Flat-angle margin microbit capable of stably guiding chips

Abstract

The utility model relates to the technical field of cutting tools, in particular to a flat-angle margin microbit capable of stably guiding chips, which comprises a drill edge and a drill handle, a connecting part is arranged between the drill edge and the drill handle, the drill edge comprises an inner core and a margin, and the margin is spirally distributed on the outer wall of the inner core. The edge position of the cross section of the edge strip extends outwards to form a right-trapezoid-shaped flat-angle protrusion, the inner core comprises a drill tip and a drill tail, the edge strip extends from the drill tip to the drill tail to form a first chip guide groove and a second chip guide groove, and the first chip guide groove and the second chip guide groove converge to form a third chip guide groove. The side face area of the drill edge is increased through the flat-angle protrusions, the first chip guiding grooves and the second chip guiding grooves are combined to form the third chip guiding grooves to reduce the length of the edge belt spacing part between the chip guiding grooves, and therefore the rigidity of the drill bit is improved, and when the edge belts rotate, trapezoidal slopes on the flat-angle protrusions make contact with a workpiece to be machined for guiding cutting. The cutting capacity of the drill is improved.

Description

Technical Field

[0001] This utility model mainly relates to the field of cutting tool technology, specifically a flat-angled micro drill bit with stable chip guiding. Background Technology

[0002] PCB board, also known as printed circuit board, requires the use of micro drills for micro-hole processing during its production. The two processes of PCB manufacturing and micro-drilling are highly interconnected. In the PCB manufacturing industry, in order to reduce costs and increase efficiency, the use of "multi-layered, high-thickness" PCB boards has become the industry mainstream, which places higher demands on micro-drilling manufacturing.

[0003] Existing technology includes a cutting edge located at the outermost radial edge of the drill body. The cutting edge is a V-shaped sharp corner. The cutting edge forms two chip guide grooves on the inner core. The sharp corner design of the drill bit has strong cutting ability during use, and the chip guide grooves provide uniform chip guidance, resulting in strong overall chip guidance ability. However, when the V-shaped sharp corner cuts the PCB, its side area is small, and the area of ​​the cutting edge interval between the two chip guide grooves is also small, resulting in low rigidity of the cutting edge part of the drill bit, which is prone to breakage during use. Utility Model Content

[0004] To address the aforementioned problems in the existing technology, the purpose of this utility model is to provide a flat-angled micro drill bit with stable chip guidance. By increasing the side area of ​​the drill bit through the flat-angled protrusion, and by merging the first and second chip guide grooves to form a third chip guide groove, the length of the blade spacing between the chip guide grooves is reduced, thereby improving the rigidity of the drill bit. When the blade rotates, the trapezoidal inclined surface on its flat-angled protrusion contacts the workpiece to guide the cutting, thereby improving the cutting capability of the drill bit.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a flat-angle cutting edge micro drill bit with stable chip guiding, comprising a drill bit and a drill shank, wherein a connecting part is provided between the drill bit and the drill shank, the drill bit comprises an inner core and a cutting edge, the cutting edge is spirally distributed on the outer wall of the inner core, the edge of the cross-section of the cutting edge extends outward to form a flat-angle protrusion, the inner core comprises a drill tip and a drill tail, the cutting edge extends from the drill tip to the drill tail to form a first chip guiding groove and a second chip guiding groove, the first chip guiding groove and the second chip guiding groove merge to form a third chip guiding groove.

[0006] Preferably, the cross-section of the cutting edge forms two arc-shaped blades, which are joined together along the inner core diameter direction. There are two flat-angle protrusions, with any one of them located on the edge of the arc-shaped blade. After rotating 180 degrees around the inner core, the flat-angle protrusion completely overlaps with the other flat-angle protrusion, and uniform cutting is performed through the two identical arc-shaped blades.

[0007] Furthermore, the edge of the arc-shaped cutting edge includes an arc edge and a straight edge. The flat-angle protrusion is a right-angled trapezoid. The right-angled edge of the flat-angle protrusion near the inside of the cutting edge connects to the straight edge of the arc-shaped cutting edge. The acute-angled edge of the flat-angle protrusion connects to the arc edge of the arc-shaped cutting edge. The length of the flat-angle protrusion along the straight edge of the arc-shaped cutting edge is L3, and the length of the flat-angle protrusion along the arc edge of the arc-shaped cutting edge is L4. The range of L3 is 0.016mm to 0.024mm, and the range of L4 is 0.006mm to 0.014mm. The right-angled trapezoidal flat-angle protrusion increases the area of ​​the edge position of the cutting edge, and the hypotenuse of the right-angled trapezoid guides the cutting and improves the cutting ability of the drill bit.

