Patent Publication Number: US-2016236332-A1

Title: Driving head

Description:
BACKGROUND OF THE INVENTION 
     1. Fields of the Invention 
     The present invention relates to a driving head, and more particularly, to a driving head having a driving section for holding and driving a screw-type object. 
     2. Descriptions of Related Art 
     The conventional driving head for holding and driving a screw-type object is disclosed in  FIGS. 9 to 11 , and comprises a body  30  which includes a connection portion  31  and a driving portion  32  on two ends thereof. The connection portion  31  has a polygonal recess to be connected with a tool, and the driving portion  32  is a straight shank whose outer surface is parallel with the axis of the driving head. The driving portion  32  has a driving section  321  which has six engaging faces which are located at equal center angle  322  to each other. Each engaging face has two sides, each side is combined with another side of the adjacent engaging face to form an abutment side. The angle  323  between the two abutment sides is 60 degrees. A curved neck  33  is connected between the connection portion  31  and the driving portion  32 . As shown in  FIGS. 10 and 11 , the driving portion  32  is a straight shank which is easily deformed when being applied with teat treatment, this is especially obvious for the length of the body  30  is over 200 mm. 
     Another conventional driving head is disclosed in U.S. Pat. No. 5,105,690 wherein the driving portion comprises a tapered section and a straight section. Again, the straight section tends to be deformed when being applied with teat treatment. There is a gap between the straight section and the inner periphery of the socket, so that the socket tends to be broken after frequent use. 
     The present invention intends to provide a driving head to eliminate the shortcomings mentioned above. 
     SUMMARY OF THE INVENTION 
     The present invention relates to a driving head having a driving section for holding and driving a screw-type object, and the driving head comprises a body having a connection portion and a driving portion which extends integrally from the first end of the connection portion. The connection portion has a polygonal recess defined in the second end thereof. The outer diameter of the driving portion is smaller than that of the connection portion. The driving portion has a driving section formed on the distal end thereof, and the driving section has multiple engaging faces defined in the outer periphery thereof. The engaging faces are located at equal center angle to each other. A neck is connected between the connection portion and the driving portion. The neck is a recessed and curved neck. The center of the curvature of the neck is located at outside of the body. The driving portion is a tapered portion. A first angle is defined between the outer surface of the driving portion and the axis of the body. The outer diameter of the driving section is smaller than the outer diameter of the driving portion. An object has a reception recess in which the driving section is inserted. The reception recess has a tapered angle. The first angle is smaller than or equal to the tapered angle. The distal end of the driving section reaches the inner end of the reception recess when the driving section is inserted into the reception recess. 
     The primary object of the present invention is to provide a driving head wherein the driving portion is strong and is not easily deformed. The driving section is sufficiently engaged with the reception recess of the object. 
     The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view to show the driving head of the present invention; 
         FIG. 2  is a front view of the driving head of the present invention; 
         FIG. 3  is a cross sectional view, taken along line B-B in  FIG. 2 ; 
         FIG. 4  is an enlarged view of the circled portion C in  FIG. 2 ; 
         FIG. 5  is an end view to show the polygonal recess of the connection portion of the driving head of the present invention; 
         FIG. 6  is a cross sectional view to show that the driving head of the present invention is engaged with the object; 
         FIG. 7  is an enlarged view of the circled portion D in  FIG. 6 ; 
         FIG. 8  is a perspective view to show the second embodiment of the driving head of the present invention; 
         FIG. 9  is a front view of a conventional driving head; 
         FIG. 10  is a cross sectional view, taken along line B-B in  FIG. 9 , and 
         FIG. 11  is an enlarged view of the circled portion C in  FIG. 9 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to  FIGS. 1 to 4 , the driving head having a driving section for holding and driving a screw-type object, of the present invention comprises a body  10  having a connection portion  11  and a driving portion  12  which extends integrally from the first end of the connection portion  11 . The connection portion  11  has a polygonal recess  110  defined in the second end thereof so as to be connected with a tool which is not shown. The polygonal recess  110  is a rectangular recess. The outer diameter of the driving portion  12  is smaller than the outer diameter of the connection portion  11 . The driving portion  12  has a driving section  121  formed on the distal end thereof. The driving section  121  has six engaging faces  120  defined in the outer periphery thereof. The engaging faces  120  are located at equal center angle to each other around the central axis of the body  10 . A neck  13  is connected between the connection portion  11  and the driving portion  12 . The neck  13  is a recessed and curved neck. The center of the curvature of the neck  13  is located at outside of the body  10 S. An imaginary circSpecificationle  124  is formed at the distal end of the driving section  121 . Each engaging face  120  has a radius  126 . Each engaging face  120  is a recessed face and has two sides, the center angle of each engaging face  120  is 0.9 to 0.98 times of 60 degrees. Preferably, the center angle of each engaging face  120  is 0.9 to 0.95 times of 60 degrees. There is a curved face  122  formed between the two adjacent sides of two adjacent engaging faces  120 . 
     The driving portion  12  is a tapered portion. A first angle  123  is defined between the outer surface of the driving portion  12  and the axis of the body  10 . The outer diameter of the driving section  121  is smaller than the outer diameter of the driving portion  12 . 
     As shown in  FIGS. 5, 6 and 7 , an object  20  has a reception recess  21  in which the driving section  121  is inserted. The reception recess  21  has a tapered angle  22 , and the first angle  123  is smaller than or equal to the tapered angle  22 . The distal end of the driving section  121  reaches the inner end of the reception recess  21  when the driving section  121  is inserted into the reception recess  21 . 
     As shown in  FIG. 8  which shows the second embodiment and a gear-like shape is seen when viewed from the end of the driving section  121 . 
     The characters of the present invention are that the driving portion  12  is a tapered portion wherein the diameter of the driving portion  12  gradually reduces from the connection portion with the neck  13  toward the driving section  121 . The reception recess  21  has a tapered angle  22 , and the first angle  123  is smaller than or equal to the tapered angle  22 . When the driving section  121  is inserted into the reception recess  21 , because the first angle  123  is smaller than or equal to the tapered angle  22 , the distal end of the driving section  121  reaches the inner end of the reception recess  21 . 
     It is noted that the tapered driving portion  12  is a tapered portion so that it is not deformed when being applied with heat treatment. Furthermore, because the first angle  123  is smaller than or equal to the tapered angle  22 , when the driving section  121  is inserted into the reception recess  21 , the distal end of the driving section  121  reaches the inner end of the reception recess  21 . Therefore, the reception recess  21  is not broken during operation. 
     While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.