CN219598181U

CN219598181U - Drilling tool

Info

Publication number: CN219598181U
Application number: CN202320075637.1U
Authority: CN
Inventors: 朱水生; 刘绪维; 王正齐; 薛翔远; 王威
Original assignee: Guangdong Dingtai Hi Tech Co ltd
Current assignee: Guangdong Dingtai Hi Tech Co ltd
Priority date: 2023-01-10
Filing date: 2023-01-10
Publication date: 2023-08-29
Anticipated expiration: 2033-01-10

Abstract

The utility model provides a drilling tool, which comprises a tool body and a tool tip structure arranged at one end of the tool body. The cutter body is provided with a main chip removal groove and an auxiliary chip removal groove; the tool tip structure comprises first to second main rear tool faces and first to second auxiliary rear tool faces, the first main rear tool face is intersected with the second auxiliary rear tool faces to define a main chisel edge, the second main rear tool face is intersected with the first auxiliary rear tool faces to define auxiliary chisel edges, the second auxiliary rear tool faces are intersected with the side faces of the tool body to define rear side edges, the side faces of the tool body are intersected with the first main rear tool faces and the second main rear tool faces at the same time to define towel backs, the groove side wall surfaces of the main chip grooves are intersected with the first main rear tool faces to define main cutting edges, and the groove side wall surfaces of the auxiliary chip grooves are intersected with the first auxiliary rear tool faces to define auxiliary cutting edges; the maximum size of the auxiliary chip groove is 1.05 to 2.3 times that of the main chip groove, and the length of the auxiliary chisel edge is 0.15 to 0.7 times that of the main chisel edge; so as to improve heat dissipation and hole wall quality.

Description

Drilling tool

Technical Field

The utility model relates to the technical field of drilling processing, in particular to a drilling tool.

Background

With the continuous development of electronic products, people have increasingly high requirements on the quality and reliability of the electronic products. As the PCB of the important components of the electronic product, the requirements on hole position precision and hole wall quality are continuously improved during the drilling of the PCB, so that the requirements on the drill bit are also higher and higher.

In the drill disclosed in chinese patent application No. 200510105356.2, a single-edge cutting structure with two chip grooves non-centrally symmetrical with respect to the rotation center is adopted, so that the rigidity of the drill can be increased, and the drilling precision is improved, however, in the practical application process, the intersecting line of the auxiliary chip groove of the structure and the first auxiliary rear tool face also wears, which means that the auxiliary cutting edge also participates in cutting in the practical use. Because the cutting rake angle of the secondary cutting edge is larger than that of the main cutting edge, the service condition of the drill bit is deteriorated, and the improvement of drilling quality and stability is not facilitated.

In addition, the direct contact of the secondary cutting edge and the workpiece also generates additional heat, and is unfavorable for heat dissipation and improvement of hole wall quality.

Moreover, the width of the rear side edge is small by the method of offsetting the chip grooves, so that the width of the towel back is large, the towel back and the waste are mutually restricted, the contact area with the hole wall cannot be effectively reduced, the hole wall is rough, and the friction heat is large.

Accordingly, there is a need for improvements in single-edged drill bits for PCBs that provide a drilling tool that overcomes one or more of the above-described deficiencies.

Disclosure of Invention

The utility model aims to provide a drilling tool which can prevent a secondary cutting edge from contacting with a workpiece during actual processing, reduce the contact area with a hole wall and improve the drilling precision and the hole wall quality.

