The present invention relates to a hand tool and, more particularly, to a screwdriver tip (or head) structure.
A conventional compound screwdriver head was disclosed in the U.S. Pat. No. 7,322,265 (or Taiwanese Patent Publication No. TW-M289681), and comprises a body 20, a first working portion 21, a connecting surface 22, a second working surface 23, an awl portion 24 and a plurality of working grooves 25. One end of the first working portion 21 is connected with the body 20, and the other end is connected with an outer ring 221 of a plurality of connecting surfaces 22. An inner ring 222 of the connecting surface 22 is connected with the second working portion 23. The size of the outer ring 221 is larger than that of the inner ring 222, and the awl portion 24 is formed on the end of the connecting surface 22, the working grooves 25 are extended from the awl portion 24 to the first working portion 21 via the second working portion 23. The first working portion 21 is formed on the cylindrical body 20, including four abutting surfaces 211. The inner ring 222 of the connecting surface 22 is connected with a second abutting surface 231 of the second working portion 23. Similarly, the second working portion 23 includes four second abutting surfaces 231. The screwing and unscrewing of the small bolt as shown in
However, the conventional compound screwdriver head has the following disadvantages.
1. An angle is defined between the connecting surface 22 and the second abutting surface 231 of the second working portion 23 so that the inner ring 222 of the connecting surface 22 has a corner. In such a manner, when the second abutting surface 231 of the second working portion 23 rotates the bolt 40, the inner ring 222 cannot distribute the stress applied on the second abutting surface 231. Thus, the stress is concentrated on the inner ring 222 so that the inner ring 222 is easily broken during operation of the body 20.
2. When the first working portion 21 or the second working surface 23 rotates the bolt 30, the first abutting surface 211 of the first working portion 21 cannot provide an antiskid effect to the bolt 30, and the second abutting surface 231 of the second working portion 23 cannot provide an antiskid effect to the bolt 30.
In accordance with the present invention, there is provided a screwdriver tip structure comprising a main body provided with an operation end. The operation end is provided with multiple first working sections and multiple second working sections. The first working sections and the second working sections are arranged alternately and annularly along an axis of the operation end. Each of the first working sections has a convex shape. Each of the second working sections has a concave shape. Each of the first working sections is provided with multiple grooves. The grooves are spaced and arranged linearly. Each of the first working sections has a first end and a second end. The second end has a diameter more than that of the first end. Each of the first working sections has a periphery provided with a phantom side face. The side face extends from the second end to the first end. Each of the grooves is provided with a first concave face. The first concave face of each of the grooves includes a first single arc.
According to the primary advantage of the present invention, the multiple first single arcs distribute the stress when the operation end drives and rotates the screw member to prevent the operation end from being broken at the grooves during operation of the operation end, thereby enhancing the lifetime of the operation end.
According to another advantage of the present invention, the multiple concave faces provide more contact areas to the operation end so that the multiple concave faces provide a better rotational force when the operation end touches the first face of the screw member.
Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings.
Referring to the drawings and initially to
Each of the first working sections 12 is provided with multiple grooves 121. The grooves 121 are spaced and arranged linearly. The grooves 121 are parallel with each other. Each of the grooves 121 has the same depth. Each of the first working sections 12 has three, four, five or six grooves 121. Each of the first working sections 12 has a first end 122 and a second end 123. The second end 123 has a diameter more than that of the first end 122. Each of the first working sections 12 has a periphery provided with a phantom side face 124. The side face 124 extends from the second end 123 to the first end 122. The side face 124 is an inclined plane. The side face 124 has a straight shape.
As shown in
The center of the first single arc 126 is outside of the operation end 11. The first distance 1271 is less than a radius of the first single arc 126 or less than a half of the radius of the first single arc 126. The second distance 128 is more than the radius of the first single arc 126. The second distance 128 is more than the third distance 129 or is double of the third distance 129. The second distance 128 is more than the first distance 1271. The third distance 129 is close to the first distance 1271 or equal to the first distance 1271.
The operation end 11 is provided with an end portion 14. The end portion 14 has a conic shape. The end portion 14 has a center provided with a second concave face 141. The second concave face 141 includes a second single arc 142 which is constructed by a phantom circle. The first end 122 is arranged between the second end 123 and the end portion 14.
The second single arc 142 is outside of the operation end 11. The second single arc 142 is larger than the first single arc 126.
In fabrication, the first concave face 125 closest to the second end 123 is worked and formed initially. Then, the first concave face 125 of each of the grooves 121 is worked and formed serially from the second end 123 to the first end 122. In such a manner, the first working sections 12 are formed. Then, the second concave face 141 is worked and formed. Finally, the second working sections 13 are worked and formed, and the first working sections 12 are divided by the second working sections 13. Thus, the operation end 11 is formed.
In operation, referring to
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Accordingly, the screwdriver tip structure of the present invention has the following advantages.
1. The multiple first single arcs 126 distribute the stress when the operation end 11 drives and rotates the screw member 20 to prevent the operation end 11 from being broken at the grooves 121 during operation of the operation end 11, thereby enhancing the lifetime of the operation end 11.
2. The multiple concave faces 125 provide more contact areas to the operation end 11 so that the multiple concave faces 125 provide a better rotational force when the operation end 11 touches the first face 21 of the screw member 20.
3. The second face 22 of the screw member 20 extends into the second concave face 141 of the end portion 14 when the operation end 11 is placed in the first face 21 to increase the contact area between the first working sections 12 of the operation end 11 and the screw member 20 so that the end portion 14 and the first working sections 12 are closely fit in the first face 21 of the screw member 20, to prevent the operation end 11 from being worn out due to a relative friction when the operation end 11 drives and rotates the screw member 20, to increase the operational torque, and to distribute the stress. The second face 22 of the screw member 20 is received in the second concave face 141 of the end portion 14, so that the main body 10 keeps the end portion 14, and the operation end 11 has a shape similar to that of the conventional screwdriver tip structure. In general, the end portion 14 increase the rotational torque and is mounted easily and conveniently.
4. Each of the first working sections 12 is provided with at least three grooves 121 so that the operation end 11 is used for operating the screw member 20 of three different sizes and specifications.
5. The first working sections 12 are available for a Torx screwdriver tip, a flat screwdriver tip or a hex wrench to enhance the versatility of the screwdriver tip structure of the present invention.
Although the invention has been explained in relation to its preferred embodiment(s) as mentioned above, it is to be understood that many other possible modifications and variations can be made without departing from the scope of the present invention. It is, therefore, contemplated that the appended claim or claims will cover such modifications and variations that fall within the scope of the invention.