Abstract:
This invention discloses a mobile tower system in which a telescoping tower may be with a plurality of tower structures may be extended to a height much greater than its contracted length. The tower may be transported horizontal, rotated to a vertical position and then the individual tower structures extended and secured via spring pins relative to the adjacent tower structure, the erection of the tower sections may be with external equipment such as a boom truck, or utilizing an internal hydraulic cylinder.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application does not claim priority from any other application. 
       TECHNICAL FIELD 
       [0002]    This invention relates to a mobile tower system for providing an expandable tower which can be moved from one location to another, and has applications, among others, for cell phone towers and antennas. 
       BACKGROUND OF THE INVENTION 
       [0003]    The proliferation of the usage of cell phones around the world has created a strong demand for additional cell phone coverage and hence additional towers carrying cell phone antennas. In some cases the demand requires a temporary cell phone tower before permanent can be installed, and others there may only be a temporary need for the cell phone tower. In some cases the temporary tower system may be used on a more permanent basis. 
         [0004]    For many reasons the cell phone towers need to be placed in locations which are not readily accessible for equipment and it is desirable to have a mobile system in which the tower can be driven directly to the location where it&#39;s to be installed and cranes or other heavy equipment are not necessary to get the tower to the specific location. In some circles the mobile tower systems are referred to as COWS, which stands for cells on wheels. 
         [0005]    It is also desirable to provide towers which will need to exceed the maximum reasonable length that can be pulled behind a vehicle and therefore would also be an advantage for such a tower to be expandable and contractible so that it can more readily fit over a reasonably sized trailer, making it more mobile and also within the normal legal load and length requirements provided by traffic laws. 
         [0006]    It is there an objective of aspects of this invention to provide a mobile tower system which may be expanded when placed at the desired tower location. 
         [0007]    It is another objective of aspects of this invention to provide a tower system in which costly equipment such as cranes are not required to install it in an expanded state at a tower location. 
         [0008]    It is a still further objective of some embodiments of this invention to provide such a tower system wherein biased spring pins may be mounted on tower structures and automatically insert into spring pin apertures on adjacent tower structures to secure adjacent tower structures with respect to one another and prevent relative movement therebetween. 
         [0009]    While the invention was motivated in addressing some objectives, it is in no way so limited. The invention is only limited by the accompanying claims as literally worded, without interpretive or other limiting references to the specification, and in accordance with the doctrine of equivalents. 
         [0010]    Other objects, features and advantages of this invention will appear from the specification, claims, and accompanying drawings which form a part hereof. In carrying out the objects of this invention, it is to be understood that it&#39;s essential features are susceptible to change in design and structural arrangements, with only one practical and preferred embodiment being illustrated in the accompanying drawings, as required. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    Preferred embodiments of the invention are described below with reference to the following accompanying drawings: 
           [0012]      FIG. 1  is an elevation view of one embodiment of a mobile tower system which may be utilized in practicing the invention; 
           [0013]      FIG. 2  is a top view of the mobile tower system illustrated in  FIG. 1 ; 
           [0014]      FIG. 3  is a second side elevation view of the mobile tower system illustrated in  FIG. 1 ; 
           [0015]      FIG. 4  is an elevation view of the mobile tower system illustrated in  FIG. 1  with the tower partially rotated toward the vertical position; 
           [0016]      FIG. 5  is an elevation view of the mobile tower system in  FIG. 1  with the tower having been rotated to the vertical position and before it is expanded; 
           [0017]      FIG. 6  is a close up perspective view of the various components of the mobile tower system illustrated in  FIG. 1  which are part of the expansion of the tower system; 
           [0018]      FIG. 7  is a perspective detail view of the base of the framework of the mobile tower system illustrated in  FIG. 1 ; 
           [0019]      FIG. 8  is a front perspective view of the framework and trailer of the mobile tower system illustrated in  FIG. 1 ; 
           [0020]      FIG. 9  is an elevation view of the mobile tower system illustrated in  FIG. 1 , in its expanded state with an antenna mounted thereon; 
