An assembled enveloping worm gear shaving cutter and a manufacturing method thereof

Abstract

The application relates to an assembled envelope worm gear shaving cutter and a manufacturing method thereof, which comprises a torus cutter body; a plurality of cutter blades which are detachably connected with the torus cutter body and are equally spaced along the circumferential direction of the torus cutter body; the cutter blade comprises a plurality of cutting teeth, the tooth profile parameters of the cutting teeth are matched with the parameters of an actual worm, and the worm workpiece is precisely machined through envelope motion. The application can conveniently realize the effect of envelope worm gear shaving cutter clearance angle machining and reduce the surface roughness of the shaved worm.

Description

Technical Field

[0001] This application relates to the technical field of worm gear machining, and in particular to an assembled enveloping worm gear shaving cutter and its manufacturing method. Background Technology

[0002] Enveloping worm gear drives, relying on their multi-tooth meshing and long contact line structure, exhibit excellent comprehensive performance in high-end equipment fields such as precision machine tools, engineering machinery, and mining equipment, including high load-bearing capacity, high transmission efficiency, low transmission error, smooth operation, and low noise. Currently, the main machining tool for enveloping worm gears is the hob. Due to the limitations of the hob's structure, its cutting edge number is usually less than 13 teeth, resulting in a relatively large surface roughness of the machined worm gear. This leads to problems such as reduced transmission accuracy, decreased load-bearing capacity, and increased transmission noise. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, this application provides an assembled worm gear shaving cutter and its manufacturing method to modify the tooth surface of the worm gear and improve the transmission accuracy.

[0004] Firstly, this application provides an assembled enveloping worm gear shaving cutter, which adopts the following technical solution: An assembled enveloping worm gear shaving cutter includes: a toroidal cutter body; a plurality of blades detachably connected to the toroidal cutter body and evenly spaced along the circumference of the toroidal cutter body; each blade includes a plurality of cutting teeth, the tooth profile parameters of which are matched with the parameters of the actual worm gear, so as to finish the worm gear workpiece through enveloping motion.

[0005] By adopting the above technical solution, a shaving cutter is designed to simulate the envelope motion of an actual worm gear for precision machining of worm wheel workpieces, solving the problems of high surface roughness and low precision after machining with worm wheel hobs. The inserts and toroidal cutter body are detachable, facilitating not only the replacement of worn inserts but also allowing for individual and flexible cutting of inserts. This ensures that all clearance angles are formed simultaneously during insert machining, resolving the issues of low clearance angle grinding efficiency and uncontrollable precision in existing methods. The design of multiple cutting teeth allows each insert to participate in cutting work at different positions, thereby balancing the cutting load and reducing the wear rate of individual cutting teeth. The design of multiple inserts evenly spaced along the circumference of the toroidal cutter body ensures uniform load distribution during cutting, thus extending the service life of the shaving cutter.

[0006] Preferably, the cutting tooth includes a rake face and two side faces, the two side faces being located on the left and right sides of the rake face respectively; the intersection of the side faces and the rake face forms a side cutting edge, which is used to correct the worm gear tooth surface and to extrude and polish the tooth surface after cutting.

[0007] By adopting the above technical solution, the side cutting edge can effectively correct the geometry of the worm gear tooth surface during the cutting process, and at the same time reduce the surface roughness of the worm gear by extruding and finishing the tooth surface.

[0008] Preferably, the cutting tooth includes a first flank face and a second flank face. One end of the first flank face intersects the top of the rake face, and the other end intersects the second flank face. The second flank face is located below the first flank face. There is a gap between the first flank face, the second flank face and the worm gear workpiece to avoid the worm gear workpiece from being exposed during cutting.

[0009] By adopting the above technical solution, the first and second flank faces are designed to avoid friction with the worm gear workpiece during the cutting process, thus preventing wear on the machined surface of the worm gear workpiece and also avoiding tool wear.

[0010] Preferably, the side face and the cutting plane form a side clearance angle, and the angle of the side clearance angle is 3~5°.

[0011] By adopting the above technical solution, the formation of the side clearance angle ensures that only the side cutting edge participates in cutting during the generating motion of the tool, avoiding contact between other parts of the side cutting edge and the cut worm gear tooth surface.

[0012] Preferably, the number of blades is greater than the number of chip grooves in the hobbing cutter during the worm gear workpiece hobbing process.

[0013] By adopting the above technical solution, increasing the number of cutting blades can improve cutting efficiency, while reducing the load on each blade, improving the stability of the cutting process and achieving full break-in, avoiding machining quality problems caused by concentrated load, and extending the overall service life of the shaving cutter.

