TWM449048U - Drill structure - Google Patents

Abstract

A drill structure is provided here. The drill structure comprises a handle and a cutting section. The cutting section is connected to the handle and there are two helical flutes arranged on the cutting section. Two helical flutes alternatively extend from a drill tip to the handle. There is at least a variable-pitch part formed on the cutting section, wherein the distance between the first helical flute and the second helical flute is different. By adjusting the distance between two helical flutes, the drill structure can better satisfy users' different requirements. Entire strength of the drill structure increases and ability of chip removal is improved. As a result, there is better performance for drilling holes.

Description

Drill structure

The present invention relates to a drill bit structure, and more particularly to a drill bit structure having a partial chip discharge groove with a partial groove gradient.

The high-density and high-precision line refinement of electronic circuits on printed circuit boards has led to the extensive use of ultra-small-diameter drill bits in the drilling process, and the market is competing for high quality, high demand and rapid supply of printed circuit boards. It is a common expectation and demand to require the drill to achieve high precision, high feed rate, good hole wall quality and unbroken machining conditions in the operation; in order to improve work efficiency and reduce manufacturing costs, on the printed circuit board Through-hole drilling is the process of drilling a number of overlapping printed circuit boards for through-hole drilling, so the longer the drill bit is used, the drill bit needs to have sufficient strength and fast chip removal.

The two cutting edges of the conventional drill bit are mostly provided with a spiral chip discharge groove along the axial direction of the drill bit to discharge the waste cutting edge of the blade along the chip discharge groove, as shown in Fig. 1 as a part of a conventional drill bit. Schematically, as shown, the drill bit structure 100 includes a shank portion 110 and a drill edge portion 120. The two chip discharge grooves G1 and G2 formed on the surface of the drill blade portion 120 are interlaced spirally arranged symmetrically, and the groove distances of the two chip discharge grooves G1 and G2 are equidistant, and cannot be based on the amount of waste discharged. Adjusting the groove distance of the chip discharge groove, this may affect the smoothness of the chip removal, and further cause the chip to block between the drill blade portion 120 and the hole wall during the drilling process, thereby affecting the quality of the hole wall.

On the other hand, if the pitches of the two spiral-shaped chip discharge grooves G1 and G2 looped on the drill blade portion 120 are all equidistant and cannot be adjusted, the overall structural strength of the drill bit structure 100 may be affected, for example, the chip discharge groove. Excessively high density results in insufficient strength, which causes the cutting edge portion 120 to accelerate wear and damage at high speeds, causing needle breakage problems.

In order to solve the above problems, one of the purposes of the present invention is to provide a drill bit structure, which can increase the variability of the chip discharge groove of the drill bit structure by adjusting the groove distance of the two chip discharge grooves, improve the overall rigidity of the drill bit, and increase the chip space. And the chip removal force, thereby improving the accuracy of the drilling to have better drilling performance.

In order to achieve the above object, a bit structure of an embodiment of the present invention includes a shank portion and a drill edge portion. The drill blade portion is connected to the shank portion, the surface of the drill blade portion is spirally disposed with a first chip discharge groove and a second chip discharge groove, and the first chip discharge groove and the second chip discharge groove are staggered by a drill tip toward the shank portion Extending, and the cutting edge portion comprises at least one variable pitch segment, wherein a distance between the first chip discharge groove and the second chip discharge groove in the variable distance segment is gradually changed.

In the following, the specific embodiments and the accompanying drawings are explained in detail, and it is easier to understand the purpose, technical content, characteristics and effects achieved by the present invention.

2 is a partial cross-sectional view showing the structure of the drill bit according to an embodiment of the present invention. As shown, the drill bit structure 200 includes a drill shank portion 210 and a drill edge portion 220. The drill blade portion 220 is connected to the shank portion 210, and a first chip discharge groove V1 and a second chip discharge groove V2 are spirally disposed. The first chip discharge groove V1 and the second chip discharge groove V2 are oriented by a drill tip 221 The shank portion 210 extends in a staggered manner, and the cutting edge portion 220 includes at least one variable pitch portion 223, wherein the first chip discharge groove V1 and the second chip discharge groove V2 are gradually tapered by the groove distance Dv of the variable pitch portion 223. In addition, in addition to the variable pitch section 223, the cutting edge portion 220 may further include an equidistant section 222 in which the groove distance Dv of the first chip discharge groove V1 and the second chip discharge groove V2 on the equidistant section remains unchanged. In other words, under the premise that the cutting edge portion 220 is provided with at least one variable pitch segment, the number of the variable pitch segment and the equidistant segment is not limited, and can be freely arranged.

