Abstract:
A pivoting split thread chasing die with fastener is disclosed. In one example, the fastener can include a retainer that captures the fastener within one half of the thread chasing die. The thread chasing die may make it easier for a user to refurbish threads of large bolts and studs.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims priority to U.S. Provisional Patent Application No. 61/362,575, filed Jul. 8, 2010, and entitled “RELEASABLE THREAD CHASER AND NUT WITH FASTENER” the entire contents of which are hereby incorporated herein by reference for all purposes. 
     FIELD 
     The present description relates to a thread chaser for improving degraded threads of a bolt or stud. The thread chaser may be particularly useful for larger diameter bolts and studs where it can be difficult to align two faces of a releasable thread chaser. 
     BACKGROUND AND SUMMARY 
     Threads of a bolt or stud may become degraded due to wear, being struck by an object, or the environment surrounding the bolt or stud. For example, a stud used to hold a wheel of a vehicle in place may become degraded when the wheel is removed and the wheel hub skids across the threads of a stud configured to couple the wheel to a vehicle axle. In another example, threads of a threaded rod may become filled with debris from dust in the air surrounding the threaded rod. A single piece die or thread chaser may be used to refurbish threads of a bolt or stud. However, it may be difficult to start the single piece die on the threads of the bolt or stud. One way to simplify engaging a thread chaser to a bolt or stud is described in U.S. Pat. No. 6,206,620. In particular, a pivoting split thread chasing die is described. The split die allows a user to wrap the die around a bolt or stud and begin chasing threads without requiring the user to start the thread chaser at the end of the bolt or stud. Such a die allows the user to position the die at a location along the bolt or stud where the treads may be less degraded so that the operation of thread chasing can be improved. 
     The pivoting split thread chasing die described in U.S. Pat. No. 6,206,620 provides an effective tool for refurbishing threads. However, the inventors herein have determined that when a pivoting split thread chasing die is applied to larger diameter bolts or studs, the two halves of the pivoting split thread chasing die may become difficult to align. Further, when working in conditions where it may be difficult to grasp the thread chaser, the thread chaser may become more difficult to operate. 
     The inventors herein have recognized the above-mentioned disadvantages and have developed a thread chaser, comprising: a first die half; a second die half, the second die half coupled to the first die half, the first and second die halves forming a hex shaped periphery of the thread chaser when in a closed position; and a fastener that passes at least partially through the first and second die halves, the fastener including a fastener retainer, the fastener and the fastener retainer positioned within the hex shaped periphery when the thread chaser is in the closed position. 
     A pivoting split thread chasing die that includes a fastener can help to ensure that a pivoting split thread chasing die is properly aligned to a bolt or stud when chasing threads. In particular, the fastener may operate to align the halves of a pivoting split thread chasing die by acting as a locator pin between the two die halves. Further, a fastener and fastener retainer that are embedded inside of hex shaped outer periphery of the thread chaser a hex allow a user to rotate the thread chaser with a standard socket or wrench so that specialty tools may not be required to operate the thread chaser, thereby simplifying thread chaser operation. And, since the thread chaser includes a fastener retainer, the user may find the thread chaser easier to operate since the fastener can stay with the thread chaser whether the thread chaser is in an open or closed state. 
     The present description may provide several advantages. In particular, the thread chaser may improve thread chaser performance by helping to ensure thread chaser alignment while refurbishing threads of a bolt. In addition, the thread chaser fastener and retainer described herein may allow a user to adjust the clamping force of the thread chaser so as to accommodate threads of different pitch. Further, the thread chaser described herein may allow a user to operate the thread chaser without having to maintain a hold on the thread fastener while the thread chaser is being affixed to a bolt or stud. Further still, the thread chaser described herein may allow a user to retract a fastener holding portions of the thread chaser together during thread chaser removal without disengaging the fastener retainer from the fastener. 
     The above advantages and other advantages, and features of the present description will be readily apparent from the following Detailed Description when taken alone or in connection with the accompanying drawings. 