[0014] Preferably, it further includes a first end cap and a second end cap, the first end cap and the second end cap being respectively connected to the two ends of the toroidal cutter body, for limiting the axial and radial displacement of the plurality of blades and preventing the plurality of blades from detaching from the toroidal cutter body.

[0015] By adopting the above technical solution, the first and second end caps connect the toroidal cutter body and the cutting blade together, preventing the cutting blade from loosening or detaching due to centrifugal force or cutting force during high-speed operation. The limiting effect of the two end caps ensures a tighter connection between the cutting blade and the toroidal cutter body, thereby guaranteeing accuracy and consistency during the cutting process. The detachable structure of the end caps facilitates the replacement and maintenance of the cutting blade, improving assembly efficiency and ease of operation.

[0016] Preferably, the annular blade body includes multiple blade slots, and a slot body is formed between two adjacent blade slots. The blade is inserted into the blade slot. The slot body has a first positioning step at both ends, and the blade has a second positioning step at both ends. The first positioning step and the second positioning step are connected to the first end cap or the second end cap.

[0017] By adopting the above technical solution, the slot body and the cutting blade achieve precise positioning through the cooperation of the positioning steps, ensuring the accurate installation position of the cutting blade on the toroidal blade body, improving assembly accuracy, and enhancing the overall structural stability of the shaving cutter. The combined effect of the first and second positioning steps prevents the cutting blade from shifting or loosening during cutting, thus guaranteeing machining quality. Furthermore, the design of the cutting blade slot facilitates quick cutting blade replacement and maintenance, reducing downtime and improving production efficiency.

[0018] Preferably, the first end cap includes a first sleeve portion, a first locking portion, and a first end head. The first sleeve portion is sleeved on the toroidal cutter body and a plurality of blades. The first end of the toroidal cutter body is provided with a first threaded portion. The first locking portion is connected to the first threaded portion. The first end head is used to connect with a processing device. The second end cap includes a second sleeve portion and a second locking portion. The second sleeve portion is sleeved on the toroidal cutter body and a plurality of blades. The second end of the toroidal cutter body is provided with a second end head and a second threaded portion. The second locking portion is connected to the second threaded portion. The second end head is used to connect with a processing device.

[0019] Using the above technical solutions, the first set of designs features a close fit between the toroidal cutter body and the insert, ensuring overall structural stability during high-speed operation. The first locking part mates with the first threaded part, strengthening the connection between the end cap and the toroidal cutter body and facilitating disassembly and maintenance. The first end connects the tool to the machining equipment, ensuring convenient installation and reliable connection, thus improving machining positioning accuracy. The second design enhances the overall stability of the toroidal cutter body and insert, reducing minute displacements caused by centrifugal force during high-speed cutting. The second locking part and the second threaded part fit tightly, simplifying assembly and disassembly steps and reducing maintenance costs.

[0020] Preferably, the axial ends of the blade are 0.05~0.1mm away from the inner end faces of the first sleeve and the second sleeve, respectively.

[0021] By adopting the above technical solution, the cutting tool can move the insert slightly along the axial direction to compensate for manufacturing errors. During cutting, a slight elastic axial feed displacement is generated, which, in conjunction with radial feed displacement and supplemented by sliding shearing motion, performs slight and uniform cutting on the worm gear tooth surface, removing cutting edges remaining from rough machining and correcting tooth profile errors.

[0022] Secondly, this application provides a method for manufacturing an assembled enveloping worm gear shaving cutter, employing the following technical solution: A method for manufacturing an assembled enveloping worm gear shaving cutter includes the following steps: The toroidal cutter body is machined according to the actual worm gear size requirements and the installation requirements of the machining equipment. The toroidal cutter body is 0.5~1mm smaller than the actual worm gear root size. First end cap and second end cap are also included. Based on the dimensions of the toroidal cutter body and the actual worm gear dimensions, a shaving cutter model is established. The shaving cutter model includes a toroidal cutter body model and multiple blade models. The toroidal cutter body model has multiple blade slots that are adapted to each of the multiple blade models. The multiple blade models are evenly distributed along the circumference of the toroidal cutter body model. Number each insert slot and insert model on the toroidal cutter body model, take out each insert model equally, slot the toroidal cutter body according to the model and mark it with the corresponding number, process each insert according to the insert model and mark it with the corresponding number. Each back angle of the grinding blade; Install each blade into the corresponding blade slot on the toroidal blade body, and perform fine grinding and sharpening on the side blades; Remove each blade and apply a coating. Reinstall the blades into their respective blade slots on the toroidal blade body in numerical order, and lock the first and second end caps to complete the assembled worm gear shaving cutter.

