Abstract:
A thread chaser device is provided for clearing, cleaning, and repairing damaged, dirty, or otherwise impaired threads on a threaded object, such as a bolt or other like objects. In a preferred embodiment, the thread chaser comprises half a die welded into both jaws of a wrench. Alternatively, the thread chaser may include removable die-blocks containing multiple half dies for use with bolts or threaded objects of various sizes and diameters. The thread chaser may optionally include a means for locking the jaws in a closed position around the threaded object.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. provisional application No. 61/423,133 filed Dec. 15, 2010. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates generally to a thread chaser for cleaning out and repairing damaged threads of a bolt or pipe, and in particular a device suitable for cleaning or repairing threads in obstructed areas whether the threads are right-handed or left-handed. 
         [0004]    2. Description of the Related Art 
         [0005]    A wide variety of devices are available for cutting and chasing threads of bolts and other like objects. The most common of these devices comprises a die that is gripped by a turning tool such as a conventional wrench, die stock, die handle or the like. The die is placed over the damaged thread and rotated by a turning tool to clean and repair the thread. Due to the size of many thread chasers and/or the radius of their turning device, damaged threads must be removed from operation in order to be repaired. 
         [0006]    Heretofore there has not been available a thread chaser with the advantages and features of the present invention. 
       SUMMARY OF THE INVENTION 
       [0007]    In the practice of the present invention a thread chaser device is provided. Without limitation, the thread chaser is adapted for cleaning and repairing damaged threads on bolts or other like objects. In a preferred embodiment, the thread chaser comprises half a die welded into both jaws of a wrench. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The drawings constitute a part of this specification and include exemplary embodiments of the present invention illustrating various objects and features thereof. 
           [0009]      FIG. 1  is an upper, front isometric view of a pliers thread chaser device comprising an embodiment of the present invention in an open position. 
           [0010]      FIG. 2  is an upper, front isometric view of the pliers thread chaser in a closed position. 
           [0011]      FIG. 3A  is a cross-sectional view of the thread chaser engaged with a damaged thread. 
           [0012]      FIG. 3B  is a cross-sectional view of the thread chaser engaged with and repairing the damaged thread. 
           [0013]      FIG. 3C  is a cross-sectional view of the repaired thread and the thread chaser. 
           [0014]      FIG. 4  is a side elevation of an adjustable-diameter thread chaser comprising an alternative embodiment of the present invention. 
           [0015]      FIG. 5  is a side elevation of a multi-diameter thread chaser device in the jaws of a pair of locking pliers comprising an alternative embodiment of the present invention. 
           [0016]      FIG. 6  is a side elevation of a multi-diameter thread chaser jaw removed from the locking pliers to show a rack and pinion mechanism comprising an alternative embodiment of the present invention. 
           [0017]      FIG. 7  is a side elevation of a multi-diameter thread chaser jaw removed from the locking pliers to show the rack and pinion mechanism. 
           [0018]      FIG. 8  is a top plan view of the multi-diameter thread chaser jaw. 
           [0019]      FIG. 9  is a side elevation of a locking pliers thread chaser comprising an alternative embodiment of the present invention, shown with the jaws closed. 
           [0020]      FIG. 10  is a side elevation of the locking pliers thread chaser, shown with the jaws open. 
           [0021]      FIG. 11  is an enlarged, fragmentary view of the thread chaser taken generally within Circle  11  in  FIG. 10  and showing a removable die. 
           [0022]      FIG. 12  is an enlarged, cross-sectional view taken generally along line  12  in  FIG. 11 . 
           [0023]      FIG. 13  is a side elevation of locking pliers comprising an alternative embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     I. Introduction and Environment 
       [0024]    As required, detailed aspects of the present invention 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. 
         [0025]    Certain terminology will be used in the following description for convenience in reference only and will not be limiting. For example, up, down, front, back, right and left refer to the invention as orientated in the view being referred to. The words, “inwardly” and “outwardly” refer to directions toward and away from, respectively, the geometric center of the aspect being described and designated parts thereof. Forwardly and rearwardly are generally in reference to the direction of travel, if appropriate. Said terminology will include the words specifically mentioned, derivatives thereof and words of similar meaning. 
       II. Preferred Embodiment or Aspect of the Thread Chaser  2   
       [0026]    Referring to the drawings in more detail, the reference numeral  2  generally designates a thread chaser embodying an aspect of the present invention. Without limitation on the useful applications of the thread chaser  2  comprising the present invention, an exemplary pliers thread chaser includes upper and lower handles  4 ,  6 ; a connection hinge  8 ; upper and lower jaws  16 ,  10 ; and upper and lower dies  14 ,  12 . The improved features of the present invention over the prior art include the elimination of the need to remove the damaged thread for repair, the ability to use the present invention on either right or left hand threads, and the ability to use the present invention in tight or otherwise obstructed spaces. It should be noted that the present invention is not, however, limited to any or all of these features, or to the disclosed application. 
         [0027]    The handles  4 ,  6  have gripping surfaces  36 . The connection hinge  8  holds the thread chaser  2  together and is the pivot point about which the thread chaser  2  opens and closes. The dies  12 ,  14  can be welded or otherwise suitably fastened onto the jaws  10 ,  16 . The dies  12 ,  14  include female threads  32  and debris channels  34 . 
