Automatic casting process for automobile brake disc

Abstract

The invention relates to the technical field of brake disc casting, and discloses an automatic casting process for an automobile brake disc, which comprises the following steps: inserting an aluminum core into a mold from the side surface of the mold according to a preset interval in parallel to the horizontal plane, fixing, and enabling the aluminum core to be in contact with a primary-layer carbon composite material; mapping a pressing space of a gap between adjacent aluminum cores into a pressing pattern in a manner of being vertical to a horizontal plane; executing an inner triangle segmentation strategy, and designing an inner triangle in the pressed graph to obtain a target pressed space; executing an ingredient filling calculation strategy, calculating the volume of the carbon composite material used for filling the target pressing space, and recording the volume as a target volume; putting a target volume of carbon composite into the target pressing space; executing a feedback adjustment strategy, measuring the actual pressing force of the target pressing space in real time, adjusting the size of the target volume, and adjusting the size of the target pressing space; and an inner polygon segmentation strategy is executed, an inner polygon is designed in the pressing graph, pressing of the brake disc is completed, preferential filling of the sharp corner area is achieved, and quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of brake disc casting, and specifically to an automated casting process for automotive brake discs. Background Art

[0002] Carbon fiber reinforced ceramic brake discs have the advantages of light weight, high thermal stability, strong wear resistance, and stable friction performance, and are widely used in aerospace and high-end vehicle braking systems. Their preparation process usually includes multiple hot pressing processes such as carbon fiber preforming, carbonization treatment, and silicon infiltration. Among them, the pressing quality of the carbon fiber preform in the preforming stage plays a key role in the overall mechanical properties.

[0003] The current carbon fiber brake disc forming process still has significant defects in complex structural areas. Especially in molds with sharp corners, slits, or thin-walled structures, it is difficult for carbon fiber to be fully filled and compacted. Specifically: Difficulty in pressing at sharp corners: The inner angle corresponding to the sharp corner is small, resulting in easy flow-around of the material during flow, that is, the carbon fiber tends to preferentially fill the area with a larger angle, forming a cavity or low-density area at the sharp corner. Insufficient flow driving force: The traditional constant-pressure pressing method is difficult to generate sufficient driving force in narrow areas, making it difficult for carbon fiber to enter the sharp corner, thereby affecting the local strength. Insufficient rigidity in structural design: Most existing design methods do not distinguish and process different angle areas, resulting in the pressing path being unable to accurately guide the carbon fiber to flow into the sharp corner area, causing problems such as low material utilization rate and uneven filling. Lack of real-time feedback mechanism: The existing process lacks a dynamic monitoring mechanism for the flow state of carbon fiber and the pressing force, and cannot actively compensate before problems occur, affecting the density and performance consistency of the finished product.

[0004] This solution proposes an automated casting process for automotive brake discs, constructs an auxiliary inner triangle, and combines a real-time feedback control mechanism for the flow velocity of carbon fiber and the local pressing force to achieve preferential filling and dynamic compensation in the sharp corner area, improving the overall pressing density and structural consistency. Summary of the Invention

[0005] The present invention provides an automated casting process for automotive brake discs to help solve the problems mentioned in the above background art.

[0006] The present invention provides the following technical solution: An automated casting process for automotive brake discs, including:

[0007] S1. Pour carbon fiber into the mold for casting the brake disc in two times;

[0008] After the first pouring of carbon fiber, insert the aluminum core into the mold from the side of the mold at a predetermined interval and fix it;

[0009] The mold is placed parallel to the horizontal plane;

[0010] S2. Map the pressing space of the adjacent aluminum core gaps in the mold perpendicularly to the horizontal plane into a pressing pattern;

[0011] The pressing pattern is an isosceles triangle. Set the three vertices of the pressing pattern as vertex A, vertex B, and vertex C respectively;

[0012] S3. Arrange metal sliders inside the mold. The metal sliders are used to divide the pressing space;

[0013] For the pressing pattern corresponding to any pressing space;