[0023] By adopting the above technical solutions, firstly, high-precision CNC machine tools are used for cutting the toroidal tool body, first end cap, and second end cap to ensure that their dimensional accuracy and surface finish meet the design requirements. Secondly, when modeling the cutting tool, 3D modeling software is used to accurately simulate the geometry and relative position of the insert and insert slot, thereby optimizing the overall structural design of the tool. During the grooving and insert machining process, each insert is precisely matched with its corresponding insert slot through numbering management. This one-to-one matching method not only improves assembly efficiency but also significantly reduces the risk of performance degradation due to assembly errors. In addition, in the step of grinding the back angle of the insert, a special grinding machine is used for multi-axis linkage machining to ensure that the back angle meets the design requirements, while ensuring the cutting performance and heat dissipation capacity of the insert. Coating treatment enhances the hardness and wear resistance of the insert. The selection of coating materials is adjusted according to actual machining needs to adapt to different cutting conditions and worm gear workpiece materials. Finally, in the assembly stage, the inserts are strictly installed back into their corresponding insert slots according to the numbering sequence, and the overall structure is fixed by locking the first end cap and the second end cap. This process not only ensures accurate blade positioning, but also enhances the overall rigidity and stability of the tool through the double-end cap design. Attached Figure Description

[0024] Figure 1 This is a three-dimensional schematic diagram of the assembled worm gear shaving cutter provided in the embodiments of this application.

[0025] Figure 2 This is a radial cross-sectional schematic diagram of the assembled enveloping worm gear shaving cutter provided in the embodiments of this application.

[0026] Figure 3 This is an axial cross-sectional schematic diagram of the assembled enveloping worm gear shaving cutter provided in the embodiments of this application.

[0027] Figure 4 This is a three-dimensional schematic diagram of the blade provided in the embodiment of this application.

[0028] Figure 5 This is another three-dimensional schematic diagram of a blade provided in the embodiments of this application.

[0029] Figure 6 This is a top view schematic diagram of the cutting teeth provided in the embodiments of this application.

[0030] Figure 7 This is a schematic diagram of the toroidal cutter body provided in the embodiments of this application.

[0031] Explanation of reference numerals in the attached drawings: 1. Circular cutter body; 11. First threaded portion; 12. Second threaded portion; 13. Second end; 14. Cutter slot; 15. Slot body; 151. First positioning step; 2. Cutter; 21. Cutting tooth; 211. Front cutting face; 2111. Top cutting edge; 2112. Side cutting edge; 212. First flank cutting face; 213. Second flank cutting face; 214. Side cutting face; 215. Second positioning step; 31. First end cap; 311. First sleeve portion; 312. First locking portion; 313. First end; 32. Second end cap; 321. Second sleeve portion; 3211. Inner end face; 322. Second locking portion. Detailed Implementation

[0032] To better understand the purpose, technical solutions, and advantages of this application, it has been described and illustrated below with reference to the accompanying drawings and embodiments. However, those skilled in the art should understand that this application can be implemented without these details. In some cases, to avoid obscuring various aspects of this application due to unnecessary description, well-known methods, processes, systems, components, and / or circuits already described at a higher level will not be elaborated upon. It will be apparent to those skilled in the art that various modifications can be made to the embodiments disclosed in this application, and the general principles defined in this application can be applied to other embodiments and application scenarios without departing from the principles and scope of this application. Therefore, this application is not limited to the illustrated embodiments, but conforms to the broadest scope consistent with the scope of protection claimed in this application.

[0033] It should be noted that the descriptions of these embodiments are for the purpose of aiding understanding the present invention, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0034] In the description of this application, "several" means one or more, "more than" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. The use of "first" and "second" in the description is merely for distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0035] In the description of this application, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples.

[0036] Existing worm gear enveloping machining tools are mostly hobs. Due to the limitations of the hob's structure, the number of circumferential cutting edges is usually less than 13, resulting in a relatively large surface roughness of the machined worm gear. Typically, after the worm gear is manufactured, it needs to undergo a running-in process to eliminate unavoidable minor errors during machining, improve surface accuracy, and allow the tooth surfaces of the two parts to reach an ideal conjugate state. However, the running-in process increases the manufacturer's production cycle and cost, and is therefore often overlooked. Worm gears that neglect the running-in process generally do not meet the precision requirements of industries such as robotics, solar energy, and CNC machine tools, which have high precision requirements for worm gears. Therefore, the inventors believe that using a shaving process on the machined enveloping worm gear is an effective way to improve its surface quality and transmission performance, as well as save costs. However, currently, there are no suitable shaving tools for enveloping worm gears available domestically or internationally.

