Abstract:
The present invention relates to an apparatus and a method to repair the interior of a vertical structure. The invention includes a telescopic ladder and a knockdown platform that can be deployed and assembled on-site.

Description:
REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims priority to U.S. Provisional Patent Application Ser. No. 61/981,897, filed Apr. 21, 2014, the entire content of which is incorporated herein by reference. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates to telescopic ladder carried by a vehicle. More specifically, it refers to apparatus including a telescopic ladder and knockdown platform that can be deployed and assembled on-site for repairing a vertical structure. 
       BACKGROUND OF THE INVENTION 
       [0003]    There are many ladder lift systems and methods of use. These generally help an operator to reach at a certain height above the ground. U.S. Pat. No. 7,624,844 Alexander discloses a ladder lift system and method of use that includes a specially designed clamp element which is connected between an extension ladder and a pivotable lift rail. The system includes lower ladder support. The system is especially adapted for use in combination with the bed of a transport or pick-up truck. The system and method of use allows a single workman to safely and easily utilize an extension ladder for a wide variety of work and service tasks. However, none of the prior art addresses the problems related to the maintenance of the vertical structures, such as silos, wherein such work is complicated by the fact that the access doors from below are quite small, in some cases on the order of 36 inches in diameter. Metal vertical structures or silos are used for various purposes including the storage of asphalt and other products. On occasion, repairs, including welding repairs, need to be done on the inside of these structures. As such, maintenance personnel must carry ladders and other equipment through the access port, after which it must be set up for use at different height levels, which is a very time-consuming process. 
       SUMMARY OF THE INVENTION 
       [0004]    The present invention recognizes and addresses disadvantages of the prior art constructions and methods. According to one embodiment, the present invention provides an apparatus to maintain a vertical structure such as a silo. The vertical structure has a bottom opening with a maximum bottom width. The apparatus comprises of a telescopic ladder carried by a vehicle. The ladder has a top end and a bottom end. The apparatus further comprises of a knockdown platform adapted to be assembled inside the vertical structure, the platform being removably attachable to the ladder. 
         [0005]    The fully assembled platform has a platform opening enabling an individual to climb through the platform. The apparatus also has a knockdown hoist adapted to be removably attached near the top end of the ladder, which enables equipment and supplies to be brought up through the platform opening to an individual positioned on the platform. The fully assembled platform has a maximum platform width and the maximum platform width is greater than the maximum bottom width. The bottom opening is above the ground. 
         [0006]    The knockdown platform at least includes the following components: a frame forming the platform opening; a plurality of ribs attachable and extendable outwardly from the frame; and a plurality of panels covering the ribs. The apparatus may have the ribs that are radially extendable. The apparatus may have a hand held control device, the device being connected by a wire or by a wireless connection to the hoist. The apparatus may have a ladder that is operated by the hydraulic equipment. 
         [0007]    The present invention also provides a method to maintain a vertical structure. This method comprises of the following steps: providing the apparatus as discussed above; bringing the ladder into a space under the vertical structure; coordinating a position of the ladder relative to a bottom opening of the vertical structure; aligning the ladder in an upright position under the bottom opening; extending the ladder inside the bottom opening; attaching and using the knockdown hoist to bring equipment and supplies to an individual positioned inside the vertical structure; hoisting parts of the knockdown platform inside the vertical structure using the hoist and assembling the platform inside the vertical structure; and completing steps associated with maintaining the vertical structure. This method may be used to perform the associated steps for maintaining the vertical structure that may include welding, repairing, cleaning, painting, restoration, refurbishment, remodeling, or renovating. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is a drawing that shows a telescopic ladder carried by a vehicle near a vertical structure; 
           [0009]      FIG. 2  is a drawing that shows a vehicle and telescopic ladder under a vertical structure; 
           [0010]      FIG. 3  is a drawing that shows a telescopic ladder being positioned under a vertical structure; 
           [0011]      FIG. 4  is a drawing that shows a telescopic ladder being positioned through the bottom opening; 
           [0012]      FIG. 5  is a drawing that shows a telescopic ladder being positioned through the bottom opening; 
           [0013]      FIG. 6  is a drawing that shows a fully positioned telescopic ladder; 
           [0014]      FIG. 7  is a drawing that shows an individual hoisting parts of platform; 
           [0015]      FIG. 8  is a drawing that shows an exploded view of a platform; 
           [0016]      FIG. 9  is a drawing that shows an individual assembling the platform inside the vertical structure; 
           [0017]      FIG. 10  is a drawing that shows an individual hoisting repair equipment; and 
           [0018]      FIG. 11  is a drawing that shows an individual repairing the vertical structure. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0019]    This invention simplifies the process of maintaining or providing repairs to the interior of the vertical structures such as silos by using equipment including a telescoping ladder and knockdown platform that can be deployed and assembled on-site with much faster turnaround.  FIG. 1  shows a vertical structure  190  and an apparatus comprising of a ladder  100  carried by a vehicle  180 . The vertical structure has a bottom opening  200  and the bottom opening  200  being generally above the ground. The bottom opening  200  has a maximum bottom width d 1 .  FIG. 2  shows that the ladder  100  may be positioned under the bottom opening  200  of the vertical structure  190 . The vehicle  180  may be used for transportation and making position adjustments of the ladder  100 . 
