Lattice structure gear modeling method for filling three-period minimal curved surface and processing device

Abstract

The invention discloses a modeling method and a processing device for a lattice structure gear filled with a three-period minimal curved surface, and the method comprises the following steps: writing an implicit function equation of the three-period minimal curved surface by using Matlab numerical analysis software, and generating an stl format model; using Geomagic reverse modeling software to perform reverse modeling on the three-period minimal curved surface cell elements to produce an stp format model; using Matlab numerical analysis software to generate data points, and importing Proe software to generate a gear model; after operations of mirroring, arraying and the like are carried out on the curved surface cell element model by using SolidWorks, a lattice structure is obtained by using a curved surface thickening command; according to the method, SolidWorks is used for dividing the gear into three parts, namely a gear tooth design area, a hub design area and a spoke design area, the spoke design area intersects with a lattice structure Boolean and then is combined with the gear tooth area Boolean and the hub area Boolean, and therefore the lattice structure gear filled with the three-period minimal curved surface is constructed, and a new thought and method are provided for lightweight design of the gear.

Description

Technical Field

[0001] The present invention relates to the technical field of gear modeling, and particularly relates to a method for modeling a lattice structure gear filled with a triply periodic minimal surface and a processing device therefor. Background Art

[0002] As a core component in the field of mechanical transmission, the lightweight design of gears is of great significance for reducing system energy consumption and improving transmission efficiency. Traditional gear lightweighting means mostly adopt methods such as topology optimization, hollow structure or honeycomb filling, etc. However, such methods often lead to a significant decrease in the bearing strength of gears, or a substantial increase in manufacturing costs due to structural complexity.

[0003] In recent years, triply periodic minimal surfaces (TPMS) have shown great potential in the field of additive manufacturing due to their high specific strength, excellent mechanical properties and natural lightweight topology characteristics. TPMS structures (such as Gyroid, Diamond, etc.) can be accurately described by mathematical functions, providing an innovative direction for the lightweight design of gears.

[0004] However, when adapting the TPMS structure to a component with complex tooth profiles and non-uniform stress characteristics such as gears, significant technical bottlenecks are faced: most modeling software can complete the filling of triply periodic minimal surfaces, but due to the geometric characteristics of triply periodic minimal surfaces, it can only be exported in an uneditable stl format, which is not convenient for subsequent model construction and mesh generation, etc. Therefore, it is not easy for modelers to efficiently generate a gear-TPMS composite structure with both lightweight and functional reliability during the modeling process, restricting the application of this technology in precision transmission components. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to provide a method for modeling a lattice structure gear filled with a triply periodic minimal surface and a processing device therefor, so as to solve the problem that during the modeling process, modelers cannot efficiently generate a gear-TPMS composite structure with both lightweight and functional reliability, restricting the application of TPMS in precision transmission components.

[0006] The present invention is realized through the following technical solutions:

[0007] A method for modeling a lattice structure gear filled with a triply periodic minimal surface, comprising the following steps:

[0008] Step 1: Use Matlab numerical analysis software to write an implicit function equation of the triply periodic minimal surface, generate an image model of a single cell, and export the stl format model of the triply periodic minimal surface through the stlwrite function;

[0009] Step 2: Use Geomagic reverse modeling software to perform reverse modeling on the triply periodic minimal surface cell, and export the stp format model of a single cell;

[0010] Step 3: After performing operations such as mirroring and arraying on the surface cell model generated in Step 2 using SolidWorks, use the surface thickening command to thicken the triply periodic minimal surface to obtain a lattice structure;

[0011] Step 4: Use Matlab numerical analysis software to write the curve equation of the gear profile, generate data points, and import them into Proe software to generate the geometric model of the gear;

[0012] Step 5: Use SolidWorks to divide the gear into three parts: the tooth, the hub, and the spoke design area. After performing a Boolean intersection between the spoke design area and the lattice structure, and then performing a Boolean union with the tooth and hub areas, a lattice structure gear filled with the triply periodic minimal surface is constructed.