[0037] In addition, the back angle grinding of toroidal worm gear hobs is difficult to control and the precision is uncontrollable. More importantly, the cutting tool used in the grinding equipment is a grinding wheel. When the number of chip grooves of the hob exceeds four or the helix angle increases, physical interference easily occurs between the grinding wheel and the hob tooth surface, making it impossible to complete the back angle grinding.

[0038] This application discloses an assembled enveloping worm gear shaving cutter, which is in the shape of a toroidal worm. It is a tool for finishing the tooth profile after hobbing, which can improve the tooth surface quality and precision, is suitable for manufacturing precision worm gears, and reduces production costs.

[0039] Please refer to Figure 1 - Figure 5 The assembled worm gear shaving cutter includes a toroidal cutter body 1 and multiple inserts 2. The toroidal cutter body 1 is manufactured according to the actual worm gear paired with the target worm gear. The multiple inserts 2 are detachably connected to the toroidal cutter body 1, so each insert 2 can be machined independently before being installed on the toroidal cutter body 1. When each insert 2 is machined independently, its clearance angle can be ground using a grinding machine, avoiding interference with the grinding wheel during overall machining. The multiple inserts 2 are distributed circumferentially along the toroidal cutter body 1. Each insert 2 includes multiple trapezoidal cutting teeth 21, which are distributed arc-shaped along the length of the insert 2, i.e., the two ends of the insert 2 are high and the middle is concave. The tooth profile parameters of each cutting tooth 21, such as module and pressure angle, are matched with the parameters of the actual worm gear. The space between two adjacent inserts 2 forms a chip groove, which can accommodate the generated chips and fall off as the toroidal cutter body 1 rotates. The toroidal cutter body can be connected to machining equipment, such as a CNC machine tool, to realize the rotation of the shaving cutter. During the rotation, it simulates the meshing motion of the actual worm and worm wheel workpiece. The worm wheel workpiece is a worm wheel blank with a rotating structure, which has been rough-machined by hobbing.

[0040] like Figure 4 and Figure 5 As shown, each cutting tooth 21 includes a rake face 211 and two side faces 214. The two side faces 214 are located on the left and right sides of the rake face 211, respectively, and both intersect with the rake face 211. The intersection of the side faces 214 and the rake face 211 forms a side cutting edge 2112 that envelops the side surface of the worm gear tooth. The rake face 211 is the main cutting surface for cutting the worm gear workpiece. During the cutting process, chips are generated and are responsible for the flow and curling of the chips. The side cutting edge 2112 is used to correct the tooth profile and, after cutting and correcting the tooth profile, to compress and modify the tooth surface, thereby improving the accuracy of the worm gear tooth surface.

[0041] The cutting tooth 21 also includes a first flank face 212 and a second flank face 213. One end of the first flank face 212 intersects the top of the rake face 211, and the intersection forms the tip edge 2111. The other end of the first flank face 212 intersects the second flank face 213, and the second flank face 213 is located below the first flank face 212, so that the first flank face 212 is inclined downward. There is a gap between the tip edge 2111 and the worm gear workpiece, so that it will not contact the worm gear workpiece during the enveloping motion, so as not to damage the tooth root fillet shape of the worm gear workpiece and ensure finishing. The first and second flank faces 212 and 213 are inclined downwards, providing radial clearance to avoid contact with the worm gear workpiece. Since the tool rotates, without the inclined first and second flank faces 212 and 213, the top of the cutting teeth would directly rub against the machined tooth root. The inclined design of the first and second flank faces 212 and 213 avoids contact with the worm gear workpiece during rotation, preventing wear on the machined surface of the worm gear workpiece, ensuring machining accuracy, and reducing wear on the tool itself. The second flank face 213 connects to the tooth root, supporting the entire cutting tooth 21 and ensuring that the rake face 211 and flank face 214 do not deform or chip when subjected to cutting forces.

[0042] The first flank face 212 is a downwardly inclined surface, and the angle between it and the plane passing through the top cutting edge 2111 (the first clearance angle) can be 2~5°. The second flank face 213 is a downwardly inclined surface, and the angle between it and the cutting plane passing through the top cutting edge 2111 (the second clearance angle) can be 8~15°. The intersection of the first flank face 212 and the second flank face 213 is rounded. The first flank face 212 adopts a small chamfer to ensure the edge strength and cutting stability, while the second flank face 213 adopts a large chamfer to provide sufficient space for envelope movement and chip removal. The two form a stepped double clearance angle structure, which reduces manufacturing costs and extends tool regrinding life while ensuring finishing quality.