           [0021]      FIG. 10  is an end view of one embodiment of a cylinder pin or spring pin that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 ; 
           [0022]      FIG. 11  is a front elevation view of the spring pin illustrated in  FIG. 10 ; 
           [0023]      FIG. 12  is a second end view of the spring pin illustrated in  FIG. 10 ; 
           [0024]      FIG. 13  is a front elevation view of the spring illustrated in  FIG. 10 , with the handle partially rotated; 
           [0025]      FIG. 14  is a front elevation view of the spring pin illustrated in  FIG. 10 , with the handle more fully rotated; 
           [0026]      FIG. 15  is a front elevation view of the spring pin illustrated in  FIG. 10 , with the handle more fully rotated; 
           [0027]      FIG. 16  is a front elevation view of the spring illustrated in  FIG. 10 , with the handle fully rotated to its fully biased position; 
           [0028]      FIG. 17  is a rear view of the embodiment of the mobile tower system as illustrated in  FIG. 1 , only wherein a hydraulic cylinder is internally provided in the towers to drive the expansion of the tower to its fully extended vertical position; 
           [0029]      FIG. 18  is a rear elevation view of the embodiment of the mobile tower system as illustrated in  FIG. 17 , showing the hydraulic cylinder raising or extending the fifth tower structure relative to the fourth tower structure; 
           [0030]      FIG. 19  is detail  19  from  FIG. 18 ; and 
           [0031]      FIG. 20  is cross-sectional view  20 - 20  from  FIG. 19 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0032]    Many of the fastening, connection, manufacturing and other means and components utilized in this invention are widely known and used in the field of the invention described, and their exact nature or type is not necessary for an understanding and use of the invention by a person skilled in the art or science; therefore, they will not be discussed in significant detail. Furthermore, the various components shown or described herein for any specific application of this invention can be varied or altered as anticipated by this invention and the practice of a specific application or embodiment of any element may already be widely known or used in the art or by persons skilled in the art or science; therefore, each will not be discussed in significant detail. 
         [0033]    The terms “a”, “an”, and “the” as used in the claims herein are used in conformance with long-standing claim drafting practice and not in a limiting way. Unless specifically set forth herein, the terms “a”, “an”, and “the” are not limited to one of such elements, but instead mean “at least one”. 
         [0034]    As will be appreciated by those of reasonable skill in the art, there are numerous embodiments to this invention, and variations of elements and components which may be used, all within the scope of this invention. 
         [0035]      FIG. 1  is an elevation view of one embodiment of a mobile tower system which may be utilized in practicing the invention.  FIG. 1  illustrates a mobile tower system  100  with trailer  101 , trailer framework  102 , trailer wheels  103  and outriggers  104  providing expandable lateral support for the mobile tower system when the tower  108  is in its fully extended position. The outriggers  104  include ground contacts  105  which start in the upward position and are moved downward once the outriggers  104  are in their fully extended lateral position to provide lateral support for the trailer  101 . 
         [0036]    It will be appreciated by those of ordinary skill in the art that the ground contacts  105  may be connected to outriggers  104  in any one of a number of different ways, such as by hydraulic means or manual to allow the ground supports to come in firm contact with the ground to provide the necessary support. Similarly it will be appreciated by those of ordinary skill in the art that the outriggers  104  can be extended laterally in any one of a number of different ways, including manually or hydraulically, among others, in order to provide the lateral support desired for the particular mobile tower system  100  application. The wheels  103  are in contact with ground  129  and it is intended that each of the four outriggers  104  will provide ground supports  105  which are also in contact with ground  129 . 
         [0037]      FIG. 1  further illustrates a tower framework  106  mounted to trailer  101  to provide the structure which supports the tower  108  and allows it to be rotated into the vertical position for expansion and use. It will be appreciated by those of ordinary skill in the art that the framework may be any one of a number of different conditions all within the contemplation of this invention, as long as it provides the support for the tower  108  on the trailer  101 , and facilitates the rotation of the tower  108  with respect to the framework  106 , as illustrated by arrow  110 . 
         [0038]    The tower  108  includes step pegs  118  which may be bolts on the side of the tower to provide a step for operator to climb up the tower  108  when it is in the vertical position. 