[0013] Further defined, Step 1 includes the following implicit function equations of the triply periodic minimal surface:

[0014] P surface = cos(x) + cos(y) + cos(z) = 0

[0015] G surface = cos(x) * sin(yt) + cos(y) * sin(z) + cos(z) * sin(x) = 0

[0016] D surface = cos(x) * cos(y) * cos(z) - sin(x) * sin(y) * sin(z) = 0

[0017] Then establish an interface between Matlab and Geomagic software through the interface file stlwrite.m.

[0018] Further defined, the specific process of reverse modeling in Step 2 is as follows:

[0019] Sub-step 1: Import the stl format of the triply periodic minimal surface cell model into the reverse modeling software Geomagic DesignX;

[0020] Sub-step 2: First execute the correct normal command to correct the axis direction and adjust the model position;

[0021] Sub-step 3: Use the surface cutting command to cut the surface to obtain one-eighth of the surface for convenient subsequent trimming operations;

[0022] Sub-step 4: Use the brush tool to delete the redundant sheet part of one-eighth of the surface;

[0023] Sub-step Five: Construct the boundary of one-eighth of the surface, that is, generate its contour boundary;

[0024] Sub-step Six: Sketch the 3D contour of the surface with a spline curve and obtain the surface using the traditional boundary fitting command;

[0025] Sub-step Seven: Extend the surface;

[0026] Sub-step Eight: Perform sketching and lofting on the front, top, and right faces;

[0027] Sub-step Nine: Trim the surface to obtain the solid structure of one-eighth of the surface;

[0028] Sub-step Ten: Mirror and perform Boolean operations, output the obtained cell entity in stp format, and complete the reverse modeling of the stl format cell.

[0029] Further defined, the specific process of the third step is: Write the tooth profile equation of the gear using Matlab. This equation includes the tooth profile equation of a standard involute gear or other complex tooth surface equations, then generate a curve, and import the data points into Proe software to generate the gear geometric model, and then import the gear geometric model into Solidworks.

[0030] Further defined, the specific process of the fourth step is: Use the scale command in Solidworks to modify the size of the cell to obtain the cell with the required size, and then obtain the surface lattice structure through linear array, and set the surface thickening to obtain the periodic array lattice structure.

[0031] Further defined, the specific process of the fifth step is: Divide the gear into three parts: teeth, hub, and design area. Use the move command in direct editing to adjust the position of the design area and the periodic array lattice structure. The spoke lattice structure after Boolean intersection is then Boolean merged with the hub and tooth areas to complete the modeling of the lattice structure gear filled with a three-period minimal surface.

[0032] A processing device for performing the modeling method of a lattice structure gear filled with a three-period minimal surface, including a frame and a ball-end mill and a hobbing cutter installed on the frame. A fixing member for fixing the blank is slidably connected to the frame. The ball-end mill and the hobbing cutter are respectively located on the sliding trajectory of the blank. The ball-end mill is arranged to be lifted on the frame and can approach or move away from the sliding trajectory of the blank through lifting. The hobbing cutter is rotatably connected to the frame.

[0033] Further defined, the top surface of the frame is an arc surface and forms a structure with a semicircular longitudinal section. The top surface of the frame is also provided with a plurality of tooth parts evenly distributed along the circumferential direction. A transmission gear meshing with the tooth parts is arranged on the frame. The transmission gear is rotatably connected to the fixing member;

[0034] A chute extending in the circumferential direction thereof is formed in the side wall of the frame, a slider is slidably connected in the chute, and the slider is rotatably connected to the end of the transmission gear.

[0035] Further defined, the fixing member includes a support seat for supporting the blank gear on the top surface, a plug rod and a positioning piece. A slot extending downward is formed in the top surface of the support seat, and a jack is formed in the side wall of the slot;

[0036] A limiting piece is arranged at the upper end of the plug rod, a through hole opposite to the slot is arranged at the lower end, the positioning piece is slidably arranged in the through hole, an elastic support member is arranged in the through hole, and two ends of the elastic support member are respectively connected to the inner wall of the through hole and the end of the positioning piece. The through hole and the positioning piece both extend upward, and the positioning piece extends outside the plug rod.

