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CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority in U.S. Provisional Patent Application No. 61/213,929, filed Jul. 30, 2009, which is incorporated herein by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present disclosed technology relates generally to a rolled door installation device, and in particular a cradle for holding a rolled curtain door and a system for installing the door above an opening. 
         [0004]    2. Description of the Related Art 
         [0005]    Curtain door systems for residential and commercial use provide a movable barrier to cover a window or opening in a wall. The door systems may be manufactured to cover windows or openings having a wide variety of widths and heights. Curtain door systems are used in a variety of applications such as preventing the spread of fire in occupied structures, providing security to protect windows and doorways, and to cover large openings in walls where the use of large paneled doors is cumbersome or impractical such as openings for the passage of vehicles. 
         [0006]    A curtain door system generally includes a curtain door having a series of interlocking slats of metal or plastic that spans an opening. The curtain door mounts above an opening or window on mounting hardware, and during operation is guided into position by guide rails at the periphery of the opening. The mounting hardware may include a pipe or drum that rotates between two head plates, and from which the curtain door is suspended. The interlocking feature of the slats allows the curtain door to be rolled about the pipe or drum when opening or closing the curtain door. Manufacturers typically ship curtain doors with the curtain door wound about the pipe or drum, or connected to the mounting hardware and drive mechanism. However, installation of the curtain door may be performed after installation of the guide rails, pipe, mounting hardware, and drive mechanism. 
         [0007]    Rolled curtain doors are often heavy and awkward to install. Conventional installation methods require suspending the rolled curtain door below the pipe using slings or ropes. Workers pull on the ropes to lift the door up to the pipe for attachment. Workers next ascend ladders and manually adjust the orientation of the rolled door to align the top slat with the pipe, and connect the two. The curtain door is then rolled off of the ropes and onto the pipe. As a result, the conventional tools and process used to install curtain doors is fraught with challenges, especially when installing doors that weigh hundreds of pounds, or used to cover large openings having great height or width. Moreover, the conventional installation process can lead to injury of the workers installing the door because of a need to use body strength and ladders to complete installation. Therefore, there is a need for a curtain door installation system that permits a worker to safely and accurately install a curtain door regardless of the height of the opening the door will cover, and the size and weight of the door. 
         [0008]    Therefore, those who install curtain door systems desire an installation tool that provides an efficient and safe method for installing these systems. The disclosed subject matter provides these features and advantages. 
       SUMMARY OF THE INVENTION 
       [0009]    In accordance with the invention, a rolled curtain door may be supported by an adjustable cradle having rollers, that are configured to support the curtain door and permit rolling of the door thereon to aid in mounting the door to mounting hardware. The cradle has extensions with rollers that may be extended, thereby allowing the cradle to support rolled curtain doors of varying length. The cradle may be mounted on the tines of a fork on a lifting device, such as a forklift or lifting assembly, to raise raising the curtain door up to a mounting position on a wall above a door opening. Optionally, the rollers may be powered by a motor to rotate the door and assist in mounting it to door hardware. 
         [0010]    If desired, particular embodiments may optionally include a lift assembly attached to the cradle. The lift assembly includes a tower extendable by a piston and cylinder unit. The tower has a fork with tines projecting therefrom. The tower is attached to a base having casters for manually rolling the cradle and lift assembly around a worksite. Stabilizers on the base may be used to support and level the assembly when in use. A winch motor with a cable is attached to the tower and may be used to assist in loading a rolled curtain door onto the cradle. Optionally, a hoist attached to the tower may be used to load a rolled curtain door onto the cradle. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The drawings constitute a part of this specification and include exemplary embodiments of the disclosed subject matter illustrating various objects and features thereof, wherein like references are generally numbered alike in the several views. 
           [0012]      FIG. 1  is a rear perspective view of a first alternative embodiment curtain door installation system embodying principles of the disclosed subject matter where a cradle supporting a rolled curtain door is attached to, and elevated by, a lifting device. 
           [0013]      FIG. 2  is a rear perspective view of the curtain door installation system embodying principles of the disclosed subject matter showing the cradle with extensions assemblies extended from a central assembly. 
           [0014]      FIG. 3  is a front elevational view of the cradle attached to a lifting device. 
