Abstract:
A telescoping tower comprises a plurality of telescoping tower sections, each tower section having a pressure member that engages with a respective pressure member on a respective tower section when the tower sections are moved from a nesting condition to an extended position, the engagement of the pressure members occurring at the overlap of the tower sections to increase stability of the telescoping tower and reduce unwanted play at the overlap regions.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a telescoping tower generally, and more particularly to an unguyed telescoping tower implementing a pressure bar system to impart stability to the tower structure. 
       BACKGROUND 
       [0002]    Telescoping towers are traditionally used in areas unsuited for permanent tower installations such as in a military arena, a news hot spot, a disaster zone where existing communication lines have been temporarily or permanently disabled, and the like. Other uses include, but are not limited to, site surveys, testing and monitoring, data collection, and wireless data transfer. Most commonly, telescoping towers are used to facilitate the establishment of mobile communications in a relatively short period of time. 
         [0003]    There are generally two known problems with mobile telescoping tower applications. First, as the height of the tower increases, the stability of both the tower and the interface or overlap between tower sections decreases. This is traditionally remedied with guy wires or the like. However, the process of installing guy wires can add an average of an hour to the installation and possibly require additional manpower, which are time and resources that are usually unavailable in an emergent or crisis situation, and which results in the second problem. 
         [0004]    These two problems are resolved through the use of unguyed towers. By eliminating the need for guy wires, the time spent on guy wire installation can be better utilized during crucial emergency instances where communication towers are vital. Furthermore, unguyed towers can be advantageous where the use of guy wires and anchors are not feasible. Specific applications where guy wire use would be obstructed include urban areas with many buildings, near bodies of water, presence of underground cables or pipes, heavily wooded areas or hard, rocky ground. 
         [0005]    There is a need, therefore, for an unguyed tower that can be erected quickly and efficiently, and that is stable at heights that traditionally require guy wire support. This need is met by the telescoping tower of the present disclosure. 
       SUMMARY 
       [0006]    A telescoping tower having a plurality of telescoping tower sections is provided with pressure bar assemblies on each tower section. When a first tower section is extended relative to a second tower section, a pressure bar assembly on one side of the first tower section engages with another pressure bar assembly on a mating side of the second tower section at the overlap between the two tower sections, with the engagement of the pressure bar assemblies causing a pressure or force to act on the other sides of the first and second tower section to close the gap and thereby reduce unwanted play between such respective tower sections. The increased pressure at the overlap results in increased stability of the telescoping tower as a whole and enables the tower to withstand environmental challenges in an unguyed condition. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is one embodiment of an erected telescoping tower in accordance with the present invention. 
           [0008]      FIG. 2  is one embodiment of a telescoping tower in a nested condition. 
           [0009]      FIG. 3A  is one embodiment of one section of a telescoping tower. 
           [0010]      FIG. 3B  is one embodiment of a portion of the section of  FIG. 3A . 
           [0011]      FIG. 4  is one embodiment of one section of a telescoping tower. 
           [0012]      FIG. 5  is one embodiment of one section of a telescoping tower. 
           [0013]      FIGS. 6A-6D  are schematic illustrations of one embodiment of the engagement of pressure bars of two tower sections. 
           [0014]      FIG. 7  is a schematic illustration of a two section tower. 
           [0015]      FIG. 8  is one embodiment of a rung implemented roller. 
           [0016]      FIG. 9  is one embodiment of a drive structure implemented in the present disclosure. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0017]    This disclosure describes the best mode or modes of practicing the invention as presently contemplated. This description is not intended to be understood in a limiting sense, but provides an example of the invention presented solely for illustrative purposes by reference to the accompanying drawings to advise one of ordinary skill in the art of the advantages and construction of the invention. In the various views of the drawings, like reference characters designate like or similar parts. 