[0043] In some implementations, three or more back facets can be provided, and a smooth transition can be achieved by gradually increasing the tilt angle.

[0044] like Figure 6As shown, the side face 214 forms a clearance angle α with the cutting plane, ensuring that only the side cutting edge 2112 contacts the workpiece. The cutting plane is a plane passing through the side cutting edge 2112 and coinciding with the cutting speed direction. The clearance angle α is 3~5°. Since the side cutting edge 2112 needs to continuously and stably remove the finishing allowance of the worm gear tooth side, if the clearance angle is too small (<3°), the side cutting edge is not sharp enough, and friction with the machined tooth surface can easily generate extrusion stripes and work hardening, reducing the surface finish. If the clearance angle is too large (>5°), the side cutting edge is sharper, but the support is insufficient, and micro-vibration marks are easily generated during cutting, which also affects the surface quality. The clearance angle α of 3~5° set in this application allows the side cutting edge 2112 to have sufficient strength to resist intermittent cutting impact while maintaining sharpness.

[0045] In this embodiment, the number of cutting blades is greater than the number of chip grooves on the hob during the hobbing process of the worm gear workpiece. For example, when the worm gear workpiece is rough-machined, a hob is used, which has 13 cutting edges, i.e., 13 chip grooves. The number of cutting blades in the shaving cutter provided in this application is preferably twice the number of chip grooves on the hob, i.e., 26 cutting blades. By increasing the number of circumferential teeth, the envelope density is increased, achieving full envelope of the worm gear workpiece. If the number of circumferential teeth on the shaving cutter is equal to or less than the number of chip grooves in the hobbing process, each tooth needs to remove a large amount of material per revolution, resulting in concentrated cutting force and easy chipping. The design with more teeth makes the cutting amount smaller each time, and the cutting process is smoother. The number of teeth on the shaving cutter is much greater than the number of chip grooves in the hobbing process, which evenly distributes the finishing allowance to multiple cutting teeth, thereby reducing the cutting load of a single tooth, improving the continuity of the envelope motion, avoiding harmonic resonance, and significantly extending the tool regrinding life and machining efficiency.

[0046] The tooth surface of the shaving cutter provided in this application is a spatial envelope surface that is conjugately matched with the tooth surface of the target envelope worm gear. It is designed in reverse based on the meshing relationship between the normal worm and the target envelope worm gear. By setting multiple inserts 2, and the number of inserts 2 is greater than the number of chip grooves of the hob in the hobbing process, full envelope can be achieved, resulting in high machining accuracy. The rake face 211, the second flank face 213, the first flank face 212, and the side face 214 cooperate with each other to ensure tool durability and transmission stability. The side cutting edge 2112 effectively suppresses the generation of residual cutting edges on the tooth surface, significantly improves the tooth surface machining quality, and enhances machining accuracy.

[0047] like Figure 3 and Figure 7As shown, the shaving cutter provided in this application also includes a first end cap 31 and a second end cap 32. The first end cap 31 and the second end cap 32 are located at both ends of the toroidal cutter body 1 and are connected to the toroidal cutter body 1 to prevent multiple blades 2 from detaching from the toroidal cutter body 1. The first end cap 31 includes a first sleeve portion 311, a first locking portion 312, and a first end head 313. The first sleeve portion 311 is sleeved on the toroidal cutter body 1 and the multiple blades 2, which can limit the axial and radial displacement of the blades 2. The first end of the toroidal cutter body 1 is provided with a first threaded portion 11, and the first locking portion 312 is tightly connected to the first threaded portion 11 to ensure a locking effect. The first end head 313 is used to connect to processing equipment, which facilitates the installation and use of the entire shaving cutter. The second end cap 32 includes a second sleeve portion 321 and a second locking portion 322. The working principle of the second sleeve portion 321 is the same as that of the first sleeve portion 311, jointly ensuring the stable installation and efficient cutting of the cutting tool 2. The second end of the toroidal cutter body 1 is provided with a second threaded portion 12 and a second end head 13. The second threaded portion 12 is threadedly connected to the second end cap 32 to achieve locking. The second end head 13 is used to connect to the processing equipment, which is a grinding equipment for processing the enveloping toroidal worm gear tooth surface. This application uses the first end cap 31 and the second end cap 32 to limit the two ends of the cutting tool 2 axially and radially, preventing the cutting tool 2 from disengaging from the toroidal cutter body 1. The first end cap 31 and the second end cap 32 are threadedly connected to the toroidal cutter body 1, facilitating disassembly. The provision of the first end head 313 and the second end head 13 on the first end cap 31 and the toroidal cutter body 1 respectively facilitates quick installation on the processing equipment and improves production efficiency.

