Abstract:
A rotatable tool handle comprises a first part and a second part which can be switched between an in-line position and an angle position. Further, the locking structure for fixing the first and second parts is disposed between the connecting structures of the first and second parts, so that the engaging points of the first and second parts lie on the rotation axis of the two parts. Moreover, the portion of the first part for forming the recess is harder than the rest of the first part, and the portion of the second part for forming the pivot portion is harder than the rest of the second part, so as to enhance the structural strength of the engaging structure of the first and second parts of the handle.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a tool handle, and more particularly to a rotatable tool handle which is capable of being switched between an in-line position and an angle position. 
         [0003]    2. Description of the Prior Art 
         [0004]    A conventional rotatable screwdriver handle  10  as shown in  FIGS. 1A ,  1 B and  2  comprises an upper part  11  and a lower part  12 , which are each provided with a slanted end surface  111 ,  121 . The end surface  121  of the lower part  12  is formed with an axial protrusion  122  to be inserted in a concave  112  of the end surface  111  of the upper part  11 . In the concave  112  is further formed a recess  113 , and in the recess  113  is defined an assembling hole  114  which penetrates through the circumferential surface of the upper part  11 . A pin  13  is inserted through the recess  113  and into the assembling hole  114 . The axial protrusion  122  of the lower part  12  is formed with two cavities  123 , and in each of the cavities  123  is disposed a spring  14  and an engaging member  15 . Pressing the pin  13  can make the engaging member  15  disengage from the recess  113  of the upper part  11  of the handle  10 , which allows the upper and lower parts  11 ,  12  of the handle  10  to be switchable to an in-line state or an angled state. When the pin  13  is released from being pressed, one of the engaging members  15  will be pushed by the spring  14  into the recess  113  of the upper part  11 , so that the upper and lower parts  11 ,  12  of the handle  10  are fixed relative to each other. This screwdriver handle  10  is structurally complicated and not easy to assemble. 
         [0005]      FIG. 3  shows another rotatable handle  10 , wherein the slanted end surface  121  of the lower part  12  is formed both sides of the axial protrusion  122  with two cavities  124 , and the spring  14  and an engaging member  15  are provided on the upper part  11 . Pressing or releasing a control member  16  can make the engaging member  15  slide back into the upper part  11  of the handle  10  or extend into the cavities  124  of the lower part  12 , so as to make the upper and lower parts  11 ,  12  switchable or fixed with respect to each other. 
         [0006]    It is to be noted that the handle  10  has only a single engaging. member  15  engaged in the cavities  124  to fix the upper and lower parts of the handle, and the cavities  124  are formed on the lower part  12  with an inferior rigidity, the engagement structure between the engaging member  15  and the cavities  124  has a relatively weak structural strength, namely, the engaging member  15  and the cavities  124  are likely to be broken when a force applied to rotate the handle  10  is relatively large. 
         [0007]    The present invention has arisen to mitigate and/or obviate the afore-described disadvantages. 
       SUMMARY OF THE INVENTION 
       [0008]    The primary object of the present invention is to provide a rotatable tool handle, wherein the handle comprises a first part and a second part which can be switched between an in-line position and an angle position. Further, the locking structure for fixing the first and second part is disposed between the connecting structures of the first and second parts, so that the engaging points of the first and second parts lie on the rotation axis of the two parts. Moreover, the portion of the first part for forming the recess is harder than the rest of the first part, and the portion of the second part for forming the pivot portion is harder than the rest of the second part, so as to enhance the structural strength of the engaging structure of the first and second parts of the handle. 