         [0018]      FIG. 1  illustrates one embodiment of an erected telescoping tower  100  formed generally from a first section  110 , a second section  120 , and a third section  130 . A mast  140  may extend from the third section  130  for supporting an antenna or some other data collection device. Other attachments are contemplated. In the embodiments described herein, a telescoping tower  100  of triangular cross-section will be used for purposes of illustration, it being understood that other cross-sectional configurations are within the scope of the present disclosure. It will also be appreciated that while three tower sections are shown, it will be understood that a telescoping tower in accordance with the present disclosure can have as few as two sections and more than three sections if desired. The size, shape, length and cross-section configurations described herein are illustrated for purposes of example and are not intended to be limiting. However, for purposes of explanation and by way of example only, for an illustrated seventy-eight foot tower installation, each tower section would have a height of thirty feet with a six foot overlap at the transition between each tower section, resulting in the first section  110  having a visible height of thirty feet, and the second and third tower sections  120 ,  130  each having a visible height of twenty-four feet. Of course, other dimensions, overlaps, etc., are contemplated to meet specific environmental demands. 
         [0019]    As shown in  FIG. 2 , which illustrates a schematic, nested view of the tower sections  110 ,  120  and  130 , the first section  110  has the largest width  210 , the third section  130  has the smallest width  230 , and the second section  120  has a width  220  that is between the first and third widths  210 ,  230 . In certain embodiments, the first section  110  might be anchored to a base of some sort, a fixed building, a portable trailer structure or the like (all not shown). However, for purposes of this discussion, the anchoring of the telescoping tower to the ground or some other support structure will not be illustrated or described in detail, it being understood that a variety of anchoring means now known or hereinafter developed may be utilized as desired. 
         [0020]    Each of the tower sections  110 ,  120 ,  130  will now be described in more detail in  FIGS. 3A-5  as first, second and third tower sections  300 ,  400  and  500 . Each tower section generally has three sides, with first tower section  300  ( FIG. 3A ) having sides  310 ,  320 ,  330  and second tower section  400  ( FIG. 4 ) having sides  410 ,  420 ,  430  and third tower section  500  ( FIG. 5 ) having sides  510 ,  520 , and  530 . Each side has an interior that faces the other sides, and an exterior that faces away from the respective tower section. In a nested condition, when the three tower sections  300 ,  400 ,  500  are fully collapsed, the exterior of the second tower section  400  faces the first tower section  300 , and the exterior of the third tower section  500  faces the second tower section  400 . 
         [0021]    Positioned along an upper section  312  (only the upper section  312  of tower section  300  is shown in  FIG. 3A  for clarity) of the interior of side  310  of the first section  300  is preferably a pair of pressure bars  340 ,  350  supported on the side  310  by a plurality of horizontally-aligned, vertically-spaced rungs  360 .  FIG. 3B  illustrates a close up view of the pressure bar arrangement shown in  FIG. 3A  shown from the interior of the tower section  300 . While a pair of pressure bars is preferred and shown in the embodiments discussed herein for purposes of explanation, it will be appreciated that at least one and more than two pressure bars can be utilized as desired. Similarly, while the pressure bars are situated on certain illustrated sides, it will be appreciated that other sides may be used as long the relative engagement of pressure bars between tower sections is maintained as will be described in more detail. 
         [0022]    More specifically, each pressure bar  340 ,  350  is preferably formed from a static-dissipative ultra-high molecular weight (UHMW) polyethylene rectangular material with a low coefficient of friction, high impact strength and weather resistance. Of course, other types of materials are contemplated. In one example where the first tower section  300  is approximately thirty feet long, each pressure bar  340 ,  350  is preferably two inches wide, one-half inch thick and sixty inches (five feet) long, and is bolted at a plurality of locations with countersunk bolts  345  to further support bars  342 ,  352 , that are then welded or otherwise fixed to laterally extending rungs  360 , that are then welded or otherwise fixed to the longitudinally-extending side frames  314 ,  316  that form the side  310  (see  FIGS. 3A and 3B ). In the illustrated embodiment, these horizontal rungs  360  replace the traditional horizontal and diagonal rungs present along the remainder of the side  310 . 