     It should be understood that the summary above is provided to introduce in simplified form a selection of concepts that are further described in the detailed description. It is not meant to identify key or essential features of the claimed subject matter, the scope of which is defined uniquely by the claims that follow the detailed description. Furthermore, the claimed subject matter is not limited to implementations that solve any disadvantages noted above or in any part of this disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The advantages described herein will be more fully understood by reading an example of an embodiment, referred to herein as the Detailed Description, when taken alone or with reference to the drawings, wherein: 
         FIG. 1  is a perspective view of an example thread chaser; 
         FIG. 2  is a plan view of the example thread chaser of  FIG. 1  shown in a partially open state; 
         FIG. 3  is a plan view of the example thread chaser of  FIG. 1  shown in a closed state; 
         FIG. 4  is a side view of the left hand side of the example thread chaser of  FIG. 1 ; 
         FIG. 5  is a side view of the right hand side of the example thread chaser of  FIG. 1 ; 
         FIG. 6  is a cut away plan view of the left hand side half die of the example thread chaser of  FIG. 1  with a thread chaser fastener removed; 
         FIG. 7  is a cut away plan view of the right hand side half die of the example thread chaser of  FIG. 1  with a thread chaser fastener removed; 
         FIG. 8  is a plan view of an example fastener for the example thread chaser of  FIG. 1 ; 
         FIG. 9  is a cut away plan view of the right hand side half die of the example thread chaser of  FIG. 1  with the thread chaser fastener installed in a first position; and 
         FIG. 10  is a cut away plan view of the right hand side half die of the example thread chaser of  FIG. 1  with the thread chaser fastener installed in a second position. 
     
    
    
     DETAILED DESCRIPTION 
     The present description is related to pivoting split thread chasing die. In one example, the thread chaser includes a fastener that acts to align two die halves and to fix a geometric relationship between the two die halves during operation of the thread chaser as shown if  FIG. 1 .  FIGS. 2-5  show different views of the thread chaser shown in  FIG. 1 . Finally,  FIGS. 6-10  show detailed views of how a fastener is retained and positioned within the pivoting split thread chasing die.  FIGS. 2-10  are shown approximately to scale. 
     Referring to  FIG. 1 , a perspective view of an example pivoting split thread chasing die  100  is shown. Left hand side die half  102  forms one half of a hex shaped die when coupled to right hand side die half  104  via hinge pin  111 . Each of left hand side die half  102  and right hand side die half  104  include threads  130 , debris clean out holes  108 , and flats  125 . A hex shaped outer periphery of the pivoting split thread chasing die  100  is formed by flats  125  when the left hand side die half  102  and the right hand side die half  104  are in a closed position. Left hand side die half  102  also includes a closing face  132  and a fastener accepting bore  115 . Similarly, right hand side die half  104  includes a closing face  134  and a fastener accepting bore  113 . In an assembled state, hinge pin  111  passes through hinge knuckle holes  109  and  107  to couple right hand side die half  104  to left hand die half  102 . Fastener  112  includes a groove  120  for retaining O-ring  122  that acts as a fastener retainer when O-ring  122  is slid over fastener  112 . 
     Cutting plane  150  defines the cross-section shown in  FIG. 6 . Cutting plane  155  defines the cross-section shown in  FIGS. 7 ,  9 , and  10 . Cutting planes  150  and  155  section left hand side die half  102  and right hand side die half  104  in half to provide details as to how fastener  112  may be positioned within pivoting split thread chasing die  100 . 
     Hinge pin  111  and hinge knuckle holes  109  and  107  allow left hand side die half  102  and right hand side die half  104  to pivot about hinge pin  111 . Since left hand side die half  102  and right hand side die half  104  are allowed to pivot about hinge pin  111 , left hand side die half  102  and right hand side die half  104  can be manipulated to open around a bolt or stud and then engage threads on the bolt or stud without starting at an end of the bolt or stud. Pivoting split thread chasing die  100  can be rotated via a socket or wrench to begin refurbishing threads of the bolt or stud after pivoting split thread chasing die  100  is coupled to a bolt or stud. Fastener  112  lies completely within the hex shaped periphery of pivoting split thread chasing die  100  when the die is in a substantially closed position. Thus, the symmetric hex shape of pivoting split thread chasing die  100  is maintained even when fastener  112  couples left hand side die half  102  and right hand side die half  104  together. 