[0008] Preferably, the inner core is positioned on the cross-section of the cutting edge without extending beyond the edge of the cutting edge, and the connection between the cutting edge and the inner core allows the cutting edge to rotate synchronously for cutting when the inner core is rotated.

[0009] Furthermore, the diameter of the inner core ranges from 0.039 mm to 0.047 mm, and the length of the cutting edge at the corresponding position on the inner core is Φ, which ranges from 0.041 mm to 0.049 mm.

[0010] Preferably, the first and second chip guide grooves extend L1 from the drill tip towards the drill tee, and the end of the L1 length further extends L2 towards the drill tee. The end of the L2 length is the confluence of the first and second chip guide grooves. The third chip guide groove is located at the confluence. By confluencing the first and second chip guide grooves at the confluence, the length of the cutting edge interval between the two chip guide grooves is shortened.

[0011] Furthermore, the helical angle of the chip guide groove remains constant within the same length range. Within the length L1, the helical angle of the first chip guide groove is 43 degrees, the helical angle of the second chip guide groove is 43 degrees, within the length L2, the helical angle of the first chip guide groove is 50 degrees, the helical angle of the second chip guide groove is 60 degrees, and the helical angle of the third chip guide groove at the confluence point is 53 degrees. The chip guiding capability of the chip guide groove under different length ranges is adjusted by setting the groove helical angle.

[0012] Furthermore, the length of L1 is 0.6 mm, and the length of L2 is 0.5 mm.

[0013] Preferably, the connecting part includes a cylindrical structure and a frustum structure. The cylindrical structure is connected and fixed to the drill shank. One side of the frustum structure is integrally connected to the cylindrical structure, and the other side is tapered towards the drill bit to match the size of the drill bit. The drill shank and the drill bit are connected through the connecting part. The two sides of the connecting part have the same area as the structure to be connected, so the connection is stable.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] The drill bit's rigidity is improved by increasing the side surface area of ​​the drill bit through the flat-angle protrusions formed on both sides of the cutting edge cross section, and by merging the first and second chip guide grooves to form a third chip guide groove. This reduces the length of the cutting edge interval between the chip guide grooves. The cutting edge's cutting ability is improved by guiding the cutting through the trapezoidal inclined surface on the flat-angle protrusions to contact the workpiece when the cutting edge rotates.

[0016] The present invention will be explained in detail below with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0017] The accompanying drawings are only used to illustrate the principles, implementation methods, applications, features, and effects of the present invention and other related contents, and should not be considered as limitations on the present invention.

[0018] In the accompanying drawings of the instruction manual:

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0020] Figure 2 This is an enlarged view of the drill bit structure of this utility model;

[0021] Figure 3 This is a cross-sectional structural diagram of the drill bit of this utility model;

[0022] Figure label:

[0023] 1. Drill bit; 11. Inner core; 111. Drill tip; 112. Drill tee; 12. Cutting edge; 121. Flat angle protrusion; 122. First chip guide groove; 123. Second chip guide groove; 124. Third chip guide groove; 125. Arc-shaped cutting edge; 2. Connecting part; 21. Cylindrical structure; 22. Frustum structure; 3. Drill shank. Detailed Implementation Example 1

[0024] like Figures 1 to 3 As shown, a micro drill bit with a flat-angle cutting edge for stable chip guiding includes a drill bit 1 and a drill shank 3. A connecting part 2 is provided between the drill bit 1 and the drill shank 3. The drill bit 1 includes an inner core 11 and a cutting edge 12. The cutting edge 12 is spirally distributed on the outer wall of the inner core 11. The edge of the cross-section of the cutting edge 12 extends outward to form a flat-angle protrusion 121. The inner core 11 includes a drill tip 111 and a drill shank 112. The cutting edge 12 extends from the drill tip 111 towards the drill shank 112 to form a first chip guiding groove 122 and a second chip guiding groove 123. The first chip guiding groove 122 and the second chip guiding groove 123 merge to form a third chip guiding groove 124.