Referring to FIG. 2 again, in an embodiment, the drill portion 220 of the drill bit structure 200 has an equidistant section 222 and a variable pitch section 223, wherein the first chip discharge groove V1 and the second chip discharge groove V2 are equal. The groove distance Dv from the segment 222 remains unchanged. When the first chip discharge groove V1 and the second chip discharge groove V2 extend to the variable pitch section 223, the groove distance Dv starts to gradually widen toward the shank portion 210. In this embodiment, the equidistant section 222 has a narrower and fixed pitch Dv because the equidistant section 222 is the front section of the drill bit structure 200, that is, adjacent to the drill tip 221, which directly cuts the workpiece and produces a large amount of chips. Therefore, a denser groove is required to discharge the chips and make the drilling process smooth. The variable distance section 223 is located at the rear of the drill bit structure 200, that is, adjacent to the shank portion 210, and has less influence on the chip discharge, thereby gradually widening the groove distance Dv, reducing the density of the groove, and strengthening the structural strength of the drill bit structure 200. To avoid damage. In this way, the design of the variable pitch of the creation groove can be considered according to the user's consideration, taking into account the effect of chip discharge and the physical strength of the bit structure.

Please refer to FIG. 3. FIG. 3 is a partial cross-sectional view showing the structure of the drill bit according to another embodiment of the present invention. Here, the drill portion 320 of the drill bit structure 300 has an equidistant section 322, a variable pitch section 323, and another equidistant section 324, that is, the equidistant sections 322, 324 and the variable pitch section 323 are staggered. The groove distance Dv' of the first chip discharge groove V1' and the second chip discharge groove V2' on the equidistant section 322 remains unchanged. When the first chip discharge groove V1' and the second chip discharge groove V2' extend to the variable pitch section 323, the groove distance Dv' starts to gradually widen toward the shank portion 210. Next, when the first chip discharge groove V1' and the second chip discharge groove V2' extend to the equidistant section 324, the groove distance Dv' remains unchanged. It can be seen that Dv' is narrower and denser in the equidistant section 322, wider in the variable pitch section 323, and wider in the equidistant section 324. The design of the creation of the groove distance can also take into account the effect of chip discharge and the physical strength of the bit structure. The principle has been detailed in the foregoing, and will not be described here.

In addition, there are several ways to form a variable pitch section in the drill edge portion, one of which is by changing the spiral inclination angle. For example, as shown in FIG. 2, the first chip discharge groove V1 and the second chip discharge groove V2 have a first spiral inclination angle A1 and a second spiral inclination angle A2, respectively. The first helix angle A1 maintains the same angle at the equidistant section 222, so the pitch Dv is equidistant. However, when the first chip discharge groove V1 continues to extend to the variable pitch section 223, the first spiral inclination angle A1 gradually decreases, and the groove distance Dv thus gradually increases. Moreover, the manner in which the first spiral inclination angle A1 and the second spiral inclination angle A2 are changed is not particularly limited, and both may be changed, or one may be fixed, one may be changed, and the angle change rates of the two may be the same or different. When the spiral inclination angle is changed, the stepless progressive design can be adopted, that is, the change of the spiral inclination angle is a gradual change, instead of simply turning from one angle of the spiral inclination angle to another angle.

In addition to changing the pitch, it is also possible to additionally adjust the depth H of the chip discharge groove (H as shown in Fig. 2). In one embodiment, the first chip discharge groove and the second chip discharge groove are both deep-graded structures (not shown). In still another embodiment, the depths of the first chip discharge groove and the second chip discharge groove are the same or different (not shown).