         [0023]    Similar pressure bar assemblies are provided on the second and third tower sections  400 ,  500  as shown in  FIGS. 4 and 5 . More specifically on the second tower section  400 , pressure bars  440 ,  450  are situated on an exterior side of a lower section  414  of side  410  in a facing relationship with side  310  of the first tower section  300 , and additional pressure bars  460 ,  470  are situated on an interior side of an upper section  412  of side  410  in a facing relationship with side  510  of the third tower section  500 , with only the upper and lower sections  412 ,  414  of the tower section  400  being shown for clarity. On the third tower section  500  (only the lower section  514  of tower section  500  shown in  FIG. 5  for clarity), pressure bars  540 ,  550  are situated on an exterior side of a lower section  514  of side  510  in a facing relationship with side  410  of the second tower section  400 . 
         [0024]    Returning to  FIG. 3 , the pressure bars  340 ,  350  are positioned along the upper section  312  of the interior side  310  of the first section  300  because such region forms the overlap between the first and second tower sections  300 ,  400  when the second tower section  400  is extended relative to the first tower section  300 . The overlap region is traditionally the region of greatest concern from the perspective of the tower as a whole, since the overlap constitutes an effective joint in the tower structure, and there is typically some play that exists between tower sections at the overlap region. Excessive play at the overlap can increase the instability of the entire tower particularly during undesirable environmental conditions. It is for this reason that the pressure bars are preferably disposed at the overlap regions. Thus, with a six foot overlap between tower sections, for example, the pressure bars  340 ,  350  would preferably occupy five of the last six feet of height of the first tower section  300 , with a one foot offset preferably provided to accommodate different installation spacing. Similarly, pressure bars  440 ,  450  of the second tower section  400  would preferably occupy five of the first six feet of height of such tower section, while pressure bars  460 ,  470  would occupy five of the last six feet of height of such tower section. 
         [0025]      FIGS. 6A-6D  illustrates the engagement of pressure bar  340  of tower section  300  with pressure bar  440  of tower section  400 , it being understood that pressure bars  350  and  450  would simultaneously engage with the engagement of pressure bars  340 ,  440 . For purposes of illustration, the third tower section  500  will not be shown and only pressure bars  340 ,  440  will be shown for illustration even though pressure bars  350 ,  450  will also be described below. As shown in  FIG. 6A , when tower section  400  is extended relative to tower section  300 , the pressure bars  440 ,  450  approach pressure bars  340 ,  350  along a collision course. In order to facilitate mounting engagement of the two pressure bar assemblies, each pressure bar is provided with a tapered edge  344 ,  346 ,  354 ,  356 , (see also  FIG. 3B )  444 ,  446 ,  454 ,  456  that acts as a cam to allow the pressure bars to ramp up on each other as shown in  FIG. 6B . Once the pressure bars are in respective planar engagement ( FIG. 6C ), the pressure bars  440 ,  450  continue to advance over pressure bars  340 ,  350  with the continued extension of the second tower section  400  relative to the first tower section  300  until the pressure bar assemblies are effectively in parallel alignment and there is sufficient overlap between the first and second tower sections as shown in  FIG. 6D . As will be appreciated, the sliding engagement of the pressure bar assemblies is aided by the low coefficient of friction material and the countersunk bolts used to secure the pressure bars to the support plates. 
         [0026]    As shown in  FIG. 7 , the engagement of the pressure bar assemblies along sides  310 ,  410  forces the other two sides  420 ,  430  of the second tower section  400  against the other two sides  320 ,  330  of the first tower section  300  in order to close the gap that normally exists between the tower sections and that enables the tower sections to freely move relative to each other. This additional pressure exerted across all three sides of each tower section at the overlap between the tower sections imparts a measurable increase in stability throughout such overlap region and thereby reduces the play between the two tower sections that might otherwise be problematic in certain adverse environmental conditions. This also imparts additional stability to the entire telescoping tower structure as the two tower sections effectively function as a unified tower section, which also enables the tower section to be erected without guy wires and the like. 
         [0027]    In order to accommodate the relative movement of the tower sections while the pressure bar assemblies are engaged, given that such engagement causes the tower sections to effectively be forced together, rollers  600  ( FIGS. 3-5 ) are provided on rungs ( FIGS. 3A-5 ) at strategic locations relative to the force applied by the pressure bars so as to provide the maximum length of support. As shown in  FIG. 8 , a roller  600  is typically formed from a cylindrical collar that is situated on a rung  380  (see  FIG. 3A , for example) between a pair of stops  610 ,  620 . The roller  600  may be a single cylindrical collar or it may be formed from multiple collars placed in series. Other roller configurations are contemplated. The rollers  600  accommodate the sliding movement of the tower sections relative to each other. Without the rollers  600 , the tower sections might get damaged or be prevented from moving relative to each other as a result of the increased pressure imparted by the engagement of the pressure bar assemblies. 