[0014] Execute the inner triangle division strategy, design an inner triangle in the pressing pattern, and obtain the target pressing space;

[0015] S4. Pour the carbon composite material into the mold for the second time. Specifically:

[0016] Measure the pressing thickness of the target pressing space;

[0017] Execute the batching filling calculation strategy, calculate the volume of the carbon composite material used to fill the target pressing space, and denote it as the target volume;

[0018] Put the target volume of the carbon composite material into the target pressing space;

[0019] S5. Apply a target pressing force to the target pressing space for pressing;

[0020] Execute the feedback adjustment strategy, measure the actual pressing force of the target pressing space in real time, adjust the size of the target volume, and adjust the size of the target pressing space;

[0021] S6. Execute the inner polygon division strategy, design an inner polygon in the pressing pattern, and complete the pressing of the brake disc.

[0022] Preferably, the execution of the inner triangle division strategy, designing an inner triangle in the pressing pattern, and obtaining the target pressing space includes:

[0023] In the pressing pattern, the interior angles B and C corresponding to vertex B and vertex C are equal, and the interior angle A corresponding to vertex A is the smallest;

[0024] Denote the side connecting vertex A and vertex B as the first side length, the side connecting vertex A and vertex C as the second side length, and the side connecting vertex B and vertex C as the third side length;

[0025] Measure the lengths of the first side length, the second side length, and the third side length respectively to obtain , and ;

[0026] Calculate the size of the interior angle A , ;

[0027] Select an arbitrary point E on the first side length and design a new inner triangle, where the inner triangle is composed of vertex A, vertex C, and point E;

[0028] Denote the side length between vertex A and point E as the fourth side length , and satisfy , , where is the reconstruction point ratio coefficient, which is used to determine the position of point E on the first side length;

[0029] Calculate the magnitudes of interior angles B and C, , where is the magnitude of interior angle B, is the magnitude of interior angle C;

[0030] Among them, the calculation formula for the reconstruction point ratio coefficient is .

[0031] Preferably, when implementing the inner triangle segmentation strategy, design an inner triangle in the pressing pattern to obtain the target pressing space, including:

[0032] Establish a two-dimensional coordinate system with vertex A as the origin;

[0033] Obtain the position of vertex C in the two-dimensional coordinate system ;

[0034] Obtain the position of point E in the two-dimensional coordinate system ;

[0035] Connect vertex C and point E to establish a dividing edge , then , is the direction vector of the dividing edge;

[0036] Use the direction vector of the dividing edge to adjust the position of the metal sliding piece. Specifically:

[0037] Initially embed the metal sliding piece on the arm body where the first side length of the pressing space is located;

[0038] Adjust the position of the metal sliding piece, and embed the metal sliding piece in the pressing space parallel to the direction vector of the dividing edge. The metal sliding piece serves as a dividing surface, and the dividing surface is perpendicular to the horizontal plane to divide the pressing space into two parts;

[0039] Denote the pressing space where the inner triangle is located as the target pressing space.

[0040] Preferably, when implementing the batching filling calculation strategy, calculate the volume of the carbon composite material used to fill the target pressing space, including:

[0041] Obtain the length of the dividing edge ;

[0042] Draw a height perpendicular to the dividing edge through vertex A and measure the length of the height ;

[0043] Obtain the pressing thickness ;

[0044] Calculate the volume of the target pressing space , ;

[0045] Set the pressing correction coefficient , which is used to quantify the volume shrinkage of the carbon composite material during pressing;

[0046] The said pressing correction coefficient is obtained through experiments, and the calculation method is:

[0047] Measure the initial volume of the carbon composite material used for the experiment ;

[0048] Press the carbon composite material and measure the volume after pressing ;

[0049] Calculate the pressing correction coefficient ;

[0050] Calculate the target volume of the carbon composite material used to fill the target pressing space , , where is the set waste volume correction coefficient, which is used to represent the loss of the carbon composite material during pressing.