[0037] Further defined, a base is rotatably connected to the bottom surface of the support seat, a motor is fixedly arranged on the bottom surface of the base, and the output end of the motor is connected to the middle part of the bottom surface of the support seat.

[0038] The beneficial effects of the present invention are as follows:

[0039] By generating an image model of a single cell, performing reverse modeling on the triply periodic minimal surface cell, and then through mirroring, arraying and surface thickening, a lattice structure is obtained. Then, the lattice structure and the spoke design area of the gear are constructed into a lattice structure gear filled with triply periodic minimal surfaces through Boolean operation, providing a new idea for the lightweight design of the gear. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] The drawings of the present invention are described as follows:

[0041] Figure 1 It is a curved surface cell diagram of three kinds of TPMS of the present invention;

[0042] Figure 2 It is a reverse modeling triply periodic minimal surface model diagram of the present invention;

[0043] Figure 3 It is a model diagram from the curved surface cell to the lattice structure of the present invention;

[0044] Figure 4 It is a schematic diagram of each area of the gear of the present invention;

[0045] Figure 5 It is a schematic diagram of the lattice structure gear of the present invention;

[0046] Figure 6 It is a model diagram of the lattice structure gear with different cells of the present invention;

[0047] Figure 7Flow chart of the modeling method of the lattice structure gear filled with a three - period minimal surface according to the present invention;

[0048] Figure 8 Structural schematic diagram of the processing device according to the present invention;

[0049] Figure 9 Structural schematic diagram of the fixing member according to the present invention;

[0050] Figure 10 Structural schematic diagram of the cooperation between the insertion rod and the support seat for fixing the gear blank according to the present invention.

[0051] In the figure:

[0052] 1. Frame; 2. Ball - end milling cutter; 3. Hobbing; 4. Fixing member; 401. Support seat; 402. Insertion rod; 403. Positioning piece; 5. Tooth part; 501. Transmission gear; 502. Sliding groove; 503. Slide block; 6. Limiting piece; 7. Elastic support member; 8. Base; 9. Gear blank. Detailed implementation manners

[0053] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0054] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention.

[0055] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0056] In the above description of the present invention, it should be noted that the orientation or positional relationship indicated by terms such as "one side", "the other side", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the invention product is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation of the present invention. In addition, terms such as "first", "second", etc. are only used for descriptive distinction and cannot be understood as indicating or implying relative importance.

[0057] In addition, terms such as "identical" do not require the components to be absolutely the same, but there can be slight differences. The term "vertical" only means that the positional relationship between components is more vertical relative to "parallel", and does not mean that the structure must be completely vertical, but can be slightly inclined.

[0058] Please refer to Figures 1-10 , the present invention provides a technical solution: a method for modeling a lattice structure gear with triply periodic minimal surface filling, including the following steps:

[0059] Step 1: Use Matlab numerical analysis software to write the implicit function equation of the triply periodic minimal surface, generate the image model of a single cell, and export the stl format model of the triply periodic minimal surface through the stlwrite function;

[0060] Step 2: Use Geomagic reverse modeling software to perform reverse modeling on the triply periodic minimal surface cell, and export the stp format model of a single cell;

[0061] Step 3: After performing operations such as mirroring and arraying on the surface cell model generated in Step 2 using SolidWorks, use the surface thickening command to thicken the triply periodic minimal surface to obtain a lattice structure;

[0062] Step 4: Use Matlab numerical analysis software to write the curve equation of the gear profile, generate data points, and import them into Proe software to generate the geometric model of the gear;

[0063] Step 5: Use SolidWorks to divide the gear into three parts: tooth, hub, and spoke design areas. After performing a Boolean intersection of the spoke design area with the lattice structure, and then performing a Boolean union with the tooth and hub areas, a lattice structure gear filled with a triply periodic minimal surface is constructed.