           [0015]      FIG. 4  is a second alternative embodiment curtain door installation system including a cradle attached to a lift with an integrated hoist. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0016]    As required, detailed aspects of the disclosed subject matter are disclosed herein; however, it is to be understood that the disclosed aspects are merely exemplary of the invention, which may be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art how to variously employ the present invention in virtually any appropriately detailed structure. 
         [0017]    Certain terminology will be used in the following description for convenience in reference only and will not be limiting. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning 
         [0018]    Referring to the drawings in more detail, the reference numeral  101  generally designates a curtain door installation system embodying the principles of the disclosed subject matter. Referring to  FIG. 2 , the system  101  generally includes a cradle  102  having a central assembly  104 , and first and second extension assemblies  152  and  154 . By way of example, and not to be construed as limiting, the system  101  is shown in  FIG. 1  attached to a lift assembly  202 , and elevated, for installing the rolled curtain door  310  above an opening  302  in a wall  304 . A rolled door system generally includes a curtain door  310  attached to a pipe or drum located between two head plates  306 , a drive mechanism for raising and lowering the curtain door  310 , and guide rails for keeping the curtain door  310  aligned with the opening during operation. 
         [0019]    Referring to  FIG. 2 , cradle  102  generally comprises a central assembly  104 , and first and second extension assemblies  152  and  154 . Central assembly  104  includes a cross member  106  having a pair of fork sleeves  108  secured to the underside, and two roller assemblies  114  secured to the top. Cross member  106  may comprise a hollow steel tube with opposite open ends, and having a rectangular cross section for slidably receiving a leg  156  of first or second extension assemblies  152  and  154 . Cross member  106  is the part that supports the roller assemblies  114 , and for mounting first and second extension assemblies  152  and  154 . Fork sleeves  108  comprise a steel tube having a rectangular cross section, and dimensioned to slidably receive the tines of a fork from a lifting device including, but not limited to, lift assembly  202 , a forklift or a lift truck (not shown). Each fork sleeve  108  has an aperture  110  for receiving a locking member such as a locking pin or a set bolt  112  to secure cradle  102  to the fork of the lifting device. Alternatively, fork sleeves  108  may be welded to the fork. 
         [0020]    Each roller assembly  114  includes an arm  116  mounting two rollers that are opposite each other and allow free rotation of the roller thereon. The roller may include, but is not limited to, a metal, plastic, or composite drum, wheel, or tube, preferably a wheel  120  having a rubber contact surface. Wheels  120  are mounted on arm  116  by a vertical support  115 , wherein the rotational axis of wheel  120  is perpendicular to arm  116 , and wheel  120  is spaced a sufficient distance apart as to cradle a rolled curtain door  310 . Although a wheel  120  is shown and described, any suitable roller or rollers may be used with cradle  102  that permits free rotation of the rolled curtain door  310  thereon. Roller assemblies  114  are mounted with arm  116  perpendicular to cross member  106 , thereby supporting rolled curtain door  310  parallel to cross member  106 . The fork sleeves  108 , cross member  106 , vertical support  115 , and roller assemblies  114  are secured by welding, or alternatively, by fasteners such as a nut and bolt combination. 
         [0021]    Cradle  102  may suitably function with or without first and second extension assemblies  152  and  154 . Extension assemblies  152  and  154  may be connected to central assembly  104  when supporting an especially wide or heavy curtain doors  310 . First extension assembly  152  includes leg  156  mounting roller assembly  114  at one end. Leg  156  comprises a solid or hollow steel tube having a rectangular cross section adapted for insertion into cross member  106 . Roller assembly  114  may be secured to leg  156  by a pair of U-bolts  158 , nuts  160 , and a plate  162 , or alternatively by welding. 
         [0022]    Second extension assembly  156  is generally identical to first extension assembly  152  and therefore will not be described. Leg  146  end opposite roller assembly  114  is inserted into the open end of cross member  106  with roller assembly  114  facing up, and are slid in and out as needed to position first and second roller assemblies  114  under the rolled curtain door  310 . 
         [0023]    Cradle  102  may optionally be powered by a motor  276  that can rotate wheels  120  thereby rotating the rolled curtain door  310  thereon when mounting the curtain door  310  above an opening. Roller assemblies on cross member  106  may be connected by a shaft  174  having a driven sprocket  172 . Driven sprocket  172  is connected to a drive sprocket  176  on motor  276  by a chain  178 . Motor  276  is mounted on either lift assembly  202  or cross member  106 , preferably lift assembly  202 . Motor  276  may be an electrical motor powered by a suitable electrical power supply, or a hydraulic motor powered by an complimentary power source. 
