JP3206871U - Drill screw - Google Patents

Abstract

To provide a drill screw capable of achieving quick screw coupling during use and reducing screw coupling torque by smoothly guiding chips and enhancing the chip accommodation effect. A drill unit includes a drill body 341 following a threaded portion 32, an end surface 342 at the tip of the drill body 341, and two chip guides that are engraved in the drill body 341 to divide the end surface 342 into two sides. A groove 343, a drill blade 344 formed at a position where each part of the end surface 342 and the chip guide groove 343 are connected, and a stereotaxic end 345 formed by connecting the tips of the two drill blades 344, and a chip guide The groove 343 has a cutting blade 348 that is formed at a position where the continuous locking surface 346 and the flat surface 347 and the flat surface 347 and the surface of the drill body 341 are connected to each other and is continuous from the drill blade 344, An arc surface 349 is formed, and the depressed arc surface 349 is formed across the end surface 342, the flat surface 347, and the stereotaxic end 345. [Selection] Figure 3

Description

  The present invention relates to a drill screw.

As shown in FIGS. 1 and 2, a conventional drill screw 1 includes a screw head 11, a screw portion 12 extending outward from the screw head 11, and a plurality of threads 13 installed in a spiral on the screw portion 12. And a drill unit 14 installed on the screw portion 12 on the side opposite to the screw head 11.
The drill unit 14 includes a drill body 141 following the threaded portion 12, an end surface 142 formed at the end of the drill body 141, a chip that is engraved on the drill body 141 and divides the end surface 142 into two corresponding sides. It has a guide groove 143, two drill blades 144 formed at a position where each end face 142 and each chip guide groove 143 are connected, and a stereotaxic end 145 formed at a position where the two drill blades 144 are connected.
A locking surface 146, a flat surface 147, and a cutting blade 148 are formed at positions where each chip guide groove 143 and the drill body 141 are connected.

At the time of screw connection, the stereotaxic end 145 is pressed against the object 2 and a rotational force is applied, so that the two drill blades 144 first drill holes and guide the drill body 141 into the object 2.
Chips generated in the drilling process are discharged out of the respective chip guide grooves 143, thus completing the screw coupling operation.

In the above-described conventional structure, since the chip guide groove 143 is opened on the drill body 141, the end surface 142 and the chip guide groove 143 are not connected.
Therefore, the chips fit into the end surface 142 and receive downward pressure, and are blocked by the locking surface 146, and cannot enter the chip guide groove 143 smoothly.
As a result, the drill resistance of the two drill blades 144 increases, leading to a reduction in cutting speed.
Therefore, unless the user applies a larger rotational force, the cutting blade 148 cannot enter the property 2.
However, if such an operation is performed, the drill blade 144 is likely to be worn away, which adversely affects the progress of the initial screw coupling operation.

Furthermore, in order to reinforce the drill strength of the drill unit 14, heat treatment is generally performed during the molding process of the drill unit 14.
However, the processing method is that the drill unit 14 is excessively hardened, so that each of the drill blades 144 is hardened but becomes brittle, cannot effectively resist the screw coupling stress, and breaks and breaks at the initial stage of drill cutting. The phenomenon will occur.
This affects the drill cutting ability subsequent to the drill screw 1 and further reduces the screw coupling speed.

That is, the conventional drill screw described above has a drawback that the drill blade is easily worn away, adversely affects the progress of the initial screw coupling operation, and breakage and tearing occur at the initial stage of drill cutting.
The problem to be solved by the present invention is to solve the above-mentioned problems, to achieve a quick screw connection at the time of use and to reduce the screw connection torque by guiding the chips smoothly and enhancing the chip accommodation effect. It is to provide a drill screw that can be used.