         [0009]    To achieve the above object, a rotatable tool handle comprises a first part and a second part. The first part is formed with a first slanted end surface at one end thereof, the first slanted end surface is formed at a center thereof with a recess, and a first engaging cavity is formed at a bottom of the recess. The second part is formed with a second slanted end surface at one end for mating with the first slanted end surface, the second slanted end surface is formed with a pivot portion to be inserted in the recess of the first part. At an end surface of the pivot portion is a second engaging cavity formed in the shape of the first engaging cavity, on a peripheral surface of the second part is defined an assembling cavity, and a penetrating hole is formed at a bottom of the second engaging cavity and extending to the assembling cavity. The first and second engaging cavities each have at least two pairs of opposite ends. A control member is movably disposed in the assembling cavity of the second part. A pin includes an operating end to be inserted in the penetrating hole of the second part and pushed against by the control member, and a drive end to be inserted in the second engaging cavity. An engaging member is formed in the shape of the first and second engaging cavities and engaged in the first engaging cavity, the engaging member is aligned with and capable of engaging with the second engaging cavity after the second part rotates 180 degrees. An elastic member is disposed between the engaging member and the first engaging cavity in such a manner that the engaging member is pushed against the drive end of the pin by the elastic member, and the pin is pushed by the control member to selectively keep the engaging member between the first and second engaging cavities or to push the engaging member back into the first engaging cavity. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1A  is a cross sectional view of a conventional screwdriver handle; 
           [0011]      FIG. 1B  is an operational view of the screwdriver handle of  FIG. 1A ; 
           [0012]      FIG. 2  shows that the conventional screwdriver handle is switched to an angled position; 
           [0013]      FIG. 3  shows another conventional screwdriver handle; 
           [0014]      FIG. 4  is an exploded view of a rotatable tool handle in accordance with a first embodiment of the present invention; 
           [0015]      FIG. 5  is an assembly view of the rotatable tool handle in accordance with the first embodiment of the present invention; 
           [0016]      FIG. 6A  is a cross sectional view of the rotatable tool handle in accordance with the first embodiment of the present invention; 
           [0017]      FIG. 6B  is an operational view of  FIG. 6A ; 
           [0018]      FIG. 7A  is a cross sectional view showing that the tool handle of the present invention is switched 90 degrees to an angled position; 
           [0019]      FIG. 7B  is a cross sectional view showing that the tool handle of the present invention is switched 180 degrees to an in-line position; 
           [0020]      FIG. 8A  is a cross sectional view of the present invention showing that the tool handle is locked in an angled position; 
           [0021]      FIG. 8B  is a cross sectional view of the present invention showing that the tool handle is in an angled position, and the first and second parts are not locked with each other; 
           [0022]      FIG. 9A  is an axial cross sectional view showing that the tool handle of another embodiment of the present invention is switched 90 degrees to an angled position; 
           [0023]      FIG. 9B  is an axial cross sectional view showing that the tool handle of another embodiment of the present invention is switched 180 degrees to an in-line position; 
           [0024]      FIG. 10A  is a longitudinal cross sectional view showing that the tool handle of another embodiment of the present invention is switched 90 degrees to an angled position; and 
           [0025]      FIG. 10B  is a longitudinal cross sectional view showing that the tool handle of another embodiment of the present invention is switched 180 degrees to an in-line position. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0026]    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. 
         [0027]    Referring to  FIGS. 4 ,  5 ,  6 A,  7 A and  8 A, a rotatable tool handle in accordance with a first embodiment of the present invention is shown, wherein the rotatable tool handle comprises a first part  20  and a second part  30 . The positioning device is disposed between the first and second parts  20 ,  30  of the tool handle and comprises a control member  40 , a pin  50 , a positioning member  60 , an engaging member  70  and an elastic member  80 . 
         [0028]    The first part  20  is formed with a first slanted end surface  21  at one end thereof and a chamber  25  at another end thereof. The chamber  25  is sealed with a cover  26 . The first slanted end surface  21  is formed at the center thereof with a recess  22 , an annular groove  221  is formed around the inner surface of the recess  22 , a first engaging cavity  23  is formed at a bottom of the recess  22 , and a receiving cavity  24  is formed at a bottom surface  231  of the first engaging cavity  23 . The first engaging cavity  23  is formed with at least two pairs of opposite ends. In this embodiment, the first engaging cavity  23  is cross-shaped and has two opposite first ends  232  and two opposite second ends  233 , and the first ends  232  are wider than the second ends  233 . The first engaging cavity  23  can also be square-shaped or rectangular-shaped. The inner surface of the recess  22  and the first engaging cavity  23  are perpendicular to the first slanted end surface  21 , and the bottom surface  231  of the first engaging cavity  23  is parallel to the first slanted end surface  21 . 
