely retracted relative to one another. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     To achieve a better understanding of the invention, one embodiment thereof will now be described in detail. Frequent reference will be taken to the drawings. Reference numbers and letters will be used in the drawings to indicate certain parts and locations in the drawings. The same reference numbers or letters will be used throughout the drawings to indicate the same parts and locations, unless otherwise indicated. 
     General Environment 
     This detailed description will discuss an embodiment of a pole that can be used for both permanent and temporary purposes. The pole will be constructed out of a plurality of telescopically moveable sections relative to a base pole section. 
     General Structure 
     FIG. 1 illustrates collapsible pole  10  according to the invention in a collapsed or retracted position on base  12 . What will be called a base pole section  14  is mounted on base  12 . Pole sections  16 ,  18  and  20  nest within base pole section  14  but have upper ends which extend outside of their immediately preceding pole section. A pole top  22  is mounted at the top of pole section  20 . Pole top  22  does not move relative to pole section  20 . 
     FIG. 1 is a sectional view and illustrates the nesting of sections  16 ,  18 , and  20  within section  14 . In comparison, FIG. 2 shows pole  10  in fully extended position. Pole sections  16 ,  18 , and  20  are telescopically extended. As can be seen, in an extended position pole  10  appears to be a unitary tapered pole from top to bottom, as opposed to a sectional pole. Also, as can be seen comparing FIGS. 1 and 2, the fully extended height of pole  10  is well over twice that of pole  10  in collapsed or retracted form (FIG.  1 ). 
     FIG. 3 is a top plan view of FIG. 1 showing pole  10  on a moveable base  12 . By further reference to FIG. 4, it can be seen that base  12  can be a portable framework  26  including an upwardly extending tapered stub  24  mounted in the framework  26 . Base pole section  14  can be removably slip-fit over stub  24  to mount pole  10  in place. Outriggers  28  can be used to provide a relatively large footprint to resist over-turning moment. A substantial amount of weight and/or equipment can be placed in the interior frame  26  to further support pole  10  or to provide such things as electrical power or components, for example, for operation of lights that could be mounted on cross-arms  30  could be attached to pole top  22 . For more specifics regarding base  12  of this type, reference can be taken to co-owned, co-pending U.S. Ser. No. 09/217,975, which is incorporated by reference herein. An example of a pole top  22  can be seen at co-owned U.S. Pat. No. 5,600,537 which is incorporated by reference. It is to be understood, however, that base  12  could also be a permanent base. Stub  24  could be permanently and rigidly mounted in the ground or in some other supporting structure. For examples of such base, reference can be taken to co-owned issued U.S. Pat. No. 5,398,478, which is incorporated by reference herein. 
     Pole  10  is made of tubular steel (0.120-0.179″ thick). Pole  10  may or may not be galvanized and may be made of different material (e.g. aluminum, Fiberglas, carbon epoxy, etc.) Each pole section  14 ,  16 ,  18 , and  20  is tapered at the following rate—0.14″ per longitudinal foot, with the very bottom of base pole section  14  having a 13.40″ diameter and the very top of pole section  20  having a 4.76″ diameter. As shown in FIGS. 1 and 2, this allows pole sections to nest within one another (FIG. 1) with substantial room between each section when nested. However, when extended, pole  10  looks like it is a unitary tapered pole from top to bottom. Most of the room between sidewalls of each of the adjacent pole sections is reduced as they are extended. 
     Table 1 below sets forth dimensions of pole  10 . 
     
       
         
               
               
               
               
               
             
           
               
                   
                   
               
               
                   
                   
                   
                 Bottom-Most 
                 Top-Most 
               
               
                   
                 Section 
                 Length 
                 Diameter 
                 Diameter 
               
               
                   
                   
               
             
             
               
                   
                 14 
                 196″ 
                 13.40″ 
                 10.93″ 
               
               
                   
                 16 
                 168″ 
                 11.15″ 
                 8.72″ 
               
               
                   
                 18 
                 168″ 
                 8.97″ 
                 6.95″ 
               
               
                   
                 20 
                 156.75″ 
                 6.76″ 
                 4.76″ 
               
               
                   
                 22 
                 66.25″ 
                 5.14″ 
                 5.00″ 
               
               
                   
                   
               
             
          
         
       