     Referring now to  FIG. 2 , a plan view of the example thread chaser  100  of  FIG. 1  in a partially open state is shown. Left hand side die half  102  and right hand side die half  104  are shown at a slight angle with respect to each other. In one example, flats  125  are arranged at an angle of 60° between each other except for the half flats formed at the hinge end and closing face ends of left hand side die half  102  and right hand side die half  104 . Closing face  132  and closing face  134  are arranged opposite to each other so that they engage each other when pivoting split thread chasing die  100  is shown in a closed position. Threads  130  form a circular outline when left hand side die half  102  and right hand side die half  104  pivot about hinge  106  to a closed position. Debris clean out holes  108  are arranged around threads  130  to allow debris to escape from threads  130  during thread chasing. 
     Referring now to  FIG. 3 , a plan view of the example thread chaser  100  of  FIG. 1  in a closed state is shown. Left hand side die half  102  and right hand side die half  104  engage each other at closing face  132  and closing face  134 . Flats  125  form a hex shaped periphery and are the outer boundary of pivoting split thread chasing die  100  when pivoting split thread chasing die  100  is in a closed position as shown. Threads  130  and debris clean out holes  108  are arranged in a circular shape within the periphery formed by flats  125 . Centerline  302  is located at the center of the circle formed by threads  130 . Hinge  106  is within the periphery formed by flats  125  so that the hex shape is retained. 
     Flats  125  allow torque to be applied to pivoting split thread chasing die  100  so that the die may rotate in clockwise or counter clockwise directions about a bolt or stud. Further, threads  130  of left hand side die half  102  and right hand side die half  104  match at closing faces  132  and  134  when to pivoting split thread chasing die  100  is closed as shown. The features of pivoting split thread chasing die  100  allow the die to operate similar to a single piece die when the die is in a closed position. 
     Referring now to  FIG. 4 , a side view of left hand side die half  102  is shown. The side of pivoting split thread chasing die  100  includes flats  125  angled up and down with respect to the center of the die. Fastener accepting bore  115  is shown with fastener  112  positioned therein. Fastener accepting bore  115  includes threads shown in  FIG. 6  so that fastener  112  can draw left hand side die half  102  to right hand die half  104  when fastener  112  is rotated in a clockwise direction. In this way, fastener  112  passes at least partially through left hand side die half  102  and right hand side die half  104  when pivoting split thread chasing die  100  is closed and fastened together via fastener  112 . 
     Referring now to  FIG. 5 , a side view of right hand side die half  104  is shown. The side of pivoting split thread chasing die  100  includes flats  125  angled up and down with respect to the center of the die. Counter bore  502  is shown with fastener  112  positioned therein. Counter bore  502  is without threads so that fastener  112  can rotate without applying torque to right hand die half  104  when fastener  112  is rotated in a clockwise direction. 
     Referring now to  FIG. 6 , a cut away plan view of left hand die half  102  is shown. Fastener accepting bore  115  is shown traversing left hand die half  102  from closing face  132  to flat  125 . However, in other examples, fastener accepting bore  115  may begin at closing face  132  and end part way through left hand die half  102 . Fastener accepting bore  115  also includes internal threads  602  that run the entire length of fastener accepting bore  115 . Centerline  604  of fastener accepting bore  115  is arranged to align with center line  710  of fastener accepting bore  113  shown in  FIG. 7 . In this way, left hand die half  102  can be aligned with right hand die half  104  when fastener  112  is positioned within the two die halves. Fastener accepting bore  115  does not communicate with threads  130  or debris clean out holes  108  whether or not fastener  112  is positioned therein. 
