Parameterization design method for brake disc tool

Abstract

The invention discloses a brake disc tool parameterization design method, and belongs to the technical field of brake disc machining, the brake disc tool parameterization design method comprises design of a brake disc casting and a model, and the model forms a cavity part of the brake disc casting; a riser is designed; designing a cap caliber; designing a pouring system; creating other brake discs by utilizing the expression; wherein the other brake discs refer to brake discs with different sizes and the same structure; and generating a part diagram. According to the parameterization design method for the brake disc tool, all drawings such as a casting and a process tool can be rapidly designed only by inputting the product size, and by converting a 3D drawing into a 2D drawing, tedious standard search and operation are reduced, the design error rate is reduced, and waste of molten iron is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of brake disc processing, and in particular to a parametric design method for brake disc tooling. Background Art

[0002] Traditional casting tooling is mostly designed with CAD 2D software, which is cumbersome and labor-intensive, and requires rich experience, especially riser design. If the design is unreasonable, either shrinkage defects will occur in the casting, or the riser design will be too large, wasting molten iron. With the improvement of 3D modeling technology, 3D technology has gradually been applied in the field of casting tooling design, making tooling design three-dimensional and more vivid.

[0003] CAM (Computer-Aided Manufaturing) is a method of using computer software to control, manage and automate the manufacturing process. The compatibility of CAD and CAM software data formats (such as IGES, STEP, STL, etc.) enables the transfer of design data between different software. CAD software parametric design is a good solution, which enables changes to be quickly updated and automatically reflected in the CAM system.

[0004] Casting process design is cumbersome and complex, involving a large amount of geometry and parameters. It is a complex task to accurately transfer this data from one system to another. The traditional design method of casting process is to design casting tooling and other drawings with two-dimensional drawings. Different data formats are used between software. CAM operators will write programs based on two-dimensional drawings (3D drawings need to be redrawn), which wastes time and is prone to errors.

[0005] The automobile brake disc is a rotating part with a simple structure, but each product has different specifications and sizes. Each brake disc requires tooling design, the product development cycle is long, the level of designers is uneven, the error rate is high, the quality of castings is unstable, and there is serious waste of molten iron.

[0006] There are many factors to consider in the design of sand casting tools. To design a low-cost, high-quality casting process, it requires considerable experience and a lot of manual calculations, which is a lot of work. In addition, there are few engineers and technicians in the process tooling design in our country, and many companies do not attach importance to the training of talents in this area, resulting in serious waste of molten iron and increased casting costs.

[0007] Models with similar outer diameters of brake discs are grouped together, and the templates and gating systems are universal, with only different model parts being designed. This saves design time for templates and gating systems, and shortens the development cycle. However, the biggest problem with this solution is that castings of different weights use the same gating system, and the pouring time varies greatly. For light castings, the gating system is too large, resulting in a waste of molten iron; for heavy castings, the pouring time is too long, which is prone to casting defects, and errors are still prone to occur during the design process.

[0008] Therefore, the present invention provides a brake disc tooling parameterized design method. Summary of the invention

[0009] The present invention aims at solving the deficiencies in the prior art and provides a method for parameterized design of brake disc tooling.

[0010] The technical solution of the present invention to solve the above technical problems is as follows:

[0011] A parametric design method for a brake disc tooling comprises the following steps:

[0012] S1: brake disc casting and pattern design, wherein the pattern forms the cavity portion of the brake disc casting;

[0013] S2: Riser design;

[0014] S3: Riser diameter design;

[0015] S4: gating system design;

[0016] S5: Use the expression to create other brake discs; the other brake discs refer to brake discs with different sizes and the same structure;

[0017] S6: Generate component diagram.

