Composite-edge efficient ball-end super-dense-tooth milling cutter

Abstract

The utility model discloses a high-efficiency ball-end ultra-dense tooth milling cutter with a composite blade, which belongs to the technical field of milling cutters and comprises a milling cutter body, the milling cutter body comprises a cutter body and a blade component, the blades are distributed on the outer surface of the cutter body along the circumferential direction, and the blades are unequally distributed on the cutter body; each blade comprises a margin, the width value of the margin is 1% of the blade diameter, and the margin is distributed at the + / -75-degree position of the ball head; the edge strip is smooth in surface, has certain hardness and wear resistance, can effectively restrain the retreating of the edge point caused by the wear of the cutter, and ensures the contour precision of the ball head, so that the cutting precision is ensured. The tool nose is arranged at the foremost end of the blade, the tool nose is provided with the two contact points, and the two contact points of the tool nose are both located at the foremost end of the blade, so that the abrasion problem caused by stress concentration possibly occurring to a single contact point and zero linear speed is effectively avoided.

Description

Technical Field

[0001] This utility model relates to the field of milling cutters, and more specifically, to a composite-edge high-efficiency ball-end milling cutter with ultra-dense teeth. Background Technology

[0002] In modern manufacturing, especially in the automotive mold manufacturing sector, there are extremely high requirements for the machining precision, surface quality, and production efficiency of parts. Automotive molds are mainly made of materials such as cast iron (e.g., ductile iron) and hardened tool steel (e.g., Cr12MoV). While ductile iron generally has low strength and hardness (HRC 25-30°), making it easy to cut, it contains a large number of alloying elements (e.g., Cr, Mn, Mo). These elements, while improving the material's hardening and wear resistance, also lead to rapid tool wear during cutting, significantly reducing tool life. Currently, reducing the cutting speed is often used to extend tool life, but this results in low machining efficiency. For example, when the cutting speed exceeds 100 m / min, tool life is drastically reduced to approximately 0.5 hours, severely impacting production efficiency.

[0003] When hardened tool steel is used in automotive mold parts, its hardness after quenching can reach as high as HRC60-62°, which places extremely stringent requirements on the wear resistance and cutting edge strength of the cutting tools. Currently, when cutting this material, the linear speed generally needs to be controlled below 120m / min, and the feed per tooth controlled at 0.2mm / t, resulting in extremely low cutting efficiency and unstable tool life. Frequent tool replacements not only increase production costs but also reduce production efficiency, affecting the manufacturing cycle and quality of automotive molds.

[0004] Traditional cutting tools used for automotive mold cutting mainly fall into two categories: standard type (with both primary and secondary cutting edges) and bottom-edge connected type. Standard type tools have evenly distributed cutting edges, with the primary edges connected at the bottom and the secondary edges not connected, and the cutting edge structure has two clearance angles. This structure performs reasonably well when cutting slope features greater than ±15-20°, but it cannot achieve the high efficiency of ultra-dense teeth when cutting features less than ±15-20° or flat features. Furthermore, the conventional two clearance angle structure results in significant tip retraction after tip wear, leading to a decrease in the accuracy of the tool's ball end profile and premature tool life. In addition, the secondary cutting edge has relatively poor strength, and the tip is prone to chipping when cutting high-hardness hardened tool steel (HRC60-62°). Bottom-edge connected type tools have unevenly distributed cutting edges, with all bottom edges connected, and also have a two clearance angle structure. While the ultra-dense teeth at the bottom are highly efficient when cutting flat features, the ball end mill has only one contact point at the cutting edge, resulting in zero linear velocity at the bottom. The ultra-dense tooth distribution at the cutting edge makes chip removal difficult, easily leading to chip buildup and chipping, resulting in unstable tool life. Furthermore, the ball end mill's profile accuracy decreases after the cutting edge wears down. Therefore, inventing a composite-edge, high-efficiency ball end mill with ultra-dense teeth to improve these problems has become a pressing issue for those skilled in the art. Utility Model Content

[0005] To overcome the above shortcomings, this utility model provides a composite-edge high-efficiency ball end mill with ultra-dense teeth. It aims to improve the ball end mill's problem of having only one contact point at the cutting edge, resulting in zero bottom linear velocity, and the cutting edge with ultra-dense tooth distribution being prone to poor chip removal, which in turn leads to chip accumulation and chipping, unstable tool life, and a decrease in ball end profile accuracy after the cutting edge wears down.

[0006] This utility model is achieved as follows: a composite-edge high-efficiency ball-end mill with ultra-dense teeth, comprising...

[0007] The milling cutter body includes a cutter body and a cutting edge assembly. The cutting edge assembly includes cutting edges, which are distributed circumferentially on the outer surface of the cutter body. The cutting edges are unevenly distributed on the cutter body.

[0008] All blades include a cutting edge, the width of which is 1% of the blade diameter, and the cutting edge is distributed at ±75° of the ball head.

[0009] The foremost part of the blade is provided with a blade tip, and there are two blade tips, both of which are located at the foremost part of the blade.