         [0039]    The tower  108  will be provided in a number of different sections, each one of which starting with the second fits within the first and so on successively so that the tower components fit within the preceding tower component to provide for the expansion and the contraction of the tower  108 . First tower structure  109  includes an internal cavity in which second tower structure  111  slidably fits, and second tower structure  111  has an internal cavity into which third tower structure  112  slides. Similarly third tower structure  112  has an internal cavity into which fourth tower structure  113  slides and fourth tower structure  113  includes an internal cavity into which fifth tower structure  114  slides. The tower  108  is intended to be rotated from the horizontal position shown in  FIG. 1  to a vertical position as shown in later Figures, and any one of a number of different ways may be utilized to accomplish this rotation.  FIG. 1  for example shows winch line  120  which would be attached to the first end to the lower portion of first tower structure  109  to pull it downwardly about axis  96  as indicated by arrow  110  to move it to a vertical location. As shown in later figures, rods are inserted into rod apertures  99  once the tower is rotated to the substantially vertical position to prevent it from rotating back to the horizontal position. 
         [0040]    In one embodiment of the invention, the tower structure may be square in cross sectional configuration with first tower structure  109  being eight inches, second tower structure  111  being seven inches, third tower structure  112  being six inches, fourth tower structure  113  being five inches and fifth tower structure  114  being four inches. These dimensions provide for the respective tower section structures to slide within one another to provide the expansion function. 
         [0041]    Chain  115  may be attached to the particular tower structure which is being raised once the tower  108  is in the vertical position and then attached to the next tower structure to be raised and so on until the tower  108  is in the fully extended position. 
         [0042]      FIG. 2  is a top view of the mobile tower system illustrated in  FIG. 1 .  FIG. 2  illustrates the mobile tower system shown in  FIG. 1 , with the outriggers  104  in their fully extended position. Cranks  149  are shown on outriggers  104  to provide a screw driven mechanism for the ground supports  105  to be extended downward to make contact with the ground and then to later be retracted upward when the outriggers  104  are to be contracted for travel. The movement of the ground supports  105  may be utilized to level the trailer or to place the tower  108  in a desired vertical position.  FIG. 2  further illustrates trailer framework  102 , first tower structure  109 , second tower structure  111 , third tower structure  112 , fourth tower structure  113 , fifth tower structure  114 , chain  115  and step pegs  118  attached to first tower structure  109 . The trailer also includes a deck  134  as a trailer base or working platform.  FIG. 2  further illustrates tower framework  106 . 
         [0043]      FIG. 3  is a second side elevation view of the mobile tower system illustrated in  FIG. 1 .  FIG. 3  illustrates a mobile tower system  100  with trailer  101 , trailer framework  102 , trailer wheels  103  and outriggers  104  providing expandable lateral support for the mobile tower system when the tower  108  is in its fully extended position. The outriggers  104  include ground contacts  105  which start in the upward position and are moved downward once the outriggers  104  are in their fully extended lateral position to provide lateral support for the trailer  101 . It will be appreciated by those of ordinary skill in the art that the ground contacts  105  may be connected to outriggers  104  in any one of a number of different ways, such as by hydraulic means or manual to allow the ground supports to come in firm contact with the ground to provide the necessary support. Similarly it will be appreciated by those of ordinary skill in the art that the outriggers  104  can be extended laterally in any one of a number of different ways, including manually or hydraulically, among others, in order to provide the lateral support desired for the particular mobile tower system  100  application. The wheels  103  are in contact with ground  129  and it is intended that each of the four outriggers  104  will provide ground supports  105  which are also in contact with ground  129 . 
         [0044]      FIG. 3  further illustrates a tower framework  106  mounted to trailer  101  to provide the structure which supports the tower  108  and allows it to be rotated into the vertical position for expansion and use. 
         [0045]    The tower  108  includes step pegs  118  which may be bolts on the side of the tower to provide a step for operator to climb up the tower  108  when it is in the vertical position. 
         [0046]    The tower  108  will be provided in a number of different sections, each one of which starting with the second fits within the first and so on successively so that the tower components fit within the preceding tower component to provide for the expansion and the contraction of the tower  108 . First tower structure  109  includes an internal cavity in which second tower structure  111  slidably fits, and second tower structure  111  has an internal cavity into which third tower structure  112  slides. Similarly third tower structure  112  has an internal cavity into which fourth tower structure  113  slides and fourth tower structure  113  includes an internal cavity into which fifth tower structure  114  slides. The tower  108  is intended to be rotated from the horizontal position shown in  FIG. 3  to a vertical position as shown in later Figures, and any one of a number of different ways may be utilized to accomplish this rotation.  FIG. 3  for example shows winch line  120  which would be attached to the first end to the lower portion of first tower structure  109  to pull it downwardly about axis  96  as indicated by arrow  110  to move it to a vertical location. 
