Abstract:
A two-section tool joint comprises a first rod, an engaging element, a second rod and a limiting element. The two-section tool joint utilizes an elastic engaging structure to obtain an engaging effect during a multi-angle screwing/unscrewing operation, meanwhile, the tool joint can be fixed stably, avoiding the retraction of the tool joint and reducing the difficultly and inconvenience of the screwing/unscrewing operation.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a tool joint; and more particularly to a two-section tool joint. 
         [0003]    2. Description of the Prior Art 
         [0004]    In order to make tools applicable to various locking elements and have various working angles, the tools can be equipped with a tool joint. 
         [0005]    Referring to  FIG. 1 , a first conventional tool joint disclosed in Taiwan Patent No. 097208543 essentially comprises a first rod  11  and a second rod  12 . A polygonal ball  111  of the first rod  11  is restricted in a receiving groove  121 , so that the first rod  11  can be adjusted to a predetermined angle with respect to the second rod  12 . Between the receiving groove  121  and the polygonal ball  111  is disposed an elastic element  13  for elastically pressing against the polygonal ball  111  to maintain the first rod  11  and the second rod  12  at the predetermined angle after adjustment. However, the angle between the above first and second rods  11 ,  12  may change at any moment when the above tool joint is used in a screwing/unscrewing operation requiring no angular adjustment, thus causing much inconvenience and difficulty. 
         [0006]    Referring to  FIG. 2 , a second conventional tool joint disclosed in Taiwan Patent No. 097207779 comprises a first rod  21  and a second rod  22  which are fixedly connected together by inserting a fixed end  211  of the first rod  21  into an inner groove  221  of the second rod  22 . Therefore, the second conventional tool joint is applicable to the screwing/unscrewing operation which requires no angular adjustment. When the second conventional tool joint is used in a screwing/unscrewing operation requiring angular adjustment, the first rod  21  will be pulled to make the fixed end  211  of the first rod  21  disengage from the inner groove  221  of the second rod  22 , so that the first rod  21  can be adjusted to a predetermined angle with respect to the second rod  22 . However, after the first rod  21  is pulled toward an opening of the receiving groove  222  of the second rod  22 , since there is no corresponding fixing structure, the first rod  21  will retract when the above conventional tool joint is used in the screwing/unscrewing operation requiring angular adjustment, thus causing much difficulty and inconvenience. 
         [0007]    Referring to  FIG. 3 , a third conventional tool joint disclosed in Taiwan Patent No. 097203831 utilizes an annular protrusion  311  of a rod  31  to abut against an annular flange  321  of a holding seat  32  to fixedly connect the rod  31  and the holding seat  32  together, so that it can be applied in the screwing/unscrewing operation requiring no angular adjustment. When the rod  31  and the holding seat  32  are used in the screwing/unscrewing operation requiring angular adjustment, the rod  31  can be rotated relative to the holding seat  32  within a predetermined range after being pulled up slightly from the holding seat  32 . However, the connecting end  312  of the rod  31  is restricted in the groove  322  of the holding seat  32  by means of an elastic element  33  cooperating with an engaging element  34 . The working direction of the elastic element  33  and the engaging element  34  is different from the pulling direction of the rod  31  in the holding seat  32 , namely, one is longitudinal, and the other is transverse. Therefore, after the rod  31  is pulled toward an opening of the groove  322  of the holding seat  32 , the rod  31  will retract, thus causing much difficulty and inconvenience in the screwing/unscrewing operation requiring angular adjustment. 
         [0008]    The present invention has arisen to mitigate and/or obviate the afore-described disadvantages. 
       SUMMARY OF THE INVENTION 
       [0009]    The primary objective of the present invention is to provide a two-section tool joint which utilizes an elastic engaging structure to obtain an engaging effect and be fixed stably during a multi-angle screwing/unscrewing operation, avoiding the retraction of the tool joint and reducing the difficulty and the inconvenience of the screwing/unscrewing operation. 