[0025] The first chip guide groove 122 and the second chip guide groove 123 extend L1 from the drill tip 111 towards the drill shank 112, with a length of L1 of 0.6 mm. The end of L1 extends further towards the drill shank by a length L2 of 0.5 mm. The end of L2 is the confluence of the first chip guide groove 122 and the second chip guide groove 123. The third chip guide groove 124 is located at the confluence. When the drill bit 1 rotates clockwise, the second chip guide groove 123 first contacts the chips to guide them, and the first chip guide groove 122 subsequently contacts the chips to assist in chip guidance. The same length range... The helical angle of the chip guide grooves within the enclosure remains constant. Generally, the size of the helical angle is positively correlated with the chip guiding capacity and negatively correlated with the drill bit rigidity. The initial cutting within the L1 length produces less debris. The helical angle of the first chip guide groove 122 is 43 degrees, and the helical angle of the second chip guide groove 123 is 43 degrees. The accumulation of debris within the L2 length increases. The helical angle of the first chip guide groove 122 is set to 50 degrees, and the helical angle of the second chip guide groove 123 is set to 60 degrees to improve the chip guiding capacity. The cutting is finished at the confluence point. The helical angle of the third chip guide groove 124 is set to 53 degrees to balance the chip guiding capacity.

[0026] The cross-section of the cutting edge 12 forms two arc-shaped blades 125, which are joined together along the diameter of the inner core 11. The flat-angle protrusions 121 are right-angled trapezoids, and there are two of them. One of the flat-angle protrusions 121 is located on the edge of the arc-shaped blade 125. After rotating 180 degrees about the inner core 11, the flat-angle protrusion 121 completely overlaps with the other flat-angle protrusion 121. The edge of the arc-shaped blade 125 includes both curved and straight edges. The flat-angle protrusions 121 are close to the cutting edge 125. 2. The right-angled side inside is connected to the straight side of the arc-shaped blade, and the acute-angled side of the flat-angled protrusion 121 is connected to the arc-shaped blade. The length of the flat-angled protrusion 121 along the straight side of the arc-shaped blade is L3, and the length of the flat-angled protrusion 121 along the arc-shaped blade is L4. The range of L3 is 0.016mm to 0.024mm, and the range of L4 is 0.006mm to 0.014mm. After the blade rotates clockwise, the trapezoidal inclined surface on the flat-angled protrusion 121 contacts the product to be cut and guides the cutting.

[0027] The connecting part 2 includes a cylindrical structure 21 and a frustum structure 22. The cylindrical structure 21 fits into the drill shank 3 and is fixedly connected to the drill shank 3. One side of the frustum structure 22 is integrally connected to the cylindrical structure 21, and the other side shrinks towards the drill bit 1 to fit the size of the drill bit 1.

[0028] The inner core 11 is positioned on the cross-section of the blade 12 without extending beyond the edge of the blade 12. The diameter of the inner core 11 is between 0.039 mm and 0.047 mm. The length of the blade 12 at the corresponding position on the inner core is Φ, which is between 0.041 mm and 0.049 mm.

[0029] The implementation principle of Embodiment 1 of this application is as follows: When the drill bit is in working condition, it rotates clockwise. The outermost flat-angle protrusion 121 of the cutting edge 12 first contacts the product to be cut, and the cutting is guided along the trapezoidal inclined surface on the flat-angle protrusion 121. This improves the cutting ability of the drill bit while having little impact on rigidity. After the cutting starts, the chips generated are first guided into the first chip guide groove 122 along L1. After the first chip guide groove 122 is filled, it is guided into the second chip guide groove 123. When the cutting reaches L2, the helical angles of the first chip guide groove 122 and the second chip guide groove 123 both increase to meet the chip guide requirements after a large amount of chips have accumulated. When the cutting reaches the confluence point, the cutting edge interval between the first chip guide groove 122 and the second chip guide groove 123 disappears, causing the two chip guide grooves to merge into the third chip guide groove 124. The drill bit is rigid and not easy to break during use.

