High-rigidity four-edge integral hard alloy drill bit
By designing a high-rigidity four-flute solid carbide drill bit, the problems of runout deformation, cutting vibration and built-up edge of traditional drill bits in deep hole machining and difficult-to-cut materials have been solved, improving machining accuracy and life, and enhancing machining efficiency and stability.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-08
- Publication Date
- 2026-04-07
AI Technical Summary
Traditional drill bits are prone to wobbling and deformation, resulting in large cutting vibrations, insufficient machining accuracy and lifespan when machining deep holes or cutting hard materials. Furthermore, the cutting edge is prone to chipping when machining difficult-to-cut materials, leading to low machining efficiency. Additionally, they are prone to built-up edge formation when machining cross holes or inclined planes, affecting stability.
A high-rigidity four-flute integral carbide drill bit is designed, using K40 carbide material, with a spiral cutting edge angle of 30°, a rake angle of 10°, and a core thickness ratio of 50%. The spiral cutting edge is coated with fine-grained Al2O3 and nano-columnar MT-TiCN coating, combined with a cross-shaped reinforcement structure.
It improves drilling accuracy and lifespan, increases processing efficiency, reduces cutting edge wear, enhances stability, saves on reamer and manual tool replacement costs, and achieves H7-level hole accuracy and Ra1.4 surface roughness.
Smart Images
Figure CN224088027U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to drill bit technical field, specifically, relate to a high rigidity four blade integral hard alloy drill bit. BACKGROUND
[0002] The hard alloy drill bit for deep hole machining is a key tool in the field of machining, and the structural design thereof directly affects machining efficiency and machining precision. Traditional drilling machining usually adopts a two-blade drill bit, and the core thickness of the two-blade drill bit is usually only 20%-30% of the diameter of the drill bit. When deep hole machining or hard material cutting is performed, the two-blade drill bit is prone to deflection and deformation, especially when machining quenched and tempered steel with HRC 40 or above, the cutting vibration is significantly increased, resulting in that the hole diameter deviation exceeds IT9 level, and the surface roughness Ra is greater than or equal to 2.0 microns. When machining difficult-to-cut materials such as titanium alloy and nickel-based alloy, the average machining life of the ordinary hard alloy tool is less than 50 mm due to insufficient bending strength and poor coating adhesion, and the "drill-reamer" composite process needs to be used to achieve H7 level hole precision, which increases the cost of reamer and tool changing time and reduces the machining efficiency. When the existing drill bit is used to machine cross holes or inclined surface entrances, the built-up edge is easily generated, the cutting force fluctuation is more than 20%, and the machining stability is seriously affected.
[0003] In view of the above, the high rigidity four-blade integral hard alloy drill bit is provided to solve the above problems. CONTENT OF THE UTILITY MODEL
[0004] The utility model provides a high rigidity four-blade integral hard alloy drill bit, and solves the problems of poor drilling precision, poor roughness, short tool life and low machining efficiency.
[0005] The technical scheme of the utility model is as follows: a base body is provided, and the base body is characterized in that: the base body is in a cylindrical straight shank structure, four equal-width and center-symmetrical spiral chip removal grooves are arranged at the front end of the base body, spiral cutting edges are formed between adjacent spiral chip removal grooves, the spiral angle of the spiral cutting edge is 30°, the rake angle is 10°, the core thickness of the spiral cutting edge is 45-55% of the total diameter of the base body, and the end face of the base body is in a cross-shaped reinforcing structure.
[0006] As a preferred technical scheme of the utility model, the end face of the base body is provided with a cutting tip with an angle of 118°-135°.
[0007] As a preferred technical scheme of the utility model, a rounded transition surface is arranged at the junction between the spiral cutting edge and the corresponding spiral chip removal groove, and the curvature radius of the rounded transition surface is 0.1-0.3 mm.
[0008] As a preferred technical scheme of the utility model, the base body is made of K40 hard alloy material.
[0009] 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.