         [0024]    In use, cradle  102  is mated to a lifting device having a pair of forks projecting therefrom. The forks are inserted into fork sleeves  108 , and cradle  102  is secured to the forks by tightening set bolts  112  in apertures  110 . First and second extension assemblies  152  and  154  are adjusted or removed, as needed, to properly support a rolled curtain door  310 . A curtain door  310  is then loaded onto cradle  102 , and cradle  102  is then raised up to the proper height above an opening where the rolled curtain door  310  is attached to the installed door mounting hardware such as a pipe or drum. After the rolled curtain door  310  is attached to the mounting hardware, roller assemblies  114  allow free rotation of the curtain door  310  off of the cradle  102  as the curtain door  310  is rolled onto the pipe or drum, or motor  276  may be engaged to rotate wheels  120  to assist in transferring the rolled curtain door  310  to the door mounting hardware. 
         [0025]    Occasionally a rolled curtain door  310  may already be attached to mounting hardware and a drive mechanism. Therefore, although a rolled curtain door  310  is described, cradle  102  may be used to install a rolled curtain door above a doorway when the rolled curtain door already has its mounting hardware installed using the same process describe above. 
         [0026]    Supporting the rolled curtain door  310  with cradle  102 , and using roller assemblies  114  to transfer the curtain door  310  to the mounting hardware avoids the perils previously encountered when installing curtain doors. Namely, workers can avoid use of straps, step ladders, and body strength currently necessary to suspend and raise heavy curtain door below its mounting hardware. This provides workers with a tool to safely and accurately install a curtain door regardless of the height or location of the mounting hardware, and the size or weight of the door. 
         [0027]    A curtain door installation system comprising a first alternative embodiment curtain door installation system  201  is shown in  FIGS. 1 and 2 , and includes a cradle  102  attached to lift assembly  202 . Lift assembly generally comprises a tower  252  connected to a base  204 . The generally rectangular base  204  includes a frame  206  constructed of tubular members having a rectangular cross section. Frame  206  comprises a rectangle having front and rear members  208  and  210 , and interconnecting side members  212  and  214 . The ends of front and rear members  208  and  210  are joined to their respective side members  212  and  214  in a conventional manner such as by welding. Base  204  is supported by casters  216  secured to frame  206  allowing lift assembly  202  to be rolled around a worksite by a worker. 
         [0028]    A deck  218  is secured to frame  206  and provides a mounting surface for two deck ribs  220 . Each deck rib  220  is located on top of deck  218  adjacent to a side member  212  and  214 . Ribs  220  comprise a solid or hollow steel tube having a rectangular cross section, and traverse deck  218  from front to back adding rigidity to base  204 . The front and rear of each rib  220  provides a mounting surface for a stabilizer  222  used to bias against the surface supporting lift assembly  202 , thereby stabilizing and holding lift assembly  202  when in use. Stabilizer  222  may be a conventional manually-operated stabilizer, or a mechanical stabilizer operated using electric or hydraulic power. 
         [0029]    Tower  252  generally comprises an extendable mast  254  that raises and lowers a fork  266 . Mast  254  is centered at the rear of base  204  and secured thereto by welding. Mast  254  is further secured to base  204  by a heel  256  that is secured to both deck  218  and mast  254  by welding, completing formation of a rigid box-like structure that adds further stability to the connection between base  204  and mast  254 . Mast  254  is further stabilized by angular trusses  260  secured to mast  254  at one end, and base  204  at the other end by welding. A handle  262  on the rear of each truss  260  permits a worker to manually maneuver lift assembly  202 . 
         [0030]    Mast  254  comprises interlocking rails supporting a carriage  264  and a forward-facing fork  266 . Mast  254  functions in a similar manner as those found on a forklift truck for raising and lowering carriage  264  and fork  266 . Mast  254  is raised and lowered by a piston and cylinder unit (p-c unit)  268  connected at one end to base  204  and at another end to mast  254  by a chain. P-c unit  268  communicates with a reservoir  270  via a valve  272  and hose  274 . P-c unit  268  may function using a pneumatic system or a hydraulic system, preferably a pneumatic system. Actuation of valve  272  to a first position extends p-c unit  268  and raises fork  266 . Actuation of valve  272  to a second position ceases movement of p-c unit  268 . Actuation of valve  272  to a third position withdraws p-c unit  268  and lowers fork  266 . 