     Referring now to  FIG. 7 , a cut away plan view of right hand die half  104  is shown with fastener  112  removed. Fastener accepting bore  113  is shown traversing a portion of left hand die half  104  from closing face  134  to counter bore  502 . Counter bore  502  extends from fastener accepting bore  113  to flat  125 . Neither fastener accepting bore  113  nor counter bore  502  are threaded. Centerline  710  is a centerline common to both fastener accepting bore  113  and counter bore  502 . Fastener accepting bore  113  and counter bore  502  do not communicate with threads  130  or debris clean out holes  108  whether or not fastener  112  is positioned therein. Dimension  702  shows the depth or length of fastener accepting bore  113  while dimension  704  shows the depth or length of counter bore  502 . Shoulder  706  is formed where fastener accepting bore  113  and counter bore  502  meet. Thus, counter bore  502  has a larger diameter than fastener accepting bore  113 . 
     The length or depth  704  is of counter bore  502  is selected so that fastener  112  is within the periphery of pivoting split thread chasing die  100  when the die is substantially closed. In one example, the length or depth of counter bore  502  is selected to be longer than a height of a head of fastener  112 . Further, the diameter of counter bore  502  is selected to be greater than a diameter of a head of fastener  112 . If some space is allowed between a head of fastener  112  and a wall of counter bore  502 , fastener  112  may engage left hand die half  102  at greater distances since fastener  112  may be adjusted to an angle relative to centerline  710  of right hand die half  104 . However, if a large amount of space is allowed between a head of fastener  112  and a wall of counter bore  502 , alignment of left hand die half  102  and right hand die half  104  may degrade. 
     The length or depth  702  is of fastener accepting  113  bore is selected so that fastener  112  can be withdrawn to where an end of fastener  112  is flush with closing face  134  or recessed within right hand die half  104  while still being retained via a fastener retainer that is in communication with fastener accepting bore  113 . The diameter of fastener accepting bore  113  is selected to be greater than a diameter of threads of fastener  112 . If some space is allowed between threads of fastener  112  and a wall of fastener accepting bore  113 , fastener  112  may engage left hand die half  102  at greater distances since fastener  112  may be adjusted to an angle relative to centerline  710  of right hand die half  104 . However, if a large amount of space is allowed between threads of fastener  112  and a wall of fastener accepting bore  113 , alignment of left hand die half  102  and right hand die half  104  may degrade. In one example, the diameter of fastener accepting bore  113  is selected to provide a capture fit between O-ring  122 , fastener  112 , and fastener accepting bore  113 . For example, a diameter of fastener accepting bore  113  may be in a range of 0.001-0.150 of an inch smaller than a diameter of O-ring  122  when O-ring  122  is placed in groove  120  of fastener  112  depending on the size of the left hand die half  102  and right hand die half  104 . In this way, the O-ring  122  and fastener accepting bore  113  operate as a retainer for fastener  112 . In particular, O-ring  122  may be compressed against fastener  112  by fastener accepting bore  113  to limit motion of fastener  112  within fastener accepting bore  113 . 
     Of course, the distances and dimension shown in  FIG. 7  can vary for different size thread chasers. Accordingly, the figures shown are not intended to limit the scope or breadth of the disclosure. 
     Referring now to  FIG. 8 , a plan view of an example fastener for the example thread chaser of  FIG. 1  is shown. Fastener  112  includes a head  802 , shank  806 , end  804 , retainer groove  120 , and external threads  808 . The overall length  824  of fastener  112  is selected such that fastener  112  is within the periphery of the hex formed by flats  125  shown in  FIG. 1  when pivoting split thread chasing die  100  is substantially closed. Thus, the overall length  824  is less than a distance between two flats of pivoting split thread chasing die  100  when the die is substantially closed. 