[0064] The gear in this solution can be a spur gear with a module of 3.5 mm and 20 teeth, and its main parameters are shown in Table 1:

[0065] Table 1. Main parameters of the gear

[0066]

[0067] In this embodiment, the first step includes the following implicit function equations of the triply periodic minimal surface:

[0068] P surface = cos(x) + cos(y) + cos(z) = 0

[0069] G surface = cos(x) * sin(yt) + cos(y) * sin(z) + cos(z) * sin(x) = 0

[0070] The D surface = cos(x)*cos(y)*cos(z) - sin(x)*sin(y)*sin(z) = 0

[0071] Then, establish the interface between Matlab and Geomagic software through the interface file stlwrite.m.

[0072] In this solution, use Matlab numerical analysis software to write a program for generating a triply periodic minimal surface model. To verify the feasibility and generality of the program, establish the cell models of three triply periodic minimal surfaces, namely the P surface, G surface, and D surface as shown below, Figure 1 and then establish the interface between Matlab and Geomagic software through the interface file stlwrite.m, and output the model in stl format.

[0073] In this embodiment, the specific process of reverse modeling in the second step is as follows:

[0074] Sub-step one: Import the stl format of the triply periodic minimal surface cell model into the reverse modeling software Geomagic DesignX.

[0075] Sub-step two: First, execute the command to correct the normal vector, adjust the model position by correcting the axis direction.

[0076] Sub-step three: Use the surface cutting command to cut the surface to obtain one-eighth of the surface, which is convenient for subsequent trimming operations.

[0077] Sub-step four: Use the brush tool to delete the redundant sheet body part of one-eighth of the surface.

[0078] Sub-step five: Construct the boundary of one-eighth of the surface, that is, generate its contour boundary.

[0079] Sub-step six: Outline the 3D contour of the surface with a spline curve, and use the traditional boundary fitting command to obtain the surface.

[0080] Sub-step seven: Extend the surface.

[0081] Sub-step eight: Draw sketches and perform lofting on the front, top, and right three faces.

[0082] Sub-step nine: Trim the surface to obtain the solid structure of one-eighth of the surface.

[0083] Sub-step ten: Mirror and perform Boolean operations, output the obtained cell solid in stp format, and complete the reverse modeling of the stl format cell.

[0084] In this solution, use Geomagic reverse modeling software to perform reverse modeling on the triply periodic minimal surface cell, as shown below Figure 2The reverse modeling of the P-surface stl model is as follows:

[0085] Sub-step 1: Import the P-surface cell model in the generated triply periodic minimal surface into the reverse modeling software Geomagic DesignX;

[0086] Sub-step 2: First, execute the command to correct the normal vector, adjust the axis direction, and then adjust the model position;

[0087] Sub-step 3: Obtain one-eighth of the surface through the surface cutting command to facilitate subsequent trimming and reverse modeling operations;

[0088] Sub-step 4: Use the brush tool to delete the redundant sheet part of the one-eighth surface;

[0089] Sub-step 5: Construct the boundary of the one-eighth surface, that is, its contour boundary;

[0090] Sub-step 6: Sketch the 3D contour of the surface with a spline curve, and use the traditional boundary fitting command to obtain the surface;

[0091] Sub-step 7: Use the command to extend the surface at the surface boundary to extend the boundary surface;

[0092] Sub-step 8: Perform sketching and lofting on the front, top, and right three faces;

[0093] Sub-step 9: Trim the surface to obtain the solid structure of the one-eighth surface;

[0094] Sub-step 10: Use the mirror and Boolean merge commands to establish a complete surface cell, and output the obtained P-surface cell entity in stp format, thus completing the reverse modeling of the P-surface cell.

