Abstract:
A portable telescoping tower assembly. The assembly includes a tower mounted on a trailer wherein the tower includes a plurality of telescoping sections that extend for use and retract and nest for storage and transportation. At least one cylindrical ram moves the tower between horizontal and vertical positions. A motor extends and retracts the plurality of sections. Each of the sections includes a plurality of external edges with each of the external edges including at least one protruding guide to mate with and receive an adjoining section.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention is directed to a portable, telescoping tower assembly that may be mounted on a standard trailer, vehicle, skid, or barge for rapid deployment to support equipment at desired heights. In particular, the present invention is directed to a portable, telescoping tower assembly including a series of telescoping sections that extend for use and retract and nest together for storage and transportation. 
   2. Prior Art 
   Portable tower assemblies are known and are often used to support equipment at desired heights when rapid deployment is warranted or when circumstances are of a temporary nature which do not justify permanent installation. For example, cellular telecommunications services may be desirable at a sports facility or in disaster situations. Additionally, support of lighting equipment at sporting events may be desirable. Portable towers are also used in military operations for telecommunications and detection equipment. 
   The portable towers are often deployed in adverse conditions, such as desert or swamp locations, which are difficult on moving components. High wind conditions can also twist components of a tower. 
   In one type of portable tower system, a plurality of telescoping sections are vertically movable between a retracted, nested position and an extended position. The cross-section of the sections may be triangular, square, rectangular or other shapes. Although each of the telescoping sections are similar, the sections are progressively smaller in cross-sectional area. According, the sections have progressively decreasing horizontal dimensions. Ball bearings or other bearings may be utilized to permit movement between the sections. The bearings may provide extra weight and cost. Alternatively, if the dimensions are within certain tolerances, the framework of an inner section may ride on the framework of an adjacent section. 
   It is important that the sections be capable of relative movement during extension and retraction of the tower. If the sections become misaligned, the sections may become jammed, and retraction or extension of the sections will be difficult or be prevented. 
   Prior proposals for tower assemblies include the following: 
   Blagg (U.S. Pat. No. 3,494,593) discloses a portable mast moved by an electric motor with triangular sections having a vertical stanchion 100 at each corner. Each stanchion 100 includes a vertical guide 102 forming a vertical channel 104 within which lugs 106 and 108 are adapted to slide. 
   Eklund (U.S. Pat. No. 4,357,785) discloses a telescopic mast with each section having six planar sidewalls. Internal guide grooves 5, 6 and 7 receive guide blocks 8, 9 and 10 made of plastic having a high slidability such as a high molecular polythene alloyed with a lubricant. 
   Walther (U.S. Pat. No. 1,459,123) discloses a telescoping tower with a series of fillers 28 secured to inner sections by rivets 30. 
   Rowan (U.S. Pat. No. 2,715,954) discloses a vehicle mounted tower which may be pivotally raised or lowered. 
   Partlow (U.S. Pat. No. 3,439,467) discloses a telescoping tower with primary guides such as vertically extending grooves 46, 47 and auxiliary guides in the form of elongated plates 51. The tower includes an electrically driven motor 43 with suitable reduction gearing means. 
   Campbell (U.S. Pat. No. 3,958,376) discloses a tower with tower sections, each section being smaller in size than the next adjacent section. Tower sections 130 and 120 have collars 131 and 121 which are provided with rollers 132 and 122 which contact the outer surface of the next adjacent section. 
   Jouffray (U.S. Pat. No. 3,985,234) discloses a boom with telescopic elements slidably engaged within one another having slide shoes 23 which bear against a lower or inner V-shaped leg 18 to self-center the elements with respect to each other. 
   Roberts et al. (U.S. Pat. No. 4,932,176) discloses a telescoping mast system moved between a horizontal stowed position and an upright operating position. 
   Harrel, Jr. et al. (U.S. Pat. No. 5,537,125) discloses a vehicle mounted broadcast antenna tower and a pair of hydraulic pistons 28 that move the tower from horizontal to vertical. 
   Lavin (U.S. Pat. No. 5,557,892) discloses a mast with bearings 100 mounted at the inside of each mast section, to slide up and down the outer mast section. 
   Norwood (U.S. Patent Application Publication No. 2006/0028390) discloses a cell phone telescoping tower raised or lowered from storage to operating position by hydraulic cylinder. 
