Left-hand and right-hand combined chip breaking double-edge flat-bottom milling cutter
By designing a left-right helical combined chip-breaking double-edged flat end mill, the problem of delamination in PCB circuit board processing by existing end mills is solved. Through the interlocking closed right-hand and left-hand helical thread segments and chip removal groove structure, efficient chip removal is achieved, improving the processing quality of PCB circuit boards.
Patent Information
- Application Number
- CN202422851381.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-21
- Publication Date
- 2025-11-14
- Estimated Expiration
- 2034-11-21
AI Technical Summary
Existing right-hand spiral top-discharge double-edged flat end mills cannot meet the chip removal requirements of special board materials, resulting in delamination of PCB circuit boards during processing, affecting their quality and service life.
A double-edged flat end mill with a left-right combined helical chip breaking mechanism is designed. The two ends of the cutting edge are respectively provided with right-hand and left-hand threaded sections. Chip removal grooves and peripheral cutting edges are provided on the threaded sections. The threaded sections are connected and closed to form left-hand and right-hand threads, which enhances the chip removal capacity and prevents the formation of long strips of chips. Chip removal efficiency is improved by chip separation grooves and clearance grooves.
This effectively avoids the delamination problem during PCB circuit board processing, improving processing quality and efficiency.
Smart Images
Figure CN223544163U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a milling cutter, and more particularly to a left-right rotating combined chip-breaking double-edged flat-bottom milling cutter. Background Technology
[0002] Existing milling cutters are generally right-hand spiral top-discharge double-edged flat-bottom milling cutters with a thread angle of 30° and a flat-bottomed cutting face. The cutting face is tip-raised (the main cutting face is straight). They can only be used for conventional top-discharge applications and cannot be used for special sheet metal chip removal applications.
[0003] Currently, the heat generated by traditional milling cutters during processing is absorbed by the PCB circuit board. After absorbing heat, the PCB circuit board, composed of resin-to-resin or resin-to-copper foil, experiences internal stress due to the different coefficients of thermal expansion between the different materials. When the adhesive strength between resins or between resin and copper foil is insufficient to resist this internal stress, delamination occurs, affecting the quality and lifespan of the PCB circuit board. To solve the delamination problem during PCB processing and ensure that the cutting tools meet the requirements for PCB routing, a better milling cutter is needed. Utility Model Content
[0004] The purpose of this utility model is to provide a left-right rotating combined chip-breaking double-edged flat end mill, which can solve the delamination problem during PCB circuit board processing and improve the processing quality of PCB circuit boards.
[0005] To achieve the above objectives, the present invention provides a left-right spiral combined chip-breaking double-edged flat end mill comprising a cutting edge and a shank. The front end face of the cutting edge is provided with a cutting tip. The end of the cutting edge near the cutting tip is provided with a right-hand spiral threaded section, and the end of the cutting edge away from the cutting tip is provided with a left-hand spiral threaded section. The right-hand spiral threaded section is provided with a right-hand spiral chip removal groove and a right-hand spiral circumferential cutting edge, and the left-hand spiral threaded section is provided with a left-hand spiral chip removal groove and a left-hand spiral circumferential cutting edge. The right-hand spiral threaded section and the left-hand spiral threaded section are connected and closed, and the length of the connection and closure is in the range of 0.05-1.0 mm. The left-hand spiral chip removal groove and the right-hand spiral chip removal groove extend to the connection and closure point respectively.
[0006] Compared with the prior art, this utility model provides right-hand threaded sections and left-hand threaded sections at both ends of the cutting edge. The right-hand threaded section has a right-hand chip removal groove and a right-hand peripheral cutting edge, while the left-hand threaded section has a left-hand chip removal groove and a left-hand peripheral cutting edge. The right-hand threaded section and the left-hand threaded section are connected and closed, so the cutting edge of the milling cutter has both left-hand and right-hand threads. The right-hand thread is closer to the tip of the cutter and the left-hand thread is closer to the shank. The left and right threads are connected and closed, so chip breaking can be performed at the junction to prevent the formation of long strips of dust. It also has the function of collecting and discharging the dust towards the middle of the cutting edge of the cutter body. This can prevent the delamination of PCB circuit boards during processing and improve the processing quality of PCB circuit boards.
[0007] Preferably, the flank face of the left-hand rotary cutting edge is provided with a chip-dispersing groove. The chip-dispersing groove allows for timely discharge of powder and debris, preventing powder and debris from remaining inside and causing blockages.
[0008] Specifically, the number of chip-separating grooves is at least two.
