Abstract:
A radius pull clamp for use in pulling vehicle door frames to straighten the same comprising first and second clamp plates which are clamped onto the door frame to assist in the straightening of the same.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   This invention relates to a radius pull clamp and more particularly to a radius pull clamp for use in pulling vehicle door frames to straighten the same. 
   2. Description of the Related Art 
   Frame racks and pulling devices are used to straighten the frames and bodies of wrecked or damaged vehicles. U.S. Pat. No. 6,098,445 illustrates a vehicle holding system used in frame straightening operations. If a door frame of the vehicle is damaged, it is extremely difficult to use the existing equipment to straighten the door frame since it is difficult to attach any type of clamp or hook to the door frames which is made even more difficult due to the fact that the door frames usually have a plurality of radiuses such as illustrated in  FIG. 1  of the patent drawings. 
   SUMMARY OF THE INVENTION 
   A radius pull clamp is described for use in pulling vehicle door frames to straighten the same. The radius pull clamp of this invention comprises first and second flat clamp plates which have inner and outer sides and a periphery. The first and second clamp plates are mirror images of one another and are adapted to be closely positioned together in a superposed relationship. Each of the clamp plates has spaced-apart bolt openings formed therein which register with the bolt openings in the other clamp plate. Bolt members extend through at least some of the registering bolt openings to hold the clamp plates closely adjacent one another. A pull bracket is secured to the pull clamp by means of a bolt member extending through registering bolt openings and through the pull bracket. Each of the clamp plates has a plurality of different radiuses formed in the periphery thereof as well as a straight peripheral portion. The inner side of the first plate has a plurality of spaced-apart teeth formed therein inwardly of the periphery thereof which extend towards the second plate. The inner side of the second clamp plate has a plurality of spaced-apart recesses formed therein inwardly of the periphery thereof which register with the teeth on the first clamp plate. 
   The pull clamp is clamped on the inwardly projecting lip of the door frame at the desired location with the pull clamp being positioned with respect thereto so that the proper radius is clamped onto the lip of the door frame. A pull chain is connected to the pull bracket and pulling force is applied to the pull clamp to straighten the door frame. The heat-treated teeth provide a non-slip hold on the door frame. 
   It is therefore a principal object of the invention to provide a radius pull clamp for use in pulling vehicle door frames to straighten the same. 
   A further object of the invention is to provide a radius pull clamp comprised of first and second flat clamp plates having a plurality of radiuses formed in the periphery thereof as well as a straight peripheral portion. 
   Yet another object of the invention is to provide a radius pull clamp of the type described including means for gripping the door frame. 
   Still another object of the invention is to provide a radius pull clamp of the type described which is easy to use. 
   These and other objects will be obvious to those skilled in the art. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of a door frame of a vehicle; 
       FIG. 2  is a perspective view of the pull clamp of this invention; 
       FIG. 3  is an exploded perspective view of the pull clamp of the invention; 
       FIG. 4  is a perspective view illustrating the radius pull clamp of this invention being clamped onto a lip of a door frame to enable the door frame to be straightened; 
       FIG. 5  is a sectional view illustrating the clamp of this invention clamped onto the lip of the door frame; and 
       FIG. 6  is a plan view of one of the pull clamp plates. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   The radius pull clamp of this invention is generally designated by the reference numeral  10  and is designed to assist in the straightening of a vehicle door frame  12  having a plurality of radiused corners or areas  14 ,  16 ,  18  and  20 , each of which normally have different radiuses. Normally, the frame  12  includes an inwardly protruding lip  20  which may be formed of one or more metal sheets positioned adjacent one another. 
   If the vehicle door frame  12  is damaged during a wreck, the door frame  12  must be straightened. However, heretofore, there has not been any convenient device for gripping any of the radiuses  14 ,  16 ,  18  and  20  to allow a pull chain of a vehicle frame straightening device or the like to pull the door frame back into proper alignment. 
   Accordingly, applicant has invented the radius pull clamp  10  to permit a pull chain to straighten a damaged door frame. Clamp  10  is comprised of flat clamp plates  22  and  24  which are mirror images of one another. Plate  22  includes an inner side  26 , an outer side  28  and a periphery  30 . Plate  24  includes an inner side  27 , an outer side  29  and a periphery  30 ′. Periphery  30  includes a plurality of radiuses formed therein. Although it is preferred that radiuses  32 ,  34 ,  36  and  38  be provided, more or less radiuses may be employed. Further, it is preferred that periphery  30  be provided with a straight peripheral portion  39 , but the same may be omitted if desired. 
   Bolt openings  40 ,  42 ,  44 ,  46  and  48  are formed in plate  22  while registering bolt openings  50 ,  52 ,  54 ,  56  and  58  are provided in plate  24 . As seen, the bolt openings formed in the plates  22  and  24  are in the approximate middle of the radiuses and the straight peripheral portion  22 . Bolts  60  are adapted to extend through at least some of the registering bolt openings and maintained therein by nuts  61 . The periphery  30 ′ of plate  24  has radiuses  32 ′,  34 ′,  36 ′,  38 ′ and straight peripheral portion  39 ′, the same being identical to the radiuses and straight peripheral portion on plate  22 . 
   The numeral  62  refers to a pull bracket including a base portion  64  and a leg portion  66  which has an opening  68  formed therein adapted to receive the hook  69  of a pull chain  70  of the frame straightening apparatus. The bracket  62  is secured to the clamp  10  by a bolt  60  extending through the registering bolt openings adjacent the radius to be secured to the lip  20 . The pull bracket  62  is secured to the clamp  10  adjacent the peripheral radius portion or straight peripheral portion being used. 
   The inner side  26  of plate  22  has a plurality of heat-treated teeth  72  extending therefrom adjacent the periphery of the clamp plate  22 , as seen in the drawings. The inner side  27  of clamp plate  24  has a plurality of recesses or pockets  74  formed therein adjacent the periphery thereof which register with the teeth  72 . When the clamp  22  is clamped onto the lip  20 , the teeth  72  grip the lip  20  and deform the lip, as seen in  FIG. 5 , so that the lip  20  is partially forced into the pocket  74 . Although the teeth  72  and pockets  74  are preferred, it is possible that the clamp plate will also function without the teeth and pockets. The plates  22  and  24  are provided with handhold openings  76  and  78 , respectively, to facilitate the handling of the radius pull clamp of this invention. In use, the pull clamp  10  is manipulated with respect to the door frame  12  to place the proper radius of the clamp  10  in the desired area of the door frame  12  which was heretofore impossible. The straight peripheral portions  39  and  39 ′ may be positioned on either side of straight portions of door frame  12  to facilitate the straightening thereof. 
   Thus it can be seen that the invention accomplishes at least all of its stated objectives.