[0095] In this embodiment, the specific process of the third step is as follows: Use Matlab to write the tooth profile equation of the gear. This equation includes the tooth profile equation of a standard involute gear, or it can also be other complex tooth surface equations. Then generate a curve, and import the data points into the Proe software to generate the gear geometric model, and then import this gear geometric model into Solidworks.

[0096] In this solution, by using Matlab to write the tooth profile curve equation of the gear, a point cloud data set of the tooth profile curve with the gear parameters shown in Table 1 is generated, and this data set is imported into the Proe software to generate the tooth profile curve. Use the boundary blend command to connect the tooth profile curves to obtain the tooth profile surface model of the gear. Enclose the tooth profile surface of a single tooth to generate a single tooth entity, and then use the circular pattern command with the number of patterns set to 20. After Boolean merging each single tooth entity, a complete gear geometric model is obtained, and then this gear geometric model is imported into Solidworks.

[0097] In this embodiment, the specific process of step four is as follows: Use the scale command in Solidworks to modify the size of the unit cell to obtain a unit cell with the required size, and then obtain a curved surface lattice structure through linear array. Set the thickening of the curved surface to obtain a periodic array lattice structure.

[0098] In this solution, use the scale command in Solidworks to modify the size of the unit cell. In this embodiment, a P-surface unit cell of 10×10×10 mm can be used, and then a curved surface lattice structure is obtained through linear array as Figure 3 (b) shown. The number of arrays in the horizontal and vertical directions can be controlled according to the size of the design area. To control the porosity of the designed lattice structure gear to be 20%, set the thickness of the curved surface thickening to 1.40 mm, and the obtained periodic array lattice structure is as Figure 3 (c) shown. The size and thickness of the unit cell of the lattice structure can be adjusted according to the porosity of the designed lattice structure gear. The porosity is the proportion of the reduced volume of the lattice structure gear in the volume of the normal gear. Therefore, the degree of freedom of the lightweight design of the gear is improved.

[0099] In this embodiment, the specific process of step five is as follows: Divide the gear into three parts: teeth, hub, and design area. Use the move command in direct editing to adjust the position of the design area and the periodic array lattice structure. The spoke lattice structure after Boolean intersection is then Boolean merged with the hub and tooth areas to complete the modeling of the lattice structure gear filled with a three-period minimal surface.

[0100] In this solution, use the split command in SolidWorks to split the gear into three parts: teeth, hub, and spoke design area. After using the move command to align the center point of the spoke design area with the center point of the lattice structure, then Boolean intersect the two to obtain the lattice structure of the spoke area, and then Boolean merge it with the tooth and hub areas to construct a lattice structure gear filled with a three-period minimal surface. To verify the generality of the method, a lattice structure gear model filled with a G-surface is designed using this method, as Figure 6 shown.

[0101] A processing device for implementing a method for modeling a lattice structure gear filled with a three-period minimal surface includes a frame 1, a ball-end milling cutter 2 and a hobbing cutter 3 mounted on the frame 1. A fixing member 4 for fixing a blank 9 is slidably connected to the frame 1. The ball-end milling cutter 2 and the hobbing cutter 3 are respectively located on the sliding trajectories of the blank 9. The ball-end milling cutter 2 is arranged to be lifted on the frame 1 and can approach or move away from the sliding trajectory of the blank 9 by lifting. The hobbing cutter 3 is rotatably connected to the frame 1.

[0102] In this solution, the ball-end milling cutter 2 is located on the sliding track of the plane of the blank 9, while the hobbing cutter 3 is located on the sliding track of the curved surface of the blank 9. Among them, a perforation runs through the middle of the blank 9 from top to bottom.

[0103] The specific usage method is as follows:

[0104] Step 1: Install the blank 9 on the fixing member 4 to fix the two.

[0105] Step 2: By driving the positioning member to slide, drive the blank 9 to the machining area where the ball-end milling cutter 2 is located. At this time, the designed area of the blank 9 faces the direction where the ball-end milling cutter 2 is located.