[0051] Preferably, when implementing the feedback adjustment strategy, the actual pressing force of the target pressing space is measured in real time, the size of the target volume is adjusted, and the size of the target pressing space is adjusted, including:

[0052] Adjust the size of the target volume, specifically:

[0053] During the pressing of the target pressing space, measure the flow velocity of the carbon composite material in real time ;

[0054] Set the minimum flow velocity of the carbon composite material ;

[0055] Compare the size relationship between the flow velocity of the carbon composite material at time t and the minimum flow velocity;

[0056] If , it is determined that the carbon composite material in the target pressing space is insufficient;

[0057] The additional volume of the carbon composite material to be put in is , , where is the speed feedback gain coefficient;

[0058] Draw a circle on the inner triangle with vertex A as the center and length u as the radius. Denote the area where the circle intersects the inner triangle as the target area, and u is less than the length of the fourth side;

[0059] Measure the actual pressing force received within the target area ;

[0060] Compare the magnitudes of the actual pressing force and the target pressing force . If the actual pressing force is less than the target pressing force, the additional volume of carbon composite material to be added is , , where is the pressing force feedback gain coefficient;

[0061] Calculate the final additional volume of carbon composite material , , is the regulation weight factor, used to represent the importance of the flow velocity;

[0062] Among them, the calculation formula for the regulation weight factor is: , is the change rate of the flow velocity, is the change rate of the actual pressing force, is the absolute value of the change rate of the flow velocity, is the absolute value of the change rate of the actual pressing force;

[0063] Among them, when the absolute value of the change rate of the flow velocity is greater than or equal to the absolute value of the change rate of the actual pressing force, the regulation weight factor increases;

[0064] When the absolute value of the change rate of the flow velocity is less than the absolute value of the change rate of the actual pressing force, the regulation weight factor decreases.

[0065] Preferably, when implementing the feedback regulation strategy, the actual pressing force in the target pressing space is measured in real time, the size of the target volume is adjusted, and the size of the target pressing space is adjusted, including:

[0066] Adjust the size of the target pressing space, specifically:

[0067] When the actual pressing force is less than the target pressing force, it is determined that the carbon composite material in the target area is insufficient, and the reconstruction point proportion coefficient is reduced to increase the flow of carbon composite material towards corner A;

[0068] Among them, the reduced reconstruction point proportion coefficient is , , where is the sensitivity coefficient.

[0069] Preferably, the implementation of the inner polygon segmentation strategy involves designing an inner polygon in the pressing pattern to complete the pressing of the brake disc, including:

[0070] Obtain the intersection points of the target area with the first side length and the second side length, and denote them as point X and point Y respectively;

[0071] Obtain the positions of point X and point Y in the two-dimensional coordinate system, and denote them as and ;

[0072] Denote the side connecting point X and point Y as the sixth side length, calculate the direction vector of the sixth side length, adjust the position of the metal sliding piece, and embed the metal sliding piece along the direction vector into the pressing space to form a new dividing surface, and the new dividing surface divides the pressing space into two parts;

[0073] Form an inner polygon XYBC in the pressing pattern, and use the pressing space corresponding to the inner polygon XYBC as the new target pressing space;

[0074] Pour carbon composite material into the new target pressing space for pressing.

[0075] Preferably, the pouring of carbon composite material into the new target pressing space for pressing includes:

[0076] The inner polygon XYBC is an isosceles trapezoid, the sixth side length is parallel to the third side length, and measure the distance r from the sixth side length to the third side length;

[0077] Calculate the volume of the new target pressing space as , where is the length of the sixth side length;

[0078] Calculate the volume of the carbon composite material used to press the new target pressing space ;

[0079] Pour volume of carbon composite material into the new target pressing space, and use the target pressing force to press the new target pressing space;

[0080] Measure the actual pressing force of the new target pressing space in real time, and add additional carbon composite material to control the actual pressing force to be equal to the target pressing force.