[0018] Furthermore, the specific steps of S1 include:

[0019] S11: Start the UG program and create a new component file;

[0020] S12: Select the Insert / Modeling command to enter the Modeling module;

[0021] S13: Select the Rotate / Sketch command, use the coordinate plane XY-XZ as the sketch plane, and draw a sketch;

[0022] S14: Establish an expression. First, select a brake disc product. According to the brake disc casting, model drawings and shapes, name several key dimensions of the brake disc as D1, D2, D3, D4, H1, H2, and H3, where D1, D2, D3, and D4 are the diameters of the brake disc at different positions; H1, H2, and H3 are the heights of the brake disc at different positions; enter relevant values ​​in the expression respectively;

[0023] S15: Use expressions to change and indicate relevant dimensions, reduction, allowance, and draft angle on the sketch; the machining allowance is determined according to the diameter D1, and the draft angle is determined according to the height dimension;

[0024] S16: Add constraints to the sketch, select the sketch outlines of the casting and model respectively, and create the casting and model with shrinkage;

[0025] S17: Calculate the mass, volume and area of ​​the casting;

[0026] S18: Establish product association design between components and draw casting and model drawings;

[0027] Furthermore, in S2, the riser is designed by the casting modulus, and the riser size is calculated by the modulus method. The calculation formula of the riser modulus is as follows:

[0028]

[0029] M m =1.2M z ;

[0030]

[0031] R=3.2M Z ;

[0032] Where M Z V is the casting modulus; 铸件 is the casting volume; S 铸件 is the surface area of ​​the casting; R is the riser radius, M m is the riser modulus;

[0033] The liquid metal contained in the feed riser is used to compensate for the shrinkage of the casting when cooling from the pouring temperature to the solidus and during solidification. The shrinkage rate of gray cast iron is 2%, while the utilization rate of the cylindrical feed riser is 15%. The minimum size of the feed riser is determined by the following formula:

[0034] 15% × V 补缩冒口 ≥2%×V 铸件 , where V 补缩冒口 is the volume of the shrinkage riser, V铸件 is the casting volume;

[0035] When the riser radius meets the above conditions, take the maximum value. Create a reference plane according to the riser position. The reference plane is perpendicular to the parting surface and the center line of the cross runner. On this reference plane, a riser sketch is formed by the riser width B, the riser diameter and the riser center position. Through the stretch command, draw the 3D drawings of the upper and lower parts of the riser respectively. The height of the upper riser is 1.8*R, and the draft angle is 2°. The height of the lower riser is 1.2*R, and the draft angle is 5°.

[0036] Furthermore, in order to increase the shrinkage compensation effect of the riser, the modulus size is 0.6 times of the casting, the riser diameter length is 0.3 times of the riser radius, and the riser diameter modulus is calculated according to the cuboid modulus, and the formula is as follows:

[0037]

[0038] M J =0.6M m =0.6×1.2M z =0.72M z ;

[0039] Therefore, the riser width b is calculated as:

[0040] b=5.625M z ;

[0041] Where M J is the riser diameter modulus; b is the riser diameter width; M Z M is the casting modulus; m is the riser modulus;

[0042] Draw a riser sketch based on the riser width b and the riser shape, and use the stretch command to draw a 3D diagram of the riser.

[0043] Furthermore, the pouring system is used to introduce molten iron and fill the mold cavity with the molten iron within a specified time, and the pouring system includes a straight runner, a cross runner and an inner runner.

[0044] Furthermore, in order to ensure the smooth filling of molten iron, the cross-sectional area of ​​the pouring system and the cross-sectional area of ​​each component of the pouring system are as follows:

[0045] F 直 : F 阻 : F 横 : F 内 =1.1:1:1.4:1.2;

[0046] in:

[0047]

[0048] G=G z / 85%;

[0049]

[0050]

[0051] F 直 =πf 2 ;

[0052] In the formula, F 直 is the straight cross-sectional area; F 阻 F is the cross-sectional area of ​​the runner at the flow-blocking part; 横 is the cross-sectional area of ​​the runner; F 内 is the cross-sectional area of ​​the ingates; G is the weight of the molten iron flowing through the flow-blocking section, including the sum of the weights of the casting, runner, ingates, and risers; G z is the casting mass; H is the height of the pouring pressure head;

[0053] K is the resistance area coefficient. For cast iron, K is 1036; m is the shape coefficient of the resistance pouring system. According to the shape of the resistance section, it is taken as 0.6; a is the width of the inner runner; t is the pouring time; and f is the radius of the straight runner.