   Notwithstanding the foregoing, there remains a need to provide a portable, telescoping tower assembly which is simple and cost effective to construct and operate. 
   Accordingly, it would be desirable to provide a portable, telescoping tower assembly with a guide mechanism that will permit efficient and rapid deployment and retraction of the sections of the telescoping tower. 
   It would also be desirable to provide a guide mechanism for adjoining sections of a tower assembly which are simple to construct, efficient to operate, and which does not require any lubrication. 
   It would also be desirable to provide a portable tower assembly with telescoping sections having guides that are easily replaceable. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to a portable telescoping tower assembly which includes a tower mounted on a vehicle or a trailer. The trailer includes framework mounted on a trailer bed having a pair of pivotal connections or pivots, which provide an axis for rotation of a tower frame of the tower. The tower may be moved between a horizontal position for storage and transportation and a vertical position for use by a pair of cylindrical rams which are pivotally attached to the tower frame of the tower offset from the pivots. 
   The tower includes a plurality of telescoping sections with the uppermost sections supporting a bracket for mounting desired equipment. 
   Each of the successive sections are progressively smaller in cross sectional area to permit nesting of the sections. 
   The telescoping sections are moved from the retracted position to an extended position by a direct drive electric motor in communication with a gear reducer and winch mechanism. 
   Each section includes three parallel tubes equally spaced from each other. The outer edge of each tube forms a rail with an external edge to act as a guiding rail for interaction with an adjacent larger section. Additionally, the inner edge of each tube forms a rail with an internal edge to act as a guiding rail. Protruding guides extending from the tubes act as bearing surfaces and guide mechanisms for movement between the sections. A mounting plate is welded or otherwise affixed to a tubular rail. A pair of plastic panes each include a reduced thickness portion. The panels are brought together with the reduced thickness portion sandwiched around the mounting plate and are fastened thereto. An end of each plastic panel is beveled, chamfered, or provided with a radius. When the panels are brought together and joined, the ends form a cupped or radiused surface which will receive the rail of the adjacent section. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a portable telescoping tower assembly constructed in accordance with the present invention in a horizontal, storage and transportation position; 
       FIG. 2  is a perspective view of the portable telescoping tower assembly shown in  FIG. 1  in an upright or vertical position; 
       FIG. 3  is a perspective view of the portable telescoping tower assembly shown in  FIG. 2  with sections extended or deployed for use; 
       FIG. 4  is an enlarged view of portions of the sections of the tower assembly shown in  FIG. 3 ; 
       FIG. 5  is a sectional view taken along section line  5 - 5  of  FIG. 4  and  FIG. 6  is a sectional view taken along section line  6 - 6  of  FIG. 4 ; and 
       FIG. 7  is an exploded view of the protruding guide which is a part of the portable telescoping tower assembly of the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The embodiments discussed herein are merely illustrative of specific manners in which to make and use the invention and are not to be interpreted as limiting the scope of the instant invention. 
   While the invention has been described with a certain degree of particularity, it is to be noted that many modifications may be made in the details of the invention&#39;s construction and the arrangement of its components without departing from the spirit and scope of this disclosure. It is understood that the invention is not limited to the embodiments set forth herein for purposes of exemplification. 
   Referring to the drawings in detail,  FIG. 1  illustrates a perspective view of a portable telescoping tower assembly  10  constructed in accordance with the present invention which is in the horizontal, storage and transportation position. 
   The assembly  10  includes a tower  12  which will be described in detail below. The tower  12  is mounted on a vehicle, such as a truck, or on a trailer  14 . The tower  12  might alternatively be mounted on or in a skid or barge. The trailer  14  includes a plurality of wheels  16 , a hitch  18  for connection with a vehicle (not shown), and a bed  20 . The trailer  14  is no wider than the maximum width permitted on highways and is, accordingly, highly mobile. 
   The trailer  14  also includes a framework  22  mounted on the trailer bed having a pair of pivotal connections or pivots  24 . The pivots  24  provide an axis for rotation of a tower frame  26  of the tower  12 . 
     FIG. 2  illustrates a perspective view of the tower assembly  10  with the tower  12  in an upright position so that the sections may be extended for deployment. 