[0009] Specifically, the cutting diameter of the cutting edge is 6mm, the depth of the chip-breaking groove is 0.3-0.5mm, and the width of the chip-breaking groove is 0.07-1.03mm.
[0010] Preferably, the flank face of the left-hand circular cutting edge has a clearance groove along the left-hand direction. By providing the clearance groove, the outer side of the cutting edge can transition gradually, making the milling cutter more coordinated, and the chip removal space can be increased.
[0011] Specifically, an arc-shaped transition groove is provided between the end of the clearance groove near the cutting edge and the shank. This arc-shaped transition groove further increases the chip removal space of the end mill.
[0012] Preferably, the rake angle of the right-hand circular cutting edge ranges from 13 to 17 degrees, and the clearance angle ranges from 18 to 22 degrees. By limiting the rake angle and clearance angle of the rear circular cutting edge to a certain angle, the chip-cutting ability of the milling cutter can be improved, effectively enhancing the performance of the milling cutter.
[0013] Preferably, the angle between the left-hand and right-hand chip removal grooves is 27-33 degrees. By limiting the angle of the left-hand and right-hand chip removal grooves to a certain angle, the chip removal capacity of the chip removal grooves can be guaranteed.
[0014] Preferably, the blade tip has a crescent-shaped structure. The crescent-shaped structure makes the cutting edge sharper, which is beneficial for cutting.
[0015] Preferably, the primary cutting face angle of the blade is 18-22 degrees, and the secondary cutting face angle is 28-34 degrees. By limiting the primary and secondary cutting face angles to a certain angle, the blade can be made sharper, which is beneficial for cutting. Attached Figure Description
[0016] Figure 1 This is a side view of the structure of the left-right rotating combined chip-breaking double-edged flat end mill of this utility model.
[0017] Figure 2 This is a side view of the cutting edge of the left-right rotating combined chip-breaking double-edged flat end mill of this utility model.
[0018] Figure 3 This is a structural diagram of the front end face of the left-right rotating combined chip-breaking double-edged flat end mill of this utility model.
[0019] Figure 4 yes Figure 2 Enlarged view of section A.
[0020] Figure 5 yes Figure 2 Enlarged view of section B.
[0021] Figure 6 yes Figure 2 Enlarged view of section C. Detailed Implementation
[0022] To explain in detail the technical content, structural features, and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.
[0023] like Figure 1 and Figure 2 As shown, the left-right combined chip-breaking double-edged flat end mill 100 of this utility model includes a cutting edge 1 and a shank 2. The front end face of the cutting edge 1 is provided with a cutting tip 11. The end of the cutting edge 1 near the cutting tip 11 is provided with a right-hand threaded section 12, and the end of the cutting edge 1 away from the cutting tip 11 is provided with a left-hand threaded section 13. The right-hand threaded section 12 is provided with a right-hand chip removal groove 121 and a right-hand peripheral cutting edge 122. There are two right-hand chip removal grooves 121 and two right-hand peripheral cutting edges 122. The left-hand threaded section 13 is provided with a left-hand chip removal groove 131 and two left-hand peripheral cutting edges 132. The right-hand threaded section 12 and the left-hand threaded section 13 are connected and closed, and the length L of the connection and closure is in the range of 0.05-1.0mm. The left-hand chip removal groove 131 and the right-hand chip removal groove 121 extend to the connection and closure point.
[0024] Please see Figure 2 and Figure 5The left-hand circular cutting edge 132 has a chip-dispersing groove 134 on its flank face 133. The chip-dispersing groove 134 allows for timely discharge of chips, preventing them from accumulating and causing blockages. There are at least two chip-dispersing grooves 134. In this embodiment, there are six chip-dispersing grooves 134, with three equally spaced grooves on the flank face 133 of each left-hand circular cutting edge 132. Specifically, the cutting diameter φ of the cutting edge 1 is 6 mm, the depth h of the chip-dispersing groove 134 ranges from 0.3 to 0.5 mm, and the width n of the chip-dispersing groove 134 ranges from 0.07 to 1.03 mm. The flank face 133 of the left-hand circular cutting edge 132 has a clearance groove 135 along the left-hand direction; similarly, the flank face of the right-hand circular cutting edge 122 has a clearance groove (not shown in the figure) along the right-hand direction. In this embodiment, each left-hand circular cutting edge 132 has six clearance grooves 135 on its flank face 133. By providing clearance grooves 135, the outer side of the cutting edge 1 can transition smoothly, making the milling cutter more coordinated, and the chip removal space can be increased. An arc-shaped transition groove 136 is provided between the end of the clearance groove 135 near the cutting edge 1 and the shank 2. The arc-shaped transition groove 136 further improves the coordination of the milling cutter and increases its chip removal space.