[0054] In summary, compared with the prior art, the above technical solution has the following beneficial effects:

[0055] (1) The present invention provides a parametric design method for brake disc tooling, which only requires inputting product dimensions to quickly complete the design of all drawings such as castings and process tooling, and converts 3D drawings into 2D drawings, thereby reducing cumbersome standard searches and calculations, reducing design error rates, and reducing the waste of molten iron;

[0056] () The present invention provides a brake disc tooling parametric design method, in which process parameters are easy to modify, which is conducive to optimizing process design and can quickly perform process simulation to achieve the best process and the lowest cost;

[0057] (3) The present invention provides a parametric design method for brake disc tooling, which uses data to draw drawings, facilitates the management and analysis of design data, and is conducive to the development of the foundry industry towards digitalization and intelligence. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] Figure 1 It is a structural schematic diagram of a brake disc casting process according to an embodiment of the present invention;

[0059] Figure 2 is a schematic diagram of a 3D structure in an embodiment of the present invention;

[0060] Figure 3 It is a cross-sectional view of the sprue, runner, ingates, and riser diameters in the embodiment of the present invention;

[0061] Figure 4 It is a schematic diagram of the structure of the upper sand box mold, the lower sand box mold and the template in an embodiment of the present invention;

[0062] Figure 5 Schematic diagram of the structure of the template, pouring cup, pouring seat, etc. in the embodiment of the present invention;

[0063] Figure 6 This is a schematic diagram of an expression before parameter changes in an embodiment of the present invention;

[0064] Figure 7 Schematic diagram of expression after parameter change in an embodiment of the present invention;

[0065] Figure 8 Schematic diagram of temperature field and mass simulation in an embodiment of the present invention.

[0066] Explanation of the accompanying reference numerals: 1. pouring cup; 2. pouring seat; 3. pouring nest; 4. runner; 5. ingode; 6. riser; 7. riser diameter; 8. casting; 9. sprue; 10. upper box sand mold; 11. lower box sand mold; 12. template. DETAILED DESCRIPTION

[0067] The principles and features of the present invention are described below in conjunction with all the accompanying drawings. The examples given are only used to explain the present invention and are not used to limit the scope of the present invention.

[0068] The embodiment of the invention discloses a parametric design method for a brake disc tooling.

[0069] Reference Figure 1-Figure 8 , a brake disc tooling parametric design method, comprising the following steps:

[0070] S1: brake disc casting and pattern design, wherein the pattern forms the cavity portion of the brake disc casting;

[0071] S2: Riser 6 design;

[0072] S3: Riser diameter 7 design;

[0073] S4: gating system design;

[0074] S5: Use the expression to create other brake discs; the other brake discs refer to brake discs with different sizes and the same structure;

[0075] S6: Generate component diagram.

[0076] The present invention adopts the parametric design of brake discs, and carefully designs a set of standard templates in advance, inputs the design standards, requirements, parameters, etc. into the software, and when designing similar structural models, there is no need for manual calculation, data and standard checking, etc. The designer only needs to input the product size value to automatically complete the process tooling design, which makes it easier to design and optimize the process, reduces the error rate, and greatly improves the efficiency. In addition, through parametric design, some casting information can be automatically obtained, such as process yield, sand iron ratio, sand consumption, etc., to provide relevant and accurate data for casting engineering technology, production, finance and other personnel.

[0077] The casting drawing is based on the product drawing with the addition of allowance and draft angle. The model forms the casting cavity part. If the model and the template 12 are designed separately, it is necessary to increase the positioning stop to cooperate with the template 12.

