Milling tool and design method thereof

Abstract

The invention relates to the technical field of milling, and discloses a milling tool and a design method thereof. The milling tool comprises a tool bit and a tool bar which are in threaded connection; a plurality of cutting edges are evenly distributed on the tool bit in the circumferential direction. One axial end of the tool bit is provided with a tool bit interface; a plurality of positioning islands are uniformly distributed on the tool bit interface, a plurality of positioning surfaces formed on the tool bit interface comprise three positioning surfaces to which each positioning island belongs, and the three positioning surfaces are planes and consist of two side surfaces and a middle surface; the side center lines of all the positioning islands extend through the axial center of the tool bit; the side faces of all the positioning islands do not interfere with each other in a radial space during machining; one axial end of the cutter bar is provided with a cutter bar interface; a plurality of positioning grooves matched with the positioning island structures are uniformly distributed in the cutter bar interface; according to the scheme, the limitation brought by an existing positioning island structure is broken through, a milling tool is manufactured by replacing a precision pressing technology with machining, the positioning precision can be continuously kept, the form and position precision is obviously improved, and the continuous machining quality is ensured while the tool performance is improved.

Description

Technical Field

[0001] The invention relates to the technical field of milling processing, and in particular to a milling tool and a design method thereof. Background Art

[0002] The mainstream replaceable cutter head products in the current market abroad widely adopt the parallel symmetrical design of the positioning island's positioning surface, aiming to improve the accuracy and stability of tool installation. This design usually sets two or more parallel and circumferentially evenly distributed positioning islands at the bottom or side of the tool base to ensure that each cutter head can be accurately installed at the same height and plane, achieving uniform cutting load distribution, making the tool more stable during high-speed rotation or cutting, reducing the possibility of vibration and swing, and improving processing accuracy and surface quality.

[0003] However, this design also has significant defects. First, the torque surface is unevenly stressed during the machining process. Since the symmetrical layout of the positioning surface cannot fully compensate for the force difference of the tool in actual use, this not only affects the working efficiency of the tool, but may also shorten the life of the tool bar, especially the life of the tool bar interface. Secondly, there is a problem of mutual interference between the positioning surfaces, and the positioning accuracy cannot be improved by traditional machining methods. This means that manufacturers can only rely on the technology of precision pressing and one-time molding, which limits the preparation of such tool products. At the same time, this method places extremely high demands on pressing equipment and processes, sintering equipment and processes. For example, it is necessary to accurately control the material composition, mold design, pressing parameters and sintering parameters to ensure uniformity and consistency during the molding process, as well as the minimum deformation during the sintering process. This method also brings many challenges: the production process is complex, the technical requirements for designers are high, and the skills requirements for operators are high. Once any slight deviation occurs during the pressing and sintering process, it will directly affect the quality of the final product and may even cause the failure of mass production.

[0004] Therefore, although the parallel and symmetrical design of the positioning surface of the positioning island can meet the tasks of rapid positioning and torque transmission of replaceable head products in some aspects, the above-mentioned defects also limit the promotion and use of such replaceable tool head products. Summary of the invention

[0005] The present invention aims to provide a milling tool and a design method thereof, which breaks through the limitations brought by the existing positioning island structure, optimizes the tool structure, and realizes machining instead of precision pressing technology to manufacture milling tools. It can continuously maintain positioning accuracy, significantly improve shape and position accuracy, and enhance tool performance while further ensuring continuous processing quality.

[0006] The basic solution provided by the present invention is: a milling tool, comprising a screw-connected cutter head and a cutter rod;

[0007] The cutter head is evenly distributed with a plurality of cutting edges along the circumferential direction; one axial end of the cutter head has a cutter head interface for docking with the cutter rod; the cutter head interface is evenly distributed with a plurality of positioning islands to form a plurality of positioning surfaces on the cutter head interface; the plurality of positioning surfaces include three positioning surfaces belonging to each positioning island and the bottom surface of the positioning interface between adjacent positioning islands;

[0008] The three positioning surfaces of each positioning island are planes, consisting of two side surfaces and a middle surface between the two side surfaces; the side center lines of all the positioning islands extend through the axial center of the cutter head; the side surfaces of all the positioning islands do not interfere with each other in radial space during machining;

[0009] One axial end of the tool rod has a tool rod interface for docking with a tool head interface; the tool rod interface is evenly distributed with a plurality of positioning grooves adapted to a plurality of positioning island structures; and a positioning interface upper top surface is provided between adjacent positioning grooves.