In the present creation, under the premise that the drill edge portion of the drill bit structure has at least one variable pitch segment, the number and arrangement of the variable pitch segment and the equidistant segment are not limited. There are many ways to create a variable pitch segment, one of which is to change the helix angle. The manner of the change is also not particularly limited, that is, the first helix angle and the second helix angle can be changed simultaneously, or one is fixed and the other is changed. In addition, the depth of the chip discharge groove can also be adjusted.

In the present invention, by adjusting the groove distance of the second chip discharge groove in the drill edge portion, the variability of the chip discharge groove of the drill bit structure is increased, the overall rigidity of the drill bit is improved, and the chip space and the chip removal force are increased, thereby obtaining Better drilling performance.

The embodiments described above are only for explaining the technical idea and characteristics of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement them according to the scope of the patent. That is, the equivalent changes or modifications made by the people in accordance with the spirit revealed by this creation should still be covered by the scope of the patent of this creation.

100, 200, 300‧‧‧ drill structure

110, 210, 310‧‧‧ drill handle

120, 220, 320‧‧‧Drilling

221, 321‧‧‧ drill tip

222, 322, 324‧‧‧ equidistant segments

223, 323‧‧ ‧ variable distance

A1‧‧‧first spiral angle

A2‧‧‧second spiral angle

Dv, Dv’‧‧‧

H‧‧‧ Depth

G1, V1, V1'‧‧‧ first chip discharge ditch

G2, V2, V2'‧‧‧Second chip discharge ditch

Figure 1 is a partial cross-sectional view showing a conventional drill bit structure.

2 is a partial cross-sectional view showing the structure of a drill bit according to an embodiment of the present invention.

3 is a partial cross-sectional view showing the structure of a drill bit according to another embodiment of the present invention.

200‧‧‧ drill structure

210‧‧‧Drilling handle

220‧‧‧Drilling

221‧‧‧ drill tip

222‧‧‧ equidistant segments

223‧‧‧ variable distance

A1‧‧‧first spiral angle

A2‧‧‧second spiral angle

H‧‧‧ Depth

Dv‧‧‧ditch

V1‧‧‧first chip discharge ditch

V2‧‧‧Second chip discharge ditch

Claims (10)

A drill bit structure comprising: a drill handle portion; and a drill blade portion connecting the drill handle portion, wherein a surface of one of the drill handle portions is spirally disposed with a first chip discharge groove and a second chip discharge groove, the first The chip discharge groove and the second chip discharge groove are staggered from a drill tip toward the shank portion, and the drill blade portion includes at least one variable pitch segment, wherein the first chip discharge groove and the second chip discharge groove The pitch of the variable pitch segment is gradually changed. The bit structure of claim 1, wherein the cutting edge portion comprises at least one equidistant segment, wherein the first chip discharge groove and the second chip discharge groove have a constant groove distance on the equidistant segments. The bit structure of claim 2, wherein the order of the variable pitch segments and the equidistant segments of the drill edge portion are freely arranged. The bit structure of claim 2, wherein the equidistant segment is adjacent the drill tip, the variable pitch segment being adjacent the shank portion. The drill bit structure of claim 1, wherein the drill cutting portion comprises a plurality of equidistant segments and a plurality of the variable pitch segments, and the equidistant segments and the variable pitch segments are staggered. The drill bit structure of claim 1, wherein the first chip discharge groove and the second chip discharge groove respectively have a first spiral inclination angle and a second spiral inclination angle, wherein the first spiral inclination angle and the second The change of at least one of the inclination angles of the spiral causes the first chip discharge groove and the second chip discharge groove to gradually change the groove distance of the variable distance section. The bit structure of claim 6, wherein one of the first helix angle and the second helix angle is fixed. The drill bit structure of claim 6, wherein the first spiral inclination angle and the second spiral inclination angle have the same or different angular change rates. The drill bit structure of claim 1, wherein the first chip discharge groove and the second chip discharge groove are both deep-graded structures. The drill bit structure of claim 1, wherein the first chip discharge groove and the second chip discharge groove have the same or different depths.