         [0020]      FIG. 3  shows that the ladder  100  may be positioned under the bottom opening  200  of the vertical structure  190 . The ladder  100  may be operated by the hydraulic equipment (not shown).  FIG. 4  shows the ladder  100  being positioned through the bottom opening  200 . The end of the ladder  100  facing towards the bottom opening  200  is termed as top end and the opposing end of the ladder  100  is termed as bottom end. 
         [0021]      FIG. 5  further shows continued positioning of the ladder  100  inside the vertical structure  190 .  FIG. 6  shows the fully extended ladder  100  and an individual  170  attaching a knockdown hoist  120  near the top end of the ladder  100 . This hoist  120  is adapted to be removably attached to the ladder  100  and enables the individual  170  to bring equipment and supplies from below and vice versa. A motor (not shown) may operate the hoist  120 . It also shows a pin  110  that may be inserted to secure the position of the ladder  100 . 
         [0022]      FIG. 7  shows an individual  170  hoisting parts of a platform  130  using a control  220 . Control  220  may be connected by a wire  230  or by a wireless connection to the hoist  120 . An individual can attach equipment and supplies to the hoist cable  240 . 
         [0023]      FIG. 8  shows the exploded view of the platform  130 . In accordance with the invention, a platform  130  is assembled above the bottom opening  200  and inside the vertical structure  190 . It comprises of frame  160  that may be secured with a locking pin  150 . The frame  160  is attached with the ladder  100 . The frame  160  may be connected with the rib  145  by using connecting bracket  155 . The rib  145  may be screw-driven to extend the rib  145  radially outward. Once the ribs  145  are connected, an individual  170  can attach panels  140  coving the ribs  145 . The panels  140  may be made from wooden planks, metal sheets or other material. The platform  130  has a central opening that allows an individual  170  to go up or down the ladder  100  to the platform  130 , if needed.  FIG. 9  shows an individual  170  using a drill machine  210  on a screw-driven rib  145  that extends radially outward from the platform  130 . 
         [0024]      FIG. 10  shows an individual  170  using the hoist  120  to bring equipment  250  from below to the platform  130 .  FIG. 11  shows an individual  170  doing welding near the inner wall of the vertical structure  190 . The fully assembled platform  130  has a maximum platform width d 2 . The maximum platform width d 2  is greater than the maximum bottom width dl. Another advantage of this invention is that components are provided in the knockdown form, enabling the platform  130  and hoist  120  to be assembled and disassembled on site. 
         [0025]    This invention also discloses a method to maintain a vertical structure. The method may comprise of the following steps: providing the apparatus as discussed above; bringing the ladder  100  into a space under the vertical structure  190 ; coordinating a position of the ladder  100  relative to a bottom opening  200  of the vertical structure  190 ; aligning the ladder  100  in an upright position under the bottom opening  200 ; extending the ladder  100  inside the bottom opening  200 ; attaching and using a knockdown hoist  120  to bring equipment and supplies to an individual  170  positioned inside the vertical structure  190 ; hoisting parts of a knockdown platform  130  inside the vertical structure  190  using the hoist  120  and assembling the platform  130  inside the vertical structure  190 ; and the individual  170  completing steps associated with maintaining the vertical structure  190 . The necessary steps may include welding, repairing, cleaning, painting, restoration, refurbishment, remodeling or renovating.