In order to achieve the above object, the drilling tool of the present utility model includes a cutter body and a nose structure provided on one end of the cutter body. The cutter body is provided with a main chip groove and an auxiliary chip groove which extend along the axial direction of the cutter body in a spiral manner and penetrate through the side face of the cutter body, the main chip groove is separated from the auxiliary chip groove along the circumferential direction of the cutter body, the main chip groove and the auxiliary chip groove are asymmetrically arranged by taking the axial lead of the cutter body as the center, and the main chip groove and the auxiliary chip groove also extend to the cutter tip structure; the tool nose structure comprises a first main rear tool face, a second main rear tool face, a first auxiliary rear tool face and a second auxiliary rear tool face which are sequentially arranged along the circumferential direction of the tool body, wherein the first main rear tool face is intersected with the second auxiliary rear tool face to define a main chisel edge, the second main rear tool face is intersected with the first auxiliary rear tool face to define an auxiliary chisel edge, the second auxiliary rear tool face is intersected with the side surface of the tool body to define a rear side edge, the side surface of the tool body is intersected with both the first main rear tool face and the second main rear tool face to define a towel back, the groove side wall surface of the main chip removal groove is intersected with the first main rear tool face to define a main cutting edge, and the groove side wall surface of the auxiliary chip removal groove is intersected with the first auxiliary rear tool face to define an auxiliary cutting edge; the maximum dimension of the auxiliary chip groove in the radial direction of the cutter body is 1.05 to 2.3 times that of the main chip groove in the radial direction of the cutter body, and the length of the auxiliary chisel edge is 0.15 to 0.7 times that of the main chisel edge.

Preferably, the length of the secondary chisel edge is 0.15 to 0.4 times the length of the primary chisel edge.

Preferably, the main chisel edge and the auxiliary chisel edge are each straight edges, the main cutting edge is a straight edge, and the auxiliary cutting edge is a curved edge.

Preferably, the towel back is composed of a structure formed by multiple sections of curves, and the rear side edge is a curve edge.

Preferably, the projection profiles of the towel back and the rear side blade along the first direction of the axial direction of the cutter body are positioned on the same circle, and the central angles occupied by the projection profiles of the towel back and the rear side blade on the circle are respectively alpha and beta, wherein alpha is 60 degrees to 70 degrees, and beta is 2 degrees to 16 degrees.

Preferably, α is 63 to 67 degrees and β is 4 to 12 degrees.

Preferably, the secondary flutes extend helically at least one revolution and the secondary flutes extend helically less than the primary flutes.

Preferably, the number of turns of the spiral extension of the auxiliary junk slot is more than 2 turns and less than 3 turns.

Preferably, the main chisel edge and the auxiliary chisel edge intersect and the intersection point is located on the axis of the cutter body.

Preferably, the projection profiles of the main chisel edge and the auxiliary chisel edge along the first direction of the cutter body axial direction are each straight line segments and are positioned on the same straight line.

Compared with the prior art, under the condition that the auxiliary chip groove and the main chip groove are offset, the maximum size of the auxiliary chip groove in the radial direction of the cutter body is 1.05 to 2.3 times that of the main chip groove in the radial direction of the cutter body, so that the depth of the auxiliary chip groove is increased, the length of an auxiliary chisel edge can be reduced, the cutting force can be reduced on the basis of ensuring the positioning performance of the drilling tool, the machining quality of a hole wall is improved, and the cutter breaking rate is reduced, and the reason is that: the chisel edge is cut by a negative rake angle, and the acting force of the processed material on the chisel edge is larger, so that the vibration of the drill point can be aggravated, and the processing quality of the hole wall is poor and the needle is broken. In addition, the single-edge tool can participate in cutting under the condition that the main cutting edge is worn or the feed amount is large, so that unnecessary heat and cutting force are caused, the auxiliary chisel edge can be kept away by reducing the length of the auxiliary chisel edge, the cutting heat and the cutting force are reduced, and the heat dissipation performance of the drilling tool can be improved. Meanwhile, the length of the auxiliary chisel edge is 0.15 to 0.7 times of that of the main chisel edge, so that the widths of the rear side edge and the towel back can be reduced, the contact area with the hole wall is reduced, the friction heat is reduced, and the quality of the hole wall is improved.

Drawings

Fig. 1 is a perspective view of a drilling tool of the present utility model.

Fig. 2 is a perspective view of the boring tool shown in fig. 1 at another angle.

Fig. 3 is a side view of the boring tool shown in fig. 1.

Fig. 4 is a perspective view of the boring tool shown in fig. 3 in the direction of arrow a.

FIG. 5 is a drawing of the drilling tool of FIG. 4 showing alpha, beta, L ₁ And L ₂ And (5) a subsequent projection view.

Fig. 6 is an internal view taken along line D-D in fig. 3.