[0078] Reference Figure 1 The casting process diagram includes a pouring cup 1 and a sprue 9, a pouring seat 2, a pouring nest 3, a runner 4, an inner pouring channel 5, a riser 6, a riser diameter 7, and a casting 8.

[0079] First create the template:

[0080] (1) Design of casting drawings and model drawings;

[0081] The casting drawing is a drawing that reflects the actual size and shape of the casting, and is the main basis for casting production and acceptance of castings. The casting drawing adds margins and draft angles on the basis of the product drawing. The model forms the casting cavity. If the model and template are designed separately, the model needs to add positioning stoppers to match the template.

[0082] The steps for designing a 3D drawing of a casting in S1 are as follows:

[0083] S11: Start the UG program, create and name a file;

[0084] S12: Select [Insert] / [Modeling] command to enter the modeling module;

[0085] S13: Select the [Rotate] / [Sketch] command, and draw a sketch using the coordinate plane XY-XZ as the sketch plane;

[0086] S14: In the expression, several key dimensions of the brake disc are named according to the brake disc product casting, model drawings and shapes: the diameters are D1, D2, D3, and D4, and the heights are H1, H2, and H3. In the template case shown in the embodiment of the present invention, the dimensions of the diameters are D1 = 214.3 mm, D2 = 126.3 mm, D3 = 61 mm, and D4 = 137 mm, H1 = 12 mm, H2 = 40.4 mm, and H3 = 5.6 mm;

[0087] Other parameters, such as shrinkage S, draft angles x1, x2, x3, x4, radius r of riser 6, width a of entrapment 5, width b of riser 7, width c of runner 4, radius f of sprue 9 and allowance are all calculated based on the formula set according to product size or standard. Among them, the machining allowance is determined according to the size of the brake disc (D1), and the draft angle is determined according to the height dimension, etc. Figure 1 , a schematic diagram showing the diameter and height.

[0088] S15: Use expressions to change and indicate relevant dimensions, reduction, allowance, and draft angle on the sketch; the machining allowance is determined according to the diameter D1, and the draft angle is determined according to the height dimension;

[0089] S16: Add constraints to the sketch to ensure that the geometry and dimensions are fully constrained. Click the [Finish Sketch] command, then select the sketch outlines of the casting and model respectively, and use the [Rotate] command to create 3D drawings of the casting and model, and create castings and models with shrinkage.

[0090] S17: Calculate the mass, volume and area of ​​the casting. Specifically, use the [Measure] command to measure the mass, volume, area, etc. of the casting;

[0091] S18: Establish product association design between components and draw casting and model drawings. Specifically, use the [Assembly] / [WAVE Geometry Linker] command to establish the association drawing design between components and create related parts drawings.

[0092] (II) Design of sprue and riser position

[0093] Determine the positions of the sprue 9 and riser 6, and then use the stretch, rotate and other commands to create the relevant 3D drawings of the riser 6, riser diameter 7, ingates 5, runner 4, gate nest 3, gate seat 2, sprue 9 and gate cup 1 in sequence.

[0094] In order to convert the sand-iron ratio, 3D upper and lower sand mold drawings are created. Templates and other drawings can also be created. As needed, all casting drawings can be created under the same model, which is equivalent to assembly drawings.

[0095] For example, the 3D drawings created in this case include process drawings, and 3D drawings such as models, templates 12, castings 8, upper sand molds 10, and lower sand molds 11 will also be created.

[0096] This top-down parametric design strategy using sketches makes it easy to arrange the positions of castings and pouring systems, process modifications, etc. on the template. Because dimensions and parameters are interrelated, after completing a set of parametric template designs, they need to be repeatedly verified. Then, the Wave association technology in NX software can be used to model related parts, and parameterization can also be used to automatically generate process cards and other related process files.

[0097] After the template is created, other discs with similar structures but different sizes can be created by simply entering product parameters. For example: a brake disc has diameters of D1 = 247.3, D2 = 133.5, D3 = 66, D4 = 143.3, H1 = 18, H2 = 28, H3 = 6.2. Enter the corresponding data in the expression and the corresponding 3D diagram will be automatically generated after updating.

