Abstract
A screwdriver includes a first section, a second section where a positioning groove is annularly formed, a sleeve member detachably disposed on the second section, and an engagement member disposed in the sleeve member. The sleeve member has a body with a through hole, a magnetic unit disposed in the through hole, and an accommodation groove adapted to accommodate the engagement member. When the second section and the sleeve member engage in position, the accommodation groove and the positioning groove meet to engage the engagement member with the positioning groove. The engagement between the second section and the sleeve member allows a gap to be formed between a screw head and the sleeve member while inserting the second section into a socket of the screw head, so the magnetic attraction exists without the contact between the sleeve member and the screw head for a firm engagement therebetween.
Claims
1. A screwdriver comprising a first section driven by a driving tool and a second section connected to said first section and adapted to engage with a socket of a screw head; wherein a positioning groove is annularly formed on an outer periphery of said second section, a sleeve member being detachably disposed on said outer periphery of said second section, said sleeve member including a body defining a top end and a bottom end, a through hole formed through said body for defining an inner peripheral wall between said top end and said bottom end, a magnetic unit disposed in said through hole and located opposite to said top end, and an accommodation groove recessed into said inner peripheral wall and formed opposite to said bottom end, with an engagement member disposed within said accommodation groove and with said second section adapted to pass through said through hole of said sleeve member, said accommodation groove being located in correspondence with said positioning groove for alignment therewith when said sleeve member is properly positioned on said second section to thereby engage said engagement member with said positioning groove and confirm achievement of a firm engagement between said sleeve member and said second section, a gap being formed between a top surface of said screw head and said bottom end of said sleeve member when said second section is properly engaged with said socket of said screw head.
2. The screwdriver according to claim 1, wherein a cover unit extends outwards from said bottom end of said sleeve member, said cover unit defining a room communicating with said through hole.
3. The screwdriver according to claim 2, wherein said cover unit includes a lower end and an upper end, said upper end being connected to said bottom end of said sleeve member, an inner diameter of said lower end being larger than an inner diameter of said upper end.
4. The screwdriver according to claim 2, wherein said room of said cover unit defines a maximum diameter larger than a diameter of said through hole of said sleeve member.
5. The screwdriver according to claim 1, wherein said gap ranges from 2 mm to 3 mm.
6. The screwdriver according to claim 1, wherein said second section is formed into a cruciform type, a square type, or a hexalobular type.
7. The screwdriver according to claim 1, wherein said sleeve member is positioned in the middle of said second section when said accommodation groove and said positioning groove meet each other.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] FIG. 1 is a schematic view showing a conventional magnetic screwdriver;
[0016] FIG. 2 is a schematic view showing an operation of the conventional magnetic screwdriver;
[0017] FIG. 3 is a schematic view showing a first preferred embodiment of this invention;
[0018] FIG. 4 is a schematic view showing an operation of the first preferred embodiment of this invention;
[0019] FIG. 5 is a schematic view showing that the sleeve member is detached from the second section;
[0020] FIG. 6 is a schematic view showing that the screwdriver is adapted to rotate the screw head into an object provided with a pre-drilled opening;
[0021] FIG. 7 is a schematic view showing a second preferred embodiment of this invention characterized by the cover unit;
[0022] FIG. 8 is a schematic view showing an operation of the second preferred embodiment of this invention; and
[0023] FIG. 9 is a schematic view showing that the sleeve member is detached from the second section.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0024] Referring to FIG. 3, a first preferred embodiment of a screwdriver 4 is disclosed. The screwdriver 4 is driven by a driving tool (not shown) and adapted to engage with a socket 51 of a screw head 5 in order to drive the screw head 5 to execute a screwing operation. The screwdriver 4 in this preferred embodiment comprises a first section 41 adapted to engage with the driving tool, a second section 42 connected to the first section 41 and adapted to engage with the socket 51 of the screw head 5, a sleeve member 43 sleevedly disposed on an outer periphery of the second section 42 and capable of being separated from the second section 42, and an engagement member 44 disposed in the sleeve member 43 and adapted to fix the sleeve member 43 to the second section 42. A positioning groove 421 is annularly recessed into the outer periphery of the second section 42. A type of the second section 42 is corresponding to a type of the socket 51 of the screw head 5. The type of the second section 42 is formed into a cruciform type, a square type, a hexalobular type or other polygonal types. Here takes an example that the second section 42 is a hexalobular type which is commonly known as a Torx type.