         [0047]    In one embodiment of the invention, the tower structure may be square in cross sectional configuration with first tower structure  109  being eight inches, second tower structure  111  being seven inches, third tower structure  112  being six inches, fourth tower structure  113  being five inches and fifth tower structure  114  being four inches. These dimensions provide for the respective tower section structures to slide within one another to provide the expansion function. 
         [0048]    Chain  115  may be attached to the particular tower structure which is being raised once the tower  108  is in the vertical position and then attached to the next tower structure to be raised and so one until the tower  108  is in the fully extended position. 
         [0049]      FIG. 4  is an elevation view of the mobile tower system illustrated in  FIG. 1  with the tower partially rotated toward the vertical position.  FIG. 4  illustrates a tower  108  as being rotated per arrow  130  and about axis  96  as illustrated by arrow  110 . Winch lines  120  are shown in the taut position as they are pulling the lower portion of first tower structure  109  downwardly to provide the rotation. 
         [0050]    The components illustrated in  FIG. 4  are the same as  FIG. 1  and have like numbers and will not therefore again be discussed in detail with respect to  FIG. 4 . 
         [0051]    It will be appreciated by those of ordinary skill in the art that while it is preferred that outriggers  104  be in their fully extended position and ground supports  105  be in contact with the ground  129 , this may not be necessary in some embodiments of the invention while the rotation of the tower  108  is being accomplished to place the tower  108  from a horizontal into its vertical position. First tower structure  109  will fit between components of framework  106 , though any one of a number of other configurations may be utilized so long as the first tower structure  109  is secured to the tower framework  106 .  FIG. 4  further shows how the first tower structure rotates about axis  96  when being rotated from a substantially horizontal position to a substantially vertical position. 
         [0052]      FIG. 5  is an elevation view of the mobile tower system  100  in  FIG. 1  with the tower  108  having been rotated to the vertical position and before it is expanded.  FIG. 5  shows the mobile tower system  100  wherein the lower  108  has been rotated to its vertical position and secured in that position to tower framework  106 .  FIG. 5  illustrates axis  96  around which the tower was pivoted, and how rod  98  is inserted through rod apertures  99  to secure the tower and prevent it from rotating back toward the horizontal position.  FIG. 5  is shown with a break in the tower  108  and not proportional as indicated at section  135  to provide a better illustration.  FIG. 5  further shows trailer  101 , trailer framework  102 , ground  129 , trailer wheels  103  and the multiple tower structures each slid within one another in the fully contracted position. 
         [0053]      FIG. 6  is a close up perspective view of the various components of the mobile tower system illustrated in  FIG. 1  which are part of the expansion of the tower system.  FIG. 6  illustrates the individual components of tower  108 , first tower structure  109 , second tower structure  111 , third tower structure  112 , fourth tower structure  113 , fifth tower structure  114 , which each successively is slid within the preceding tower in the contracted state. Step pegs  118  are shown attached to first tower structure  109 . Arrow  158  illustrates how second tower structure  111  slides relative to first tower structure  109 . Arrow  159  illustrates how third tower structure  112  slides relative to and within second tower structure  111 . Arrow  160  illustrates how fourth tower structure  113  slides with respect to and within third tower structure  112  and arrow  161  illustrates how fifth tower structure  114  slides relative to and within fourth tower structure  113 . Guide wire connectors  154 ,  155 ,  156  and  157  are shown respectively attached to second tower structure  111 , third tower structure  112 , fourth tower structure  113 , fifth tower structure  114  and provide eyelets to which guide wires can be attached and then secured to the ground at an extended position to provide support once the tower  108  is in its vertical position and fully extended. 
         [0054]    Aperture  97  in fifth tower structure  114  may provide an aperture in which a component from an antenna or a mounting system for an antenna may be inserted to more easily secure an antenna to the fifth tower structure  114 . 