[0081] The present invention has the following beneficial effects:

[0082] 1. In the automated casting process of the automotive brake disc, due to the small included angle in the pressed pattern, the inner angle A forms a sharp corner area, and there are significant filling difficulties during the pressing process. The reasons are as follows: The carbon composite material has certain directionality and viscosity when flowing. When encountering a sharp spatial contraction area like the inner angle A, the material is difficult to expand along the corner, and voids or pressing dead corners are likely to occur, resulting in insufficient pressing density in this area. By introducing a reconstruction point ratio coefficient to design a new inner triangle to change the property that the inner angle A is the smallest inner angle, at this time, the inner angle A can be used as the preferred flow path for priority filling. The guided geometric reconstruction can improve the filling density of the sharp corner area and the overall pressing uniformity, effectively avoiding the forming defects caused by geometric sharp corners.

[0083] 2. In the automated casting process of the automotive brake disc, by establishing a two-dimensional coordinate system with vertex A and combining the spatial positions of point E and point C, a dividing edge is constructed and its direction vector is used to guide the adjustment of the position of the metal slide, so that the slide forms a diversion structure facing the target area, which can effectively change the filling direction of the carbon composite material and make it preferentially flow into the designed target pressing space. Using the direction of the dividing edge as a control variable, the standardization and automated control of the guiding structure are realized, simplifying manual intervention, improving the process repeatability and accuracy, and enhancing the directional filling ability of the carbon composite material in the asymmetric complex structure.

[0084] 3. In the automated casting process of the automotive brake disc, through precise geometric calculations, the length, height, and pressing thickness of the dividing edge are determined, so as to accurately obtain the actual volume of the target pressing space. On this basis, a compression correction coefficient ε and a waste correction coefficient γ are introduced to ensure that the volume of the carbon composite material fed takes into account the shrinkage and loss of the material during the pressing process while meeting the requirements of the shape forming, avoiding problems such as excessive feeding or insufficient pressing density. It saves costs while ensuring the consistency and density of the products.

[0085] 4. In the automated casting process of the automotive brake disc, through a real-time feedback mechanism, the flow rate and local pressing force of the carbon composite material are dynamically monitored during the pressing process. When the parameters are lower than the preset thresholds, the additional carbon composite material volume is calculated and added respectively according to the paths of insufficient flow rate or insufficient pressing force. Through the dual compensation mechanism, the sufficient filling of the material in the sharp corner area is ensured. Combining with the regulation weight factor, the influence weights of flow and pressure in the actual pressing can be dynamically balanced, improving the adaptive ability and regulation accuracy of the control system. By dynamically adjusting the reconstruction point ratio coefficient to optimize the size of the target pressing space, increasing the angle ratio of the inner angle A in the inner triangle, enhancing the flow of the carbon composite material towards the inner angle A, it has good self-learning and closed-loop optimization capabilities.

[0086] 5. The automated casting process for the automotive brake disc obtains the intersection points of the target area with the first and second side lengths, combines their direction vectors, further promotes the adjustment of the metal sliding piece, and realizes the construction of the secondary segmentation pressing area. The newly formed XYBC area serves as the inner polygon and has relatively regular trapezoidal geometric features. Since the angles of interior angle B and interior angle C are relatively large, no sharp corner area will be formed, and the filling is relatively simple. To improve the filling and pressing efficiency, the XYBC area is directly filled during secondary filling, realizing the layer-by-layer construction of complex structures and ensuring the continuity, uniformity, and pressing integrity of the overall structure.

[0087] 6. The automated casting process for the automotive brake disc accurately measures the height r of the trapezoid and the sixth side length, precisely calculates the volume of the new pressing space, and corrects the carbon composite material feeding volume in combination with the foregoing method. The pressing process is completed with the same target pressing force, supplemented by a real-time force feedback mechanism to dynamically adjust the additional amount of carbon composite material and ensure consistent pressing density. BRIEF DESCRIPTION OF THE DRAWINGS

[0088] Figure 1 It is a schematic flow chart of the method of the present invention.

[0089] Figure 2 It is a schematic diagram of the mold structure of the present invention.