[0106] Step 3: Use the ball-end milling cutter 2 to cut and drill the designed area of the blank 9, so as to process the designed area of the blank 9.

[0107] Step 4: After processing the blank 9 with the ball-end milling cutter 2, drive the positioning member to slide to the machining area where the hobbing cutter 3 is located. At this time, the tooth area of the blank 9 faces the direction where the hobbing cutter 3 is located.

[0108] Step 5: Drive the hobbing cutter 3 to rotate with a motor and make the tooth area of the blank 9 contact with the hobbing cutter 3, so as to process the tooth area of the blank 9.

[0109] The ball-end milling cutter 2 is installed on the machine frame 1 through a slide rail, so that the ball-end milling cutter 2 can slide along the thickness direction of the machine frame 1. At the same time, in cooperation with the fixing member 4 sliding along the length direction of the machine frame 1 and the ball-end milling cutter 2 being arranged to be lifted on the machine frame 1, it is convenient for the ball-end milling cutter 2 to cut and drill the designed area of the blank 9 on the fixing member 4.

[0110] In this embodiment, the top surface of the machine frame 1 is an arc surface and forms a structure with a semicircular longitudinal section. The top surface of the machine frame 1 is also provided with a plurality of tooth parts 5 evenly distributed along the circumferential direction. A transmission gear 501 meshing with the tooth parts 5 is arranged on the machine frame 1, and the transmission gear 501 is rotatably connected with the fixing member 4;

[0111] A chute 502 extending along the circumferential direction of the machine frame 1 is opened on the side wall of the machine frame 1. A slider 503 is slidably connected in the chute 502, and the slider 503 is rotatably connected with the end of the transmission gear 501.

[0112] In this solution, since the top surface of the frame 1 is semi-circular and there are also a plurality of tooth portions 5 arranged along its circumferential direction on the top surface of the frame 1, when the transmission gear 501 rotates, through the meshing of the transmission gear 501 and the tooth portion 5, it can displace along the circumferential direction of the top surface of the frame 1. During the displacement process of the transmission gear 501, since the slider 503 is connected to the transmission gear 501, the slider 503 displaces synchronously and in the same direction in the chute 502. In this way, through the cooperation of the slider 503 and the chute 502, the transmission gear 501 can stably displace through the tooth portion 5.

[0113] Among them, a motor can be set to be connected to the transmission gear 501 to drive the transmission gear 501 to rotate, so that the transmission gear 501 and the tooth portion 5 cooperate to displace.

[0114] In this embodiment, the fixing member 4 includes a support seat 401 for supporting the gear blank 9 on the top surface, a plug rod 402 and a positioning piece 403. A slot extending downward is opened on the top surface of the support seat 401, and a jack is opened on the side wall of the slot;

[0115] A limiting piece 6 is arranged at the upper end of the plug rod 402, a through hole opposite to the slot is arranged at the lower end, the positioning piece 403 is slidably arranged in the through hole, an elastic support member 7 is arranged in the through hole, and both ends of the elastic support member 7 are respectively connected to the inner wall of the through hole and the end of the positioning piece 403. The through hole and the positioning piece 403 both extend upward, and the positioning piece 403 extends outside the plug rod 402.

[0116] In this solution, the overall longitudinal section of the positioning piece 403 is in an "L" shape. Its upper end is outside the plug rod 402, and its lower end abuts against the elastic support member 7. When the elastic support member 7 is in a natural stretched state, under its elastic action, the positioning piece 403 is pushed towards the direction of the through hole, so that the surface of the positioning piece 403 away from the elastic support member 7 penetrates outside the through hole;

[0117] During use, place the gear blank 9 on the support seat 401, align the central through hole with the slot on the support seat 401, and then insert the plug rod 402 through the gear blank 9 and into the slot. At this time, the bottom surface of the limiting piece 6 at the upper end of the plug rod 402 is in contact with the top surface of the gear blank 9.