[0048] like Figure 7 As shown, the toroidal cutter body 1 is provided with multiple axially extending blade slots 14. These slots are evenly distributed circumferentially around the toroidal cutter body 1, and each slot can be inserted into a corresponding blade 2, enabling detachable installation of the blade 2 and the toroidal cutter body 1. In this embodiment, the blade slot 14 is a straight groove extending through both ends along its length. Its cross-section can be rectangular, inverted T-shaped, or dovetail-shaped, etc. The bottom of the blade 2 is correspondingly shaped to fit the groove, allowing for quick insertion through both ends of the blade slot 14. In other embodiments, the blade slot 14 can be segmented, comprising multiple groove segments arranged axially. Each groove segment can have a rectangular cross-section, facilitating insertion of the blade 2 from top to bottom. At least one groove is provided at each end of the toroidal cutter body 1, allowing the first end cap 31 and the second end cap 32 to lock the blade 2 in place after insertion. When the cutting tooth 21 cuts into the worm gear workpiece, the cutting force attempts to push the insert 2 backward. This backward force will instead lock the insert 2 into the insert slot 14 of the toroidal tool body 1, forming a self-locking mechanism. The greater the cutting force, the more firmly the insert 2 is fixed on the tool body, and the higher the rigidity.

[0049] In this embodiment, multiple blade slots 14 are machined from the tool body using a milling machine to form multiple slot bodies 15. These slot bodies 15 are circumferentially spaced, meaning that the space between two adjacent slot bodies 15 is a blade slot 14. Each slot body 15 has a first positioning step 151 at both ends for connection with an end cap, and the middle area of ​​the slot body 15 is recessed into an arc shape. Each blade 2 has a second positioning step 215 at both ends, and the middle area of ​​the blade 2 is arc-shaped, with the same curvature as the slot body 15, to better accommodate the machining requirements of the worm gear. After the blade 2 is inserted into the blade slot 14, the second positioning steps 215 at both ends are flush with the end faces and circumferential surfaces of the two first positioning steps 151, respectively. Therefore, the first fitting portion 311 and the second fitting portion 321 can simultaneously fit multiple blades 2 and the toroidal tool body 1, serving to position and fix the blades 2.

[0050] like Figure 3 As shown, after the first end cap 31 and the second end cap 32 lock the multiple blades 2 to the toroidal cutter body 1, the distance d between the two ends of the blade 2 in the axial direction and the inner end face 3211 of the first sleeve part 311 or the inner end face 3211 of the second sleeve part 321 is 0.05~0.1mm. That is, the axial length dimension of the blade 2 is 0.05~0.1mm smaller than the dimension defined by the toroidal cutter body 1 and the first sleeve part 311 and the second sleeve part 321. In this embodiment, d=0.05mm is preferred, so that the blade 2 can move slightly in the axial direction to compensate for manufacturing errors. At the same time, a slight elastic axial displacement feed can be generated during the cutting process. Combined with radial displacement feed and sliding shearing motion, a slight uniform cutting is performed on the worm gear tooth surface to remove the cutting edges remaining in the roughing stage and correct the tooth profile error.

[0051] This application also provides a method for manufacturing an assembled enveloping worm gear shaving cutter, comprising the following steps: The toroidal cutter body, first end cap, and second end cap are machined according to the actual worm gear size requirements and the installation requirements of the machining equipment. Based on the dimensions of the toroidal cutter body and the actual worm gear dimensions, a shaving cutter model is established. The shaving cutter model includes a toroidal cutter body model and multiple blade models. The toroidal cutter body model has multiple blade slots that are adapted to each of the multiple blade models. The multiple blade models are evenly distributed along the circumference of the toroidal cutter body model. Number each insert slot and insert model on the toroidal cutter body model, take out each insert model equally, slot the toroidal cutter body according to the model and mark it with the corresponding number, process each insert according to the insert model and mark it with the corresponding number. Each back angle of the grinding blade; Install each blade into the corresponding blade slot on the toroidal blade body, and perform fine grinding and sharpening on the side blades; Remove each blade and apply a coating. Reinstall the blades into their respective blade slots on the toroidal blade body in numerical order, and lock the first and second end caps to complete the assembled worm gear shaving cutter.