         [0031]    A winch motor  226  winds-up and lets out a cable  228  having a hook  230  for connecting to a rolled curtain door  310 . Cable  228  passes through a guide  232  keeping cable  228  aligned with winch motor  226  and a wheel  234  disposed at the top of the mast  254 . Wheel  234  allows for cable  228  to roll on when lifting a rolled curtain door  310  onto cradle  102 . 
         [0032]    In use, curtain door installation system  201  provides for installation of a rolled curtain door  310  without the need of a forklift truck. Cradle  102  is attached to fork  266  of the lift assembly  202  in the same manner as described above. First and second extension assemblies  152  and  154  are adjusted or removed as needed depending on the size or weight of the rolled curtain door  310 . After loading a rolled curtain door  310  onto cradle  102  using cable  228  and winch  226 , lift assembly  202  may be freely rolled across a surface. Using handles  262 , a worker can manually position lift assembly  202  and curtain door  310  below an opening to be covered. After engaging stabilizers  222  to immobilize and level lift assembly  202 , a worker actuates valve  272  to the first position to raise fork  266  and cradle  102 . When cradle  102  has reached the proper height to offload the rolled curtain door  310  to the mounting hardware, valve  272  is moved to the second position stopping movement of cradle  102 . After the curtain door  310  is offloaded, valve  272  is moved to the third position permitting cradle  102  to be lowered to the ground. 
         [0033]    A curtain door installation system comprising a second alternative embodiment curtain door installation system  401  is shown in  FIG. 4 , and includes cradle  102  and lift assembly  202  as described above, and further including hoist  402 . Hoist  402  is attached to the top of tower  252  for assisting in loading a rolled curtain door  310  onto cradle  102 . Hoist  402  generally includes a boom  404  that pivots atop tower  252 , and a p-c unit  418  for raising and lowering boom  404 . Boom  404  extends forward from the rear of lift assembly  202  across the top of tower  252 , terminating in front of lift assembly  202 . Boom  404  may comprise a hollow steel tube having a rectangular cross section. Boom  404  pivots about a bracket  408  extending from the top of tower  252 . P-c unit  418  attaches at one end to the rear of boom  404 , and at another end to tower  252 . P-c unit  418  may function in a similar manner, and use like components, as p-c unit  268  described above. A hook  406  at the forward end of boom  404  allows for connection of a chain  410 . Straps  414  may be wrapped around the rolled curtain door  310  and connected to the free end of chain  410  by a cable  412 . Optionally, electrically-powered lights  416  may be attached to tower  252  providing illumination of cradle  102  and workspace. 
         [0034]    In use, the rolled curtain door  310  is connected to the hoist  402  as described above. Actuation of p-c unit lifts the rolled curtain door  310  off of the ground or a vehicle. Workers may then guide the rolled curtain door  310  over cradle  102  and lower boom  404  thereby placing the door  310  between wheels  120  of the cradle  102 . Rolled curtain door  310  is then disconnected from hoist  402 , and raised into position on cradle  102  for installation. 
         [0035]    It will be appreciated that the components of cradle  102  and installation systems  101 ,  201 , and  401  may be used for various other applications. Moreover, cradle  102  and installation systems  101 ,  201 , and  401  may be fabricated in various sizes and from a wide range of suitable materials, using various manufacturing and fabrication techniques. 
         [0036]    It is to be understood that while certain aspects of the disclosed subject matter have been shown and described, the disclosed subject matter is not limited thereto and encompasses various other embodiments and aspects.

Summary:
A cradle for supporting and installing a rolled curtain door comprises rollers configured to support, and permit rolling, of a rolled curtain door thereon. Extensions with rollers permit the cradle to support rolled curtain doors of varying length. A motor may be connected to the rollers to assist in rotating the door. The cradle may be mounted on the tines of a fork on a lifting device. A lift assembly having a tower and base may be attached to the cradle for manually positioning, and mechanically elevating the cradle and door when installing the door. The tower is extended by a piston-and-cylinder unit. A winch motor and cable, or a boom hoist attached to the tower may be used to load a door onto the cradle.