         [0010]    Hence, in order to achieve the above objective, a two-section tool joint in accordance with the present invention comprises a first rod, an engaging element, a second rod and a limiting element. The first rod includes a receiving groove in one end thereof, on an inner surface of the receiving groove are equidistantly provided six engaging protrusions, between each two neighboring engaging protrusions is defined an engaging groove. The engaging element includes a bottom and six support arms that are equidistantly arranged around a circumference of the bottom, each of the six support arms includes a first inwards-bent engaging portion and a second outwards-bent engaging portion connected to the first engaging portion, the first and the second engaging portions are allowed to restore to their original shapes after being deformed under pressure. The engaging element is disposed in the receiving groove of the first rod, and the bottom of the engaging element abuts against a bottom surface of the receiving groove. The support arms are located in the respective engaging grooves. The second rod includes a driving portion and a hexagonal ball along an axis thereof, the hexagonal ball includes six upper abutting surfaces and six lower abutting surfaces that are arranged around the axis, the respective lower abutting surfaces are located farther from the driving portion than the upper abutting surface, and the hexagonal ball is movably assembled in the receiving groove of the first rod. When the second rod is pushed back into the first rod to a retracted position, the respective first engaging portions of the engaging element will be pressed against the respective upper abutting surfaces of the hexagonal ball to hold the hexagonal ball between the bottom surface of the receiving groove and the first engaging portions, and when the second rod is pulled outwards relative to the first rod to an outward-extended position, the respective second engaging portions of the engaging element will be pressed against the lower abutting surfaces of the hexagonal ball to hold the hexagonal ball between the second engaging portions and an opening of the receiving groove. The limiting element is disposed at the opening of the receiving groove of the first rod for preventing the hexagonal ball from disengaging from the receiving groove. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIG. 1  is a cross-sectional view of a first conventional tool joint disclosed by Taiwan Patent No. 097208543; 
           [0012]      FIG. 2  is a cross-sectional view of a second conventional tool joint disclosed by Taiwan Patent No. 097207779; 
           [0013]      FIG. 3  is a cross-sectional view of a third conventional tool joint disclosed by Taiwan Patent No. 097203831; 
           [0014]      FIG. 4  is an exploded view of a two-section tool joint in accordance with the present invention; 
           [0015]      FIG. 5  is a perspective cross-sectional view of the two-section tool joint in accordance with the present invention; 
           [0016]      FIG. 6  is a cross-sectional view of the two-section tool joint in accordance with the present invention; 
           [0017]      FIG. 7  is a cross sectional view of the two-section tool joint in accordance with the present invention along line  7 - 7  of  FIG. 6 ; 
           [0018]      FIG. 8  is an operational view of the present invention, showing the second rod is pulled; 
           [0019]      FIG. 9  is an operational view of the present invention, showing the second rod extends from the first rod; 
           [0020]      FIG. 10  is an operational view of the present invention, showing the second rod is adjusted upwards; and 
           [0021]      FIG. 11  is an operational view of the present invention, showing that the second rod is adjusted downwards. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0022]    The present invention will be clearer from the following description when viewed together with the accompanying drawings, which show, for purpose of illustrations only, the preferred embodiment in accordance with the present invention. 
         [0023]    Referring to  FIGS. 4-7 , a two-section tool joint in accordance with a preferred embodiment of the present invention essentially comprises a first rod  40 , an engaging element  50 , a second rod  60  and a limiting element  70 . 
         [0024]    The first rod  40  includes a connecting portion  41  at one end thereof for connecting with a driving tool. The other end of the first rod  40  is defined with a receiving groove  42 , and on an inner surface of the receiving groove  42  are equidistantly provided six engaging protrusions  421 . Between each two neighboring engaging protrusions  421  is defined an engaging groove  422 . The inner surface of the receiving groove  42  is further provided with an annular flange  423  and an annular groove  424  which are located at an opening of the receiving groove  42 . 
         [0025]    The engaging element  50  includes a bottom  51  and six support arms  52  that are equidistantly arranged around the circumference of bottom  51  and extend in the same direction. Each of the support arms  52  includes a first inwards-bent engaging portion  521  and a second outwards-bent engaging portion  522  connected to the first engaging portion  521 . The first and the second engaging portions  521 ,  522  can restore to their original shapes after being deformed under pressure. The engaging element  50  is disposed in the receiving groove  42  of the first rod  40  in such a manner that the bottom  51  abuts against the bottom surface of the receiving groove  42 , the respective support arms  52  are located in the engaging grooves  422 , and the support arms  52  abut against the inner surface of the receiving groove  42 . The first and second engaging portions  521 ,  522  define a compression space A with respect to the inner surface of the receiving groove  42 . When the first and the second engaging portions  521 ,  522  are deformed under pressure, the compression space A will disappear, and when the first and the second engaging portions  521 ,  522  restore to their original shapes, the compression space A is formed again. 