[0010] The present invention is based on a milling tool and also provides a design method for the milling tool, the design method comprising:

[0011] S10, force analysis, analyzing the actual torque applied to the tool bar in the cutting state, so as to ensure that the force applied to each point on the side of the positioning groove is uniform, and determine the layout direction of the side of the positioning groove;

[0012] S20, structural design, according to the determined layout direction of the positioning groove side surface and the analysis of the tool head processing method, the structural parameters of the tool head interface positioning island are determined so that all the positioning island sides of the tool head interface do not interfere in the radial space during machining;

[0013] S30, parameter serialization design, based on product application scenario analysis, determines the docking form of the cutter head interface and the tool rod interface when screwing, so as to determine the surface structure and dimensional parameters of all positioning surfaces of the cutter head interface and the tool rod interface.

[0014] The present invention is based on a milling tool and a design method, and also provides a milling tool processing method, the processing method comprising:

[0015] S100, the cutter head blank is pressed and the cutter head blank is pressed and formed by precision mold;

[0016] S200, clamping the cutter head blank, installing the cutter head blank on a special fixture and pre-tightening it with screws, wherein the machining surface of the cutter head interface is away from the special fixture;

[0017] S300, grinding positioning detection, using a probe to detect the height of the tool head blank and the torsion angle of the tool head blank;

[0018] S400, tool head grinding, select the corresponding program to perform tool head machining, all positioning surfaces of the tool head interface and the tool head cutting edge are ground and formed at one time;

[0019] S500, tool bar processing, using a special milling cutter to process the tool bar positioning groove.

[0020] The working principle and advantages of the present invention are:

[0021] Precision pressing one-step molding technology can directly form complex geometric shapes in the mold, ensuring the high consistency and accuracy of each component, which not only improves production efficiency, but also reduces the cumulative errors caused by multiple processes. At the same time, precision pressing can strictly control the composition and performance of materials, ensure the uniformity and consistency during the pressing process, thereby improving the overall quality and service life of the tool. Although precision pressing places extremely high demands on equipment and processes, it meets the needs of modern industry for efficient and precise tools, and has therefore become the first choice for manufacturing high-quality replaceable tool head products.

[0022] Based on this, the positioning island structure of such interchangeable tool head products is designed with the optimization idea of ​​improving the accuracy and stability of tool installation, and is not specifically designed for machining. However, in the actual production process, the precision pressing one-step molding technology has raised the processing threshold, causing great trouble for domestic manufacturers. Therefore, optimizing the tool structure so that it can be machined while ensuring tool performance is of practical significance for the manufacturing of such products.

[0023] This solution overcomes the technical prejudice that such replaceable tool head products can only be manufactured by precision mold pressing to ensure accuracy. By redesigning the tool head and tool rod interface structure, it breaks through the limitations of the existing positioning island structure and realizes machining instead of precision pressing technology to manufacture milling tools. It can continuously maintain positioning accuracy, significantly improve shape and position accuracy, enhance tool performance, and further ensure continuous processing quality.

[0024] Compared with the existing technology, this solution has the following advantages:

[0025] 1. The design of extending the center line of the side surface of the tool head and tool bar positioning surface (i.e. the tool bar force surface) through the axial center makes the torque force on the tool bar interface force surface uniform, and the force deformation at each position of the tool bar force surface is the same. In long-term use, it is conducive to maintaining the positioning accuracy of the tool bar interface and further continuously ensuring the processing quality;

[0026] 2. The radial space on the side of the tool head interface positioning surface does not interfere with each other, which enables the tool head to be machined in a more efficient, economical and easy-to-control machining method, especially for products with a maximum tool head diameter range of 10mm-40mm and a tool rod diameter range of 8mm-20mm. It completely avoids the processing limitations of precision mold pressing, reduces processing costs and processing thresholds, and is conducive to the large-scale production and technological development of such products;