[0030] It will be apparent to those skilled in the art that this application is not limited to the details of the exemplary embodiments described above, and that this application can be implemented in other specific forms without departing from its essential characteristics. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this application is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this application. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A micro drill with a flat-angle blade for stable chip guidance, comprising a drill blade (1) and a drill shank (3), characterized in that: A connecting portion (2) is provided between the drill blade (1) and the drill shank (3); the drill blade (1) comprises an inner core (11) and a cutting edge (12); the cutting edge (12) is spirally distributed on the outer wall of the inner core (11); the edge of the cross section of the cutting edge (12) extends outward to form a flat-angle protrusion (121); the inner core (11) comprises a drill tip (111) and a drill tail (112); the cutting edge (12) extends from the drill tip (111) toward the drill tail (112) to form a first chip guide groove (122) and a second chip guide groove (123); the first chip guide groove (122) and the second chip guide groove (123) merge to form a third chip guide groove (124).

2. A micro drill with a flat-angle land with stable chip guide according to claim 1, characterized in that: The cross section of the blade band (12) forms two arc-shaped blades (125), the two arc-shaped blades (125) are spliced ​​with each other along the diameter direction of the inner core (11), the number of the flat-angle protrusions (121) is two, any one of the flat-angle protrusions (121) is located on the edge of the arc-shaped blade (125), and the flat-angle protrusion (121) completely overlaps with the other flat-angle protrusion (121) after rotating 180 degrees with the inner core (11) as the rotation axis.

3. A micro drill with a flat-angle land for stable chip guidance according to claim 2, characterized in that: The edge of the arc-shaped blade (125) comprises an arc edge and a straight edge, the flat angle protrusion (121) is in the shape of a right-angled trapezoid, the right-angle edge of the flat angle protrusion (121) close to the inside of the blade band (12) is connected to the straight edge of the arc-shaped blade, the acute angle edge of the flat angle protrusion (121) is connected to the arc edge of the arc-shaped blade, the length of the flat angle protrusion (121) along the straight edge of the arc-shaped blade is L3, the length of the flat angle protrusion (121) along the arc edge of the arc-shaped blade is L4, the range of L3 is 0.016 mm to 0.024 mm, and the range of L4 is 0.006 mm to 0.014 mm.

4. The flat-angled edge micro drill with stable chip guide according to claim 1, characterized in that: The corresponding position of the inner core (11) on the cross section of the edge band (12) does not exceed the edge of the edge band (12).

5. A micro drill with a flat-angle land for stable chip guidance according to claim 4, characterized in that: The diameter of the inner core (11) ranges from 0.039 mm to 0.047 mm, the length of the blade band (12) at a corresponding position of the inner core is Φ, and the range of Φ is between 0.041 mm and 0.049 mm.

6. A micro drill with a flat-angle land for stable chip guidance according to claim 1, characterized in that: The first chip guide groove (122) and the second chip guide groove (123) extend from the drill tip (111) to the drill tail (112) along a length L1, and the end of the length L1 further extends to the drill tail in the direction of the length L2, and the end of the length L2 is the confluence of the first chip guide groove (122) and the second chip guide groove (123), and the third chip guide groove (124) is located at the confluence.

7. A micro drill with a flat-angle land for stable chip guidance according to claim 6, characterized in that: The spiral angle of the chip guide groove remains unchanged within the same length range. The spiral angle of the first chip guide groove (122) within the length L1 is 43 degrees, and the spiral angle of the second chip guide groove (123) is 43 degrees. The spiral angle of the first chip guide groove (122) within the length L2 is 50 degrees, and the spiral angle of the second chip guide groove (123) is 60 degrees. The spiral angle of the third chip guide groove (124) at the confluence is 53 degrees.

8. The flat-angled edge micro drill with stable chip guide according to claim 6, characterized in that: The length of L1 is 0.6 mm, and the length of L2 is 0.5 mm.

9. The flat-angled edge micro drill with stable chip guide according to claim 1, characterized in that: The connecting portion (2) comprises a cylindrical structure (21) and a truncated cone structure (22); the cylindrical structure (21) is connected and fixed to the drill shank (3); one side of the truncated cone structure (22) is integrally connected to the cylindrical structure (21), and the other side of the truncated cone structure (22) is contracted towards the drill blade (1) to match the size of the drill blade (1).

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