Patent Publication Number: US-8973474-B2

Title: Screwdriver bit structure having auxiliary positioning function

Description:
FIELD OF THE INVENTION 
     The present invention relates to a screwdriver bit structure, and more particularly to a screwdriver bit structure that has auxiliary positioning function. 
     BACKGROUND OF THE INVENTION 
     According to a conventional technique shown in U.S. design Pat. D410,372 entitled “screwdriver bit”, its appearance showed that the upper section portion is a hexagon shaft where the lower section portion has a circular shaft. A protruding ring section with larger exterior diameter is formed to the upper position of the circular shaft where a cross driving portion is formed to the lower position of the circular shaft. Since the foregoing conventional technique belonged to the design patent, it may not understand that how can the protruding ring section disposed to the upper position of the circular shaft work; and further it may not understand that whether the protruding ring section is integrated with or connected to the circular shaft. 
     Therefore, the screwdriver bit structure having the appearance that is similar to the protruding ring section for sale on market can be approximately divided into two categories. 
     First, the protruding ring section is integrated with the screwdriver bit through the forging process. Afterward, the external surface of the protruding ring section is coated with colors for recognition purpose. 
     Second, the protruding ring section with colors is directly combined with a predetermined place of the screwdriver bit through plastic injection. The protruding ring section can closely cover the shaft of the screwdriver bit through the combination manner so as to firmly achieve the integration. Consequently, the protruding ring section cannot be rotated individually. At the most, the efficiency can merely provide recognition purpose. 
     Upon the foregoing technique, no matter which technique is used to complete U.S. design Pat. D410,372, the protruding ring section is integrated with the screwdriver bit through consolidation to achieve the color recognition function and the protruding ring section may not perform independent rotation by itself as well. 
     Accordingly, to overcome the foregoing shortcomings, the inventor(s) of the present invention based on years of experience in the related field to conduct extensive researches and experiments for the screwdriver structure with the auxiliary sheath, and finally invented a screwdriver bit structure having auxiliary positioning function. 
     SUMMARY OF THE INVENTION 
     A primary objective of the present invention is to provide a screwdriver bit structure having auxiliary positioning function that is held by hands and used for positioning the screwdriver bit to prevent the screwdriver bit from offsetting and coming off while rotating the screwdriver bit. 
     To achieve the foregoing objective, the screwdriver bit structure having auxiliary positioning function comprises a screwdriver bit and an auxiliary sheath. One end of the screwdriver bit is a circular cylinder. The front of the circular cylinder has a driving portion where another end has a fitting portion with a polygon. The circular cylinder has a concave ring groove near the front of the driving portion. The auxiliary sheath is sheathed to a periphery of the driving portion of the circular cylinder, and is a long tube body that has a tube hole passing through the tube body. 
     A protruding ring is disposed in an internal wall of the tube hole, and can be fastened to the concave ring groove of the circular cylinder. Two sides of the protruding ring within the tube hole form a long inserting portion and a short inserting portion. The long inserting portion covers a portion of the driving portion where the short inserting portion covers a portion of the circular cylinder. Accordingly, the screwdriver bit showing fastening state can independently move with the auxiliary sheath so that the screwdriver bit can be positioned without generating any shake while holding the auxiliary sheath. When the screwdriver bit is rotably locked, the screwdriver bit can effectively and stably rotate to prevent the screwdriver bit from offsetting and coming off. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a decomposition drawing illustrating a structure according to a preferred embodiment of the present invention; 
         FIG. 2  is an assembly drawing illustrating a structure according to a preferred embodiment of the present invention; 
         FIG. 3  is a cross-sectional drawing of front view assembly illustrating the structure according to a preferred embodiment of the present invention; 
         FIG. 4  is a side-view drawing illustrating the structure according to a preferred embodiment of the present invention; 
         FIG. 5  is a decomposition drawing illustrating the structure according to a preferred embodiment II of the present invention; 
         FIG. 6  is an assembly drawing illustrating the structure according to a preferred embodiment II of the present invention; 
         FIG. 7  is a cross-sectional drawing of front view assembly illustrating the structure according to a preferred embodiment II of the present invention; 
         FIG. 8  is a side-view drawing illustrating the structure according to a preferred embodiment II of the present invention; 
         FIG. 9  is a decomposition drawing illustrating the structure according to a preferred embodiment III of the present invention; 
         FIG. 10  is an assembly drawing illustrating the structure according to a preferred embodiment III of the present invention; 
         FIG. 11  is a cross-sectional drawing of front view assembly illustrating the structure according to a preferred embodiment III of the present invention; 
         FIG. 12  is a side-view drawing illustrating the structure according to a preferred embodiment III of the present invention; 
         FIG. 13  is a schematic drawing illustrating an auxiliary sheath according to another embodiment of the present invention; and 
         FIG. 14  is a schematic drawing illustrating an auxiliary sheath according to a further embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Other features and advantages of the present invention will become apparent from the following description of the invention which refers to the accompanying drawings. 