[0027] 3. On the basis of realizing the machining of the cutter head, the cutter head interface and the cutting edge can also be clamped and ground at one time, and all positioning surfaces can be precisely ground. The shape and position accuracy can be controlled within 0.005mm. Compared with the existing precision pressed interface accuracy, the shape and position accuracy of this solution is significantly improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A schematic structural diagram of a milling tool provided by an embodiment of the present invention;

[0029] Figure 2 A schematic diagram of the structure of a cutter head provided by an embodiment of the present invention;

[0030] Figure 3 A schematic diagram of the structure of a knife bar provided by an embodiment of the present invention;

[0031] Figure 4 A schematic diagram of the interface connection between a cutter head and a cutter rod provided in an embodiment of the present invention;

[0032] Figure 5 A flow chart of a design method for a milling tool provided by an embodiment of the present invention;

[0033] Figure 6 A schematic diagram of the forces acting on a milling tool provided by an embodiment of the present invention;

[0034] Figure 7 It is a force diagram of the existing mainstream replaceable tool bar interface;

[0035] Figure 8 A schematic diagram of the force of the tool bar interface provided by an embodiment of the present invention;

[0036] Fig. 9 This is a schematic diagram of the structure of the existing mainstream replaceable cutter head interface;

[0037] Fig.10 A front view of a cutter head provided by an embodiment of the present invention;

[0038] Fig.11 A front view of a knife bar provided by an embodiment of the present invention;

[0039] Fig.12A flow chart of a method for processing a milling tool provided by an embodiment of the present invention;

[0040] Fig.13 A processing schematic diagram of a milling tool provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0041] The following is a further detailed description through specific implementation methods:

[0042] The marks in the drawings of the specification include: screw 101, cutter head 102, cutter bar 103, torque one 104, torque two 105, special fixture 106, first island side one 1, first island middle surface 2, first island side two 3, second island side one 4, second island middle surface 5, second island side two 6, third island side one 7, third island middle surface 8, third island side two 9, positioning interface lower bottom surface one 10, positioning interface lower bottom surface two 11, positioning interface lower bottom surface three 12, retracted groove one 13, retracted groove two 14, retracted groove three 15, retracted groove four 16, retracted groove five 17, retracted groove six 18, cutting edge one 19, cutting edge two 20, cutting edge three 21, cutting edge four 22, cutting edge five 2 3. Cutting edge six 24, first groove side one 201, first groove middle surface 202, first groove side two 203, second groove side one 204, second groove middle surface 205, second groove side two 206, third groove side one 207, third groove middle surface 208, third groove side two 209, positioning interface upper top surface one 210, positioning interface upper top surface two 211, positioning interface upper top surface three 212, internal cooling water spray hole 213, internal threaded hole 214, existing positioning groove side one 301, existing positioning groove middle surface 302, existing positioning groove side two 303, existing positioning island middle surface one 311, existing positioning island middle surface two 312, existing positioning island side two 313.

[0043] Example

[0044] Basically as attached Figure 1 As shown, a milling tool comprises a screw-connected cutter head 102 and a cutter bar 103;

[0045] Specifically, Figure 1 The dotted line shows the axial direction, the cutter head 102 has an axial center hole, the cutter bar 103 has an axial internal threaded hole 214, and the center hole and the internal threaded hole 214 are both adapted to the screw 101 for threading. The screw 101 passes through the center hole of the cutter head 102 and is connected to the internal threaded hole 214 of the cutter bar 103 to achieve the fastening of the cutter head 102.

[0046] like Figure 2 As shown, one axial end of the cutter head 102 has a cutter head interface for docking with the cutter rod 103 .

[0047] The tool head interface is evenly distributed with a number of positioning islands to form a number of positioning surfaces on the tool head interface; the number of positioning surfaces include three positioning surfaces belonging to each positioning island and the lower bottom surface of the positioning interface between adjacent positioning islands; the three positioning surfaces belonging to each positioning island are planes, consisting of two side surfaces and an intermediate surface located between the two side surfaces; the side center lines of all the positioning islands extend through the axial center of the tool head 102; the side surfaces of all the positioning islands do not interfere with each other in the radial space during machining; two inward grooves are symmetrically provided on both sides of the lower bottom surface of each positioning interface of the tool head 102; along the axial direction of the tool head 102, the height of the inward groove is lower than the height of the lower bottom surface of the positioning interface, and the height difference is 0.2-0.5mm. The purpose of designing the inward groove is that when the tool head blank is pressed, the existence of the inward groove will make the adjacent positioning surface material denser and will not form cracks; when grinding the positioning surface, the inward groove can ensure that the bottom of the positioning surface can be cleaned, which does not affect the clamping effect and is more beautiful.