  The drill screw of the present invention includes a screw head, a screw portion extending from the screw head, a plurality of threads spirally installed on an outer peripheral surface of the screw portion, and the screw on the side opposite to the screw head. A drill unit that is provided at a point, and the drill unit includes a drill body that follows the threaded portion, an end surface that is formed at a tip of the drill body, and a peripheral surface to an end surface of the drill body. Two drill guide grooves that are provided, and that divide the end face into two sides, two drill blades that are respectively formed at positions where the divided parts of the end face are connected to the respective chip guide grooves, And a fixed end formed at a position where the tips of the two drill blades are connected to each other, and each of the chip guide grooves has a locking surface as one side surface of the chip guide groove, Continued, the other side of the chip guide groove And a plane where the plane and the surface of the drill body are connected to each other, a cutting blade continuous from the drill blade, and a concave arc surface formed on each locking surface, and the depression The arc surface extends from the end surface over the plane and simultaneously extends further downward to be connected to the stereotaxic end.

Each of the end faces is composed of a first and a second inclined section, the first inclined section is connected to the drill body, the second inclined section extends from the first inclined section to a stereotaxic end, A depression angle formed by intersecting lines along the drill blade formed at positions where the first inclined sections on the both end faces and the chip guide groove are connected to each other is the second inclined section on the both end faces and the chip guide. The lines along the drill blades formed at the positions where the grooves are connected to each other may be larger than the depression angle formed by intersecting.
Each cutting blade may be inclined so as to gradually approach the central axis from each drill blade toward the threaded portion, and the maximum distance from each drill blade to the central axis may be larger than the radius of the threaded portion.

  According to the present invention, a large amount of chips generated at the time of drill cutting are not obstructed by using the depressed arc surface formed on the locking surface, and enter the chip guide groove through the end surface and the depressed arc surface. Proceeding quickly and quickly expelling to the outside. As a result, it is possible to avoid an increase in the resistance force applied to each drill blade by being obstructed by excessively accumulated chips, and a quick screw connection can be performed.

It is a side view of the conventional drill screw. It is sectional drawing in the screw connection state of the conventional drill screw. 1 is a perspective view of a drill screw showing a first embodiment of the present invention. It is a principal part enlarged view of FIG. It is sectional drawing in the screwed state of the drill screw which shows the 1st Example of this invention. It is a principal part side view of the drill screw which shows the 2nd Example of this invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
3 to 5 show a first embodiment of the present invention.
As shown in FIGS. 3 and 4, the drill screw 3 of the first embodiment includes a screw head 31, a screw portion 32 extending from the screw head 31, and a plurality of spiral screws installed on the outer peripheral surface of the screw portion 32. On the opposite side of the thread 33 and the screw head 31, there is a sharp drill unit 34 that is continuously installed on the screw portion 32.

  The drill unit 34 includes a drill body 341 following the threaded portion 32, an end surface 342 formed at the tip of the drill body 341, and engraved from the peripheral surface to the end surface of the drill body 341, and the end surface 342 is divided into two sides. Two drill guide grooves 343, two drill blades 344 formed at positions where each divided portion of the end surface 342 and each chip guide groove 343 are connected, and tips of the two drill blades 344 It has a stereotaxic end 345 that is formed in a flat shape.

Each chip guide groove 343 includes a locking surface 346 serving as one side surface of the chip guide groove 343, a flat surface 347 serving as the other side surface of the chip guide groove 343, and a flat surface 347 and a drill. A cutting blade 348 is formed at a position connected to the surface of the body 341 and is continuous from the drill blade 344.
In this embodiment, two drill blades 344 are arranged on both sides of the center of one diameter in the cross section of the drill body 34 (see FIG. 5).
The stereotaxic end 345 has a protruding pointed shape, and lines along the two drill blades 344 intersect to form a depression angle α.

A depression arc surface 349 is formed on the locking surface 346, and the depression arc surface 349 extends from the end surface 342 to the position of the plane 347.
As shown in FIG. 4, the depressed arc surface 349 extends from a position where the end surface 342 and the locking surface 346 are connected to a position where the locking surface 346 and the flat surface 347 are connected.
At the same time, the depressed arc surface 349 extends further downward and is connected to the stereotaxic end 345, thus improving the smoothness of the chip guide and expanding the entire space of each chip guide groove 343.