[0052] The toroidal cutter body 1 is required to be 0.05-0.1m smaller than the actual worm's 3d normal dimension, and 0.05-0.1m larger than the actual worm's tooth tip and root, where m is the module. This is to compensate for potential errors during material removal, thereby improving the accuracy of the insert 2 profile. The number of inserts 2 is 20-100, with a thickness of 1-5mm, coordinated with the actual worm's module, helix angle, and other parameters. By limiting the number of inserts 2 to 20-100, this application provides sufficient segments to cover the continuous envelope changes of the worm gear tooth surface, achieving full envelope, while avoiding the assembly complexity caused by too many inserts 2. The multi-blade structure reduces the height of residual cutting edges after worm gear tooth surface machining, improving tooth surface roughness. The axial dimension of the insert 2 is 0.05-0.1mm smaller than the dimensions defined by the end caps, forming a floating space where the insert 2 can move slightly axially. This allows the insert 2 to dynamically adjust its position according to the shape errors generated during shaving. This minute displacement, generated according to changes in actual cutting load, not only absorbs vibration energy but also corrects tooth surface contact deviations. Ultimately, it maintains the overall accuracy and cutting stability of the tool by compensating for manufacturing errors. This design transforms manufacturing tolerances into a functional floating mechanism, simplifying assembly process requirements and improving the tool's adaptability and reliability under complex working conditions. The width and number of insert slots 14 match the inserts 2, each insert 2 being unique, its profile determined by the model and its angle. The toroidal tool body must also be installed according to its numbered position sequence. The toroidal tool body 1, as the basic component supporting the inserts 2, can be made of high-strength alloy steel to ensure sufficient rigidity and wear resistance during cutting. The grinding machine can be a CNC tool grinder to achieve precise grinding of each clearance angle. The insert 2 coating treatment can employ AlCrN / TiSiN multilayer coating technology to enhance the surface hardness and wear resistance of the insert 2, extending its service life.

[0053] This application achieves reliable manufacturing of a high-precision worm gear shaving cutter through a systematic process. In the tool body preparation stage, the pre-shrinking design provides compensation space for subsequent assembly, avoiding installation interference caused by manufacturing tolerances. The design of the insert slot 14 enables assembled tools and allows for slight axial movement of the insert 2 to compensate for manufacturing errors. In the modeling stage, a modeling strategy based on enlarged tooth tip and root dimensions, combined with the method of equally dividing and removing the insert 2, ensures that the profile of each insert 2 precisely matches its installation angle on the circumference, fundamentally solving the problem of inconsistency in insert 2 caused by manual operation. Manufacturing the insert 2 based on the model achieves precise digital replication of complex spatial surfaces, eliminating the uncertainty of manual intervention. When grinding each clearance angle using a CNC tool grinder, the trajectory planning capability of the CNC equipment ensures the accurate formation of each clearance angle, effectively replacing the inefficient manual grinding process. In the sharpening step after insert 2 is installed, the finishing grinding of both sides based on the assembled state ensures the geometric accuracy of the cutting edge in the final working position, improving the continuity and consistency of the cutting teeth 21. Finally, the assembly process, based on the design position sequence, ensures that each blade 2 is arranged at a specific angle. The axial constraint when locking the end cap maintains the stability of the overall structure, thereby achieving efficient and reliable manufacturing of the high-precision worm gear shaving cutter.

[0054] This application, based on the principle of spatial conjugate generating, uses a dedicated enveloping worm gear shaving cutter as the cutting tool. Through high-precision multi-axis linkage between the shaving cutter and the worm gear blank, a conjugate meshing relationship consistent with the theoretical enveloping worm pair is established, achieving generating shaving machining. The shaving cutter adopts a conjugate curved surface tooth profile matching the enveloping worm gear, with chip grooves arranged on the tooth surface to form micro-cutting teeth 21. During machining, the shaving cutter and the worm gear blank rotate separately, maintaining a predetermined transmission ratio, center distance, and shaft angle. Simultaneously, radial micro-elastic displacement feed and axial displacement feed are used, supplemented by sliding shearing motion, to perform micro-uniform cutting on the worm gear tooth surface, removing pre-machining residual cutting edges, tooth profile errors, and heat treatment deformation. This improves the accuracy, surface quality, and meshing performance of the enveloping worm gear tooth surface, enabling the worm gear to meet the high-precision requirements of the precision industry without a running-in process after manufacturing, shortening the manufacturer's production cycle and saving costs.