         [0029]    The second part  30  is formed with a second slanted end surface  31  at one end for mating with the first slanted end surface  21 , and an assembling hole  36  at another thereof for assembling a work piece. The second slanted end surface  31  is formed with a pivot portion  32  to be inserted in the recess  22  of the first part  20 . Around the circumferential surface of the pivot portion  32  is formed an annular groove  321  to be aligned with the annular groove  221  of the first part  20 , and at an end surface of the pivot portion  32  is formed a second engaging cavity  33  formed in the shape of the first engaging cavity  23 . On the peripheral surface of the second part  30  is defined an assembling cavity  34 , and a penetrating hole  35  is formed at the bottom of the second engaging cavity  33  and extends to the assembling cavity  34 . 
         [0030]    In this embodiment, the peripheral surface of the pivot portion  32  of the second part  30  and the inner surface of the second engaging cavity  33  are perpendicular to the second slanted end surface  31 . The second engaging cavity  33  is cross-shaped and has two opposite first ends  331  and two opposite second ends  332 , and the first ends  331  are wider than the second ends  332 . 
         [0031]    The control member  40  is movably disposed in the assembling cavity  34  of the second part  30 , and inside the control member  40  is formed with a push portion  41 . 
         [0032]    The pin  50  includes an operating end  501  to be inserted in the penetrating hole  35  of the second part  30  and pushed against by the control member  40 , and a drive end  502  to be inserted in the second engaging cavity  33 . In this embodiment, as shown in  FIG. 6A , the pin  50  is provided with a slide surface  52  at the operating end  501  and a push surface  51  at the drive end  502 . The slide surface  52  and the push surface  51  are parallel to the second slanted end surface  31  of the second part  30 , the slide surface  52  is pushed against the push portion  41  of the control member  40 , and the push surface  51  is pushed against the engaging member  70 . The drive end  502  of the pin  50  is further provided with an abutting surface  53  which is perpendicular to the push surface  51  and located toward the inner surface of the second engaging cavity  33 , and the abutting surface  53  is designed to reduce friction between the pin  50  and the inner surface of the second engaging cavity  33 . 
         [0033]    The positioning member  60  in this embodiment is a C-ring formed with a notch  61  and disposed between the annular grooves  221 ,  321  of the pivot portion  32  of the second part  30  and the first part  20  to pivotally connect the first and second parts  20 ,  30  of the handle. 
         [0034]    The engaging member  70  is cross-shaped, formed in the shape of the first and second engaging cavities  23 ,  33  and includes two opposite first ends  71  and two opposite second ends  72  which are wider than the two first ends  71 . The engaging member  70  has the two first ends  71  engaged in the first ends  232  of the first engaging cavity  23  and has the second ends  72  engaged in the second ends  233  of the first engaging cavity  23 . The engaging member  70  is further formed with a receiving cavity  73  to be aligned with the receiving cavity  24  of the first part  20 . 
         [0035]    The elastic member  80  is disposed between the receiving cavity  73  of the engaging member  70  and the receiving cavity  24  of the first part  20  in such a manner that the engaging member  70  is pushed against the drive end  502  of the pin  50  by the elastic member  80 , and the pin  50  is pushed by the control member  40  to selectively keep the engaging member  70  between the first and second engaging cavities  23 ,  33  or to push the engaging member  70  back into the first engaging cavity  23 . 
         [0036]    The portion of the first part  20  for forming the recess  22  is harder than the rest of the first part  20 , and the portion of the second part  30  for forming the pivot portion  32  is harder than the rest of the second part  30 . 
         [0037]    What mentioned above are the structural relations of the main components of the present invention, for a better understanding of its operation and function, reference should be made to  FIGS. 6A-8B . 