[0048] In this embodiment, three positioning islands are set up with an even distribution of 120°. Due to the limitation of the space size of the tool head interface, designing three is a better choice. Designing fewer positioning islands will lead to reduced positioning accuracy, designing more positioning islands will lead to reduced strength of the tool bar interface, and the positioning surface grinding shape and position accuracy requirements will increase, so three is a suitable choice. Among them, the three positioning surfaces of the first positioning island are respectively the first island side surface 1, the first island middle surface 2, and the first island side surface 23; the three positioning surfaces of the second positioning island are respectively the second island side surface 14, the second island middle surface 5, and the second island side surface 26; the three surfaces of the third positioning island are respectively the third island side surface 17, the third island middle surface 8, and the third island side surface 29.

[0049] The three positioning interface lower bottom surfaces are positioning interface lower bottom surface one 10 , positioning interface lower bottom surface two 11 and positioning interface lower bottom surface three 12 respectively.

[0050] The inward groove 13 and the inward groove 2 14 are symmetrically evenly distributed on both sides of the lower bottom surface 10 of the positioning interface; the inward groove 3 15 and the inward groove 4 16 are symmetrically evenly distributed on both sides of the lower bottom surface 2 12 of the positioning interface; the inward groove 5 17 and the inward groove 6 18 are symmetrically evenly distributed on both sides of the lower bottom surface 3 11 of the positioning interface.

[0051] The cutter head 102 has a plurality of cutting edges evenly distributed along the circumference. In this embodiment, there are six cutting edges, namely, cutting edge 19, cutting edge 20, cutting edge 3 21, cutting edge 4 22, cutting edge 5 23 and cutting edge 6 24. Three positioning islands are connected to three of the six cutting edges in the axial direction to ensure that the positioning islands are below the cutting edges for aesthetic purposes.

[0052] like Figure 3As shown, one axial end of the tool rod 103 has a tool rod interface for docking with a tool head interface; the tool rod interface is evenly distributed with a number of positioning grooves adapted to a number of positioning island structures; specifically, adapted to the positioning island structure, each positioning groove also has three positioning surfaces, consisting of two side surfaces and a middle surface located between the two side surfaces, and a top surface of the positioning interface is provided between adjacent positioning grooves.

[0053] In this embodiment, corresponding to the three positioning island structures, three positioning grooves are evenly distributed at 120°, and the three positioning surfaces of the first groove are respectively the first groove side surface 201, the first groove middle surface 202, and the first groove side surface 203; the three positioning surfaces of the second groove are respectively the second groove side surface 204, the second groove middle surface 205, and the second groove side surface 206; the three positioning surfaces of the third groove are respectively the third groove side surface 207, the third groove middle surface 208, and the third groove side surface 209.

[0054] The three positioning interface upper top surfaces are respectively positioning interface upper top surface 1 210 , positioning interface upper top surface 211 , and positioning interface upper top surface 3 212 .

[0055] The end of the tool rod 103 close to the interface of the tool rod 103 is evenly distributed with three inner cooling water spray holes 213 along the circumferential direction, and the inner thread hole 214 is an ordinary inner thread of M system.

[0056] like Figure 4 As shown, when the cutter head 102 and the cutter rod 103 are screwed together, a positioning island is connected to a positioning groove, and a lower bottom surface of a positioning interface corresponds to an upper top surface of a positioning interface, wherein two side surfaces of the positioning island are fitted with two side surfaces of the corresponding positioning groove, the middle surface of the positioning island does not contact the middle surface of the corresponding positioning groove and has a first gap, and the lower bottom surface of the positioning interface and the upper top surface of the positioning interface do not contact and have a second gap.