[0098] The main function of the riser is to compensate for shrinkage. Reasonable design of the riser size is of great significance to obtain dense qualified castings. The riser in the embodiment of the present invention belongs to a side dark hot riser. The side dark hot riser is an auxiliary component used in the casting process, mainly used to avoid defects in the casting. It provides additional molten metal by adding a supplementary part above or on the side of the casting, thereby ensuring that the casting is fully compensated for shrinkage during the solidification process and reducing defects such as shrinkage cavities and shrinkage porosity.

[0099] There is no unified basis for riser size design. Some determine the riser size according to the casting modulus, and some determine it according to the diameter of the casting hot spot. However, most of them use the casting modulus to design the riser. In this case, the modulus method is used to calculate the riser size. The riser structure shape is related to the radius. As long as the structure is the same, the riser modulus and radius are linearly related. The riser size can be calculated by simply calculating the riser radius.

[0100] Furthermore, in S2, the riser is designed by the casting modulus, and the riser size is calculated by the modulus method. The calculation formula of the riser modulus is as follows:

[0101]

[0102] M m =1.2M z ;

[0103]

[0104] R=3.2M Z ;

[0105] Where M Z V is the casting modulus; 铸件 is the casting volume; S 铸件 is the surface area of ​​the casting; R is the riser radius, M m is the riser modulus;

[0106] Among them, the generally accepted rectangular section modulus is:

[0107] (1) Calculation of riser modulus: The calculation of modulus for different geometric shapes in the casting manual is shown in Table 1. Since h≤2.5D (actually 3R), the cylindrical part formula is selected, where D is 2*R and h is the total height of the riser 3R (1.8R+1.2R). Substitute it into the resulting formula (where the upper and lower 2 are divided, which is equivalent to replacing the original diameter with the radius).

[0108] (2) In order to compensate for the shrinkage of the casting, the riser must solidify later than the casting, so 1.2 times the casting modulus is used. The 1.2 is determined based on empirical values.

[0109] (3) The formula for the modulus of a casting is based on the concept of modulus, which is volume divided by surface area.

[0110] Table 1 Calculation of modulus of simple geometric shapes

[0111]

[0112] Since the brake disc is required to have no shrinkage defects inside, the riser modulus is generally larger. In the embodiment of the present invention, 1.2 times the casting modulus is selected. The casting modulus can be automatically calculated by the software to obtain the casting volume and surface area, and the riser radius can be calculated as follows:

[0113] R=3.2M Z ;

[0114] In addition, the liquid metal contained in the feed riser is used to compensate for the shrinkage of the casting when cooling from the pouring temperature to the solidus and during solidification. The shrinkage rate of gray cast iron is 2%, while the utilization rate of the cylindrical feed riser is 15%. The minimum size of the feed riser is determined by the following formula: 15% × V 补缩冒口 ≥2%×V 铸件 , where V 补缩冒口 is the volume of the shrinkage riser, V铸件 is the casting volume;

[0115] When the riser radius meets the above conditions, take the maximum value. Create a reference plane according to the riser position. The reference plane is perpendicular to the parting surface and the center line of the cross runner. On this reference plane, a riser sketch is formed by the riser width b, the riser diameter and the riser center position. Through the stretch command, draw the 3D drawings of the upper and lower parts of the riser respectively. The height of the upper riser is 1.8*R, and the draft angle is 2°. The height of the lower riser is 1.2*R, and the draft angle is 5°.

[0116] (III) Riser diameter design

[0117] Furthermore, in order to increase the shrinkage compensation effect of the riser, the modulus size is 0.6 times of the casting, the riser diameter length is 0.3 times of the riser radius, and the riser diameter modulus is calculated according to the cuboid modulus, and the formula is as follows:

[0118]

[0119] M J =0.6M m =0.6×1.2M z =0.72M z ;

[0120] Therefore, the riser width b is calculated as:

[0121] b=5.625M z ;

[0122] Where M J is the riser diameter modulus; b is the riser diameter width; M Z M is the casting modulus; m is the riser modulus;

[0123] Draw a riser sketch based on the riser width b and the riser shape, and use the stretch command to draw a 3D diagram of the riser.