     Groove  120  is positioned such that when an O-ring  122  is placed in groove  120 , the O-ring  122  is within fastener accepting bore as shown in  FIGS. 9 and 10 . For example, the distance  822  from the head  802  to the end of the groove  120  may be the length  702  of fastener accepting bore  113  shown in  FIG. 7 . In this way, O-ring  122  may remain within right hand die half  104  when fastener  112  is fully tightened and head  802  engages shoulder  706  shown in  FIG. 7 . On the other hand, when end  804  is flush or within thread accepting bore  113 , O-ring groove is also still within thread accepting bore  113 . In this way, groove  120  can be positioned along fastener  112  so that fastener  112  is retained within thread accepting bore  113  when fastener  112  is engaged with threads  602  of left hand die half  102  and fully tightened as well as when end  804  of fastener  112  is retracted from closing face  134  of right hand die half  104 . 
     The length  820  of threads  808  can be selected based on how far away it is desirable for fastener  112  to engage threads  602  of left hand die half  102  when fastener  112  is positioned within fastener accepting bore  113 . However, it may be desirable for the overall length  824  of fastener  112  to be less than a distance between two flats of pivoting split thread chasing die  100  when the die is closed. 
     The diameter  812  of head  802  is selected to be smaller than the diameter of counter bore  502  shown in  FIG. 7 . Thus, when fastener  112  is installed in right hand die half  104  and coupled with left hand die half  102 , fastener is within the bounds of thread chaser  100  so that a socket can fit over thread chaser  100 . In this way, fastener  112  does not interfere with the rotation or operation of thread chaser  100 . 
     Referring now to  FIG. 9 , a cut away plan view of the right hand side half die of the example thread chaser of  FIG. 1  is shown. Fastener  112  is shown in a fully extended position where end  804  is at its most extended position from closing face  134  when fastener  112  is within fastener accepting bore  113 . When fastener head  802  engages shoulder  706 , O-ring  122  and groove  120  are flush with closing face  134 . Alternatively, O-ring  122  and groove  120  can be positioned within fastener accepting bore  113  when fastener head  802  engages shoulder  706 . Head  802  of fastener  112  is also within counter bore  502  when in the fully extended position. Fastener  112  may be in the fully extended position when fastener is coupled to threads  602  of left hand die half  102 . In this way, fastener  112  may not interfere with rotation of the die when the die is in a closed position. Fastener  112  may reach the fully extended position by rotating fastener  112  when fastener  112  is engage with threads  602  shown in  FIG. 6 . In some examples, O-ring fastener  122  rotates as fastener  112  rotates. Further, O-ring fastener retainer  122  may slide along the length of fastener accepting bore  113  when fastener  112  is rotated and the left hand die half  102  and when the right hand die half  104  are drawn together via rotating fastener  112 . 
     Threads  130  and debris clean out holds  108  are shown not in communication with fastener  112  and fastener accepting bore  113 . Counter bore  502  passes though one flat  125  while fastener accepting bore  113  passes through closing face  134 . It should also be noted that in some examples the O-ring  122  or another style fastener retainer may be retained in the fastener accepting bore  113  or counter bore  502  rather than by fastener  112 . For example, a gasket including a rubber seal may be pressed into counter bore  502  or fastener accepting bore  113  to retain fastener  112 . In one example, the rubber seal may be similar to a wheel axle seal of a vehicle. Thus, a variety of other retainers held in place via fastener  112  or the die body are anticipated. 
     Referring now to  FIG. 10 , a cut away plan view of the right hand side die half with a retracted die fastener is shown.  FIG. 10  is identical to  FIG. 9  except that fastener  112  is shown partially retracted. 
     Fastener  112  is shown in a partially retracted position where end  804  is at a position where closing face  134  can engage closing face  132  as shown in  FIG. 2  without interference from fastener  112  engaging closing face  132  before closing face  134  engages closing face  132 . Fastener head  802  is clear of shoulder  706  when the end  804  of fastener  112  is flush with closing face  134 . Further, end  804  can be inside of fastener accepting bore  113  while O-ring  122  is within fastener accepting bore. In this way, fastener  112  may not interfere with closing face  132  during closing of both ends of pivoting split thread chasing die  100 . Further, O-ring  112  slides along the length of fastener accepting bore  113  where fastener  112  is tightened. 