[0057] Specifically, Figure 4In the figure, the first positioning island and the first groove are used as examples to illustrate that the side surface 1 of the first island of the cutter head 102 fits with the side surface 203 of the first groove of the tool bar 103, the side surface 23 of the first island of the cutter head 102 fits with the side surface 201 of the first groove of the tool bar 103, the middle surface 2 of the first island of the cutter head 102 does not contact the middle surface 202 of the first groove of the tool bar 103, and the first gap is 0.1mm-0.2mm. The lower bottom surface 10 of the positioning interface of the cutter head 102 and the lower bottom surface 211 of the positioning interface of the tool bar 103 do not contact with the upper bottom surface 1210 of the positioning interface of the tool bar 103 and the upper bottom surface 211 of the positioning interface of the tool bar 103, respectively, and the second gap is 0.1mm-0.2mm. The reason for the fitting design is that the six positioning surfaces of the cutter head 102 (i.e., the six sides of the three positioning islands) have a certain inclination angle in the axial direction, and the inclination angle is 20°-30°. When the cutter head 102 is installed, the cutter head 102 is forced to move downward under the action of the screw preload force, and the six positioning surfaces of the cutter head fit with the corresponding positioning surfaces of the tool rod. Because the positioning surfaces have an inclination angle, the cutter head is locked after the positioning surfaces fit. According to the "six-point positioning principle", the upper and lower gaps are designed to be non-contact, and the interval size is controlled at 0.1mm-0.2mm to ensure that the positioning surface fits sufficiently and give the positioning surface processing a certain error accuracy.

[0058] In this solution, the three positioning surfaces of each positioning island are all planes; the advantage of designing them as planes is that it is convenient for machining and precision control of the interface positioning surfaces, and the plane contact surface is larger, which is more conducive to the transmission of torque during use. The side center lines of all the positioning islands extend through the axial center of the cutter head 102; the side surfaces of all the positioning islands do not interfere in the radial space during machining; the above design reasons are as described in the design method.

[0059] A milling tool in this scheme is formed by structural optimization after in-depth analysis of the structural defects of existing mainstream replaceable tool head products. Based on this, a design method for a milling tool is proposed to complete the design of a milling tool in this scheme.

[0060] Basically as attached Figure 5 As shown, a design method of a milling tool is used to design a milling tool of the above-mentioned scheme; the design method comprises:

[0061] S10, force analysis, analyzing the actual torsional force on the tool bar in the cutting state, so as to determine the layout direction of the side surface of the positioning groove by ensuring that the force on each point on the side surface of the positioning groove is uniform; uniform force means that the force magnitude, direction and force deformation amount of at least three points on the midline of the side surface are the same;

[0062] S20, structural design, according to the determined layout direction of the side of the positioning groove and the analysis of the tool head processing method, the structural parameters of the positioning island of the tool head interface are determined so that all the positioning island sides of the tool head interface do not interfere in the radial space during machining; the structural parameters include the number of positioning islands, the layout form, the angle between the two sides of the positioning islands, the angle between the adjacent sides of two adjacent positioning islands, and the number and layout form of the cutting edges;

[0063] S30, parameter serialization design, based on product application scenario analysis, determines the docking form of the cutter head interface and the tool rod interface when screwing, so as to determine the surface structure and size parameters of all positioning surfaces of the cutter head interface and the tool rod interface; the docking form includes the positioning island, the side and middle surfaces of the positioning groove, the fitting method and non-contact method of the bottom surface of the positioning interface and the top surface of the positioning interface.

[0064] Specifically, based on the serialized design of the cutter head machining edge diameter, width, and shape, different cutter head edge designs and cutter head and tool rod positioning connection features (including the cutter head and tool rod side fitting, the middle surface non-contact and gap, the top surface and the bottom surface of the positioning interface non-contact and gap, etc.) determine the docking form of the cutter head interface and the tool rod interface during screw connection, thereby determining the surface structure and dimensional parameters of all positioning surfaces of the cutter head interface and the tool rod interface.