         [0026]    The second rod  60  includes a driving portion  62  and a hexagonal ball  63  along an axis  61  thereof. Between the driving portion  62  and the hexagonal ball  63  are provided an annular protrusion  64  and a neck portion  65 . The driving portion  62  is used to engage with and rotate a corresponding a threaded fastener. The hexagonal ball  63  includes six upper abutting surfaces  631  and six lower abutting surfaces  632  that are arranged around the axis  61 . The upper abutting surfaces  631  are connected to the respective lower abutting surfaces  632 , and the upper and the lower abutting surfaces  631 ,  632  are formed along the axis  61 . Further, the respective lower abutting surfaces  632  are located farther from the driving portion  62  than the upper abutting surface  631 . The upper abutting surfaces  631  taper towards the driving portion  62  while the lower abutting surfaces  632  taper toward the direction opposite the driving portion  62 . The hexagonal ball  63  can be movably assembled in the receiving groove  42  of the first rod  40 . When the second rod  60  is pushed back into the first rod  40  to a retracted position, the respective first engaging portions  521  of the engaging element  50  will be pressed against the respective upper abutting surfaces  631  of the hexagonal ball  63  to hold the hexagonal ball  63  between the bottom surface of the receiving groove  42  and the first engaging portions  521 . When the second rod  60  is pulled outwards relative to the first rod  40  to an outward-extended position, the respective second engaging portions  522  of the engaging element  50  will be pressed against the lower abutting surfaces  632  of the hexagonal ball  63  to hold the hexagonal ball  63  between the respective second engaging portions  522  and the opening of the receiving groove  42 . 
         [0027]    Moreover, when the second rod  60  is pushed back into the first rod  40  to the retracted position, the annular protrusion  64  of the second rod  60  will abut against the annular flange  423  of the first rod  40 , so that the angle between the first and the second rods  40 ,  60  is locked and not adjustable. 
         [0028]    The limiting element  70  is annular and disposed in the annular groove  424  of the receiving groove  42  and engaged on the neck portion  65  of the second rod  60 . The inner diameter of the limiting element  70  is smaller than the outer diameter of the hexagonal ball of the second rod  60  for preventing the hexagonal ball  63  from disengaging from the receiving groove  42 . 
         [0029]    The aforementioned is the summary of the positional and structural relationship of the respective components of the preferred embodiment in accordance with the present invention. 
         [0030]    For a better understanding of the present invention, its operation and function, reference should be made to  FIG. 6 : when the second rod  60  is pushed back into the first rod  40  to the retracted position, (namely, the hexagonal ball  63  is pushed close to the bottom surface of the receiving groove  42 ), the engaging element  50  will hold the hexagonal ball  63  of the second rod  60  between the bottom surface of the receiving groove  42  and the respective first engaging portions  521 , meanwhile, the annular protrusion  64  of the second rod  60  will abut against the annular flange  423  of the first rod  40  to lock the angle between the first and the second rods  40 ,  60 . Therefore, the present invention can make the screwing/unscrewing operation requiring no angular adjustment smooth. 
         [0031]    As shown in  FIG. 8 , when the second rod  60  is pulled outwards relative to the first rod  40  to the outward-extended position (namely, the hexagonal ball  63  is pulled outwards away from the bottom surface of the receiving groove  42 ), first, since the outer diameter of the middle portion of the hexagonal ball  63  is the greatest, during the disengaging process of the upper abutting surfaces  631  of the hexagonal ball  63  and the first engaging portions  521 , the inwards-bent first engaging portions  521  will be pressed by the middle portion of the hexagonal ball  63  to deform, in addition, the second engaging portions  522  which are connected with the first engaging portions  521  will be consequently deformed, at this moment, the compression space A defined by the first, the second engaging portions  521 ,  522  with respect to the inner surface of the receiving groove  42  will disappear. 
         [0032]    As shown in  FIG. 9 , when the middle portion of the hexagonal ball  63  passes through the joints of the first and the second engaging portions  521 ,  522 , the second engaging portions  522  of the engaging element  50  will not be pressed any longer and can restore to their original shapes, namely, restore to the outwards-bent state, at this moment, the compression space A defined by the first, the second engaging portions  521 ,  522  with respect to the inner surface of the receiving groove  42  will be formed again. 
         [0033]    Finally, the second engaging portions  522  which have restored to their original shapes will be pressed against the low abutting surfaces  632  of the hexagonal ball  63  correspondingly, so that the hexagonal ball  63  can be held between the respective second engaging portions  522  and the limiting element  70 . 
         [0034]    Hence, as shown in  FIGS. 10 and 11 , when the second rod  60  is pulled outwards relative to the first rod  40  to the outward-extended position, the first rod  40  and the second rod  60  can be bent at multiple angles. No matter how the first and the second rods  40 ,  60  are bent, at least one of the second engaging portions  522  will be pressed against the lower abutting surfaces  632  of the hexagonal ball  63 . Moreover, after the second engaging portions  522  are pressed against the lower abutting surfaces  632  of the hexagonal ball  63 , the working direction is the same as the direction in which the first rod  40  and the second rod  60  retract toward or extend from each other, so that the tool joint of the present invention can be positioned stably in a multi-angle screwing/unscrewing operation, avoiding the retraction of the tool joint and reducing the difficulty and inconvenience of the screwing/unscrewing operation. 
         [0035]    While we have shown and described various embodiments in accordance with the present invention, it is clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.