         [0038]    As shown in  FIG. 6A , the first and second parts  20 ,  30  of the handle are maintained in an in-line state, and the first and second slanted end surfaces  21 ,  31  define an angle θ, which is preferably 45 degrees, with respect to an axial direction X of the first and second parts  20 ,  30 . In normal conditions (when the control member  40  is not being pushed), the elastic member  80  pushes the engaging member  70  to a position between the first and second engaging cavities  23 ,  33 , meanwhile, the pin  50  is pushed toward the control member  40 , and the push surface  51  of the pin  50  is abutted against the center of the engaging member  70 . When the control member  40  is pushed to make the push surface  51  of the pin  50  slide against the engaging member  70 , the engaging member  70  will be pushed into the first engaging cavity  23  in such a manner that the top surface of the engaging member  70  is flush with the first slanted end surface  21 , and the push surface  51  of the pin  50  is flush with the second slanted end surface  31 , as shown in  FIG. 6B , so that the first and second parts  20 ,  30  are switchable with respect to each other. 
         [0039]      FIG. 7A  shows that after the second part  30  is switched 90 degrees with respect to the first part  20  to an angled position, the first and second slanted end surfaces  21 ,  31  will be misaligned with each other, and so will be the first and second engaging cavities  23 ,  33  in such a manner the first ends  232  of the first engaging cavity  23  are aligned with the second ends  332  of the second engaging cavity  33 , while the second ends  233  of the first engaging cavity  23  are aligned with the first ends  331  of the second engaging cavity  33 , thus preventing the engaging member  70  from moving into the second engaging cavity  33 .  FIG. 7B  shows that after the second part  30  is switched  180  degrees with respect to the first part  20  to an in-line position, the first and second slanted end surfaces  21 ,  31  will be aligned with each other, and so will be the first and second engaging cavities  23 ,  33  in such a manner the first ends  232  of the first engaging cavity  23  are aligned with the first ends  331  of the second engaging cavity  33 , while the second ends  233  of the first engaging cavity  23  are aligned with the second ends  332  of the second engaging cavity  33 , so that the engaging member  70  can be pushed into the second engaging cavity  33 , and thus the first and second parts  20 ,  30  are fixed from rotating with respect to each other, as shown in  FIG. 8A . Referring then to  FIG. 8B , just pushing the control member  40  can allow the first and second parts  20 ,  30  to be switched to the in-line position from the angled position. 
         [0040]    It is to be noted that, as shown in  FIGS. 9A and 9B , the first and second engaging cavities  23 ,  33  can also be a square-shaped cavity with two opposite first edges  234 ,  333  and two opposite second edges  235 ,  334 . The engaging member  70  is also a square-shaped structure with two opposite first edges  73  and two opposite second edges  74  for abutting against the opposite first edges  234 ,  333  and the two opposite second edges  235 ,  334  of the first and second engaging cavities  23 ,  33 . As shown  FIG. 9A , after the second part  30  is switched  90  degrees with respect to the first part  20  to an angled position, the first and second edges  234 ,  235  of the first engaging cavity  23  are aligned with the second and first edges  334 ,  333  of the second engaging cavity  33 , respectively. When the second part  30  is switched 180 degrees with respect to the first part  20  to an in-line position, as shown in  FIG. 9B , the first and second edges  234 ,  235  of the first engaging cavity  23  are aligned with the first and second edges  333 ,  334  of the second engaging cavity  33 , respectively. The first and second engaging cavities  23 ,  33  can also be hexagonal, octagonal, and etc as along as it has an even number of edges. 
         [0041]    Referring then to  FIGS. 10A and 10B , another embodiment of the present invention is shown and similar to the first embodiment except that: another end of the first part  20  opposite the first slanted end surface  21  is formed with an assembling cavity  27  for engaging with a work piece, and another end of the second part  30  opposite the second slanted end surface  31  is formed with a chamber  37  for reception of tool heads, and the chamber  37  is sealed with a cover  38 . 
         [0042]    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.