[0065] like Figure 6 As shown in the force analysis, when the cutter head 102 and the tool bar 103 are screwed together, the screw 101 is pre-tightened and applied with a torque 104 by the wrench, and screws forward axially to the tool bar 103, and stops at the pre-tightened position of the screw 101. The cutter head 102 is tightly fitted with the tool bar 103 under the downward pressure of the screw 101. When the tool is cutting, the reaction force of the processed material forms a torque 2 105, which is transmitted through the cutter head 102 to the two side surfaces of the three positioning islands of the cutter head 102 and the two side surfaces of the three grooves of the tool bar 103 that are fitted to it, that is, the two side surfaces of the positioning island and the two side surfaces of the groove are all stress-bearing surfaces. Figure 6 The first island side 1 and the first groove side 203 are used as examples.

[0066] like Figure 7As shown, the tool bar interface of the existing mainstream replaceable tool head product structure has an existing positioning groove side surface 301, an existing positioning groove side middle surface 302, and an existing positioning groove side surface 303. Through in-depth analysis, it is found that the tool bar interface structure of foreign mainstream products has a center line of the existing positioning groove side surface parallel to its vertical axis and does not point to the axial center of the tool head. Taking the center line of the existing positioning groove side surface 303 as an example, this design is subjected to torsion under cutting state, and the force condition of the entire side surface is simplified to the force condition of three points. The forces at the three points are perpendicular to the force surface 303 with the same magnitude and direction. The force at each point can be decomposed into a force perpendicular to the back direction of the force and a force parallel to the back direction of the force. The magnitude and direction of each decomposed force are different, which directly leads to different force deformation amounts at each position of the tool bar force surface 303 in actual use. In long-term use, it is not conducive to maintaining the positioning accuracy of the tool bar interface.

[0067] Based on this, this scheme is designed as follows Figure 8 As shown, the center line of the side surface of the tool bar interface positioning surface (the side surface 203 is shown as an example) points to the axial center of the cutter head. Under the cutting state, the torque 105 acts on the entire side surface, and the force situation is simplified to the force situation of three points. The three points are perpendicular to the force surface 203, and the magnitude and direction are the same. In actual use, the tool bar force surface (i.e., the side surface of the positioning surface) is the same as the side surface 203 described in this figure, and the force deformation at each position is the same. In long-term use, it is beneficial to maintain the positioning accuracy of the tool bar interface. Correspondingly, the center lines of the side surfaces of the tool head interface positioning surface are designed to point to the axial center of the cutter head at the same time.

[0068] In addition, if Fig. 9 As shown, the positioning island structure of the tool head interface of the mainstream foreign replaceable tool head products includes an existing positioning island middle surface 1 311, an existing positioning island middle surface 2 312, and an existing positioning island side surface 2 313. Such interface positioning surfaces interfere with each other in radial space, and the accuracy cannot be controlled by machining means. Therefore, the interface accuracy can only be ensured by precision pressing. This accuracy meets the requirements, but the technical and production requirements are still relatively high.

[0069] Based on this, this scheme is designed as follows Fig.10 and Fig.11 As shown, this scheme determines the number of positioning islands and whether they are symmetrically distributed on the basis that the midlines of the side surfaces of the tool head interface positioning surfaces all point to the axial center of the tool head 102 at the same time, and determines the relationship between the angle θ1 between the two side surfaces to which each positioning island belongs and the angle θ2 between the two adjacent side surfaces of two adjacent positioning islands, so as to ensure that there is no interference in the radial space when all the positioning island sides are machined.

[0070] In this embodiment, Fig.10As shown, the six positioning surface sides 1, 3, 4, 6, 7, and 9 of the three positioning islands in the cutter head interface design are all force-bearing surfaces, and the midlines of their respective surfaces all point to the axial center of the cutter head; the angle θ1 between the two side surfaces belonging to each of the positioning islands is smaller than the angle θ2 between the two adjacent side surfaces of the two adjacent positioning islands. This angle design is based on the symmetrical design of the positioning islands and ensures that the side surfaces do not interfere with each other in the radial space. The angle θ1 between the contact surfaces of the cutter head interface side surfaces 1 and 3, 4 and 6, and 7 and 9 is 40°-60°, and the corresponding angle θ2 between the contact surfaces 1 and 9, 3 and 4, and 6 and 7 is 60°-80°.