[0090] Figure 3 It is a schematic diagram of the inner triangle structure of the present invention.

[0091] Figure 4 It is a schematic diagram of the inner polygon structure of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0092] 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 only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0093] Example 1. Refer to Figure 1 , an automated casting process for an automotive brake disc, including:

[0094] The brake disc is a high-performance composite brake component made of carbon composite material reinforced material, with advantages such as high strength, high temperature resistance, light weight, and good thermal stability, and is widely used in high-end automobiles, aerospace, and rail transit and other fields.

[0095] Carbon composite refers to a carbon / carbon composite material formed by using carbon composite as the reinforcing material and carbonizable materials such as resin, tar, and coal pitch as the matrix, through processes such as molding, carbonization, and carbon addition. It has excellent high-temperature resistance, mechanical strength, and thermal stability, and is widely used in high-performance brake systems.

[0096] Its production process generally includes the following main steps:

[0097] Raw material preparation: Select chopped carbon composite, resin, or tar-based carbon precursor as the main raw materials;

[0098] Preform pressing: Fill the carbon composite mixture into the mold for pressing to initially form the blank structure of the brake disc;

[0099] Carbonization treatment: Heat the preform at high temperature in an inert atmosphere to convert the organic components into a carbonaceous skeleton;

[0100] Carbon addition process: Further improve the material density by means of chemical vapor deposition or polymer impregnation pyrolysis;

[0101] Final processing: Include machining, surface treatment, quality inspection, etc. to obtain the finished brake disc.

[0102] During the compression molding process of carbon composite, since it is composed of chopped carbon composite and carbonizable matrix, the overall fluidity of the material is poor, the friction between particles is large, and it is difficult to flow smoothly into sharp corners or complex geometric regions. It is easy to form "filling dead corners", resulting in material accumulation and orientation disorder, and then defects such as insufficient density, pores, or cracks, seriously affecting the consistency and mechanical properties of the product.

[0103] Regarding preform pressing: Fill the carbon composite mixture into the mold for pressing to initially form the blank structure of the brake disc. Specifically:

[0104] S1. Pour carbon composite into the mold for casting the brake disc to obtain the initial layer of carbon composite;

[0105] Insert the aluminum core parallel to the horizontal plane into the mold from the side of the mold at a predetermined spacing and fix it. The aluminum core contacts the initial layer of carbon composite;

[0106] In this embodiment, the set aluminum core is a removable sacrificial structural member. During the compression molding process of carbon composite, by using its high thermal conductivity, it effectively improves the heat conduction rate in the mold cavity, realizes thermal field equilibrium, and reduces defects caused by thermal non-uniformity;

[0107] After pressing and preliminary heat treatment are completed, the aluminum core is removed by melting, chemical dissolution, or mechanical means to form a preset void channel structure; this void structure is permanently retained inside the brake disc for:

[0108] Enhancing the heat dissipation efficiency during the service process of the brake disc;

[0109] Accelerate the outward diffusion of frictional heat and reduce the risk of heat accumulation;

[0110] Prevent problems such as heat fade and heat cracking caused by too rapid temperature rise;

[0111] Improve the stability and durability of the braking system under high-intensity working conditions.

[0112] S2. Map the pressing space between adjacent aluminum cores perpendicular to the horizontal plane into a pressing pattern;

[0113] In this embodiment, referring to Figure 2 , the fan-shaped structure between adjacent aluminum cores can be simulated as an isosceles triangle;

[0114] The pressing pattern is an isosceles triangle. Set the three vertices of the pressing pattern as vertex A, vertex B, and vertex C respectively. The interior angles B and C corresponding to vertex B and vertex C are equal, and the interior angle A corresponding to vertex A is the smallest;

[0115] S3. Arrange metal sliders inside the mold, and the metal sliders are used to divide the pressing space;

[0116] For the pressing pattern corresponding to any one pressing space;

[0117] Execute the inner triangle division strategy, design an inner triangle in the pressing pattern to obtain the target pressing space;