     First, please refer to  FIG. 1  to  FIG. 4 , a screwdriver bit structure having auxiliary positioning function is shown according to a preferred embodiment I of the present invention, and composed of a screwdriver bit  10  and an auxiliary sheath  20 . An end of the screwdriver bit  10  is a circular cylinder  11 . A front of the circular cylinder  11  has a driving portion  12 . Another end of the circular cylinder  11  is a fitting portion  13 . The front of the driving portion  12  is any one of a slotted type, a cross type, and a polygon type. The circular cylinder  11  has a concave ring groove  111  near the front of the driving portion  12 . The fitting portion  13  of the circular cylinder  11  is a polygon column. An arc groove  131  is further disposed to a middle section of the polygon column so as to connect a screwdriver bar (not shown in the figure). 
     The auxiliary sheath  20  is a long tube body through plastic injection, and has a tube hole  21  passing through the tube body along an axial direction. The internal diameter of the tube hole  21  is slightly greater than the external diameter of the circular cylinder  11 . A protruding ring  22  is disposed near a side edge of the internal wall of the tube hole  21 . Accordingly, two sides of the protruding ring  22  of the tube hole  21  form a long inserting portion  23  and a short inserting portion  24 . 
     With the foregoing components, when the tube hole  21  of the auxiliary sheath  20  is fitted with the circular cylinder  11  of the screwdriver bit  10  and the protruding ring  22  of the auxiliary sheath  20  is buckled to the concave ring groove  131  for positioning, the long inserting portion  23  of the auxiliary sheath  20  covers a portion of the driving portion  12  where the short inserting portion  24  covers a periphery of the circular cylinder  11  so that the auxiliary sheath  20  assembled to the screwdriver bit  10  can achieve the absolute solidification to prevent coming off. When a hand holds the auxiliary sheath  20  under stop state, the screwdriver bit  10  can be freely and randomly rotated. 
     Therefore, while rotating the screwdriver bit  10 , the screwdriver bit  10  can be accurately positioned by holding the auxiliary sheath  20  to prevent the screwdriver bit  10  from offsetting or prevent the screwdriver bit  10  from coming off during the rotation. 
     Moreover, referring to  FIG. 5  to  FIG. 8 , a screwdriver bit structure having auxiliary positioning function is shown according to a preferred embodiment II of the present invention. The main technical features shown in the embodiment is completely the same as the foregoing embodiment. The structure is composed of a screwdriver bit  10  and an auxiliary sheath  20 . The circular cylinder  11  of the screwdriver bit  10  has a concave ring groove  111  near the end portion of the driving portion  12 . The auxiliary sheath  20  has a protruding ring  22  that can be fitted to the concave ring groove  111 . Its structural difference is that the fitting portion  13  as a polygon cylinder of the screwdriver bit  10  has a plurality of gaps  132  at adjacent intersections to buckle the screwdriver bars with different types. 
     Referring to  FIG. 9  to  FIG. 12 , a screwdriver bit structure having auxiliary positioning function is shown according to a preferred embodiment III of the present invention. The technical features shown in the embodiment is extended from the foregoing embodiments. The structure is composed of a screwdriver bit  10  and an auxiliary sheath  20 . A driving portion  12  is disposed to an end of the screwdriver bit  10 , and is at the front of the polygon cylinder  14 . A concave ring groove  111  is disposed to a front of the polygon cylinder  14  near the driving portion  12 . Further, the auxiliary sheath  20  has a protruding ring  22  that can be fitted to the concave ring groove  111  for positioning. 
     The length of the screwdriver bit  10  shown in the embodiment III is a shorter specification, and has a plurality of gaps  132  at predetermined positions of the fitting portion  13  as the polygon cylinder to buckle the screwdriver bars with different types. 
     Referring to  FIGS. 13 and 14 , an external surface of the auxiliary sheath  20  of the present invention can have the non-slip portions  25 . The non-slip portions  25  are embossments that are uniformly distributed to the external periphery of the auxiliary sheath  20  as shown in  FIG. 13  so as to increase the surface roughness. Of course, a plurality of circular cavities (not shown in the figure) can be utilized to replace the foregoing embossments to achieve the goal of increasing the surface roughness of the auxiliary sheath  20  as well. In addition, as shown in  FIG. 14 , the non-slip portions  25  can be multiple long cavities arranged in parallel. The disposition direction of the long cavities is parallel the center axis of the auxiliary sheath  20 . 
     Although the features and advantages of the embodiments according to the preferred invention are disclosed, it is not limited to the embodiments described above, but encompasses any and all modifications and changes within the spirit and scope of the following claims.