High-performance three-edge hard alloy drill bit with water-drop-shaped chamfer
By setting a teardrop-shaped chamfer at the helical cutting edge shoulder of the three-flute carbide drill bit, combined with a specific helix angle and coating design, the problems of poor centering performance and short service life of traditional drill bits are solved, achieving higher machining accuracy and stability.
Patent Information
- Application Number
- CN202520669642.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-10
- Publication Date
- 2026-03-20
- Estimated Expiration
- 2035-04-10
AI Technical Summary
Traditional two-flute drill bits have poor centering performance, are prone to deviation, have a short service life, and limited machining feed speed, making it difficult to meet the needs of high-efficiency machining, especially in deep holes and complex working conditions where cutting effectiveness is poor.
A high-performance three-flute carbide drill bit is designed. The new design features a teardrop-shaped chamfer at the shoulder of the helical cutting edge, combined with a specific helix angle and clearance angle. The helical cutting edge, made of K40 carbide material and coated with fine-grained Al2O3 coating and nano-columnar MT-TiCN coating, is also designed.
It improves the service life and machining accuracy of drill bits, solves the problem of wear and chipping at the drill shoulder, increases tool life to 80mm, and makes machining more stable.
Smart Images
Figure CN224011294U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of drill bit, specifically, relate to a high performance three blade hard alloy drill bit with water droplet chamfer. BACKGROUND
[0002] In the field of mechanical processing, drilling operation is a common processing procedure. The traditional drilling processing usually adopts two-blade drill bit, however, the two-blade drill bit has obvious defects: first, the centering performance is poor, and it is easy to deviate during drilling, affecting the processing precision; second, the service life is short, and it needs to be frequently replaced, increasing the cost of downtime tool changing and labor cost; third, the processing feed speed is limited, and it is difficult to meet the efficient processing demand. In addition, when processing deep hole, the traditional drill bit is easy to wear and break at the shoulder, and the service life is short; facing complex working conditions such as cross hole and inclined surface entrance, the cutting effectiveness is poor, and the processing stability cannot be guaranteed.
[0003] In view of the above, a high-performance three-blade hard alloy drill bit with water droplet chamfer is provided to solve the above problems. SUMMARY
[0004] The utility model provides a high performance three blade hard alloy drill bit with water droplet chamfer, solve the problem that drill bit shoulder place is easy to wear and break.
[0005] The technical scheme of the utility model is as follows: including drill bit body, its characterized in being: the drill bit body is cylindrical straight handle structure, the front end of drill bit body is equipped with three equal width and central symmetry spiral chip removal groove, the adjacent spiral chip removal groove forms spiral cutting edge between, the shoulder of any spiral cutting edge is provided with water droplet chamfer, the chamfer angle of water droplet chamfer is 20 DEG, the width of water droplet chamfer is 1 / 10 of the diameter of drill bit body, the connecting part of water droplet chamfer and corresponding spiral cutting edge is all arc transition.
[0006] As a preferred technical scheme of the utility model, the end face of the drill bit body is provided with a cutting tip of 136°.
[0007] As a preferred technical scheme of the utility model, the core thickness of the spiral cutting edge is 20% of the diameter of the drill bit body.
[0008] As a preferred technical scheme of the utility model, the spiral angle of the spiral cutting edge is 30°, and the relief angle is 10°.
[0009] As a preferred technical scheme of the utility model, the drill bit body is made of K40 hard alloy material.
[0010] As a preferred technical scheme of the utility model, the spiral cutting edge is provided with a coating, and the coating adopts fine-crystal Al2O3 coating and nano columnar structure MT-TiCN.
[0011] The working principle and beneficial effects of the utility model are as follows:
[0012] The drill bit is provided with water-drop-shaped chamfers at the blade shoulders of the spiral cutting edges, and the angle and width of the water-drop-shaped chamfers are designed to prevent the drill bit from being abraded and broken, prolong the service life, and solve the problem of the easy abrasion and breakage of the tool blade shoulder by matching the special coating and suitable spiral angle and clearance angle, so that the tool life is improved to 80mm, the machining precision is higher, and the machining is more stable. BRIEF DESCRIPTION OF DRAWINGS
[0013] The utility model will be further described in detail in combination with the drawings and specific embodiments.
