Abstract:
A pliers tool for removal of push pins used to join mechanical parts includes opposed jaw elements having a wedge configuration and a cylindrical passage in the tip of the wedge sections that prevents breaking of the shaft of a push pin during removal.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]     This is a utility application based upon, claiming priority to and incorporating by reference provisional application Ser. No. 60/642,821, filed Jan. 11, 2005.  
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     In a principal aspect the present invention relates to a pliers type tool which is designed for use in the removal of push pins of types commonly employed in the manufacture of motor vehicles.  
         [0003]     Molded polymeric push pins are utilized for multiple purposes in the assembly of motor vehicles. These push pins have a variety of configurations and constructions. For example, such push pins may employ a head mounted on a shaft wherein the shaft includes various flutes, barbs or projections for retaining the push pin within an opening through a frame or body member. Another construction for a push pin utilized in vehicle assembly comprises a two-part push pin assembly. A two-part push pin assembly employs an annular housing and a separate pin having a center shaft and head member. The shaft is fitted into the annular housing in order to lock the push pin and housing into position in an opening in a motor vehicle body or the like. Various other types of push pins are also utilized and variations in the construction of push pins of the types generally described are available. That is, the head and shaft constructions of two-part push pins may be varied. The annular housing may be varied. The dimensions, shaft configuration and head configuration may be varied.  
         [0004]     Push pins of the type described are used, for example, to retain bumper housings, body panels, and other components of a motor vehicle attached to a body or frame member. Such push pins may also be used in other environments for other types of assembly such as for appliances, motor homes, toys and the like.  
         [0005]     When repairing a motor vehicle or replacing parts of the vehicle, or when repairing other items which are assembled or retained in position by means of push pins, it is often necessary to remove the pins to dismantle parts for access to the underlying frame or substructure. Removal of such pins is preferably effected with a minimum amount of damage to the pin, as well as to the component part held in place by the pin. To effect such removal, various types of plier constructions and other tools have been proposed and/or utilized. Nonetheless, there has remained the need for a tool which provides adequate mechanical advantage to effect removal of pin while at the same time having a broad applicability, that is, to be useful for the removal of multiple types and shapes of push pins. These, among other features have inspired development of the present invention.  
       SUMMARY OF THE INVENTION  
       [0006]     Briefly, the present invention comprises a pliers configured tool made from first and second substantially identical plier elements. Each of the elements includes an elongate handle section or manual handle that extends along a generally straight, elongate axis. The elongate handle axis handle section is integrally connected with a run that forms an angle therewith in the range of about 40-50° with the axis. The connecting run includes a midpoint with an opening therethrough and a recessed section extending generally along the length of the connecting run. A jaw extension is integrally connected to and extends from the connecting run in a direction generally parallel to the elongate handle axis. The jaw extension further includes a gripping jaw member which extends generally transversely toward the elongate handle axis and which terminates with a wedge shaped member or section. The wedge shaped member or section is defined by an outer curved face and a generally flat, inclined plane, inner face. Further, the center of the end of the wedge shaped member or section includes a semi-cylindrical passage through the center thereof, or through the tip of the jaw member. The passage has an axis of rotation generally parallel to the elongate straight handle axis and midway between the spaced straight handle axes of the assembled tool.  
         [0007]     That is, two of the pliers elements are assembled by being overlayed, one with respect to the other and retained together by means of a pivot pin or bolt and locking nut so that the assembly will have the general configuration of a pliers that can be used to engage the head of a push pin and effectively remove the push pin from a retention opening. The semi-cylindrical passage through the tip of the jaw is designed so that the jaw tip may fit around and under the head of a push pin without cutting the shaft of the push pin while enabling the tool to tightly grip the push pin and effect removal from the article in which the push pin is placed. Single and two-part push pins may be effectively removed using the tool. The inclined plane or wedge surface of the push pin may be used to fit or be slipped under the head of a two-part push pin assembly or into a slot associated with a construction of a two-part push pin assembly to wedge the center headed push pin from the annular housing or element. The pliers construction of the invention thus has applicability for removal of multiple types of push pins without damaging the push pin and, in particular, without removing the head from the shaft of the push pin.  
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0008]     In the detailed description which follows, reference will be made to the drawing comprised of the following figures:  
         [0009]      FIG. 1  is a side view of the tool of the invention;  
         [0010]      FIG. 2  is a top plan view of the tool of  FIG. 1 ;  
         [0011]      FIG. 3  is a left hand end view of the tool of  FIG. 1 ;  
         [0012]      FIG. 4  is a right hand end view of the tool of  FIG. 1 ;  
         [0013]      FIG. 5  is a side elevation of one of the plier elements of the tool of  FIG. 1 ;  
         [0014]      FIG. 6  is a top plan view of the element of  FIG. 5 ;  
         [0015]      FIG. 7  is an enlarged side view of the jaw construction of the tool of  FIG. 5 ;  
         [0016]      FIG. 8  is an exploded isometric view of the tool of  FIG. 1 ;  
         [0017]      FIG. 9  is a section view wherein the tool of the invention is used with a headed fastener of a two-part push pin;  
         [0018]      FIG. 10  is a sectional view wherein the tool of the invention is utilized with a push pin having a single head and single shaft;  
         [0019]      FIG. 11  is an isometric view depicting the utilization of the tool of the invention with a two-part push pin wherein the head of the push pin center section is recessed within a slot in the annular member of the push pin assembly; and  
         [0020]      FIG. 12  is an isometric view of the manner of use of the tool of the invention with respect to a push pin of the type depicted in  FIG. 11 .  