[0025] Referring to FIG. 3 and FIG. 4, the sleeve member 43 has a body 431 defining a top end 431A and a bottom end 431B, a through hole 432 penetrating through the body 431 for defining an inner peripheral wall 431C between the top end 431A and the bottom end 431B, a magnetic unit 433 disposed in the through hole 432 and located opposite to the top end 431A, and an accommodation groove 434 recessed into the inner peripheral wall 431C and formed opposite to the bottom end 431B. The engagement member 44 is disposed in the accommodation groove 434.
[0026] When the second section 42 passes through the through hole 432 of the sleeve member 43 to position the sleeve member 43 properly on the second section 42, the accommodation groove 434 and the positioning groove 421 are located in correspondence and aligned with each other to thereby restrict the engagement member 44 between the accommodation groove 434 and the positioning groove 421 and position the sleeve member 43 in the middle of the second section 42. Thus, a firm engagement between the sleeve member 43 and the second section 42 is achieved. When the second section 42 is engaged with the socket 51 of the screw head 5, the bottom end 431B of the body 431 is adjacent to but not in contact with a top surface 52 of the screw head 5 to thereby form a gap D between the top surface 51 and the bottom end 431B. The gap D ranges from 2 mm to 3 mm.
[0027] Referring to FIG. 4 and FIG. 5, an installation of the screwdriver 4 is executed by inserting the second section 42 through the through hole 432 of the sleeve member 43 until the accommodation groove 434 and the positioning groove 421 face each other to thereby engage the engagement member 44 with the positioning groove 421. Thus, the sleeve member 43 is positioned in the middle of the second section 42. After that, the second section 42 is inserted into the socket 51 of the screw head 5 to form the gap D between the bottom end 431B of the sleeve member 43 and the top surface 52 of the screw head 5, so the magnetic unit 433 attracts the screw head 5 though the magnetic force without being in contact with the screw head 5 whereby the screw head 5 is positioned stably and properly. Further, the magnetic attraction between the magnetic unit 433 and the screw head 5 can help guide and straighten the screw head 5. After the screw head 5 is straightened by the screwdriver 4, a rotational force is applied on the screwdriver 4 to further rotate the screw head 5 into an object 6 quickly and stably until the screw head 5 enters into the object 6 entirely to achieve a tight engagement between the screw head 5 and the object 6. Finally, the second section 42 of the screwdriver 4 is removed from the socket 51 of the screw head 5 whereby the screwing operation of the screw head 5 is completed.
[0028] After the sleeve member 43 is properly engaged with the second section 42, the sleeve member 43 is positioned in the middle of the second section 42 stably. Hence, the bottom end 431B of the sleeve member 43 is spaced apart from the top surface 52 of the screw head 5 to form the gap D after the second section 42 is inserted into the socket 51 of the screw head 5. Thus, the gap D helps prevent metal chips or powders caused during the screwing operation from adhering to the magnetic unit 433 while the magnetic attraction is still maintained. Meanwhile, the gap D also prevents the top surface 52 of the screw head 5 from being rubbed unduly by the sleeve member 43. If the metal chips or powders enter into the through hole 432, the metal chips or powders can be cleaned easily by detaching the sleeve member 43 from the second section 42 as shown in FIG. 5. After the metal chips or powders in the through hole 432 are removed, the second section 42 is inserted into the sleeve member 43 through the through hole 432 until the engagement member 44 is engaged with the positioning groove 421 whereby the sleeve member 43 is properly engaged with the second section 42 and the screwdriver 4 can be used again.