[0124] (IV) Casting system design

[0125] The pouring system is used to introduce molten iron and fill the mold cavity with molten iron within a specified time, and has the function of blocking sand and slag. The pouring system includes a straight runner 9, a horizontal runner 4 and an inner runner 5. If the pouring time is too long, defects such as cold shut and insufficient pouring are likely to occur. If the pouring time is too fast, defects such as pores, sand holes and slag holes are likely to occur. Therefore, the pouring time is calculated according to the following empirical formula. For example, for a 9kg casting, according to The minimum pouring time calculated by the formula is 6.6 seconds, and the general design takes an integer of 6 seconds.

[0126] Furthermore, in order to ensure the smooth filling of molten iron, the cross-sectional area of ​​each component of the pouring system is as follows:

[0127] F 直 :F 阻 :F 横 :F 内 =1.1:1:1.4:1.2;

[0128] in:

[0129]

[0130] G=G z / 85%

[0131]

[0132]

[0133] F 直=πf 2 ;

[0134] In the formula, F 直 is the straight cross-sectional area; F 阻 Cross-sectional area of ​​the runner at the flow-blocking part; F 横 is the cross-sectional area of ​​the runner; F 内 is the cross-sectional area of ​​the ingates; G is the weight of the molten iron flowing through the flow-blocking section, including the sum of the weight of the casting, runner, ingates, and risers (automatically calculated); G z is the casting weight (automatically measured); H is the height of the pouring pressure head (determined according to the height of the upper box); 85% means that the runner and riser account for about 15% of the casting weight, and the pouring time is calculated based on 15%;

[0135] K is the flow resistance area coefficient. For cast iron, K is 1036; m is the shape coefficient of the flow resistance pouring system, which is determined according to the shape of the flow resistance section and is generally 0.3 to 0.6. In the embodiment of the present invention, it is 0.6; a is the width of the inner runner; t is the pouring time (calculated based on the mass of molten iron passing through the flow resistance section); f is the radius of the straight runner.

[0136] The computer software automatically calculates the casting mass, volume and area, selects the parameters such as the cross-sectional ratio of each component according to the standard and experience, and calculates the pouring time t and the flow resistance area F. 阻 , straight runner radius f, ingentrant width a, etc. Use modeling commands such as [Stretch] and [Rotate] to model runner 4 and ingentrant 5 respectively.

[0137] (V) Using expressions to create other brake discs

[0138] Expressions play an important role in parametric design. Their main functions are:

[0139] (1) Control size and features;

[0140] (2) Establishing relationships between parameters;

[0141] (3) Realize the design intent of engineering and technical personnel;

[0142] (4) Facilitate modification, improve modification and optimize process efficiency;

[0143] (5) It can automatically calculate and solve equations;

[0144] (6) Facilitate data management;

[0145] In this case, four single-disc models with the same structure but different diameters and heights are randomly selected and input into the expression, as shown in Table 2:

[0146] Table 2 Expression

[0147]

[0148]

[0149] The data of the four models in this case are all determined by one design standard. In addition to the product structure dimensions that can be changed (forming different castings), parameters such as the design to the pouring system can also be changed using other design standards (or empirical values), which requires modifying the correlation coefficient in the formula. If the design standard (or empirical value) is changed, the software will automatically update other data of the relevant quantity, including data that is automatically calculated or measured.

[0150] In fact, the formula cannot be changed generally, but the coefficient can be changed through empirical values. The coefficient in the formula is not fixed and can be continuously optimized through design and simulation software (entering different standard parameter values ​​(empirical values) will form different casting 3D drawings, pouring system 3D drawings, and sand mold 3D drawings, etc., and then converted into STL format and input into the simulation software for simulation, and the best parameter value is taken).