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0021]     Referring to the figures, the tool of the invention comprises and generally has the configuration of a pliers or type tool. The pliers type tool is comprised of first and second substantially identical pliers subparts or elements  20 ,  22 . Thus, a description of one of the pliers elements utilized in the tool applies to the other element. Referring to the figures, the pliers element  20  includes an elongate longitudinal straight line axis  24  associated with a generally elongate straight handle section  26 . In practice, the handle section  26  is covered by a vinyl or coated plastic grip  27  to facilitate comfort during use of the tool.  
         [0022]     The elongate handle section  26  is a generally straight section integrally connected to intermediate run  30  that extends at an angle  32  in the range of 40-50° with respect to handle section  26 . The angle  32  is defined by the angle between the axis  24  and the elongate integral connecting run  30 . That is, referring to the figures, an angle  32  is defined between the connecting run  30  and the axis  24 . The connecting run  30  is a generally straight line element and includes a midpoint or center passage or opening  36  and further includes a recessed section  38  relative to handle section  26  which extends substantially from the elongate handle  26  to the initial portion of a jaw  40 . The recessed section  38  is provided so that the two pliers elements  20  and  22  may be matched or faced one against the other and provide thereby a configuration having a uniform width  39  as depicted, for example, in  FIG. 2 . The thickness of each section  38  is thus one half (½) of the width  39  of the combined elements  20 ,  22 . Typically, the handle sections  26  have a uniform width  39 .  
         [0023]     The jaw or jaw extension  40  extends along an axis  42  which is generally parallel to the axis  24  and spaced a distance therefrom determined by or defined by the integral connecting run  30 . The jaw extension  40  further includes an upwardly or inwardly extending gripping jaw member  44  which extends generally along an axis  43  transverse or normal to the axis  42  and which is defined by an arcuate or a curved outer face  46  and an inner face  48 . The inner face  48  connects with an inclined, generally flat face  50  that extends outwardly and intersects the curved outer face  46 . In this manner, a wedge configuration  47  is formed. The configuration or wedge  47  that is formed includes, at its distal or outer end, a generally semi-cylindrical passage or opening  60  having an axis of rotation  62  which is generally parallel to the axes  24  and  42 . In this manner, there is defined on each side of the opening or passage  60  a sharp inclined wedge section  66  and  68  spaced one from the other by the opening or passage  60 . When so assembled, the elements  20 ,  22  include axes that have various preferred relationships. Thus, axis  24  of element  20  is generally coincident with axis  42  of element  22 . Axis  24  of element  20  is generally coincident with axis  42  of element  22 . Axis  62  is midway between and parallel to axes  42  of elements  20 ,  22 . Axis  62  intersects axis  73  at a right angle. Axis  62  intersects axis  43  of a right angle. The handle axes  42 , jaw extension axes  42 , jaw axis  43  and passage axis  62  are all generally coplanar.  
         [0024]     The pliers elements  20  and  22  are retained, notably connected to each other by means of a bolt  70  and a nut  72  which wherein the bolt includes a shaft  71  with axis  73  fitted through the openings  36  of the respective elements  20  and  22 . Axis  73  is normal to axis  62 .  
         [0025]     The figures beginning with  FIGS. 9-12  illustrate in detail how the tool of the invention may be utilized to remove various types of push pins. That is, one type of push pin, for example, as depicted in  FIG. 9 , includes a head  80  and a shaft  82  with projecting barbs or flanges  84  mounted in an annular tube or housing  86 . The tool of the invention is designed so that the wedge shaped sections  47  will fit under the head  80  but not cut the shaft  82  of the push pin and may be then clamped against the push pin so that the push pin may be pulled and removed. The annular tube  86  may then be gripped by the wedge sections  47  and pulled from the opening  90  in the sheets  92 ,  93 . Again, because of the semi-cylindrical passages  60 , the tool avoids cutting or breaking the tube  86  during removal.  
         [0026]      FIG. 10  illustrates removal of a push pin  96  from sheets or joined members  97 ,  98  using the tool. Flutes of the pin  96  are effectively pulled through the mated opening of the joined members  97 ,  98  without removing or cutting the shaft of the pin  96 .  
         [0027]      FIGS. 11 and 12  also depict how the tool of the invention might be utilized in combination with a two-part push pin construction as shown in  FIG. 9 . Note that the wedge sections  47  and/or  47  may be used when the push pin head  99  is recessed in a slot  100  by gripping the push pin head  99  to initiate removal. This is accomplished by canting the tool slightly as depicted in  FIG. 11 . After the push pin head is partially removed from such a push pin construction, the pliers tool may be reoriented so that the openings or passages  60  are aligned with the shaft of the push pin  96  to complete the removal from an annular housing associated with the push pin assembly.  
         [0028]     The tool construction of the invention is designed for comfort as well as aesthetics. The arrangement of the axes and the utilization of various design elements for the tool provide an aesthetic and pleasingly appearing tool while at the same time providing a tool which is highly efficient, compact, rugged and easy to use.  
         [0029]     While there has been set forth a preferred embodiment of the invention, it is to be understood that the invention is limited only by the following claim and equivalents thereof.