[0010] In a preferred embodiment of this utility model, the two sides of the cutting edge are a rear cutting surface and a front cutting surface, respectively. The front cutting surface contacts the chip and has a concave arc shape.

[0011] In a preferred embodiment of this utility model, the rear cutting face and the front cutting face are provided with a chip-receiving groove at their ends near the cutting edge, and the chip-receiving groove is located between adjacent cutting edges.

[0012] In a preferred embodiment of this utility model, the end of the blade is provided with an end chip groove, which is correspondingly provided on the outer side of the blade tip, and the end chip groove cooperates with the mating chip groove.

[0013] In a preferred embodiment of this utility model, the blades are unequally distributed on the blade body, and two blade tips are designed corresponding to the bottom of the unequally distributed blades.

[0014] In a preferred embodiment of this utility model, the inner walls of the end chip groove and the mating chip groove are polished to achieve a smooth surface.

[0015] In a preferred embodiment of this utility model, the bottom of each blade is arc-shaped, and the blade band is distributed closely to the blade.

[0016] The beneficial effects of this utility model are as follows: This utility model provides a composite-edge high-efficiency ball-end mill with ultra-dense teeth. During use, the unequal distribution of the cutting edges provides space for grinding the two contact points at the bottom, ensuring the stability and wear resistance of the bottom edge during cutting. When the milling cutter rotates to cut automotive mold materials, both cutting edges participate in the cutting simultaneously, forming a stable cutting force distribution, effectively avoiding stress concentration and wear problems caused by zero linear velocity at a single contact point. The cutting edge plays a crucial role in the cutting process. When the tool begins cutting, the cutting edge first contacts the workpiece. Due to its special design of width and angle, it can withstand the cutting force to a certain extent, reducing the initial wear of the cutting edge. As cutting progresses, the cutting edge can inhibit the cutting edge from retreating due to wear, ensuring the accuracy of the ball end profile, thereby guaranteeing the stability of cutting accuracy. For example, when cutting high-hardness materials such as quenched tool steel Cr12MoV, the cutting edge can effectively disperse the cutting force, preventing excessive wear and chipping of the cutting edge. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this utility model and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the milling cutter body structure provided in this embodiment of the utility model;

[0019] Figure 2 A schematic diagram of the blade assembly structure provided for an embodiment of this utility model;

[0020] Figure 3 A top view structural schematic diagram provided for an embodiment of this utility model;

[0021] Figure 4 A schematic diagram of the blade assembly structure provided for an embodiment of this utility model;

[0022] Figure 5 for Figure 3 Enlarged view of section A in the middle.

[0023] In the diagram: 100, end mill body; 110, cutter body; 120, cutting edge assembly; 121, cutting edge; 122, cutting edge band; 123, flank face; 124, rake face; 125, end chip groove; 126, cutter tip; 127, mating chip groove. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0025] Please see Figures 1 to 5 This utility model provides a technical solution: a composite-edge high-efficiency ball end mill with ultra-dense teeth, comprising...

[0026] The milling cutter body 100 includes a cutter body 110 and a cutting edge assembly 120. The cutting edge assembly 120 includes cutting edges 121, which are mounted circumferentially on the outer surface of the cutter body 110 and are unequally distributed on the cutter body 110. Each cutting edge 121 includes a cutting edge 122, the width of which is 1% of the cutting diameter. The cutting edge 122 is distributed at ±75° positions on the ball end. The foremost part of the cutting edge 121 is provided with a cutting tip 126. There are two cutting tips 126, both located at the foremost point of the cutting edge 121. The cutting edge 122 has a smooth surface, a certain degree of hardness and wear resistance, and can effectively suppress the cutting tip retreat caused by tool wear, ensuring the ball end profile accuracy and thus guaranteeing cutting accuracy.

[0027] The cutting edge 121 has a flank face 123 and a rake face 124 on its two sides. The rake face 124 contacts the chip and has a concave arc shape. The concave arc design increases the chip removal space, allowing the chip to move smoothly along the cutting surface and facilitating chip removal. The two clearance angles of the flank face 123 are optimized according to the characteristics of the material being cut to balance the relationship between cutting force and tool wear. It is suitable for cutting materials such as cast iron, ductile iron, and quenched tool steel Cr12MoV in automotive mold manufacturing.

[0028] Please see Figures 3 to 5The flank face 123 and the rake face 124 are provided with matching chip grooves 127 at their ends near the cutting edge 121. The matching chip grooves 127 are located between adjacent cutting edges 121 and can accommodate the chips generated during the cutting process, preventing chip accumulation from affecting the cutting effect. The end of the cutting edge 121 is provided with an end chip groove 125, which is correspondingly located on the outside of the tip 126. The end chip groove 125 and the matching chip groove 127 cooperate with each other to form a continuous chip channel. Its shape and size are adapted to the end chip groove 125 to ensure that the chips can be smoothly discharged from the cutting area. During the cutting process, it directly contacts the workpiece and bears the main cutting force. The design of the tip 126 can ensure efficient cutting under cutting angles of ±15-20° or flat features, and is not prone to wear and chipping.