[0118] During the insertion process, the end of the positioning piece 403 located outside the through hole is squeezed by the inner wall of the slot and contracts towards the through hole, and the elastic support member 7 is squeezed. When the through hole is aligned with the jack, the elastic support member 7 releases elastic force and pushes the positioning piece 403 towards the direction of the jack, so that the positioning piece 403 is inserted into the jack, thereby positioning the plug rod 402 and fixing it on the support seat 401. And since the gear blank 9 is located between the limiting piece 6 and the support seat 401, and at the same time the plug rod 402 penetrates through the central through hole of the gear blank 9 and the outer wall of the plug rod 402 abuts against the inner wall of the through hole, the gear blank 9 is fixed.

[0119] Among them, a driving motor is arranged between the support base 401 and the transmission gear 501. The driving motor is connected to the transmission gear 501, and the output end is connected to one side of the support base 401. The support base 401 can be driven to turn through the output end of the driving motor, so that the support base 401 can be turned to a suitable angle to facilitate the processing of the blank 9 by the ball-end milling cutter 2 and the hob 3.

[0120] In this embodiment, the bottom surface of the support base 401 is rotatably connected to a base 8, and a motor is fixedly arranged on the bottom surface of the base 8. The output end of the motor is connected to the middle part of the bottom surface of the support base 401.

[0121] In this solution, the motor is fixedly connected to the bottom surface of the base 8, and its output end passes through the base 8 and is connected to the bottom surface of the support base 401. Therefore, the support base 401 can be driven to rotate by the motor. When the tooth region of the blank 9 contacts the hob 3, the support base 401 is driven to rotate by the motor, thereby driving the blank 9 to rotate synchronously. Furthermore, the contact surface between the tooth region of the blank 9 and the hob 3 changes due to the rotation of the blank 9, so as to process the tooth region of the blank 9.

[0122] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the spirit and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. A method for modeling a lattice structure gear with a three-periodic minimal surface, characterized in that: The following steps are involved: Step 1: Use Matlab numerical analysis software to write the implicit function equation of the three-periodic minimal surface, generate the image model of a single cell, and export the stl format model of the three-periodic minimal surface through the stlwrite function; Step 2: Use Geomagic inverse modeling software to reverse model the three-periodic minimal surface cell and export the STP format model of a single cell; Step 3: Use SolidWorks to mirror and array the surface cell model generated in step 2, and then use the surface thickening command to thicken the three-periodic minimal surface to obtain a lattice structure; Step 4: Use Matlab numerical analysis software to write the curve equation of the gear profile, generate data points, and import them into Proe software to generate the gear geometry model; Step 5. Use SolidWorks to divide the gear into three parts: the tooth, the hub, and the spoke design area. After the spoke design area is intersected with the lattice structure Boolean, it is Boolean merged with the tooth and hub areas to construct a lattice structure gear filled with three-periodic minimal surfaces.

2. The method for modeling a lattice structure gear with a filled three-periodic minimal surface according to claim 1, characterized in that: The step 1 includes the following implicit function equations of three periodic minimal surfaces: P surface=cos(x)+cos(y)+cos(z)=0 G surface=cos(x)*sin(yt)+cos(y)*sin(z)+cos(z)*sin(x)=0 D surface=cos(x)*cos(y)*cos(z)-sin(x)*sin(y)*sin(z)=0 Then establish the interface between Matlab and Geomagic software through the interface file stlwrite.m.

3. The method for modeling a lattice structure gear with a filled three-periodic minimal surface according to claim 1, characterized in that: The specific process of reverse modeling in step 2 is as follows: Sub-step 1: Import the stl format of the three-periodic minimal surface cell model into the reverse modeling software Geomagic Design X; Sub-step 2: First, execute the correct normal command to correct the direction of the coordinate axis and adjust the model position; Sub-step 3: Use the surface cutting command to cut the surface to obtain one-eighth of the surface, which is convenient for subsequent trimming operations; Sub-step 4: Use the brush tool to delete the extra slice part of one-eighth of the surface; Sub-step 5: construct the boundary of the one-eighth surface, i.e. generate its contour boundary; Sub-step 6: Use spline curves to outline the 3D contour of the surface, and use traditional boundary fitting commands to obtain the surface; Sub-step 7: Extend the surface; Sub-step 8: Sketch and lay out the front, top and right faces; Sub-step nine: trim the surface to obtain a solid structure of one eighth of the surface; Sub-step 10: Mirror and perform Boolean operations to output the obtained cell entity in stp format and complete the reverse modeling of the cell in stl format.