     Thus,  FIGS. 1-10  provide for a thread chaser, comprising: a first die half; a second die half, the second die half coupled to the first die half, the first and second die halves forming a hex shaped periphery of the thread chaser when in a closed position; and a fastener that passes at least partially through the first and second die halves, the fastener including a fastener retainer, the fastener and the fastener retainer positioned within the hex shaped periphery when the thread chaser is in the closed position. In this way, two sides of a split thread chaser may be aligned while rotation of the thread chaser is not affected. 
     In one example, the thread chaser of further comprises a hinge, the hinge coupling the first die half to the second die half, the hinge positioned on a side of the second die half opposite a side of the second die half where the fastener is positioned. The thread also further comprises a plurality of debris clean out holes traversing the first and second die halves, the fastener not in communication with the plurality of debris clean out holes. In one example, the thread chaser includes where the hex shaped periphery is a boundary formed by a plurality of flats of the first die half and the second die half when the fastener draws a first closing face of the first die half to a first closing face of the second die half. The thread also includes where the fastener retainer is comprised of an O-ring. The thread also includes where the fastener includes a fastener retainer groove, and where the O-ring is captured by the groove. In another example, the thread chaser includes where the fastener retainer is a positioned between the fastener and a bore in the second die half, and where the retainer operates to retain the fastener only when the fastener retainer is within the bore in the second die half. 
     The thread chaser illustrated in  FIGS. 1-10  also comprises: a first die half including a first fastener accepting bore and internal threads; a second die half including a second fastener accepting bore and a counter bore, the second fastener accepting bore and the counter bore having a common centerline; a hinge pin coupling the first die half and the second die half; and a fastener including external threads fit to the internal threads and a sliding fastener retainer, the fastener coupling the first die haft to the second die half. The thread chaser also includes where the fastener includes a fastener retainer groove. Thus, the fastener may be comprised of several components. 
     The thread chaser also includes where the second fastener accepting bore extends from a closing face of the second die half to the counter bore, and where the counter bore extends from the second fastener accepting bore to a flat of the second die half. In one example, the thread chaser includes where the groove is positioned on the fastener such that the fastener is captured within the second die half when an end of the fastener is flush with the closing face of the second die half. The thread chaser also includes where the groove is positioned such that the fastener retainer is flush with the closing face of the second die half when the closing face of the second die engages a closing face of the first die, or where the groove is positioned such that the fastener retainer is within the bore. 
     In some examples, the components of the thread chaser may be adjusted for the size of the threads being chased. For example, the thread chaser includes where a depth of the counter bore from the flat is at least a length greater than a height of a head of the fastener. In addition, the thread chaser includes where a shoulder formed by the counter bore and the second fastener accepting bore is positioned such that a head of the fastener is in communication with the shoulder when the closing face of the first die engages a closing face of the second die. Further, the thread chaser includes where the fastener retainer is arranged to slide within the second fastener accepting bore. 
     A thread chaser, comprising: a first die half including a first fastener accepting bore and internal threads; a second die half including a second fastener accepting bore and a counter bore, the second fastener accepting bore and the counter bore having a common centerline; a hinge pin coupling the first die half and the second die half; and a fastener including external threads fit to the internal threads and a fastener retainer, the fastener positioned at least partially within the second die half, the fastener retainer compressed between the fastener retainer and the second fastener accepting bore. The thread chaser also includes where the fastener retainer is a synthetic rubber O-ring, and where the O-ring is captured in a groove of the fastener. The thread chaser also includes where a head of the fastener engages a shoulder of the second die half. In one example, the thread chaser includes where the fastener passes through a closing face of the second die half. The thread chaser also includes where the fastener includes an unthreaded shank between the groove and the head of the fastener. 
     This concludes the description. The reading of it by those skilled in the art would bring to mind many alterations and modifications without departing from the spirit and the scope of the description. It will be appreciated that the configurations and/or approaches described herein are exemplary in nature, and that these specific examples or examples are not to be considered in a limiting sense, because numerous variations are possible. The subject matter of the present disclosure includes all novel and nonobvious combinations and subcombinations of the various features, functions, acts, and/or properties disclosed herein, as well as any and all equivalents thereof.