[0118] S4. Measure the pressing thickness of the target pressing space;

[0119] Execute the batching filling calculation strategy, calculate the volume of the carbon composite material used to fill the target pressing space, and record it as the target volume;

[0120] Put the target volume of the carbon composite material into the target pressing space;

[0121] S5. Apply a target pressing force to the target pressing space for pressing;

[0122] Execute the feedback adjustment strategy, measure the actual pressing force of the target pressing space in real time, adjust the size of the target volume, and adjust the size of the target pressing space;

[0123] S6. Execute the inner polygon division strategy, design an inner polygon in the pressing pattern to complete the pressing of the brake disc.

[0124] The step of executing the inner triangle division strategy, designing an inner triangle in the pressing pattern to obtain the target pressing space includes:

[0125] In the pressing figure, the side connecting vertex A and vertex B is denoted as the first side length, the side connecting vertex A and vertex C is denoted as the second side length, and the side connecting vertex B and vertex C is denoted as the third side length;

[0126] Measure the lengths of the first side length, the second side length, and the third side length respectively to obtain , and ;

[0127] Calculate the size of interior angle A , ;

[0128] Arbitrarily select a point E on the first side length to design a new inner triangle, which is composed of vertex A, vertex C, and point E;

[0129] Denote the side length between vertex A and point E as the fourth side length , and satisfy , , where is the reconstruction point ratio coefficient, which is used to determine the position of point E on the first side length;

[0130] Calculate the sizes of interior angle B and interior angle C, ;

[0131] Among them, the calculation formula of the reconstruction point ratio coefficient is .

[0132] By numbering each side in the original pressing figure and introducing the reconstruction point ratio coefficient, and selecting point E between vertex A and vertex B to construct the auxiliary triangle AEC, the reconstruction of the sharp corner area can be realized geometrically. Especially at interior angle A, this area usually has a small included angle, which is likely to cause insufficient carbon composite material accumulation or flow blockage, resulting in insufficient local strength after forming. After designing the inner triangle, the position of point E can be artificially adjusted. By changing the shape of AEC, the carbon composite material can be guided to preferentially fill the areas that are difficult to fill originally, effectively solving the problems of low filling rate and poor compactness at the sharp corner parts, and improving the overall structural integrity.

[0133] The implementation of the inner triangle segmentation strategy to design an inner triangle in the pressing figure to obtain the target pressing space includes:

[0134] Establish a two-dimensional coordinate system with vertex A as the coordinate origin;

[0135] Obtain the position of vertex C in the two-dimensional coordinate system ;

[0136] Obtain the position of point E in the two-dimensional coordinate system ;

[0137] Connect vertex C and point E to establish the dividing edge , then , is the direction vector of the dividing edge;

[0138] Use the direction vector of the dividing edge to adjust the position of the metal slide. Specifically:

[0139] Initially embed the metal slide in the arm body where the first side length is located in the pressing space;

[0140] Adjust the position of the metal slide and embed the metal slide in the pressing space along the direction vector of the dividing edge to form a dividing surface;

[0141] Record the pressing space where the inner triangle is located as the target pressing space.

[0142] In this embodiment, referring to Figure 3 , in the inner triangle, the angle of interior angle A forms a pointed corner area to improve the flow of the carbon composite material towards interior angle A.

[0143] After obtaining the vertex coordinates and calculating the direction vector of the dividing edge using a two-dimensional coordinate system, the metal slide can be embedded in the mold along this direction to achieve dynamic division and guidance of the carbon composite material pressing space. This method has good structural adaptability and process implementability, can cooperate with the configuration of the inner triangle, form a clear physical separation in the mold, and thus more accurately control the flow direction of the carbon composite material between different regions. The adjustable embedding method of the slide is also convenient for multi-round reconstruction and region switching, improving the consistency of multi-region pressing.