Reference numerals illustrate:

cutter body 10, side face 11, main chip groove 12, groove side wall surface 121, auxiliary chip groove 13, groove side wall surface 131, cutter head structure 20, first main relief surface 21, second main relief surface 22, first auxiliary relief surface 23, second auxiliary relief surface 24, main chisel edge 25, length L of main chisel edge ₁ A minor chisel edge 26, a minor chisel edge length L ₂ A rear side edge 27, a back 28, a main cutting edge 291, a minor cutting edge 292, an intersection point P, and an axis C.

Detailed Description

In order to describe the technical content and constructional features of the present utility model in detail, the following description will be made with reference to the embodiments in conjunction with the accompanying drawings.

Referring to fig. 1 to 5, the drilling tool 100 of the present utility model includes a tool body 10 and a tool tip structure 20 disposed at one end of the tool body 10, alternatively, as an example, the tool tip structure 20 and the tool body 10 together form an integral structure, so that the tool body 10 and the tool tip structure 20 are made of the same material, so that the connection between the tool tip structure 20 and the tool body 10 is more stable and reliable, although the connection between the tool body 10 and the tool tip structure 20 may be other according to actual needs, so the utility model is not limited to fig. 1 to 3.

Meanwhile, the cutter body 10 is provided with a main chip groove 12 and an auxiliary chip groove 13 which extend spirally along the axial direction (direction indicated by arrow A and opposite direction) of the cutter body 10 and penetrate through the side face 11 of the cutter body 10, the main chip groove 12 and the auxiliary chip groove 13 also extend to the cutter tip structure 20, the main chip groove 12 is separated from the auxiliary chip groove 13 along the circumferential direction (direction indicated by arrow B) of the cutter body 10, the main chip groove 12 is arranged asymmetrically with the auxiliary chip groove 13 by taking the axial lead C of the cutter body 10 as the center, so that the main chip groove 12 and the auxiliary chip groove 13 are arranged in a biasing way, thereby being arranged in a large-small way on the cutter body 10, and the state is seenFig. 4 to 6; and in fig. 6, the maximum dimension R of the auxiliary chip groove 13 in the radial direction of the cutter body 10 ₂ Maximum radial dimension R of the main flutes 12 in the cutter body 10 ₁ 1.05 to 2.3 times; alternatively, in FIG. 2, as an example, the pitch D of the main flute 12 ₁ Pitch D of the secondary junk slot 13 ₂ The auxiliary chip grooves 13 and the main chip grooves 12 on the cutter body 10 are arranged densely and sparsely to ensure that the cutter body 10 has enough rigidity; of course, according to actual requirements, the pitch D of the main junk slots 12 ₁ Pitch D of the auxiliary junk slot 13 ₂ The relation of (2) may be other, so it is not limited thereto; in addition, R ₂ May also be R ₁ But not limited to, 1.05 times, 1.1 times, 1.2 times, 1.3 times, 1.4 times, 1.5 times, 1.6 times, 1.7 times, 1.8 times, 1.9 times, 2.0 times, 2.1 times, 2.2 times, or 2.3 times.

The cutting edge structure 20 includes a first main relief surface 21, a second main relief surface 22, a first sub relief surface 23, and a second sub relief surface 24, which are sequentially arranged in the circumferential direction of the cutter body 10; the first major relief surface 21 intersects the second minor relief surface 24 to define a major chisel edge 25 and the second major relief surface 22 intersects the first minor relief surface 23 to define a minor chisel edge 26. Alternatively, in FIG. 5, as an example, the length L of the minor chisel edge 26 ₂ Length L of main chisel edge 25 ₁ Is 0.15 to 0.7 times, in particular, the length L of the secondary chisel edge 26 ₂ Length L of main chisel edge 25 ₁ For example, 0.15 times, 0.2 times, 0.3 times, or 0.4 times, to effectively reduce the width of the rear side edge 27 and the towel back 28 described below, of course, the length L of the secondary chisel edge 26 as actually required ₂ Length L with main chisel edge 25 ₁ The multiple relation of (2) may be other, so it is not limited thereto; the second minor relief surface 24 intersects the side surface 11 of the cutter body 10 to define a relief edge 27, the side surface 11 of the cutter body 10 intersects both the first major relief surface 21 and the second major relief surface 22 to define a towel back 28, the flute side wall surface 121 of the major flute 12 intersects the first major relief surface 21 to define a major cutting edge 291, and the flute side wall surface 131 of the minor flute 13 intersects the first minor relief surface 23 to define a minor cutting edge 292, as shown in fig. 1, 4 and 5. More havePhysically, the following is:

as shown in fig. 2, the secondary junk slots 13 extend helically for at least one turn, the length of the secondary junk slots 13 extending helically is smaller than the length of the primary junk slots 12 extending helically, alternatively, the number of turns of the secondary junk slots 13 extending helically is greater than 2 turns and less than 3 turns, so that the influence on the rigidity of the cutter body 10 caused by excessive design of the number of turns of the secondary junk slots 13 is effectively avoided.

As shown in fig. 1, 4 and 5, the main chisel edge 25 and the auxiliary chisel edge 26 are each straight edges, alternatively, in fig. 3, as an example, the main chisel edge 25 and the auxiliary chisel edge 26 intersect and the intersection point P is located on the axis line C of the tool body 10, so as to play a role in positioning before the drilling tool 100 of the present utility model rotationally processes a workpiece, and the projection profiles of the main chisel edge 25 and the auxiliary chisel edge 26 along the first direction of the axial direction of the tool body 10 are each straight line segments and are located on the same straight line, so as to ensure the uniformity of the distribution of rotational cutting stress during the rotational processing of the drilling tool 100 of the present utility model on the workpiece, as shown in fig. 4 and 5; of course, the positions and relationships of the primary chisel edge 25 and the secondary chisel edge 26 may be other according to actual needs, and are not limited to those shown in fig. 1, 4, and 5. The main cutting edge 291 is a straight edge, and the minor cutting edge 292 is a curved edge, so that the cutting reliability of the drilling tool 100 of the present utility model is ensured.

As shown in fig. 1, 4 and 5, the back 28 is formed by a multi-section curve, and the rear edge 27 is a curve edge, alternatively, in fig. 4 and 5, as one illustration, the projection profiles of the back 28 and the rear edge 27 along the first direction of the axial direction of the cutter body 10 are located on the same circle, and the central angles occupied by the projection profiles of the back 28 and the rear edge 27 on the circle are respectively alpha and beta, wherein alpha is 60-70 degrees, and beta is 2-16 degrees, so that the design effectively reduces the widths of the back 28 and the rear edge 27, reduces the contact area with the hole wall more effectively, reduces the heat more effectively, and improves the processing quality of the hole wall more effectively. Specifically, α is 63 to 67 degrees, such as 63 degrees, 64 degrees, 65 degrees, 66 degrees or 67 degrees, β is 4 to 12 degrees, such as 4 degrees, 5 degrees, 6 degrees, 7 degrees, 8 degrees, 9 degrees, 10 degrees, 11 degrees or 12 degrees, so that the widths of both the back 28 and the rear edge 27 are minimized, the contact area with the hole wall is minimized, the heat is minimized, and the processing quality of the hole wall is maximized.

Compared with the prior art, when the auxiliary junk slot 13 and the main junk slot 12 are offset, namely, when the auxiliary junk slot 13 is asymmetrically arranged with the axial line C of the cutter body 10 as the center, the maximum dimension R of the auxiliary junk slot 13 in the radial direction of the cutter body 10 ₂ Maximum radial dimension R of the main flutes 12 in the cutter body 10 ₁ Is 1.05 to 2.3 times that of the secondary junk slots 13, and the length L of the secondary chisel edge 26 can be reduced ₂ On the basis of ensuring the positioning performance of the drilling tool 100, the cutting force can be reduced, the machining quality of the hole wall can be improved, and the cutter breaking rate can be reduced, because: the chisel edge 25 (26) is cut at a negative rake angle, and the workpiece has a large acting force on the chisel edge 25 (26), so that the vibration of the drill is increased, and the processing quality of the hole wall is poor and the hole is broken. In addition, the single-edge tool has the secondary cutting edge 292 involved in cutting in the case of abrasion of the primary cutting edge 291 or a large feed amount, resulting in unnecessary heat and cutting force, reducing the length L of the secondary chisel edge 26 ₂ The auxiliary chisel edge 26 can be kept away, the cutting heat and cutting force can be reduced, and the heat radiation performance of the drilling tool 100 of the present utility model can be improved. At the same time, due to the length L of the secondary chisel edge 26 ₂ Length L of main chisel edge 25 ₁ The width of the rear side blade 27 and the towel back 28 can be reduced at the same time by 0.15 to 0.7 times, the contact area with the hole wall is reduced, the friction heat is reduced, and the hole wall quality is improved.