4. The method for modeling a lattice structure gear with a filled three-periodic minimal surface according to claim 1, characterized in that: The specific process of step three is: use Matlab to write the gear tooth profile equation, which includes the standard involute gear tooth profile equation, or other complex tooth surface equations, and then generate a curve, and import the data point into the Proe software to generate a gear geometry model, and then import the gear geometry model into Solidworks.

5. The method for modeling a lattice structure gear with a filled three-periodic minimal surface according to claim 1, characterized in that: The specific process of step 4 is: using the scaling command in Solidworks to modify the size of the cell to obtain the cell of the required size, and then obtaining the surface lattice structure through the linear array, setting the surface thickening, that is, obtaining the lattice structure of the periodic array.

6. The method for modeling a lattice structure gear with a filled three-periodic minimal surface according to claim 1, characterized in that: The specific process of step five is: divide the gear into three parts: gear teeth, hub, and design area; use the move command in direct editing to adjust the position of the design area and the periodic array lattice structure; and Boolean merge the spoke lattice structure with the hub and gear tooth area after Boolean intersection, thereby completing the modeling of the lattice structure gear filled with three-periodic minimal surfaces.

7. A processing device for executing the lattice structure gear modeling method of filling three-periodic minimal surfaces as described in claims 1-6, characterized in that: The invention comprises a frame (1) and a ball-end milling cutter (2) and a gear hob (3) mounted on the frame (1); a fixing member (4) for fixing a tooth blank (9) is slidably connected to the frame (1); the ball-end milling cutter (2) and the gear hob (3) are respectively located on the sliding track of the tooth blank (9); the ball-end milling cutter (2) is lifted and arranged on the frame (1) and can be moved closer to or farther from the sliding track of the tooth blank (9) by lifting and lowering; and the gear hob (3) is rotatably connected to the frame (1).

8. A processing device according to claim 7, characterized in that: The top surface of the frame (1) is an arc surface and forms a structure with a semicircular longitudinal section. The top surface of the frame (1) is also provided with a plurality of teeth (5) evenly distributed along the circumferential direction. The frame (1) is provided with a transmission gear (501) meshing with the teeth (5). The transmission gear (501) is rotatably connected to the fixing member (4). A sliding groove (502) extending in the circumferential direction of the frame (1) is provided on the side wall thereof, a sliding block (503) is slidably connected in the sliding groove (502), and the sliding block (503) is rotatably connected to the end of the transmission gear (501).

9. A processing device according to claim 7 or 8, characterized in that: The fixing member (4) comprises a support seat (401) whose top surface is used to support the tooth blank (9), an insertion rod (402) and a positioning piece (403); a slot extending downward is provided on the top surface of the support seat (401), and a plug hole is provided on the side wall of the slot; A limiting plate (6) is provided at the upper end of the insertion rod (402), and a through hole opposite to the slot is provided at the lower end. The positioning plate (403) is slidably arranged in the through hole. An elastic support member (7) is arranged in the through hole. The two ends of the elastic support member (7) are respectively connected to the inner wall of the through hole and the end of the positioning plate (403). The through hole and the positioning plate (403) both extend upward, and the positioning plate (403) extends to the outside of the insertion rod (402).

10. A processing device according to claim 9, characterized in that: The bottom surface of the support seat (401) is rotatably connected to a base (8), the bottom surface of the base (8) is fixedly provided with a motor, and the output end of the motor is connected to the middle part of the bottom surface of the support seat (401).

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