         [0028]    In a preferred embodiment, all of the tower sections  300 ,  400 ,  500  are moved simultaneously via a cabled rigging disposed between the tower sections. In other words, in such an embodiment, while the second tower section  400  is erected relative to the first tower section  300 , and the pressure bar assemblies  340 ,  350  are engaged with pressure bar assemblies  440 ,  450 , the same process occurs simultaneously with respect to the erection of the third tower section  500  relative to the second tower section  400 . Thus, as the second tower section  400  is moving relative to the first tower section  300 , the third tower section  500  is moving relative to the second tower section  400 , which, in such embodiment, allows the tower assembly to be erected rather quickly. During extension of the third tower section  500  relative to the second tower section  400 , the pressure bars  540 ,  550  approach pressure bars  460 ,  470  and initiate engagement with the assistance of cam surfaces. Once the pressure bars are in respective planar engagement, the pressure bars  540 ,  550  continue to advance over pressure bars  460 ,  470  with the continued extension of the third tower section  500  relative to the second tower section  400  until the pressure bar assemblies are effectively in parallel alignment and there is sufficient overlap between the second and third tower sections. When the second and third tower sections are fully extended and the pressure bar assemblies are fully engaged at the overlap regions of the tower sections, the entire tower functions as a single unit with increased overall stability. While simultaneous movement of the tower sections is preferred, non-simultaneous movement may be contemplated if desired. 
         [0029]    In order for the pressure bar assemblies to impart sufficient force on the tower sections to increase the structural integrity at the overlap sections and for the tower as a whole, the pressure is preferably great enough such that the tower will not collapse under the force of gravity alone. In other words, in the described embodiment, the tower sections will preferably need to be pulled apart when it is desired to return the tower to its fully nested condition for storage or transport or the like. 
         [0030]      FIG. 9  illustrates one embodiment of a drive structure  700  that may be attached to the first tower section  300  to aid in the separation of the tower sections. While  FIG. 9  illustrates the attachment of the drive  700  to the first tower section  300 , it will be appreciated that other attachment scenarios are possible, that are either connected to a tower section or anchored to something apart from the tower such as a nearby building, support trailer or the like. More specifically, in this embodiment, drive structure  700  is a winch that simultaneously uses two separate cables  710 ,  720 , each moving in the opposite direction, on a single grooved drum  730 . In other words, when cable  710  is being fed from the drum  730 , the other cable  720  is being fed onto the drum  730 , and vice versa, which enables the winch to move the tower sections relative to each other, either during erection or disassembly of the tower. While a single-drum winch is preferred, it will be appreciated that other drive structures are contemplated. In addition, the drum  730  is preferably grooved to insure that the cables track correctly. A series of pulleys  740  (only one being shown for purposes of example) are strategically positioned throughout the tower sections to accommodate the cables  710 ,  720  and create the appropriate rigging necessary to quickly and efficiently, and preferably simultaneously, raise and lower a telescoping tower assembly. More specifically, in a preferred arrangement, each respective cable  710 ,  720  is associated, through a rigging assembly, with a respective tower section, for purposes of erecting one tower section relative to its adjacent tower section by pulling such respective tower sections relative to each other, and similarly, for pulling such tower sections apart when it is desired to disassemble the tower sections into their nested condition. 
         [0031]    While the present invention has been described at some length and with some particularity with respect to the several described embodiments, it is not intended that it should be limited to any such particulars or embodiments or any particular embodiment, but it is to be construed with references to the appended claims so as to provide the broadest possible interpretation of such claims in view of the prior art and, therefore, to effectively encompass the intended scope of the invention. Furthermore, the foregoing describes the invention in terms of embodiments foreseen by the inventor for which an enabling description was available, notwithstanding that insubstantial modifications of the invention, not presently foreseen, may nonetheless represent equivalents thereto.