         [0055]    It will also be appreciated by those of ordinary skill in the art that while five tower structures are shown in this embodiment, that any number of tower structures may be provided within the contemplation of this invention, with this being one preferred way to practice the invention. Similarly, guide wire support  162  is shown attached to second tower structure  111 , guide wire attachment  163  is shown attached to third tower structure  112 , guide wire attachment  164  is shown attached fourth tower structure  113  and guide wire attachment  166  is shown attached to fifth tower structure  114 . 
         [0056]      FIG. 6  illustrates spring pins  150 ,  151 ,  152  and  153 . Spring pin  150  is shown attached to first tower structure  109 , second spring pin  151  is shown attached to second tower structure  111 , third spring pin  152  is shown attached to third tower structure  112 , fourth spring pin  153  is shown attached to fourth tower structure  113 . These spring pins are leaf springs as shown in later Figures and provide a mechanism for providing both relative movement and securement of each respective tower structure to the adjacent tower structure. Arrow  165  illustrates how the handle on the spring pin  151  may rotated to retract the pin portion (not shown in  FIG. 6 ). 
         [0057]      FIG. 7  is a perspective detail view of the base of the framework of the mobile tower system illustrated in  FIG. 1 .  FIG. 7  shows tower framework  106  components relative to first tower structure  109 . Shown mounted on first tower structure  109  is first structure base plate  109   a  which may be attached any one of a number different ways to first tower structure  109  but which may be utilized to attach first tower structure  109  to tower framework  106  by any one of a number of different means, such as the bolts  167  shown. Arrow  168  shows the relative movement of first tower structure  109  relative to framework  106 . 
         [0058]    Framework components  106   a  are shown attached to trailer decking  134  for securing the tower framework  106  to the trailer. Again it will be appreciated by those of ordinary skill in the art this may be accomplished any one of a number of different ways, with no one in particular being required to practice the invention. 
         [0059]      FIG. 8  is a front perspective view of the framework and trailer of the mobile tower system illustrated in  FIG. 1 .  FIG. 8  illustrates trailer  101 , trailer decking  134 , tower framework  106  with floor attachment components  106   a , trailer framework  102 , trailer wheels  103 , outriggers  104  and ground supports  105 .  FIG. 8  shows a pulley and winching arrangement with winch line  120  wherein winch line is routed through pulley  182  and around pulley  181  would provide one of several different mechanism options for moving the tower  108  from horizontal to a vertical position or to any position in between. 
         [0060]    It will also be appreciated by those of ordinary skill in the art that other drive systems such as a hydraulic cylinder, gear driven motor with appropriate attachments to the tower  108 , may be utilized to provide the driving force to rotate the tower  108  with respect to tower framework  106 . 
         [0061]      FIG. 9  is an elevation view of the mobile tower system illustrated in  FIG. 1 , in its expanded state with an antenna mounted thereon.  FIG. 9  shows the mobile tower system  100  illustrated in  FIG. 1  in its fully extended vertical position with an antenna  174  mounted. The height  186  of the tower system can be any one of a number of different heights depending upon the desired application of this mobile tower system  100 .  FIG. 9  illustrates trailer  101  on ground  129  with trailer framework  102 , tower framework, outriggers and ground supports. First tower structure  109 , second tower structure  111 , third tower structure  112 , fourth tower structure  113 , fifth tower structure  114  are shown fixed in their extended position relative to one another respectively to produce the height  186  of the tower system. Spring pin  150  has one or more similar and identical spring pins  150  which secure first tower structure  109  to second tower structure  111 . Second spring pin  151  similarly has one or more other spring pins around the perimeter of second tower structure  111  and secure second tower structure  111  relative to third tower structure  112  in the extended position of third tower structure  112  outside of the interior cavity of second tower structure  111 . Third spring pin  152  is shown mounted on third tower structure  112  and one or more third spring pins  152  may be utilized to secure fourth tower structure  113  relative to third tower structure  112 , as more fully described below. Fourth spring pin  153  is shown mounted on fourth tower structure  113  and it and possibly additional fourth spring pins  153  are utilized to secure fifth tower structure  114  relative to fourth tower structure  113 . 
