Abstract:
A system for automating the casting of concrete panels in which a bed position indicator is fed to a program which compares the bed position to CAD drawings concerning the concrete to be cast and sends the drawing detail for the position of the bed which is then shown on the bed by a laser.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    None. 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable. 
       BACKGROUND OF THE INVENTION 
       [0003]    This invention relates to a concrete casting system. Such systems typically have either a moving bed or a fixed bed on which the concrete panels or planks are formed. In the moving bed systems, a long bed moves on a track past each of the various stations that form the panels. In a fixed bed, the various stations themselves move, such as a hopper that pours concrete onto the bed. 
         [0004]    In either system, it is vital to know the precise location on the bed at any time so that any special handling may be done exactly where it is intended. For example, openings, lifting lugs, cutouts, different insulation and metal reinforcement may all be placed into the beds at differing points. In addition, finishes on the top layer of concrete may vary throughout the bed per the requirements of the customers. In addition, when the cured concrete is to be cut into discrete lengths an exact location must be known on where to cut the concrete panel. 
         [0005]    Typically, an entire casting bed will have a detailed drawing, often on CAD (Computer assisted drafting) which shows the workers where each feature throughout the bed must be placed. This involves giving each of the plant workers the required prints of the bed to be cast so they know exactly where each feature must be added. 
         [0006]    The art described in this section is not intended to constitute an admission that any patent, publication or other information referred to herein is “prior art” with respect to this invention, unless specifically designated as such. In addition, this section should not be construed to mean that a search has been made or that no other pertinent information as defined in 37 C.F.R. § 1.56(a) exists. 
       BRIEF SUMMARY OF THE INVENTION 
       [0007]    The invention provides an automated system for casting concrete panels which takes CAD drawings for a casting bed that covers the features throughout the length of the bed and accurately projects a laser generated image of the drawings over the bed at the exact location corresponding to the CAD drawings. This enables the workers to perform whatever functions are needed at that location on the bed, such as placement of lifting lug points, openings, insulation, and surface finishes. 
         [0008]    The automated system utilizes laser projectors such as those available from LAP GmbH Laser Applikationen of Lueneburg, Germany in combination with its CAD drawings and a positioning system on its concrete casting bed to relate the precise position on the casting bed to the CAD which is tied to the laser projector. This allows the CAD drawings to be projected onto the casting bed as a visible drawing representation such that the workers can immediately see precisely where each and every feature to be included in the concrete which they are about to cast. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    A detailed description of the invention is hereafter described with specific reference being made to the drawings in which: 
           [0010]      FIG. 1  is a top view of a concrete casting bed with the inventive system; 
           [0011]      FIG. 2  is an end, partially perspective view showing the laser system and bed; 
           [0012]      FIG. 3  is an end, partially perspective view similar to that of  FIG. 2  in which the perspective is slightly higher; and 
           [0013]      FIG. 4  is an end view showing a bed positioning mechanism. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0014]    With reference to  FIG. 1 , the form of the invention in which a moving casting bed  10  is employed is shown. Moving casting beds  10  are well known in the art, and typically include a concrete form  12  that may be 900 feet long. The bed  10  has tracks  14  that ride on rails such that the entire bed  10  may be moved down the rails. This allows the bed  10  to be moved to each of the fixed stations, such as for pouring concrete on the bed from an overhead hopper. 
         [0015]    The underside of a typical casting bed  10  is shown in  FIGS. 2-4  in which it will be seen that a mechanism to precisely indicate the exact position on the bed  10  may be generated. The bed position device  20  is used to provide a signal that indicates the exact position of the bed to a known position in the plant. As shown, it involves the addition of a rack  22  to the underside of the casting bed  10 . The rack  22  engages with a pinion  24  which is attached to an encoder  26 . The rack  22  has a fixed rack anchor  28 . The bed  10  includes a bed fixture bracket  30  which together with a linear decoder post  32  and a verneer code readable scale  34  and linear encoded track monitor  36  is able to accurately gauge and report any differences in length of the bed due to tension of the prestressing cables or temperature changes. This allows variations in the casting bed  10  length to be accounted for due to seasonal temperature changes, and stress changes due to prestressing in the bed which over a very long casting bed  10  can be significant. The fixed encoder  26  is fed the bed length information and transmits the exact position on the bed as read by the rack  22 . 
         [0016]    Now that a precise location on the moving casting bed  10  is known, it is possible to use that information in conjunction with the CAD drawings on a computer. An overhead projector laser  40  is mounted to an overhead track  42  above the casting bed  10 . The laser  40  shown is a CAD Pro  2 D laser projector from LAP GmbH Laser Applikationen of Lueneburg, Germany. Such projectors  40  reads common CAD files directly and project a rapidly moving laser line onto the casting bed  10  such that the CAD drawing appears to be “painted” on the surface of the casting bed  10 . Since the casting bed  10  is so long, the CAD drawing is typically displayed in  20  foot increments on the casting bed  10 . While the bed  10  moves, the laser  40  is able to track with the moving bed by virtue of being movably mounted to the overhead track  42 . Thus, the fixed portion of the CAD drawing to be displayed onto the casting bed  10  is able to be kept on the bed while it is moving over the length of the overhead track. The next portion of the CAD drawing is then projected by the laser  40  onto the casting bed as the bed  10  moves. 
         [0017]    It will be seen that the exact position of the moving bed  10  must be known in order for the laser  40  to project the CAD drawing segment onto the proper position of the bed  10 .  FIG. 2  shows the laser  40  projecting the CAD drawings with lines  44  indicating the area in which the pattern may be projected.  FIG. 1  shows the laser field pattern area  46  which moves along with the movement of the laser  40  on its track  42 . 
         [0018]    The invention has been shown in the figures in connection with a moving casting bed. The invention is also used in fixed bed casting, in which the bed is stationary but the various components used in making the concrete panels move about the bed. The laser would simply be on a track above and along the entire length of the bed. The bed positioning device would also be above the bed and relative to the moving components, such as the concrete hopper, etc. 
         [0019]    While this invention may be embodied in many different forms, there are shown in the drawings and described in detail herein specific preferred embodiments of the invention. The present disclosure is an exemplification of the principles of the invention and is not intended to limit the invention to the particular embodiments illustrated. 
         [0020]    This completes the description of the preferred and alternate embodiments of the invention. Those skilled in the art may recognize other equivalents to the specific embodiment described herein which equivalents are intended to be encompassed by the claims attached hereto.