Abstract:
A track dog with removable parts. Embodiments describe one or more of the following features. In one embodiment, the size of the receiver for the knife shaped piece can be variable. Another embodiment describes an improved technique of holding the cable that is run under the floor. Yet another embodiment describes a device where the cable attachment mechanism are set in a location that line up with the openings in the floor to allow tightening without opening the floor. Another aspect describes a special through hole so that cable can be run through the device, e.g., to connect to another track dog.

Description:
[0001]    This application claims priority from provisional application No. 61/261,264, filed Nov. 13, 2009, the entire contents of which are herewith incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    In a stage environment, it may be useful to move scenery. Often, a deck track is used to move the scenery, where the deck track is placed in the floor, and a “dog” extends from the machinery into the floor area. A winch is used to move one or more cables that run under the floor in order to move the scenery along the track. 
       SUMMARY 
       [0003]    An embodiment describes a special deck track dog which has a number of different features. 
         [0004]    Embodiments describe one or more of the following features. In one embodiment, the size of the receiver for the knife shaped piece can be variable. 
         [0005]    Another embodiment describes an improved technique of holding the cable that is run under the floor. 
         [0006]    Yet another embodiment describes a device where the cable attachment mechanism are set in a location that line up with the openings in the floor to allow tightening without opening the floor. 
         [0007]    Another aspect describes a special through hole so that cable can be run through the device, e.g., to connect to another track dog. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIGS. 1A and 1B  show use of the improved deck track dog within a deck of the stage; 
           [0009]      FIG. 2  shows a plan view of the track dog according to an embodiment; 
           [0010]      FIG. 3  shows a front view of an embodiment; 
           [0011]      FIG. 4  shows a side view of an embodiment; 
           [0012]      FIGS. 5A-5D  show the different grips which can be used to grip the cable according to the embodiment; and 
           [0013]      FIG. 6  shows a plan view of the dog “ears” that can be used according to embodiments. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    A new universal deck track dog is described. An embodiment has advantages over many existing items including: changeable length “ears” that normally are permanently welded, the ability to clamp to four sizes of cable with changeable grips compared to only a single cable choice, the ability to loosen the grip and slide the dog in the track and then retighten (a feature which others cannot easily do), a return cable bore for cable that travels through the bore supporting a second dog operating in the same track, and accessory mounting holes for use with changeable shoes and sleds. Embodiments as described herein may carry out one or more of these features. 
         [0015]    An embodiment is shown in  FIGS. 1A and 1B .  FIG. 1A  shows a side view showing a piece of scenery  100  that is movable on the stage. The scenery  100  is mounted on the base  102 . A portion of the scenery mates with the stage, and is movable along the track. The track dog  120  is shown connected to cables  122 ,  124  to a winch  130  that drives the cable. This allows the cable to be moved in the direction of the arrows  123 , thereby moving the scenery back and forth along the track as desired. The scenery includes a blade  105  that is rigidly attached thereto. The blade has a width shown as  106 . The width is formed between inner surfaces of two holding portions on the dog, shown generically as  125  and  126 . The holding portions also define an area therebetween shown as  127 . 
         [0016]      FIG. 1B  shows the dog  120  under the stage floor  150 . The dashed line portions of the dog  120  represent the body of the dog as under the stage floor. It can be seen that a portion of the dog  120 , shown in  FIG. 1B  as  160 , is accessible through the stage floor. That portion includes a number of set screws  162 ,  163  as described herein. 
         [0017]      FIG. 2  shows a detailed plan view of the dog device. The dog includes a body  200  which includes a receiver  210  for a knife blade from scenery or other device to be moved along the track. The receiver  210  includes first and second ears with a first ear  212  on one side of the opening  200  and a second ear  216  on the other side of the opening  214 . The space between the ears defines the size of the opening for the knife that is attached to the scenery. 
         [0018]    In an embodiment, this can be sized to hold a standard 2 inch knife. 
         [0019]    The dog also includes first and second cable locations, including a first cable conduit location  220  shown with the cable  221  therein. The cable  221  is held by cable grippers at the locations  230  and  231  as described herein. Set screws  240 ,  241 ,  242 ,  243 ,  244  are used to hold the cable in place. The cable is run through the cable conduit  220  at an off-center location. The receiver  210  is at the center of the device. Another off-center location, which is symmetric to the off-center location of cable conduit  220 , forms a second cable conduit  225 . A cable can pass through the second conduit area  225  without being held by the dog, and therefore can pass freely through it. For example, in one embodiment, there can be two dogs in the same track, with the cable for the further-placed dog passing through the second conduit area  225  of the closer-placed dog. 
         [0020]      FIG. 3  illustrates a front view of the track dog body. This shows the dog ears  212 ,  216  which are spaced by 2 inches to form the opening  214 . The ears also have a height shown generally as  218 , where the height is from the bottom of the ear to the top of the ear. In the embodiment, different ears can be used to define different heights and the ears are removable and replaceable to put different ears with different heights on the dog. 
         [0021]      FIG. 3  shows the winch cable  320  being held between first and second grippers  330 ,  335 . The grippers have, as explained herein, serrated contact surfaces shown as  331  that generally hold the cable along a certain length of the cable. In an embodiment, the grippers are replaceable. Different thickness grippers can be used to hold different amounts of the cable. 
         [0022]    Set screws  240 ,  241  and  242  are also shown in countersink holes, and as explained herein are in a location so that they can be tightened through the opening in the stage without opening the stage itself. More generally, however, the set screws can be any device which increases and decreases the tightness of the grippers against the cable. 
         [0023]      FIG. 4  shows a side on view of the device, showing the dog ears  212 , the cable  221  and grippers  330  and  335  holding the cable therebetween, as well as the second cable conduit  225  with cable passing therethrough without being gripped. 
         [0024]      FIGS. 5A-5D  show the different grips which can be used according to the present system, to grip the cable in different ways. Each of the grips are substantially 2 inches in length, to hold the cable over that 2 inch length. However, different grips have different thicknesses. For example,  FIG. 5A  shows a first grip that is intended for gripping ⅛ inch cable. This grip  500  has a thickness  502  so that the distance between two of the grips is appropriate for gripping the ⅛ inch cable. 
         [0025]    In a similar way, the other grips are intended for gripping different cables, with grip  505  shown in  FIG. 5B  being for ¼ inch cable, grip  510  in  FIG. 5C  being for 3/16 cable and grip  515  being a 5/16 gripper. Note that each of the grips include an indented portion  501  at the bottom, which interacts with the set screw. 
         [0026]      FIG. 6  shows a detailed view of the dog ear, which is formed from quarter inch steel. Different dog ears can be formed at different thicknesses to be used on different thickness stage floors. 
         [0027]    Although only a few embodiments have been disclosed in detail above, other embodiments are possible and the inventors intend these to be encompassed within this specification. The specification describes specific examples to accomplish a more general goal that may be accomplished in another way. This disclosure is intended to be exemplary, and the claims are intended to cover any modification or alternative which might be predictable to a person having ordinary skill in the art. For example other configurations for other applications are possible. 
         [0028]    Also, the inventor intends that only those claims which use the words “means for” are intended to be interpreted under 35 USC 112, sixth paragraph. Moreover, no limitations from the specification are intended to be read into any claims, unless those limitations are expressly included in the claims. 
         [0029]    Where a specific numerical value is mentioned herein, it should be considered that the value may be increased or decreased by 20%, while still staying within the teachings of the present application, unless some different range is specifically mentioned. 
         [0030]    The previous description of the disclosed exemplary embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these exemplary embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.