         [0062]    There are multiple ways which may be utilized to extend each of the tower structures relative to the adjacent tower structure. One way is to use a boom truck and a desirable advantage of this invention is that the boom truck does not need to be able to extend the full height  186  of the mobile tower system, but instead only needs to be able to reach to the height of the top of the second tower structure  111  as shown by height  187  in  FIG. 9 . The sequence which may be utilized to extend the mobile tower system  100  is to secure the first tower structure  109  in the vertical position with the remaining tower structures fully contracted. The boom truck may first then attach to the top of fifth tower structure  114  which is near the top of  109  when all the tower structures are in a contracted position. The boom truck may slide fifth tower structure  114  upwardly within fourth tower structure  113  with the spring pin  153  being in the contracted but biased position. Once the fifth tower structure  114  is slid to a sufficient height the spring pin  153  will pop into an aperture within fifth tower structure  114  thereby securing the extended position of fifth tower structure  114  with respect to fourth tower structure  113 . Again it will be appreciated that one or more spring pins  153  may be utilized around fourth tower structure  113  to mate with and insert into apertures within fifth tower structure  114  to secure it in the position shown. 
         [0063]    Once fifth tower structure  114  is secured relative to fourth tower structure  113 , then the procedure can be repeated to then extend fourth tower structure  113  relative to third tower structure  112  by detaching the boom from fifth tower structure  114  and attaching it to the top of fourth tower structure  113 . Once the boom is attached to the top of fourth tower structure  113  then it may be raised until spring pins  152  click into apertures within fourth tower structure  113  to secure fourth tower structure  113  relative to third tower structure  112 . Again, it will be appreciated that the boom will only have to be at the approximate height  187  to accomplish this since it is doing it one at a time and only one tower structure relative to the next. 
         [0064]    Sequentially then once fourth tower structure  113  is secured relative to third tower structure  112 , the boom can detach from fourth tower structure  113  and attach to the top of third tower structure  112  and follow a similar procedure to allow spring pins  151  to secure third tower structure  112  relative to second tower structure  111 . The same sequence can be followed to secure second tower structure  111  relative to first tower structure  109  and spring pins  150  are utilized to secure second tower structure  111  in its extended position relative to first tower structure  109 . 
         [0065]      FIG. 10  is an end view of one embodiment of a cylinder pin or spring pin that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 .  FIGS. 10-12  illustrate one embodiment of a spring pin that may be utilized in practicing embodiments of this invention. The spring pin  150  being exemplary and referring to the one attached to first tower structure  109 . However, spring pins  151 ,  152  and  153  are similar and the description relative to  150  is used for exemplary purposes in describing this invention. Spring pin  150  has handle  147 , first body position  150   a  and second body portion  150   b  with shoulder mount  148  and pin  146 . Arrow  173  shows how pin  146  may be moved and it may be retracted within first body section  150   a  by the movement of handle  147 , as more fully shown in the series of Figures starting with  FIG. 13  and ending with  FIG. 16  wherein handle  147  is rotated approximately 180° to move pin  146  from its fully extended position as shown in  FIG. 13  to its fully retracted as shown in  FIG. 16 . As second body portion  150   b  is moved relative to first body portion  150   a  by the rotation of handle  147 , an internal spring resists the rotation and further load is imposed by the spring the further pin  146  is retracted. This retraction and loading of the spring places it in a biased status when pin  146  is retracted or fully retracted so that if pin  146  is abutting the exterior of a tower structure and then it is aligned with an aperture in that tower structure, it will release into the aperture and thereby provide securement of the tower structure into which it is released. Pin shaft  171  is shown in various degrees of exposure as handle  147  is rotated relative to the spring pin body  150   a  and an internal spring is attached as described above. 
         [0066]      FIG. 11  is a front elevation view of the pin or spring that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 .  FIG. 11  shows how spring pin  150  may be mounted by shoulder mount  148  to first tower structure  109  through aperture  109   a  in first tower structure  109 . Second tower structure  111  is then shown positioned within first tower structure  109  and second tower structure aperture  111   a  is shown aligned with pin  146  such that pin  146  moved as shown by arrow  173  into second tower structure aperture  111   a . Once pin  146  is inserted in the corresponding second tower structure aperture  111   a  it secures first tower structure  109  relative to second tower structure  111 . If handle  147  is then rotated 180°, pin  146  is completely retracted within spring pin  150  and second tower structure  111  may be moved relative to first tower structure  109 . 