     
     As a general rule, in the fully extended position of FIG. 2, the overlap between adjacent pole sections should be 1½ diameters minimum. Retracted pole  10  is less than 25′ long. Extended, it is on the order of 60′ tall. Of course, a variety of sizes are possible. 
     As will be discussed further, releasable locks mounted on pole  10  lock adjacent pole sections in place in extended position. This additional structure is added to the pole and pole sections, but is relatively minimal in nature and weight, is non-complex, and is durable. Therefore, pole  10  obtains essentially the characteristics of a hollow tapered steel pole, but is sectional in nature, can be collapsed, and therefore can be more easily transported and handled in a collapsed state as opposed to a single piece pole of size of FIG.  2 . Stress remains relatively constant from top to bottom of pole  10  when extended. Wind drag is smallest at the top because of the tapering of pole  10 . 
     Furthermore, pole  10  can be removed from base  12  and thus stored, shipped and handled separately from base  12  until it needs to erected. 
     There is no need for extremely accurate tolerances between pole sections. Therefore, conventional commercially available tubular steel sections are readily available and are more economical because no exact tolerances are needed. 
     Specific Structure 
     FIGS. 5-23 show specific structure of pole  10 . FIG. 5 illustrates base pole section  14 . Its upper end  32  including a locking mechanism (indicated generally at  34 ). Locking mechanism  34  releasably locks pole section  14  and pole section  16  (shown in ghost lines) in extended position relative to one another. 
     Locking mechanism  34  consists of three latch catches or plates  36  fixed (e.g. 120 degrees apart) on a annular ring  38  welded to the top  32  of base pole section  14  at equally spaced apart positions. Each latch catch  36  is essentially curved to follow the curvature of the upper end  32  of base pole section  14  and includes generally a rectangular opening  40 . 
     Locking mechanism  34  also includes spring-loaded catch pins  42  mounted in catch pin blocks  44  which are in turn mounted by screws or bolts to the interior of the lower end of pole section  16 . Catch pins  42  extend through openings in the lower end of pole section  16  and are mounted to correspond in position with latch catches  36  on base pole section  14 . 
     In the position of FIG. 5, with pole section  16  fully extended and catch pins  42  aligned with openings  40  of latch catches  36 , each catch pin  42  is biased outwardly by a flat spring attached to the back of catch block  44  so that they extend radially outwardly of the diameter of the top  32  of base pole section  14 , catch pins  42  thus prevent longitudinal movement of pole section  16  relative to base section  14 , to lock the two pole sections in an extended position. 
     As will be described in more detail later, catch pins  42  can be retracted to releasably disengage locking mechanism  34  and allow pole section  16  to move longitudinally downward and collapse or retract into base pole section  14 . Catch pins  42  are retracted radially inward of the inside diameter of the top  32  of base pole section  14  to allow such movement. 
     FIG. 5 also shows base pole rotation ring  48 , welded to the lower end of base pole section  14  and having an annular opening approximately the size of the bottom opening of base pole section  14  (not shown), and base pole turning gussets  50 . This arrangement allows a tool (manual or mechanized) to be inserted therein (e.g. an elongated metal pole or rod  49 , see FIG. 5) to grab or connect to the bottom of base pole section  14  to allow it to be rotated. Such rotation is either used when seating pole  10  on stub  24  of base  12 , or when turning base pole section  14  to lock or unlock pole sections of pole  10  as will be discussed later. A washer (e.g. plastic) or other friction-reducing member could be placed between section  14  and base stub  24 . 
     FIGS. 6-11 show additional details of base pole section  14  and locking mechanism  34 . Additionally, as shown at FIGS. 6,  10 , and  11 , interior centering ramps  52  can be screwed, bolted, or welded to the interior of base pole section  14 , near its bottom. Each centering ramp  52 , with a ramp portion  54 , a middle section  56 , and a bottom section  58 , abuts a constriction  60  (see particularly FIG.  11 ). Constriction  60  is comprised of a solid annular reinforcing ring  62  welded to the interior of section  14 , with adjacent opposite sloped rings  64  and  66 . Ring  62  forces the pole section to be round. Centering ramps  52  serve to center and retain the lower end of pole section  16  when retracted to its lower most position, as shown in FIG.  1 . Constriction  60 , with sloped rings  64  and  66 , allows pins  42  of another pole section to cam action over ring  62  during extension or retraction of that pole section. 
     The tapering of pole  10  results in the gap between base pole section  14  and pole section  16  to increase the farther pole section  16  is collapsed or retracted into section  14 . Thus, centering ramps  52  are particularly valuable to retain pole sections when collapsed and deter damage, rattling, or forces that might cause any pole section to go out of round, including during shipment and handling. 