[0010] The working principle and beneficial effects of the utility model are as follows:
[0011] The drill bit solves the problems of poor drill precision and roughness of the cutter by the four-blade design, reasonable core thickness proportion and cutting angle, higher machining precision, selection of the helix angle of 30°, the rake angle of 10°, the core thickness proportion of 50%, smaller blade wear, the cutter life can be improved to 80mm, the cost of a set of reamer and manual tool changing is saved, and the machining efficiency is higher and more stable. BRIEF DESCRIPTION OF DRAWINGS
[0012] The utility model will be further described in detail in combination with the drawings and specific embodiments.
[0013] Fig. 1 The figure is a structural schematic view of the utility model;
[0014] Fig. 2 The figure is a structural schematic view of the spiral cutting edge of the utility model;
[0015] In the figure, 1 is a base body, 2 is a spiral chip removal groove, 3 is a spiral cutting edge, 4 is a cutting tip, and 5 is a rounded transition surface. DETAILED DESCRIPTION
[0016] 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 a 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
[0017] As Figs. 1-2As shown, the embodiment proposes a high-rigidity four-blade integral hard alloy drill bit, which comprises a base body 1, the base body 1 is made of K40 hard alloy and has a hardness of 89-95HRA and a bending strength greater than or equal to 2100N / mm2, the base body 1 has a cylindrical straight shank structure, facilitating connection with a machine tool spindle or a tool shank, four equal-width and center-symmetrical spiral chip removal grooves 2 are arranged at the front end of the base body 1, and spiral cutting edges 3 are formed between adjacent spiral chip removal grooves 2, the four spiral cutting edges 3 can make cutting more stable, and are suitable for deep hole machining of hard materials, the core thickness of the spiral cutting edges 3 is 50% of the total diameter of the base body 1, so that the rigidity is better and the cutting speed and feed rate are higher, the hole surface precision after machining can reach Ra1.4, the hole bottom precision can reach H7, and the drill bit is used instead of a reamer, the end face of the base body 1 has a cross-shaped reinforcing structure, and the end face of the base body 1 is provided with a cutting tip 4 with an angle of 118°-135°, and the positioning is accurate.
[0018] A rounded transition surface 5 is arranged at the junction of the spiral cutting edge 3 and the corresponding spiral chip removal groove 2, and the curvature radius of the rounded transition surface 5 is 0.1-0.3mm. Through multiple cutting tests, the front angle is 10°, 15° and 20° respectively, the spiral angle is 30°, 35° and 40° respectively, and the core thickness ratio is 45%, 50% and 55% respectively. When the spiral angle is set to 30°, the front angle is 10°, and the core thickness ratio is 50%, the blade wear is the smallest under the condition that the number of machined holes is consistent.
[0019] A coating is arranged on the spiral cutting edge 3, and the coating adopts fine-grained Al2O3 coating and nano-pillar structure MT-TiCN. The cutting resistance can be effectively reduced, the generation of built-up edge can be inhibited, and the stability in the machining process can be ensured.
[0020] The drill bit solves the problems of poor drill hole precision and roughness of the tool, has higher machining precision, and can improve the tool life to 80mm stably, saves the cost of a reamer and manual tool changing, and has higher and more stable machining efficiency.
[0021] The above is only a preferred embodiment of the utility model, and does not limit the utility model, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.
Claims
1. A high-rigidity four-flute solid carbide drill bit, comprising a matrix (1), characterized in that: The base (1) has a cylindrical straight shank structure. The front end of the base (1) is provided with four equally wide and centrally symmetrical spiral chip removal grooves (2). A spiral cutting edge (3) is formed between adjacent spiral chip removal grooves (2). The spiral angle of the spiral cutting edge (3) is set to 30° and the rake angle is set to 10°. The core thickness of the spiral cutting edge (3) is 45-55% of the total diameter of the base (1). The end face of the base (1) has a cross-shaped reinforcing structure.
2. The high-rigidity four-flute solid carbide drill bit according to claim 1, characterized in that, The end face of the substrate (1) is provided with a cutting tip (4) of 118°-135°.
3. The high-rigidity four-flute solid carbide drill bit according to claim 1, characterized in that, The helical cutting edge (3) and the corresponding helical chip removal groove (2) are provided with a rounded transition surface (5), and the radius of curvature of the rounded transition surface (5) is 0.1-0.3mm.
4. A high-rigidity four-flute solid carbide drill bit according to claim 1, characterized in that, The substrate (1) is made of K40 hard alloy.