   The tower  12  is moved between the horizontal position in  FIG. 1  and the vertical position in  FIG. 2  by a pair of cylindrical rams  30  (only one visible in  FIG. 1 ). The cylindrical rams  30  are powered by a hydraulic or pneumatic power supply such as a pump (not shown) and will include controllable valves, all of which are well-known in the art. The cylindrical rams  30  are pivotally attached to the tower frame  26  of the tower  12  offset from the pivots  24  so that when the rams are extended, the tower  12  will rotate about the axis of the pivots  24  to vary the angular position of the tower. 
   The tower  12  includes a plurality of telescoping sections  32 ,  34 ,  36 ,  38 ,  40  and  42  fabricated primarily from metal. The uppermost section  42  supports a bracket  44  for mounting desired equipment, such as cellular telecommunications transceivers (not shown). 
   Each of the successive sections  32 ,  34 ,  36 ,  38 ,  40  and  42  are progressively smaller in cross-sectional area to permit nesting of the sections as seen in  FIGS. 1 and 2 . 
   The telescoping sections are moved from a retracted position shown in  FIG. 2  to an extended position shown in  FIG. 3  by a direct drive electric motor  46  in communication with a gear reducer  50  connected to a chain drive and winch mechanism  52 . A cable  54  is wound around a drum  56  and then to a pulley system on the telescoping sections  32 ,  34 ,  36 ,  38 ,  40  and  42  in order to raise the sections, all as is well known in the art. In one non-limiting example, a 1.5 horsepower direct drive electric motor is used with a 300 to 1 gear reducer. An optional electric generator (not shown) may be mounted on the bed  20  of the trailer. 
     FIG. 3  illustrates a perspective view of the tower assembly  10  with the tower  12  in the extended position with a portion in dashed lines enlarged for clarity.  FIG. 4  illustrates a plan view of the portion of the tower  12  shown in  FIG. 3  and the connection between section  38  and section  40 . 
     FIG. 5  illustrates a sectional view taken along section line  5 - 5  of  FIG. 4  and  FIG. 6  is a sectional view taken along section line  6 - 6  of  FIG. 4 . 
   Each section  32 ,  34 ,  36 ,  38 ,  40  and  42  is constructed in substantially the same way. As seen in  FIGS. 4 ,  5  and  6 , each section includes three parallel tubes equally spaced from each other approximately one hundred twenty degrees (120°) apart to form a triangle in cross-section. For example, section  38  includes tubes  48  while section  40  includes tubes  58 . The outer edge of each tube  58  forms a rail with an external edge to act as a guiding rail for interaction with an adjacent, larger section  38 . For example, the three tubes  58  in section  40  each have external edges which form three rails for interaction with section  38  as best seen in  FIG. 5 . 
   It will be appreciated that the present embodiment includes three equally spaced rails to form a triangle. Four rails in the configuration of a square or rectangle or even other configurations are possible within the spirit and scope of the present invention. 
   Extending between the three equally spaced tubular rails is a connecting structure or webbing  60 . It will be appreciated that other types of connecting structure might be employed. Also extending between the three tubular rails are angle irons  62  and plates  64 . 
   The inner edge of each tube  48  forms a rail with an internal edge to act as a guiding rail. A protruding guide  70  extends in a direction outward from the external edge of each tubular rail  58  of section  40  and mates with the inner edge of each tubular rail  48  of section  38 . 
     FIG. 7  illustrates an exploded view of a portion of the section  38  and the adjoining section  40  of the tower. The protruding guide  70  is exploded for clarity. A mounting plate  72  is welded or otherwise affixed to the tubular rail  48  of section  38  and extends outward therefrom. A pair of plastic panels  74  and  76  each include a reduced thickness portion. The panels may be composed of a thermoplastic polyoxymethylene, such as Delrin™, which has a low coefficient of friction. The panels  74  and  76  are brought together, with the reduced thickness portions sandwiched around the mounting plate  72 , and are fastened with bolts  78 , washers, and nuts  80 . An end  82  of each plastic panel  74  and  76  is beveled, chamfered or provided with a radius. When the panels are brought together, the ends  82  form a cupped or radiused surface which will receive the rail  58  of section  40 . The guides thus provide bearing surfaces for movement of the sections with respect to each other, without lubrication. 
   The present invention provides a relatively narrow and low profile design that permits transportation in a standard 40 foot ocean container. 
   Whereas, the present invention has been described in relation to the drawings attached hereto, it should be understood that other and further modifications, apart from those shown or suggested herein, may be made within the spirit and scope of this invention.