     As shown in FIG. 11, a stop block  68  can be welded or otherwise secured to middle portions  56  of centering ramps  52 . Stop blocks  68  would function as a lower limit or stop to limit how far down into base pole section  14 , pole section  16  can collapse or retract. 
     As shown in FIG. 10, the position of restriction  60  and centering ramps  52  would be high enough in base pole section  14  that they would not interfere with stub  24  of base  12  when base pole section  14  is fully seated and installed on stub  24 . 
     FIG. 12 illustrates that a similar arrangement can be used for succeeding pole sections in pole  10 . Centering ramps  52 B with lower limit/stop  68 B can be attached to the lower interior end of pole section  16 . When pole section  18  is collapsed into pole section  16 , centering ramps  52 B center pole section  18  and lower limit/stop  68 B defines how far it can be retracted relative to pole section  16 . 
     The same structure can be built into the lower interior end of pole section  18  (see centering ramps  52 C and lower limit/stop  68 C) relative to pole section  20 . FIG. 12 thus shows how pole  10 , when in collapsed or nested form, results in centering and support of the lower end of succeeding pole sections in a preceding pole section. Also, if desired, centering ramps  53  (like ramps  52 ) could be attached at spaced apart positions around the tops of the pole sections (other than the bottommost pole section) to help center the tops when collapsed (see FIG. 13 for examples). Still further if desired, a small ear or piece could be affixed to an adjacent pole section and in between ramps  52  (or  53 ) to limit rotation of one of the sections relative to the other (e.g. limit rotation to approximately 120 degrees because the ear would come into abutment with a ramp  52  (or  53 ) if it were attempted to rotate a pole section outside the angular range between ramps  52  (or  53 ); in this embodiment 120 degrees. 
     As can be easily understood, these structural relationships, in combination with the lengths of the pole sections, can be designed so that when in the fully collapsed position of FIG. 1, the upper-most ends of each of pole sections  16 ,  18 , and  20  extend outside of their immediately preceding pole section so that even in collapsed form, some portion of each pole section is available and accessible from the exterior of pole  10 . This allows each pole section to be individually grasped from the exterior for extension purposes, as will be discussed in more detail later. 
     FIG. 13 shows this relationship of the top ends of the pole sections. Note that annular ring  38  at the top of base pole section  14  is spaced a distance  70  from the very upper edge of base pole section  14 . Similarly, annular rings  38 B and  38 C, associated with locking mechanisms  34 B and  34 C of pole sections  16  and  18 , are spaced distances  72  and  74  respectively from the very tops of pole sections  16  and  18  respectively. 
     As shown in FIGS. 14-18, this arrangement allows catch pins  42  to abut and sit upon the top edge of a preceding pole section so that catch pins  42  are supported by the preceding pole section instead of annular plate  38 . 
     FIGS. 20 and 21 show catch pin  42  and catch blocks  44  in more detail. Catch block  44  has an opening  76  approximately at its center. Catch pin  42  matingly fits through opening  76  and includes a flange  78  that prevents pin  42  from moving all the way through opening  76 . A guide rib  80  on the perimeter of catch pin  42  rides within notch  82  in opening  76  to prevent catch pin  42  from rotating in opening  76 . A flat steel spring  86  is mounted in a channel  88  in the back of block  44  and holds catch pin  42  in the position shown in FIG. 20 (biases it outwardly from the front of block  44 ). A transverse cut-out or notch  84  exists in the catch pin  42 , opposite guide rib  80 . Transverse cut-out  84  is sized so that it can fit over the upper edge of the top of a pole section to further secure adjacent pole sections together when locked in extended positions. Note that the upper edge of pole section  14  can have curved cut-outs  92  (see e.g. FIG. 24B) to further secure catch pins  42  and retain pins  42  from lateral movement. 
     Spring  86  is held in position relative to block  44  by bolts or screws  85  extending through oblong apertures  90  near opposite ends of spring  86  and into threaded apertures  87  in block  44 . Block  44  is approximately 6″ long and 2″ wide by ½″ thick. 
     Pin  42  (e.g. A500 steel) is 1.485″ outside diameter. Flange  78  is 1.985″ outside diameter. Pin  42  is 1.5″ in total length, including flange  78 ; without flange  78 , pin  42  is 1.31″ long. Slot  84  is 0.38″ in width and spaced 0.53″ away from flange  78 . 
     Spring  86  is 7.63″ long, 1.88″ wide, and 0.015″ thick. It is made of 0.015″ spring steel. Pin  42  is made of A500 steel, as is block  44 . 
     FIGS. 22 and 23 depict more specifically latch catches  36 . Latch catch  36  is made of A500 steel. It is approximately 7″ long and curved along a radius of 5.58″. It is 3.75″ in width and 0.75″ thick. As shown in FIGS. 22 and 23, opening  40  is 3″ tall and has upper corners radiused at 0.75″. One side of opening  40  (see reference numeral  91 ) is 1.51″ inward from the one end of latch catch  36  and is essentially radially aligned relative to the center of curvature of latch catch  36 . The other side  94  of opening  40  is 3″ away from side  91 , but is angled approximately 45° from the radial centerline of latch catch  36 . Note also that the very end  98  of one side of latch catch  36  is sloped at 42° from the radial line shown in FIG.  22 . 