       III. Operation 
       [0028]    The thread chaser  2  can be opened by pulling the handles  4 ,  6  apart to separate the dies  12 ,  14  as seen in  FIG. 1 . The thread chaser  2  can be closed by pulling the handles  4 ,  6  together as seen in  FIG. 2 .  FIG. 3A  is a cross-sectional view of the lower die  12  and lower jaw portion of the thread chaser  2  when it is in a closed position and engaged with a thread  20  having a damaged end  18 . The lands  22  and grooves  24  of the thread  20  fit into the lands  26  and grooves  28  of the thread chaser  2 . With the handles  4 ,  6  held together to keep the dies  12 ,  14  clamped onto the threads  20 , the thread chaser  2  is then rotated.  FIG. 3B  shows the thread chaser  2  moving up the thread  20  as it is rotated and beginning to repair the damaged portion  18 . As the thread chaser  2  repairs and cleans the damaged portion  18  of the thread  20 , the pieces of the thread  20  that are removed fall out of the debris channels  34 .  FIG. 3C  shows the thread  20  with a repaired end  26 . 
       IV. Alternative Embodiment or Aspect of the Thread Chaser  102   
       [0029]      FIG. 4  shows an adjustable wrench thread chaser  102  comprising upper and lower hingedly connected handles  104 ,  106 ; upper and lower jaws  116 ,  110 ; and upper and lower dies  114 ,  112 . The upper and lower adjustable dies  114 ,  112  can be rotated about pivot pins  118  to change the diameter of the thread chaser  102  in order to repair different sizes of bolts, rods and other threaded objects. Threaded seats are included for use with threaded objects of multiple sizes and/or shapes. 
         [0030]    The thread chaser  102  operates in a similar manner to the wrench thread chaser  2  by pulling the handles  104 ,  106  together to clamp the dies  112 ,  114  around a thread. The thread chaser  102  is then rotated around the thread while the handles  104 ,  106  are held together. 
       V. Alternative Embodiment or Aspect of the Thread Chaser  202   
       [0031]      FIG. 5  shows a thread chaser  202  comprising upper and lower handles  204 ,  206 ; pivot pins  208 ; upper and lower jaws  216 ,  210 ; upper and lower die blocks  214 ,  212 ; a jaw traverse slot  218 ; a retracting spring mounting hole  220 ; and a retracting spring  222 . The die blocks  214 ,  212  house several different size dies to allow for the repair of multiple sizes of threads.  FIGS. 6 and 7  show a rack  228  and a pinion  226 . The rack  228  is connected to the lower die block  212  and the lower jaw  210 . When the lower handle  206  is squeezed, the rack  228  and the pinion  226  move the lower jaw  210  and the lower die block  212  upwardly towards the upper die block  214  and the upper jaw  214 . 
         [0032]    The parallel pliers thread chaser  202  operates in a similar manner to the previous embodiments. The lower handle  206  is squeezed towards the upper handle  204 , which clamps the adjustable dies  112 ,  114  around a thread. The handles  206 ,  204  are locked by turning the locking nut  224  and the thread chaser  202  is then rotated around the thread. 
       VI. Alternative Embodiment or Aspect of the Thread Chaser  302   
       [0033]      FIG. 9  shows a locking pliers thread chaser  302  in the closed position. The thread chaser  302  comprises an upper handle  304 ; a lock grip  306 ; a release grip  318 ; pivot pins  308 ; upper and lower jaws  316 ,  310 ; upper and lower die blocks  314 ,  312 ; a retracting spring mounting hole  320 ; a retracting spring  322 ; a locking nut  324 ; and a knob  326 . The die blocks  314 ,  312  house several different sizes of dies to allow for the repair of multiple sizes of threads. 
         [0034]    The thread chaser  302  can be clamped around a thread by squeezing the lock grip  306  and locking the lock nut  324 . The thread chaser  302  is then rotated around the thread to repair it. After the thread has been repaired, the thread chaser  302  can be released from the thread by unlocking the lock nut and squeezing the release grip  318  to separate the die blocks  312 ,  314  as seen in  FIG. 10 . The release grip  318  can engage the knob  326  which prevents a violent movement of the lock grip  306  when released under extreme pressure. 
         [0035]    As shown in  FIGS. 11-12 , the jaws  310 ,  316  can removably mount the dies  312 ,  314 . The jaws  310 ,  316  can include V-shaped grooves  332 , which slidably receive respective rails  334  formed in the jaws  310 ,  316 . The dies  312 ,  314  are releasably retained on the jaws  310 ,  316  by ball detent fasteners comprising balls  338  biased by compression springs  336  into detents  340 . 
       VI. Alternative Embodiment or Aspect of the Locking pliers  402   
       [0036]      FIG. 13  shows a pair of locking pliers  402  similar to the thread chaser  302  described above but with teeth  412 ,  414  instead of die blocks. The locking pliers  402  operate in the same way by squeezing the lock grip  406  to clamp the teeth  412 ,  414  together and squeezing the release grip  418  to unclamp the teeth  412 ,  414 . 
         [0037]    It is to be understood that while certain aspects of the invention have been shown and described, the invention is not limited thereto and encompasses various other embodiments and aspects. For example, the thread chasers can accommodate various standard thread configurations, such as SAE, metric, coarse thread (CT), tapered, etc.