As shown in FIG. 5, when performing the screw connection work, first, the localization end 345 is fitted on the screw connection object 4.
Since the stereotaxic end 345 has a protruding pointed shape, when it is pressed against the threaded article 4, it forms a firm stereotaxic position and does not cause a displacement sliding phenomenon.
Then, using a screw coupling tool (not shown), rotational torque is applied to the screw head 31 to rotate the two drill blades 344 in conjunction with each other to perform drill cutting, and gradually into the screw coupling article 4. Screw in.
The cutting blade 348 of the drill body 341 performs drill cutting following each drill blade 344, and thus a plurality of chips are generated.

At this time, since the depression arc surface 349 is formed between the end surface 342 and the chip guide groove 343, the chips generated during the drill cutting of each drill blade 344 first enter each depression arc surface 349. Is not subjected to the pressing of the end surface 342 and is not affected by the locking surface 346.
At the same time, the chips formed by the drilling of the cutting blade 348 are also guided effectively and quickly into the chip guide groove 343.
In this way, the chips cut by each drill blade 344 and cutting blade 348 are quickly discharged to the outside through the chip guide groove 343, and the cutting resistance force of each drill blade 344 and cutting blade 348 is greatly reduced.

Furthermore, the depressed arc surface 349 formed on the locking surface 346 extends between the end surface 342, the flat surface 347, and the stereotaxic end 345.
Therefore, since the end surface 342 communicates with the flat surface 347 via the depression arc surface 349, not only the smoothness of the chip guide can be improved, but also the chip accommodating space of each chip guide groove 343 can be further expanded, Some chips can be kept in a safe space.
Therefore, at the initial stage of drill cutting, the drill unit 34 utilizes the recessed arc surface 349 to enhance the chip accommodation effect, achieve the best and quick cutting effect, effectively increase the screw coupling torque, The coupling efficiency can be improved.

FIG. 6 shows a second embodiment of the present invention.
In the second embodiment, the description of the same structure as that of the first embodiment is omitted.
In the present embodiment, each end surface 342 of the drill unit 34 includes a first and second inclined sections 3421 and 3422.
The first inclined section 3421 is connected to the drill body 341, and the second inclined section 3422 extends from the first inclined section 3421 to the stereotaxic end 345.
At the same time, the depression angle α1 formed by intersecting the lines along the drill blade 344 formed at the position where the first inclined section 3421 of each end surface 342 and each chip guide groove 343 are connected is the second angle α1 of each end surface 342. A line along the drill blade 344 formed at a position where the inclined section 3422 and each chip guide groove 343 are connected is larger than a depression angle α2 formed by intersecting.
As a result, the end face 342 is coupled to the stereotaxic end 345 and has a two-section structure as a whole, and has a pointed structure protruding outward.

Furthermore, in this embodiment, each cutting blade 348 can be inclined so as to gradually approach the central axis as it goes from each drill blade 344 toward the screw portion 32.
At the same time, the maximum distance from the outer edge of each drill blade 344 to the central axis is larger than the radius of the threaded portion 32 (the radius of the portion excluding the thread 33). In the present embodiment, since the two drill blades 344 are arranged on both sides sandwiching the center of one diameter, the maximum outer diameter r2 between the outer edges of the two drill blades 344 is equal to the screw portion 32. It is larger than the outer diameter r1.
That is, the position where each drill blade 344 and each cutting blade 348 are connected forms a maximum outer diameter r 2, and the maximum outer diameter r 2 is larger than the outer diameter r 1 of the screw portion 32.