[0029] The cutting edges 121 are unequally distributed on the cutter body 110, and two cutting tips 126 are designed at the bottom of the unequally distributed cutting edges 121. When the milling cutter rotates and cuts, the two cutting tips 126 can avoid the situation where the linear velocity of a single contact point is zero, effectively improve the wear resistance of the bottom cutting edge, increase the cutting life, and improve the cutting surface quality of the bottom cutting edge. The cutting edges 121 are evenly spaced on the cutter body 110 to avoid instability during rotation.

[0030] The inner walls of the end chip groove 125 and the mating chip groove 127 are polished to make the surface smooth, which reduces the friction of chips in the groove and prevents chips from clogging the chip groove.

[0031] The bottom of the blade 121 is rounded. The blade band 122 is tightly integrated with the blade 121. The material of the blade band 122 is the same as the base material of the blade 121 or is a coating material with higher hardness and wear resistance. The coating thickness is uniform and it is tightly integrated with the base material to further improve the performance of the blade band 122.

[0032] The connection between the cutter body 110 and the milling cutter body 100 adopts a high-precision fitting method, such as an interference fit or a high-precision connecting key, to ensure the installation accuracy and stability of the cutter body 110 on the milling cutter body 100, and to ensure the dynamic balance performance of the milling cutter when rotating at high speed.

[0033] The number and distribution density of the cutting edges 121 are optimized according to the diameter of the milling cutter and the cutting requirements. While ensuring the strength of the tool and the chip space, efficient cutting is achieved and the machining efficiency is improved.

[0034] Working principle: The unequal distribution of the cutting edges 121 provides space for grinding at the two contact points at the bottom, ensuring the stability and wear resistance of the bottom edge during cutting. When the milling cutter rotates to cut automotive mold material, both cutting edges 126 participate in cutting simultaneously, forming a stable cutting force distribution, effectively avoiding stress concentration and wear problems caused by zero linear velocity that may occur at a single contact point.

[0035] The cutting edge 122 plays a crucial role in the cutting process. When the tool begins cutting, the cutting edge 122 first contacts the workpiece. Due to its special design of width and angle, it can withstand cutting forces to a certain extent, reducing initial wear of the cutting tip. As cutting progresses, the cutting edge 122 can suppress the retreat of the cutting tip due to wear, ensuring the accuracy of the ball end profile and thus guaranteeing the stability of cutting accuracy. For example, when cutting high-hardness materials such as hardened tool steel Cr12MoV, the cutting edge 122 can effectively disperse cutting forces, preventing excessive wear and chipping of the cutting tip.

[0036] The concave arc surface design of the rake face 124 guides the chips during their formation. During cutting, the chips are discharged along the tangential direction of the concave arc surface. The shape and curvature of the concave arc surface are optimized according to the cutting parameters and the material being cut, ensuring that the chips leave the cutting area at a suitable angle and speed. Simultaneously, the end chip groove 125 and the mating chip groove 127 provide sufficient space to accommodate the chips. Under the influence of cutting force and their own gravity, the chips enter from the end chip groove 125 and are discharged to the outside of the milling cutter through the mating chip groove 127, preventing chip accumulation on the tool surface.

[0037] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A composite-edge high-efficiency ball-end mill with ultra-dense teeth, characterized in that, include The milling cutter body (100) includes a cutter body (110) and a cutting edge assembly (120). The cutting edge assembly (120) includes cutting edges (121). The cutting edges (121) are distributed along the circumferential direction on the outer surface of the cutter body (110). The cutting edges (121) are unevenly distributed on the cutter body (110). Each blade (121) includes a cutting edge (122), the width of which is 1% of the blade diameter, and the cutting edge (122) is distributed at ±75° of the ball head; The foremost part of the blade (121) is provided with a blade tip (126), and there are two blade tips (126), both of which are located at the foremost part of the blade (121).

2. The composite-edge high-efficiency ball end mill with ultra-dense teeth as described in claim 1, characterized in that: The blade (121) has a rear cutting surface (123) and a front cutting surface (124) on its two sides. The front cutting surface (124) contacts the chip and has a concave arc shape.

3. The composite-edge high-efficiency ball-end mill as described in claim 2, characterized in that: The rear cutting face (123) and the front cutting face (124) are provided with a chip-receiving groove (127) near the end of the cutting edge (121), and the chip-receiving groove (127) is located between adjacent cutting edges (121).

4. The composite-edge high-efficiency ball end mill with ultra-dense teeth as described in claim 3, characterized in that: The end of the blade (121) is provided with an end chip groove (125), which is located on the outside of the blade tip (126). The end chip groove (125) and the matching chip groove (127) cooperate with each other.

5. The composite-edge high-efficiency ball-end mill as described in claim 1, characterized in that: The blades (121) are unequally distributed on the blade body (110), and the two blade tips (126) are designed with two corresponding bottoms of the unequal distribution of the blades (121).

6. The composite-edge high-efficiency ball-end mill as described in claim 4, characterized in that: The inner walls of the end chip groove (125) and the mating chip groove (127) are polished.

7. The composite-edge high-efficiency ball-end mill as described in claim 1, characterized in that: The bottom of each blade (121) is arc-shaped, and the blade band (122) is tightly connected to the blade (121).

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