[0055] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. An assembled enveloping worm gear shaving cutter, characterized in that, It is a tool for finishing the tooth profile after hobbing, comprising: a toroidal tool body (1); a plurality of inserts (2) detachably connected to the toroidal tool body (1) and evenly distributed along the circumference of the toroidal tool body (1); the inserts (2) include a plurality of cutting teeth (21), the tooth profile parameters of the plurality of cutting teeth (21) being matched with the parameters of the actual worm gear, so as to finish the worm gear workpiece by enveloping motion, the worm gear workpiece having been rough-machined by hobbing; The cutting tooth (21) includes a rake face (211) and two side faces (214). The two side faces (214) are located on the left and right sides of the rake face (211), respectively. The intersection of the side faces (214) and the rake face (211) forms a side cutting edge (2112), which is used to correct the worm gear tooth surface and squeeze and polish the tooth surface after cutting. It also includes a first end cap (31) and a second end cap (32), the first end cap (31) and the second end cap (32) being connected to the two ends of the toroidal cutter body (1) respectively, for limiting the axial and radial displacement of the multiple blades (2) and preventing the multiple blades (2) from detaching from the toroidal cutter body (1). The first end cap (31) includes a first sleeve portion (311), which is sleeved on the annular cutter body (1) and a plurality of blades (2). The second end cap (32) includes a second sleeve portion (321), which is sleeved on the annular cutter body (1) and a plurality of blades (2). The axial ends of the blades (2) are respectively 0.05~0.1mm away from the inner end faces of the first sleeve portion (311) and the second sleeve portion (321).

2. The assembled enveloping worm gear shaving cutter according to claim 1, characterized in that: The cutting tooth (21) includes a first flank face and a second flank face. One end of the first flank face intersects the top of the front face (211), and the other end intersects the second flank face. The second flank face is located below the first flank face. There is a gap between the first flank face and the second flank face and the worm gear workpiece to avoid the worm gear workpiece during cutting. The angle between the first flank face (212) and the plane passing through the top edge (2111) is 2° to 5°. The angle between the second flank face (213) and the cutting plane passing through the top edge (2111) is 8° to 15°.

3. The assembled worm gear shaving cutter according to claim 2, characterized in that: The side face (214) forms a side back angle with the cutting plane, and the angle of the side back angle is 3~5°.

4. The assembled enveloping worm gear shaving cutter according to claim 1, characterized in that: The number of blades (2) is greater than the number of chip grooves of the hob during the hobbing process of the worm gear workpiece.

5. The assembled enveloping worm gear shaving cutter according to claim 1, characterized in that: The annular blade body (1) includes multiple blade slots (14), and a slot body (15) is formed between two adjacent blade slots (14). The blade (2) is inserted into the blade slot (14). The slot body (15) has a first positioning step (151) at both ends, and the blade (2) has a second positioning step (215) at both ends. The first positioning step (151) and the second positioning step (215) are connected together to the first end cap (31) or the second end cap (32).

6. The assembled enveloping worm gear shaving cutter according to claim 5, characterized in that: The first end cap (31) includes a first locking part (312) and a first end (313). The first end of the annular blade (1) is provided with a first threaded part (11), and the first locking part (312) is connected to the first threaded part (11). The second end cap (32) includes a second locking part (322). The second end of the annular blade (1) is provided with a second end (13) and a second threaded part (12), and the second locking part (322) is connected to the second threaded part (12). The first end (313) and the second end (13) are used to connect to the processing equipment.

7. A method for manufacturing an assembled enveloping worm gear shaving cutter, characterized in that, Including the following steps: The toroidal cutter body (1), the first end cap (31), and the second end cap (32) are processed according to the actual worm size requirements and the installation requirements of the processing equipment. The processing requirements for the toroidal cutter body 1 are that the normal dimension of the 3d of the actual worm is 0.05~0.1m smaller, and the tooth tip and tooth root are 0.05~0.1m larger than the actual worm, where m is the module. Based on the dimensions of the toroidal cutter body (1) and the actual worm gear dimensions, a shaving cutter model is established. The shaving cutter model includes a toroidal cutter body (1) model and multiple blade (2) models. Multiple blade slots (14) are provided on the toroidal cutter body (1) model to match the multiple blade (2) models one by one. The multiple blade (2) models are distributed at equal intervals along the circumference of the toroidal cutter body (1) model. Number each blade slot (14) and each blade (2) model on the toroidal cutter body (1) model, take out each blade (2) model equally, slot the toroidal cutter body (1) according to the model and mark it with the corresponding number, process each blade (2) according to the blade (2) model and mark it with the corresponding number; Grinding blade (2) at each rear angle; Install each blade (2) into the corresponding blade slot (14) of the annular blade body (1), and perform fine grinding and sharpening on the side blades (2112); Remove each blade (2) and apply a coating. Reinstall the blades (2) in the blade slots (14) of the toroidal blade body (1) according to their number positions, and lock the first end cap (31) and the second end cap (32) to complete the assembly-type enveloping worm gear shaving cutter.

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