[0151] For example:

[0152] The following uses the model "Specification 2" in the case as an example:

[0153] If the casting of this model has shrinkage during simulation and production verification, the improvement measures are as follows:

[0154] To enlarge the riser, the riser coefficient should be increased from 1.2 to 1.3;

[0155] Modification method: Enter the assembly drawing expression in the modeling state (press ctrl+e), change the riser radius R (mm), formula: IF(8 / 3*1.2*Mz<(Rmin)^(1 / 3))(Rmin)ELSE(8 / 3*1.2*Mz) to 1.3. After the change, R=IF(8 / 3*1.3*Mz<(Rmin)^(1 / 3))(Rmin)ELSE(8 / 3*1.3*Mz).

[0156] After the update, the software automatically updates the expression and 3D diagram, so one of the advantages of parametric design is that it can quickly optimize the process and simulate. Figure 6 As shown, the changed expression is Figure 7 The optimized and improved expression (because the riser is enlarged and greater than Rmin, R takes the maximum value of 26.4. Because the riser is enlarged, the total amount of molten iron increases, and related parameters such as process yield and sand-iron ratio are also automatically updated accordingly).

[0157] (VI) Generate component diagram

[0158] Parametric design is a top-down design method. Modeling starts in the assembly environment, which is convenient for arranging castings and pouring systems on the template. The size and process modification are convenient because many dimensions and parameters are interrelated. A change in one dimension may cause many corresponding changes in dimensions, so all sketch dimensions must be constrained. After the template is completed, it is repeatedly verified. After completing a set of parametric template designs, it is equivalent to an assembly. If a 2D drawing of a component is required, a new model is created, and the template drawing that has been formed is added in [Assembly-Add]. Use the [WAVE Geometry Linker] command to select the corresponding component, and then use the [Replace Reference Set] command to remove unnecessary entities. The [Application Module-Drawing] command generates the required 2D drawing.

[0159] Use UG's wave function to create a series of parts based on parameter changes in the assembly drawing. After completing the parametric design, each time the parameter is changed, the assembly drawing automatically generates a 2D drawing of the parts (a top-down design).

[0160] (VII) Verification and testing

[0161] The 3D solid images of castings, gating systems and risers designed with four parameters are divided into different groups and converted into STL format for export. The MAGMA software is used to simulate the shrinkage of casting thermometers through the steps of model creation, meshing, parameter setting, simulation calculation and result demonstration. Figure 8 ,It can be seen from the figure that in the late stage of solidification, the riser is the area with the highest temperature. After cooling, the casting quality meets the design ,requirements.

[0162] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A parametric design method for brake disc tooling, characterized in that: The steps include: S1: brake disc casting and pattern design, wherein the pattern forms the cavity portion of the brake disc casting; S2: Riser design; S3: Riser diameter design; S4: gating system design; S5: Use the expression to create other brake discs; the other brake discs refer to brake discs with different sizes and the same structure; S6: Generate component diagram.

2. A brake disc tooling parametric design method according to claim 1, characterized in that: The specific steps of S1 include: S11: Start the UG program and create a new component file; S12: Select the Insert / Modeling command to enter the Modeling module; S13: Select the Rotate / Sketch command, use the coordinate plane XY-XZ as the sketch plane, and draw a sketch; S14: Establish an expression. First, select a brake disc product. According to the brake disc casting, model drawings and shapes, name several key dimensions of the brake disc as D1, D2, D3, D4, H1, H2, and H3, where D1, D2, D3, and D4 are the diameters of the brake disc at different positions; H1, H2, and H3 are the heights of the brake disc at different positions; enter relevant values ​​in the expression respectively; S15: Use expressions to change and indicate relevant dimensions, reduction, allowance, and draft angle on the sketch; the machining allowance is determined according to the diameter D1, and the draft angle is determined according to the height dimension; S16: Add constraints to the sketch, select the sketch outlines of the casting and model respectively, and create the casting and model with shrinkage; S17: Calculate the mass, volume and area of ​​the casting; S18: Establish product association design between components and draw casting and model drawings.