[0014] Fig. 1 It is a structural schematic view of the utility model;
[0015] Fig. 2 It is a structural schematic view of the spiral cutting edge of the utility model;
[0016] In the drawing: 1, drill bit body; 2, spiral chip removal groove; 3, spiral cutting edge; 4, water-drop-shaped chamfer; 5, cutting tip. DETAILED DESCRIPTION
[0017] The technical scheme in the embodiments of the utility model will be clearly and completely described in combination with the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by the person skilled in the art without creative labor are involved in the protection scope of the utility model. EMBODIMENT
[0018] As Figs. 1-2As shown, the embodiment proposes a high-performance three-blade carbide drill bit with water-drop-shaped chamfer, which comprises a drill bit body 1, the drill bit body 1 is made of K40 carbide material, the hardness can reach 89-95HRA, the bending strength is greater than or equal to 2100N / mm2, the drill bit body 1 is in a cylindrical straight shank structure, the front end of the drill bit body 1 is provided with three equal-width and center-symmetrical spiral flutes 2, the adjacent spiral flutes 2 form spiral cutting edges 3, the spiral cutting edges 3 are 30° in spiral angle and 10° in relief angle, the core thickness of the spiral cutting edges 3 is 20% of the diameter of the drill bit body 1, the width of the chisel edge of the spiral cutting edges 3 is 4% of the diameter of the drill bit body 1, the shoulder of any spiral cutting edge 3 is provided with a water-drop-shaped chamfer 4, the chamfer angle of the water-drop-shaped chamfer 4 is 20°, the width of the water-drop-shaped chamfer 4 is 1 / 10 of the diameter of the drill bit body 1, in the embodiment, the diameter of the drill bit body 1 is 11.5mm, so the width of the water-drop-shaped chamfer 4 is 1.15mm, the connecting parts of the water-drop-shaped chamfer 4 and the corresponding spiral cutting edges 3 are all circular arc transitions, the circular arc transitions are R0.3-R0.5, so as to avoid stress concentration.
[0019] The end surface of the drill bit body 1 is provided with a 136° cutting tip 5 in the center, so that the positioning is more accurate.
[0020] After multiple cutting tests, the water-drop-shaped chamfer 4 at the shoulder of the spiral cutting edge 3 is set to 30°, 20° and 10° in chamfer, the width of the water-drop-shaped chamfer 4 is set to 1 / 10, 1 / 15 and 1 / 20 of the diameter of the drill bit body 1, the chamfer connecting parts are all circular arc transitions, the chamfer angle and the width are combined for test, under the condition that the angle is 20° and the width is 1 / 10 of the diameter of the drill bit body 1 and other cutting parameters are uniform, the wear of the drill bit is optimal, the effectiveness is best, the drilling is more stable, and the service life is longer.
[0021] The spiral cutting edge 3 is provided with a coating, the coating adopts fine-grained Al2O3 coating and nano-pillar structure MT-TiCN, so as to effectively reduce the cutting resistance, inhibit the generation of built-up edge and ensure the stability in the machining process.
[0022] The drill bit is provided with the water-drop-shaped chamfer 4 at the shoulder of the spiral cutting edge 3, the angle and the width of the water-drop-shaped chamfer 4 are designed, so that the drill bit is not easy to wear and break, the service life is longer, the special coating, the suitable spiral angle and the relief angle solve the problem that the tool shoulder is easy to wear and break, the service life of the tool is improved to 80mm stably, the machining precision is higher and more stable.
[0023] The above is only a preferred embodiment of the utility model, and is not used to limit the utility model, any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model should be included in the protection scope of the utility model.
Claims
1. A high-performance three-flute carbide drill bit with a teardrop-shaped chamfer, comprising a drill bit body (1), characterized in that: The drill bit body (1) has a cylindrical straight shank structure. The front end of the drill bit body (1) is provided with three equally wide and centrally symmetrical spiral chip removal grooves (2). A spiral cutting edge (3) is formed between adjacent spiral chip removal grooves (2). A teardrop-shaped chamfer (4) is provided at the shoulder of any spiral cutting edge (3). The chamfer angle of the teardrop-shaped chamfer (4) is 20°. The width of the teardrop-shaped chamfer (4) is 1 / 10 of the diameter of the drill bit body (1). The connection between the teardrop-shaped chamfer (4) and the corresponding spiral cutting edge (3) is a rounded transition.
2. The high-performance three-flute carbide drill bit with a teardrop-shaped chamfer according to claim 1, characterized in that, The drill bit body (1) has a 136° cutting tip (5) at the center of its end face.
3. The high-performance three-flute carbide drill bit with a teardrop-shaped chamfer according to claim 1, characterized in that, The core thickness of the spiral cutting edge (3) is 20% of the diameter of the drill bit body (1).
4. A high-performance three-flute carbide drill bit with a teardrop-shaped chamfer according to claim 1, characterized in that, The spiral cutting edge (3) has a helix angle of 30° and a back angle of 10°.
5. A high-performance three-flute carbide drill bit with a teardrop-shaped chamfer according to claim 1, characterized in that, The drill bit body (1) is made of K40 cemented carbide.