[0029] Referring to FIG. 6 shows the object 6 is provided with a pre-drilled opening 61. After the second section 42 is positioned in the socket 51 of the screw head 5, the screwdriver 4 can drive the screw head 5 to screw into the opening 61 of the object 6 without being hindered by the sleeve member 43. Because the sleeve member 43 is not in contact with the top surface 52 of the screw head 5 to form the gap D when the second section 42 is inserted into the socket 51 of the screw head 5, the sleeve member 43 will not contact and press the object 6 to further allow the second section 42 to screw the screw head 5 deeply into the opening 61. Meanwhile, the screwing operation of the screw head 5 can be completed in one time and no additional tool is required. Further, the opening 61 will not be damaged by the screwdriver 4. The screwing operation of the screw head 5 can be executed smoothly to thereby attain the speedy and steady screwing effect. In order to drive the screw head 5 provided with different types of sockets 51, the sleeve member 43 can be separated from the second section 42 and detachably disposed on another second section 42 having the type in correspondence with the socket 51 of the screw head 5. Hence, the user's burden is lightened by bringing only one sleeve member 43 and different second sections 42. Further, when the sleeve member 43 is worn or damaged, the second section 42 can be still kept to be used with other sleeve member 43. Alternatively, when the second section 42 is worn or damaged, the sleeve member 43 can be kept to be used with other second section 42 to thereby reduce the cost and increase the convenience of use.
[0030] Referring to FIG. 7 and FIG. 8 show a second preferred embodiment of the screwdriver 4 of this invention. The correlated elements and the concatenation of elements, the operation and objectives of the second preferred embodiment are the same as those of the first preferred embodiment. This embodiment is characterized in that a cover unit 435 extends outwards from the bottom end 431B of the sleeve member 43 and defines a room 435C communicating with the through hole 432. The cover unit 435 has a lower end 435A and an upper end 435B. The upper end 435B is connected to the bottom end 431B of the sleeve member 43. An inner diameter R1 of the lower end 435A is larger than an inner diameter R2 of the upper end 435B. The inner diameter R1 of the lower end 435A is also larger than a diameter R3 of the through hole 432 of the sleeve member 43. In this preferred embodiment, the inner diameter R1, as for instance shown in FIG. 7, can be deemed to be a maximum diameter of the room 435C of the cover unit 435. The lower end 435A of the cover unit 435 and an end surface 422 of the second section 42 are aligned horizontally when the sleeve member 43 is positioned properly on the second section 42. In other words, the lower end 435A of the cover unit 435 and the end surface 422 of the second section 42 are located at the same horizontal line L when the sleeve member 43 is properly engaged with the second section 42. Thus, when the second section 42 is placed in the socket 51 of the screw head 5, the lower end 435A will not contact the top surface 52 of the screw head 5 but surround the screw head 5 to thereby retain the metal chips or powders within the room 435C of the cover unit 435 and prevent the metal chips or powders from spurting or hurting the user during the screwing operation. Simultaneously, the magnetic unit 433 can still attract the screw head 5 without contacting the screw head 5. After the screwing operation of the screw head 5 is completed, the metal chips or powders remained in the through hole 432 and the room 435C of the cover unit 435 can be cleaned easily by removing the sleeve member 43 from the second section 42 and cleaning the through hole 432 and the room 435C thereafter as shown in FIG. 9 to thereby improve the magnetic effect of the sleeve member 43 and improve the smoothness and the screwing effect of the screwing operation effectively.
[0031] To sum up, the screwdriver of this invention takes advantages that the engagement member is engaged with the positioning groove of the second section to position the sleeve member on the second section properly. When the second section is inserted into the socket of the screw, the bottom end of the sleeve member is spaced apart from the top surface of the screw head to form the gap whereby the magnetic unit can attract the screw head without being in contact with the screw head. Thus, the sleeve member can position and guide the screw head through the magnetic attraction to thereby accelerate the screwing operation of the screw head and attain the stable screwing effect. Further, the metal chips or powders caused during the screwing operation can be cleaned easily by detaching the sleeve member from the second section and cleaning the through hole thereafter to thereby improve the magnetic effect of the sleeve member and extend the service life of the sleeve member.
[0032] While the embodiments of this invention are shown and described, it is understood that further variations and modifications may be made without departing from the scope of this invention.