         [0067]      FIG. 14  shows handle  147  rotated approximately 45° from the position shown in  FIG. 11 .  FIG. 15  illustrates handle  147  rotated approximately 90° from the position shown in  FIG. 11 , with the corresponding of the retraction of pin  146  into shoulder mount  148 . In  FIGS. 15-16  it is illustrated how the retraction of pin  146  then provides for the relative or allows the relative movement of second tower structure  111  relative to first tower structure  109 . It should be kept in mind that first tower structure  109  and second tower structure  111  as shown in  FIG. 16  is just a cross section and second tower structure  111  is actually a similarly shaped component within the internal cavity of first tower structure  109 . 
         [0068]    Looking back to  FIG. 6 , it is clear how spring pin  153  for instance may be placed such that the pin therein is in its fully retracted position and when fifth tower structure  114  is slid to the left relative to fourth tower structure  113  that pin  146  would ride on the exterior surface of fifth tower structure  114  until an aperture in fifth tower structure  114  aligns with the pin and the spring is released so that the spring pin  153  inserts into the pin aperture in fifth tower structure  114  thereby securing fifth tower structure  114  relative to fourth tower structure  113 . Similarly, second tower structure  111 , third tower structure  112  and fourth tower structure  113  each have pin apertures therein to align with and receive pins respectively from first spring pin  150 , second spring pin  151 , and third spring pin  152  to provide the relative securement of the respective tower support structures relative to one another. 
         [0069]    While this particular configuration of spring pin is utilized, it will be appreciated by those of ordinary skill in the art that other biasing means for inserting attachment pins between tower structures may be utilized in the contemplation of this invention to provide for the secured expansion of one tower structure relative to another. 
         [0070]    It is an advantage in using these pins a simple way to allow the relative securement of one tower structure relative to another so that the height of equipment, such as a boom truck with a boom that needs to reach the full height  186  as opposed to the reduced height  187  in order to fully extend and erect the mobile tower system  100 . 
         [0071]      FIG. 12  is a second end view of the pin or spring that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 . 
         [0072]      FIG. 13  is a front elevation view of the pin or spring that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 , with the handle partially rotated. 
         [0073]      FIG. 14  is a front elevation view of the pin or spring that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 , with the handle more fully rotated. 
         [0074]      FIG. 15  is a front elevation view of the pin or spring that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 , with the handle more fully rotated. 
         [0075]      FIG. 16  is a front elevation view of the pin or spring that may be utilized in the expansion of the mobile tower system illustrated in  FIG. 1 , with the handle fully rotated to its fully biased position. 
         [0076]      FIG. 17  is a rear view of the embodiment of the mobile tower system as illustrated in  FIG. 1 , only wherein a hydraulic cylinder is internally provided in the towers to drive the expansion of the tower to its fully extended vertical position.  FIG. 17  includes items and components identified with respect to  FIG. 1  and other Figures, and like numbered items or components will therefore not be described in detail again with respect to  FIG. 17 .  FIG. 17  shows hydraulic cylinder  119  in the center of the tower structures and also shows the respective lengths of the tower structures, namely length A for first tower structure, length B for second tower structure, length C for third tower structure, length D for fourth tower structure and length E fifth tower structure. 
         [0077]    It will be appreciated by those of ordinary skill in the art that any one of a number of different lengths may be utilized for any one of the towers sliding within another, with no one in particular being required to practice the invention. It will also be appreciated by those of ordinary skill in the art that any one of a number of different tower structures may be utilized, including 2, 3, 4, 5 or more, within the contemplation of this invention. 
         [0078]    In aspects or embodiments of this invention, a boom truck or crane or other device may be utilized to extend the powers with respect to one another. If it is desired to minimize the size of the boom truck or crane required, the preferred way to raise the towers is to attach the crane or boom truck to the uppermost tower structure first, by means such as chain  115  attached to the tower structure, and then to raise that tower structure to a position where the spring spring pins into a spring pin aperture from the fourth tower structure  113 , which then locks into place in an aperture within fifth tower structure  114 . Once this is locked in the extended position, then the boom or crane can be attached to the next uppermost tower and it can be raised with respect to the one directly beneath it, and so on until the entire tower is raise one section at a time. It will be appreciated by those in the art that a feature or aspect of this invention only requires a boom truck to be able to span the height of two sections, namely the lower section and the section which is being raised at that time, as opposed to requiring a crane to span the entire length of the tower when it is raised. This feature will also be true in later embodiments such as those wherein a hydraulic cylinder is placed within the tower structures and used for the raising of each individual tower. 