3. A brake disc tooling parametric design method according to claim 1, characterized in that: In S2, the riser is designed by the casting modulus, and the riser size is calculated by the modulus method. The calculation formula of the riser modulus is as follows: M m =1.2M z ; R=3.2M Z ; Where M Z V is the casting modulus; 铸件 is the casting volume; S 铸件 is the surface area of ​​the casting; R is the riser radius, M m is the riser modulus; The liquid metal contained in the feed riser is used to compensate for the shrinkage of the casting when cooling from the pouring temperature to the solidus and during solidification. The shrinkage rate of gray cast iron is 2%, while the utilization rate of the cylindrical feed riser is 15%. The minimum size of the feed riser is determined by the following formula: 15% × V 补缩冒口 ≥2%×V 铸件 , where V 补缩冒口 is the volume of the shrinkage feeder, V 铸件 is the casting volume; When the riser radius meets the above conditions, take the maximum value. Create a reference plane according to the riser position. The reference plane is perpendicular to the parting surface and the center line of the cross runner. On this reference plane, a riser sketch is formed by the riser width B, the riser diameter and the riser center position. Through the stretch command, draw the 3D drawings of the upper and lower parts of the riser respectively. The height of the upper riser is 1.8*R, and the draft angle is 2°. The height of the lower riser is 1.2*R, and the draft angle is 5°.

4. A brake disc tooling parametric design method according to claim 3, characterized in that: In order to increase the shrinkage compensation effect of the riser, the modulus size is 0.6 times of the casting, the riser diameter length is 0.3 times of the riser radius, and the riser diameter modulus is calculated according to the cuboid modulus. The formula is as follows: <h2 style=";text-align:left;direction:ltr">M<h2 style=";text-align:left;direction:ltr"> J <h2 style=";text-align:left;direction:ltr"> <0.6M<h2 style=";text-align:left;direction:ltr"> m <h2 style=";text-align:left;direction:ltr"> =0.6×1.2M<h2 style=";text-align:left;direction:ltr"> z <h2 style=";text-align:left;direction:ltr"> <0.72M<h2 style=";text-align:left;direction:ltr"> z <h2 style=";text-align:left;direction:ltr"> ; Therefore, the riser width b is calculated as: b=5.625M z ; Where M J is the riser diameter modulus; b is the riser diameter width; M Z M is the casting modulus; m is the riser modulus; Draw a riser sketch based on the riser width b and the riser shape, and use the stretch command to draw a 3D diagram of the riser.

5. A brake disc tooling parametric design method according to claim 1, characterized in that: The pouring system is used to introduce molten iron and fill the mold cavity with the molten iron within a specified time. The pouring system includes a straight runner, a horizontal runner and an inner runner.

6. A brake disc tooling parametric design method according to claim 5, characterized in that: In order to ensure the smooth filling of molten iron, the cross-sectional area of ​​the pouring system and the cross-sectional ratio of each component of the pouring system are as follows: F 直 :F 阻 :F 横 :F 内 =1.1:1:1.4:1.2; in: G=G z / 85% F 直 =πf 2 ; In the formula, F 直 is the straight cross-sectional area; F 阻 Cross-sectional area of ​​the runner at the flow-blocking part; F 横 is the cross-sectional area of ​​the runner; F 内 is the cross-sectional area of ​​the ingates; G is the weight of the molten iron flowing through the flow-blocking section, including the sum of the weights of the casting, runner, ingates, and risers; G z is the casting mass; H is the height of the pouring pressure head; K is the resistance area coefficient. For cast iron, K is 1036; m is the shape coefficient of the resistance pouring system. According to the shape of the resistance section, it is taken as 0.6; a is the width of the inner runner; t is the pouring time; and f is the radius of the straight runner.

Images