[0071] Correspondingly, such as Fig.11 As shown, the six side surfaces 201, 203, 204, 206, 207, and 209 of the three positioning grooves of the tool rod interface are also force-bearing surfaces, and the midlines of their respective surfaces all point to the axial center of the tool rod 103; the positioning island structure is adapted, and the angle θ1 between the two side surfaces to which each positioning groove belongs is smaller than the angle θ2 between the two adjacent side surfaces of two adjacent positioning islands, and the angle θ1 between the contact surfaces of the side surfaces 201 and 203, 204 and 206, 207 and 209 of the tool rod 103 interface is 40°-60°, and the corresponding angle θ2 between the contact surfaces 201 and 209, 203 and 204, 206 and 207 is 60°-80°.

[0072] The height of the cutter head varies according to the diameter of the cutter head and can be 1mm-2mm. The area of ​​the side of the positioning island and the positioning groove is naturally obtained according to the height of the cutter head, the gap value, and the diameter of the interface.

[0073] like Fig.12 As shown, a method for processing a milling tool is also provided, which is used to process the above-mentioned milling tool; the processing method comprises:

[0074] S100, the cutter head blank is pressed and the cutter head blank is pressed and formed by precision mold;

[0075] S200, clamping the tool head blank, reversely mounting the tool head blank on the special fixture 106 and pre-tightening it by means of the screw 101, wherein the machining surface of the tool head interface is away from the special fixture 106; wherein the special fixture 106 may be a special grinding tool bar handle clamped on a grinding machine;

[0076] S300, grinding positioning detection, using a probe to detect the height of the tool head blank and the torsion angle of the tool head blank;

[0077] S400, tool head grinding, select the corresponding program to perform tool head machining, all positioning surfaces of the tool head interface and the tool head cutting edge are ground and formed at one time;

[0078] In this embodiment, Fig.13As shown, the middle surfaces (i.e., upper top surfaces) 2, 5, and 8 of each positioning island of the cutter head 102 are first processed, and then the two side surfaces of each positioning island of the cutter head are processed with the middle surface as the height reference, i.e., side surfaces 1, 3, 4, 6, 7, and 9, and finally, the cutting edge of the cutter head 102, i.e., tooth shapes 19, 20, 21, 22, 23, and 24, are processed. The corresponding program is configured according to the actual processing requirements and is not limited here.

[0079] This solution can complete all machining of the cutter head through one clamping. The cutter head interface and the cutting edge are clamped and ground into shape in one time, with high shape and position accuracy. This avoids the error expansion caused by the secondary clamping caused by first machining the cutter head interface and then using the interface clamping to machine the cutter head tooth shape in the prior art.

[0080] S500, tool bar processing, using a special milling cutter to process the tool bar positioning groove. The previous process also requires blank pressing, clamping, and top surface detection.

[0081] A milling tool and a design method thereof provided in the present embodiment fully consider the torque force conditions during milling and the limiting factors of the processing method, optimize the structure of the milling tool, and completely avoid the performance limitations and processing limitations of mainstream products. Not only can the performance of the milling tool be improved from the perspective of uniform torque force, but also machining and grinding can be achieved from the design of non-interference of positioning surfaces. For the machining of products with a maximum cutter head diameter range of 10mm-40mm and a tool rod diameter range of 8mm-20mm, the positioning surfaces can be precisely ground to control the shape and position accuracy within 0.005mm, with high shape and position accuracy. At the same time, the processing cost and processing threshold can be greatly reduced, which is conducive to promoting the processing production and technological development of replaceable cutter head products.

[0082] The above is only an embodiment of the present invention. The common sense such as the known specific structure and characteristics in the scheme is not described in detail here. The ordinary technicians in the relevant field are aware of all the common technical knowledge in the technical field of the invention before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply the conventional experimental means before that date. The ordinary technicians in the relevant field can improve and implement the scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for the ordinary technicians in the relevant field to implement this application. It should be pointed out that for the technicians in this field, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent.