     The purpose of such structure will become more apparent with reference to the operation of the locking mechanism  34  as will be described later. 
     Operation 
     FIGS. 24-29 illustrate operation of pole  10 . FIG. 24A illustrates base pole section  14  and pole section  16  in an extended and locked position such as shown in FIG.  2 . Catch pins  42  aligned with openings  40  in latch catches  36  and transverse cut-outs  84  in catch pins  42  are seated on the upper lip  92  of base pole section  14  (see in particular  24 B and  24 D). 
     In this position, longitudinal movement of pole section  16  relative to base pole section  14  is deterred because of the weight of pole section  16  (and other pole sections), pole top  22  and any items supported by pole top  22 . Flat springs  46  of catch blocks  44  bias catch pins  42  radially outwardly. Even a force that would tend to move pole section  16  upward, would result in catch pins  42  hitting against the top of openings  40  and preventing further upward movement. 
     To collapse pole section  16  relative to base pole section  14 , force is applied upwardly on pole section  16  to lift pole section  16  and thus catch pins  42  (and particularly transverse cut-outs  84  of catch pins  42 ) off of the top edge  92  of base pole section  14  (see FIGS.  25 A-D). 
     Either base pole section  14  or pole section  16  is then rotated to move catch pins  42  in the direction of the arrows in FIGS. 26A-D. By particularly looking at FIGS. 26A and 26C, the beveled heads of catch pins  42 , in combination with ramps  94  of openings  40 , forces catch pins  42  by essentially a camming action to begin retracting. 
     This allows continued relative rotational movement of base pole section  14  and pole section  16  (see arrows in FIGS. 27A-D) until catch pins  42  are camped or retracted sufficiently to be out of openings  40  and sufficiently retracted so that transverse cut-outs  84  in catch pins  42  would not catch the top of base pole section  14 . Catch pins  42  are forced inwardly against springs  86 . 
     FIGS. 28A-D then illustrate that pole section  16  can be forced straight downwardly and catch pins  42  would not prohibit downward longitudinal movement of pole section  16  because they are moved sufficiently inwardly. Pole section  16  can then be retracted or collapsed into base pole section  14  to a position illustrated at FIGS. 29A-C, where it is noted that catch pins  42  ride along the interior surface of base pole section  14 . Pole section  16  would be collapsed to the position shown in FIGS. 1 and 12 until the bottom of pole section  16  strikes the lower limit/stop  68 . 
     The preceding has described how pole section  16  can be unlocked and retracted into base pole section  14 . The same steps would be used to unlock and retract pole section  18  relative to pole section  16  and pole section  20  relative to pole section  18 . 
     The reverse procedure would be practiced to extend pole  10  from the retracted, collapsed state of FIG. 1 to the fully extended state of FIG.  2 . 
     It is generally preferred to extend the upper-most pole section  20  first, followed by the second-to-upper-most pole section  18 , followed by the third-to-upper-most pole section  16 . One way to do so would be to use mechanical means (e.g. a lift truck or other mechanism(s) to grasp structure (for example, ears  100  (with holes  102 ) on opposite sides of the top of a pole section—see FIG.  14 B), and raise that pole section until catch pins  42  are in any of the positions of FIGS. 27A-D,  26 A-D, or  25 A-D. Ultimately, one would rotate the pole sections at issue to get catch pins  42  in the position shown in FIGS.  25 A-D—where catch pins  42  are aligned with openings  40  in latch catches  36 , but are near the top of openings  40 . Once so aligned, the upper pole section can be lowered such that transverse cut-outs  84  in catch pins  42  would seat upon the upper edge of the lower of the two pole sections (FIGS.  24 A-D). 
     The next lowest pole section could then be grasped by the mechanism and raised and locked in a similar manner. This procedure would then continue until pole  10  is fully extended. 
     The structure and the amount of work needed to extend and lock pole sections in this manner is relatively minimal and can be accomplished with mechanisms such as lift or lull trucks instead of more costly and cumbersome cranes or other similar equipment. Alternatively, a dedicated mechanical device or devices, or a self contained extension device mounted directly on the pole, could be used to slide pole sections from retracted to extended positions or vice versa. The installer could use bar or pole  49  (FIG. 5) to rotate section  14  while the device holds the extended section form rotation, so that the catch latches move to capture the catch pins and thus lock the extend section in extended position. Other methods are possible. The lift mechanism(s) can be moved from pole to pole. The pole sections can include markings to help with rotational and longitudinal alignment. For example, as roughly illustrated in FIG. 24A, a vertical line  104 A could be marked on pole section  16  and a vertical line  104 B on pole section  14 . Marks  104 A and  104 B could be placed so that when aligned with one another, pins  42  would be aligned with openings  40  in latch catches  36 . This would assist the installer, who normally is at or near the bottom of section  14 , to know when alignment is reached. Similarly, horizontal indicia or lines  106  could be marked on section  16  to help an installer visually see how close to fully extended a pole section is. The foregoing is not the only way of extending and retracting pole  10 , but is a very efficient way of doing so. 