         [0079]      FIG. 18  is a rear elevation view of the embodiment of the mobile tower system as illustrated in  FIG. 17 , showing the hydraulic cylinder  119  raising or extending the fifth tower structure relative to the fourth tower structure. Like numbers in  FIG. 18  are the same items or components as in  FIG. 17  and will not therefore be repeated herein. In the embodiment of the invention shown in  FIG. 18  where internal hydraulic cylinder  119  is utilized to raise the respective tower structures with respect to one another, a pin or other mechanism may be placed through apertures in the tubular wall of each, or across each to allow the hydraulic cylinder or top of the cylinder ram to engage it to raise that tower structure. After a given tower structure is raised to its extended position, the hydraulic cylinder ram may then be retracted back down to the next tower structure. Once the hydraulic cylinder is lowered down to or below the top of the next tower structure, a pin may be placed in that tower structure and that particular tower structure may then also be raised. 
         [0080]    The tower structures are raised until the spring pins engage the spring pin apertures on the tower structure within the internal cavity of that tower structure, thereby securely fixing one tower structure relative to an adjacent tower structure from further vertical movement. It will also be appreciated by those of ordinary skill in the art that one or more spring pins may be mounted on a given tower structure to help secure the tower structures with respect to one another, such as two spring pins, three spring pins or four spring pin&#39;s around a given tower. 
         [0081]      FIG. 19  is detail  19  from  FIG. 18 , and shows hydraulic cylinder ram  119  with pin  121  placed through pin apertures in fifth tower structure  114 . The top of the hydraulic ram may include a V-shaped adapter  122  as shown in  FIG. 20  to engage and push on pin  121  to move that tower structure upward. Once a given tower structures such as fifth tower structure  114  is moved in locked into its upward or extended position, then hydraulic cylinder ram  119  may be lowered down to a position below the fourth tower structure  113 , a pin inserted into apertures to then engage or be engaged by the hydraulic cylinder ram  119  and its adapter  122 . If this sequence or procedure is followed sequentially, each tower structure is then extended upward to a position which is fixed relative to the tower structure directly beneath it or directly surrounding it, and then the next in sequence is similarly raised, until the entire tower structure is erected at the desired height. 
         [0082]      FIG. 20  is cross-sectional view  20 - 20  from  FIG. 19 , and shows the hydraulic cylinder ram  119  and adapter  122  in gauging pin  121  to raise fifth tower structure  114  upwardly. Guide wire support  157  includes an aperture through which a guide wire may be attached if additional stabilization is required or desired for that particular tower structure. 
         [0083]    There are alternatives to the use of a boom truck to raise the mobile tower system. One such alternative is the use of an internal hydraulic cylinder wherein a pin or other structure may be placed internally within the internal cavity of the tower structures  111 ,  112 ,  113 ,  114 . If the cylinder is mounted within first tower structure  109  such that it extends up to and interacts with fifth tower structure  114  such that when the ram of the hydraulic cylinder is fully extended it has sufficient length to move the spring pin aperture in fifth tower structure  114  in alignment with fourth spring pin  153  so that fifth tower structure  114  is secured relative to fourth tower structure  113 . Once secured, the ram of the hydraulic cylinder may be retracted and a bolt or other structure then attach to fourth tower structure  113  to go through the same procedure to extend it relative to third tower structure  112 . If this procedure is sequentially followed with respect to pins being placed in the tower structures the entire tower can be erected with one internal hydraulic cylinder and no boom truck or other external equipment is required to practice the invention. 
         [0084]    In compliance with the statute, the invention has been described in language more or less specific as to structural and methodical features. It is to be understood, however, that the invention is not limited to the specific features shown and described, since the means herein disclosed comprise preferred forms of putting the invention into effect. The invention is, therefore, claimed in any of its forms or modifications within the proper scope of the appended claims appropriately interpreted in accordance with the doctrine of equivalents.