[0025] Please see Figure 2 and Figure 3 The right-hand circular cutting edge 122 has a rake angle α ranging from 13 to 17 degrees and a clearance angle β ranging from 18 to 22 degrees. By limiting the rake angle α and clearance angle β to certain angles, the cutting ability of the milling cutter can be improved, effectively enhancing its performance. The cutting tip 11 is not raised and has a crescent-shaped structure. The crescent-shaped structure makes the cutting edge sharper, which is beneficial for cutting.
[0026] Please see Figure 2 and Figure 4 The angle γ of the left-handed chip removal groove 131 and the right-handed chip removal groove 121 ranges from 27 to 33 degrees. By limiting the angle of the left-handed chip removal groove 131 and the right-handed chip removal groove 121 to a certain angle, the chip removal capacity of the chip removal groove can be guaranteed.
[0027] Please see Figure 2 and Figure 6 The primary blade face angle δ of the blade 1 ranges from 18 to 22 degrees, and the secondary blade face angle θ ranges from 28 to 34 degrees. By limiting the primary blade face angle δ and the secondary blade face angle θ to a certain angle, the blade 1 can be made sharper, which is beneficial for cutting.
[0028] Compared with the prior art, this utility model provides a right-hand threaded section 12 and a left-hand threaded section 13 at both ends of the cutting edge 1. The right-hand threaded section 12 is provided with a right-hand chip removal groove 121 and a right-hand peripheral cutting edge 122, and the left-hand threaded section 13 is provided with a left-hand chip removal groove 131 and a left-hand peripheral cutting edge 132. The right-hand threaded section 12 and the left-hand threaded section 13 are connected and closed, so that the cutting edge 1 of the milling cutter has both left-hand and right-hand threads. The end near the tip 11 is right-handed and the end near the shank 2 is left-handed. The left and right threads are connected and closed, so chip breaking can be performed at the junction without forming long strips of dust. It also has the function of collecting and discharging the dust towards the middle of the cutting edge 1 of the cutter body. This can avoid delamination of PCB circuit boards during processing and improve the processing quality of PCB circuit boards.
[0029] The above-disclosed examples are merely preferred embodiments of the present utility model and should not be construed as limiting the scope of the present utility model. Therefore, any equivalent changes made in accordance with the scope of the present utility model application shall still fall within the scope of the present utility model.
Claims
1. A left- and right-hand rotary combined chip-breaking double-edged flat end mill, characterized in that: The device includes a cutting edge and a shank. The front end of the cutting edge is provided with a tip. The end of the cutting edge near the tip is provided with a right-hand threaded section, and the end of the cutting edge away from the tip is provided with a left-hand threaded section. The right-hand threaded section is provided with a right-hand chip removal groove and a right-hand circumferential cutting edge, and the left-hand threaded section is provided with a left-hand chip removal groove and a left-hand circumferential cutting edge. The right-hand threaded section and the left-hand threaded section are connected and closed, and the length of the connection and closure is in the range of 0.05-1.0 mm. The left-hand chip removal groove and the right-hand chip removal groove extend to the connection and closure point respectively.
2. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 1, characterized in that: The back face of the left-hand rotary cutting edge is provided with a chip-breaking groove.
3. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 2, characterized in that: The number of chip-breaking grooves is at least two.
4. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 2, characterized in that: The cutting diameter of the cutting edge is 6mm, the depth of the chip-breaking groove is 0.3-0.5mm, and the width of the chip-breaking groove is 0.07-1.03mm.
5. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 1, characterized in that: The back face of the left-hand circular cutting edge is provided with a clearance groove along the left-hand direction.
6. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 5, characterized in that: An arc transition groove is provided between the end of the clearance groove near the blade and the handle.
7. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 1, characterized in that: The angle range of the front angle of the right-hand rotating blade is 13-17 degrees, and the angle range of the rear angle is 18-22 degrees.
8. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 1, characterized in that: The angles of the left-handed and right-handed chip removal grooves are 27-33 degrees.
9. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 1, characterized in that: The blade tip has a crescent-shaped structure.
10. The left- and right-hand rotary combined chip-breaking double-edged flat end mill as described in claim 1, characterized in that: The primary cutting face angle of the blade is 18-22 degrees, and the secondary cutting face angle is 28-34 degrees.