     As has been described, this arrangement also does not require extremely close tolerances as the locking mechanisms  34  have built-in play or tolerance that allows quick and easy operation. 
     Options and Alternatives 
     It is to be understood that the aforementioned embodiment is but one form the invention can take. Alternatives, such as are within the skill of those of ordinary skill in the art, defined solely by the claims appended hereto. 
     For example, the invention is intended primarily for use with poles elevating items to substantial heights. By substantial heights, it is meant on the order of 35′ or more. As a practical matter, the range could be up to on the order of 120′ fully extended. 
     The precise dimensions of the pole sections and the locking mechanisms are to be designed for the particular height of pole, working conditions and items to be elevated. Base  12  can be either permanent or portable. Base pole section  14 , for example, could use some other type of mechanism or structure for attachment to a base. Examples would be bolts, direct burial in the ground, or other connections. Pole  10  can be used to elevate a variety of items or devices. One example given is lighting fixtures such as wide-area, high intensity lighting fixtures of the nature disclosed in U.S. Pat. No. 5,398,478. Other items are possible, including, but not limited to electrical wires, communications devices or antenna, communication wires, beacons or warning lights. 
     Note that the invention has many advantages. One example is that it allows non-remote aiming of light fixtures with less costly equipment than large cranes or the like. Another example relates to permanent lighting. The collapsible pole allows for easy lamp replacement. 
     In the preferred embodiment, the pole sections are tapered with succeeding sections generally smaller in diameter than preceding sections. It should be noted however that in the preferred embodiment, the smallest diameter of each preceding section is smaller than the largest diameter of its succeeding section. The sections are made to leave some clearance when extended relative to one another to allow for rotation between the sections. 
     However, it is possible to use the concepts discussed herein where the tapering of sections is in the opposite direction. Still further, a middle pole section could have the largest diameter, and preceding and succeeding sections smaller diameters, so that they retract into the middle member. The sections do not necessarily have to be tapered, but it is preferred. 
     FIGS. 21B and C illustrate an alternative embodiment for a catch pin. As shown in FIGS. 21B and C, alternative embodiment catch pin  42 B includes what will be called a flag  43  pivotally mounted interiorly of the front end of pin  42 B. FIG. 21B shows flag  43  in its normal state. Internal spring and ball combination  45  pushes downwardly on the short leg  43 B of flag  43  to keep it normally in the position of FIG.  21 B. However, when pin  42 B extends through opening  40 , and latch catch  36  and transverse cutout  84  of pin  42 B engages the top of a pole section, that top edge of the pole section then enters transverse cutout  84  of pin  42 B, abuts short arm  43 B of flag  43  and overcomes the downward force of spring and ball  45  to pivot flag  43  to the position shown in FIG.  21 C. In that position long arm  43 A of flag  43  would pivot out of retraction in catch pin  42 B. This would provide a visual indication to workers that pin  42 B is appropriately seated on the top of a pole section to assist the operators to confirm the extended pole sections are locked. Flag  43  could be metal or other material. It could be painted or otherwise marked to make it highly visually perceptible, even from substantial distances. 
     Previously stop blocks  68  were discussed in association with limiting the travel of nested pole sections within one another. Alternatively, stop blocks could be positioned on the outside around the top of each pole section, instead of on the inside bottom. Such alternative stop blocks would function the same way. They would limit how far down each pole section would move into the preceding pole section by extending the diameter of, and perhaps slightly outside the diameter of, the preceding pole section. Additionally, they could be spaced apart around the top of a pole section in a manner that would not allow more than a certain rotation of the succeeding pole section. For example, some type of extension or feature of the succeeding pole section could extend outwardly and limit rotation of succeeding pole section relative to the preceding pole section to the extent of spacing of stop blocks.

Technology Category: 0