At the time of screw connection, a special pointed design formed on the stereotaxic end 345 is used to form a stereotaxic action that does not shift initially.
When two drill blades 344 enter the threaded article, the maximum outer diameter r2 is larger than the outer diameter r1, and the two drill blades 344 are pressed onto the threaded article 4, so that two The drill blade 344 and the localization end 345 form a three-point support localization effect.
Thereby, when the stereotaxic end 345 and the two drill blades 344 perform the drill cutting, the drill stress can be effectively resisted, and the state of tearing does not occur, and the quick drill cutting of the drill body 341 is interlocked. Can do.
At the same time, the installation of the recessed arc surface 349 allows the chips to enter the chip guide groove 343 without being disturbed and to be discharged to the outside, thus increasing the screw coupling speed and the tight fixing force of the drill screw 3.

In summary, the drill screw of the present invention expands the chip guide space by the recessed arc surface formed on the locking surface of the drill unit, and the influence of the chips on the drill speed due to the blockage of the locking surface. Can be avoided.
Therefore, not only can the smoothness of the chip guidance be effectively increased, but also the chip containment effect is greatly enhanced by the recessed arc surface, and the screw coupling torque is reduced due to the inhibition of chips that accumulate too much each drill blade. Can be avoided.
In this way, effects such as quick screw connection can be achieved.

  The above is an explanation of the embodiments of the present invention, and does not limit the scope of rights of the present invention. Any changes or modifications that do not depart from the scope of the utility model registration request of the present invention are within the scope of rights of the present invention. included.

DESCRIPTION OF SYMBOLS 1 Drill screw 11 Screw head 12 Thread part 13 Thread 14 Drill unit 141 Drill body 142 End surface 143 Chip guide groove 144 Drill blade 145 Orientation end 146 Locking surface 147 Planar 148 Cutting blade 2 Property 3 Drill screw 31 Screw head 32 Threaded portion 33 Thread 34 Drill unit 341 Drill body 342 End surface 343 Chip guide groove 344 Drill blade 345 Positioning end 346 Locking surface 347 Flat surface 348 Cutting blade 349 Depressed arc surface 3421 First inclined section 3422 Second inclined section α Fixed end angle α1 Angle of inclination of the first inclined section α2 Angle of depression of the second inclined section r1 Outer diameter of the threaded portion r2 Maximum outer diameter of the drill blade 4 Screw connection

Claims (3)

A drill screw, a screw head, a screw portion extending from the screw head, a plurality of threads spirally installed on an outer peripheral surface of the screw portion, and the screw on the opposite side of the screw head Has a sharp drill unit installed continuously in the part,
The drill unit includes a drill body following the threaded portion, an end surface formed at a tip of the drill body, an engraved portion extending from the peripheral surface to the end surface of the drill body, and dividing the end surface into two sides. Each chip guide groove, two drill blades formed at a position where each of the divided portions of the end face and each chip guide groove are connected, and a position where the tips of the two drill blades are connected Having a stereotaxic end,
Each of the chip guide grooves includes a locking surface serving as one side surface of the chip guide groove, a plane following the locking surface and serving as the other side surface of the chip guide groove, and the plane and the drill body. Is formed at a position connected to the surface of the drill, and has a cutting blade continuous from the drill blade,
A concave arc surface is formed on each locking surface, and the concave arc surface extends from the end surface over the plane, and further extends downward to be connected to the stereotaxic end. Drill screw to do. Each of the end faces is composed of a first and a second inclined section,
The first inclined section is connected to the drill body;
The second inclined section extends from the first inclined section to the stereotaxic end,
The depression angle formed by intersecting the lines along the drill blade formed at the positions where the first inclined sections on both end faces and the chip guide grooves are connected to each other is the second inclined section on the both end faces and each cutting edge. The drill screw according to claim 1, wherein a line along the drill blade formed at a position where the scrap guide groove is connected to each other is larger than a depression angle formed by intersecting. Each of the cutting blades is inclined so as to gradually approach the central axis as it goes from the drill blades to the threaded portion,
The drill screw according to claim 1 or 2, wherein a maximum distance from an outer edge of each drill blade to a central axis is larger than a radius of the thread portion.

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