Claims

1. A milling tool, characterized in that: It includes a screw-connected cutter head and a cutter bar; The cutter head is evenly distributed with a plurality of cutting edges along the circumferential direction; one axial end of the cutter head has a cutter head interface for docking with the cutter rod; the cutter head interface is evenly distributed with a plurality of positioning islands to form a plurality of positioning surfaces on the cutter head interface; the plurality of positioning surfaces include three positioning surfaces belonging to each positioning island and the bottom surface of the positioning interface between adjacent positioning islands; The three positioning surfaces of each positioning island are planes, consisting of two side surfaces and a middle surface between the two side surfaces; the side center lines of all the positioning islands extend through the axial center of the cutter head; the side surfaces of all the positioning islands do not interfere with each other in radial space during machining; One axial end of the tool rod has a tool rod interface for docking with a tool head interface; the tool rod interface is evenly distributed with a plurality of positioning grooves adapted to a plurality of positioning island structures; and a positioning interface upper top surface is provided between adjacent positioning grooves.

2. A milling tool according to claim 1, characterized in that: The cutter head has an axial center hole, and the cutter rod has an axial internal thread hole. The center hole and the internal thread hole are both adapted to screws for thread connection.

3. A milling tool according to claim 1, characterized in that: When the tool head and tool rod are screwed together, the two side surfaces of the positioning island fit with the two side surfaces of the corresponding positioning groove, the middle surface of the positioning island does not contact the middle surface of the corresponding positioning groove and has a first gap, and the lower bottom surface of the positioning interface does not contact the upper top surface of the corresponding positioning interface and has a second gap.

4. A milling tool according to claim 1, characterized in that: The included angle θ1 between the two side surfaces to which each positioning island belongs is smaller than the included angle θ2 between the two adjacent side surfaces of two adjacent positioning islands.

5. A milling tool according to claim 1, characterized in that: Two inward-retracted grooves are symmetrically arranged on both sides of the lower bottom surface of each positioning interface of the cutter head; along the axial direction of the cutter head, the height of the inward-retracted groove is lower than the height of the lower bottom surface of the positioning interface.

6. A milling tool according to claim 1, characterized in that: The position of the tool rod near the tool rod interface is uniformly distributed along the circumference with a plurality of internal cooling water spray holes.

7. A method for designing a milling tool, characterized in that: Used to design a milling tool according to any one of claims 1 to 6; the design method comprises: S10, force analysis, analyzing the actual torque applied to the tool bar in the cutting state, so as to ensure that the force applied to each point on the side of the positioning groove is uniform, and determine the layout direction of the side of the positioning groove; S20, structural design, according to the determined layout direction of the positioning groove side surface and the analysis of the tool head processing method, the structural parameters of the tool head interface positioning island are determined so that all the positioning island sides of the tool head interface do not interfere in the radial space during machining; S30, parameter serialization design, based on product application scenario analysis, determines the docking form of the cutter head interface and the tool rod interface when screwing, so as to determine the surface structure and dimensional parameters of all positioning surfaces of the cutter head interface and the tool rod interface.

8. A method for designing a milling tool according to claim 7, characterized in that: The uniform force in S10 includes that the force magnitude, direction and force deformation at least three points on the midline of the side are the same; the structural parameters in S20 include the number and layout of positioning islands, the angle between the two side surfaces of the positioning island, the angle between the adjacent side surfaces of two adjacent positioning islands, and the number and layout of cutting edges; the docking form in S30 includes the side and middle surfaces of the positioning island and the positioning groove, and the fitting method and non-contact method of the lower bottom surface of the positioning interface and the upper top surface of the positioning interface.

9. A method for processing a milling tool, characterized in that: A milling tool for processing any one of claims 1 to 6; the processing method comprises: S100, the cutter head blank is pressed and the cutter head blank is pressed and formed by precision mold; S200, clamping the cutter head blank, installing the cutter head blank on a special fixture and pre-tightening it with screws, wherein the machining surface of the cutter head interface is away from the special fixture; S300, grinding positioning detection, using a probe to detect the height of the tool head blank and the torsion angle of the tool head blank; S400, tool head grinding, select the corresponding program to perform tool head machining, all positioning surfaces of the tool head interface and the tool head cutting edge are ground and formed at one time; S500, tool bar processing, using a special milling cutter to process the tool bar positioning groove.

10. A method for processing a milling tool according to claim 9, characterized in that: In S400, the middle surface of each positioning island of the tool head is first processed, and then the two side surfaces of each positioning island of the tool head are processed with the middle surface as the height reference, and finally the cutting edges of the tool head are processed.

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