Since the axial direction of the cutter body 10 is a double direction, in the drawing, the direction indicated by the arrow a is a first direction of the axial direction of the cutter body 10, and the opposite direction indicated by the arrow a is a second direction of the axial direction of the cutter body 10. In addition, the drilling tool 100 of the present utility model may be a single-blade drill.

The foregoing disclosure is only illustrative of the preferred embodiments of the present utility model and is not to be construed as limiting the scope of the utility model, which is defined by the appended claims.

Claims

1. The drilling tool comprises a tool body and a tool tip structure arranged at one end of the tool body, wherein the tool body is provided with a main chip removing groove and an auxiliary chip removing groove which extend along the axial direction of the tool body in a spiral manner and penetrate through the side surface of the tool body, the main chip removing groove is separated from the auxiliary chip removing groove along the circumferential direction of the tool body, the main chip removing groove and the auxiliary chip removing groove also extend to the tool tip structure, the main chip removing groove is asymmetrically arranged with the auxiliary chip removing groove by taking the axial lead of the tool body as the center, the tool tip structure comprises a first main rear tool face, a second main rear tool face, a first auxiliary rear tool face and a second auxiliary rear tool face which are sequentially arranged along the circumferential direction of the tool body, the first main rear tool face is intersected with the second auxiliary rear tool face to define a main chisel edge, the second main relief surface intersects the first auxiliary relief surface to define an auxiliary chisel edge, the second auxiliary relief surface intersects the side surface of the cutter body to define a rear side edge, the side surface of the cutter body intersects both the first main relief surface and the second main relief surface to define a towel back, the groove side wall surface of the main chip groove intersects the first main relief surface to define a main cutting edge, the groove side wall surface of the auxiliary chip groove intersects the first auxiliary relief surface to define an auxiliary cutting edge, characterized in that the maximum dimension of the auxiliary chip groove in the radial direction of the cutter body is 1.05 to 2.3 times the maximum dimension of the main chip groove in the radial direction of the cutter body, and the length of the auxiliary chisel edge is 0.15 to 0.7 times the length of the main chisel edge.

2. The drilling tool of claim 1, wherein the secondary chisel edge has a length of 0.15 to 0.4 times the length of the primary chisel edge.

3. The drilling tool of claim 1, wherein the primary and secondary chisel edges are each linear edges, the primary cutting edge is a linear edge, and the secondary cutting edge is a curvilinear edge.

4. The drilling tool of claim 1, wherein the towel back is a multi-curved structure and the rear edge is a curved edge.

5. The drilling tool of claim 1, wherein the projected profiles of the towel back and the rear side edge along the first direction of the axial direction of the cutter body are located on the same circle, and the projected profiles of the towel back and the rear side edge occupy the same circle at the central angles of α and β, respectively, wherein α is 60 to 70 degrees, and β is 2 to 16 degrees.

6. The drilling tool of claim 5, wherein α is 63 to 67 degrees and β is 4 to 12 degrees.

7. The drilling tool of claim 1, wherein the secondary flutes extend helically at least one revolution and the secondary flutes extend helically less than the primary flutes.

8. The drill tool of claim 7, wherein the number of turns of the secondary junk slot helical extension is greater than 2 turns and less than 3 turns.

9. The drilling tool of claim 1, wherein the primary chisel edge and secondary chisel edge both intersect and the intersection point is located on the axis of the cutter body.

10. The drilling tool of claim 1, wherein the projection profiles of both the primary chisel edge and the secondary chisel edge along the first direction of the cutter body axial direction are each straight line segments and lie on the same straight line.