[0144] The execution of the batching filling calculation strategy to calculate the volume of the carbon composite material used to fill the target pressing space includes:

[0145] Obtain the length of the dividing edge ;

[0146] Draw a height perpendicular to the dividing edge from vertex A and measure the length of the height ;

[0147] Obtain the pressing thickness ;

[0148] Calculate the volume of the target pressing space , ;

[0149] Set the pressing correction coefficient , used to quantify the volume shrinkage of the carbon composite material during pressing;

[0150] The pressing correction coefficient is obtained through experiments, and the calculation method is:

[0151] Measure the initial volume of the carbon composite material used for the experiment ;

[0152] Press the carbon composite and measure the volume after pressing ;

[0153] Calculate the suppression correction factor ;

[0154] Calculate the target volume of carbon composite material to fill the target pressing space , ,in, It is the set waste volume correction factor, which is used to represent the loss of carbon composite materials during the pressing process.

[0155] By calculating the base, corresponding height, pressing thickness and other geometric quantities of the triangle AEC, combined with the compression correction coefficient ε and the waste correction coefficient δ, the system can accurately obtain the actual feeding volume of the carbon composite. This avoids the errors caused by traditional empirical estimation and ensures that the initial feeding volume of the carbon composite strictly matches the actual pressing space. With the parameterization of the model, dynamic batching adjustment can be achieved, the intelligence of the feeding system can be improved, the material distribution in the initial stage of pressing can be ensured to be uniform, and the occurrence of material waste and pressing defects can be effectively controlled.

[0156] The execution feedback adjustment strategy measures the actual pressing force of the target pressing space in real time, adjusts the size of the target volume, and adjusts the size of the target pressing space, including:

[0157] Adjust the size of the target volume, specifically:

[0158] Real-time measurement of the flow velocity of carbon composites during the pressing process of the target pressing space ;

[0159] Setting the minimum flow rate of carbon composites ;

[0160] Compare the flow velocity of the carbon composite material at time t and the minimum flow velocity. , it is determined that the carbon composite material in the space where the inner angle A is located is insufficient;

[0161] In this embodiment, the low flow velocity indicates that the material moves slowly in the flow path, and the material may not be able to flow into place at sharp corners or local areas. The physical reasons may include insufficient material such as insufficient volume, high viscosity, poor temperature, and large path resistance, such as narrow sharp corners.

[0162] The volume of additional carbon composite material is , ,in, is the speed feedback gain coefficient;

[0163] Draw a circle with vertex A as the center and length u as the radius. Denote the area where the circle intersects with the inner triangle as the target area, where u is less than the length of the fourth side;

[0164] Measure the actual pressing force received within the target area ;

[0165] Compare the magnitudes of the actual pressing force and the target pressing force If the actual pressing force is less than the target pressing force, the additional volume of carbon composite material to be added is , , where is the pressing force feedback gain coefficient;

[0166] In this embodiment, the pressing force reflects the density. If the carbon composite material is reasonably distributed and dense, the reaction force received by the mold wall during pressing should reach the target value. A low pressure indicates that the material is insufficient, there is insufficient material filling, many voids, and insufficient material stiffness, and the mold cavity corners are not filled.

[0167] Calculate the final additional volume of carbon composite material , is the regulation weight factor, which is used to represent the importance degree of the flow velocity;

[0168] Among them, the calculation formula of the regulation weight factor is: .

[0169] Among them, when the absolute value of the flow velocity change rate is greater than or equal to the absolute value of the actual pressing force change rate, the regulation weight factor increases;

[0170] When the absolute value of the flow velocity change rate is less than the absolute value of the actual pressing force change rate, the regulation weight factor decreases;

[0171] Although constructing an auxiliary inner triangle can geometrically optimize the pressing path and guide the carbon composite material to preferentially flow into the sharp corner area, improving the filling effect from the source, geometric design essentially belongs to structural prior regulation, and its effect lies in optimizing the initial flow trend of the material and the pressing area division. However, in the actual manufacturing process, limited by material properties, environmental disturbances, mold assembly errors, and the anisotropy of the carbon composite material itself, the structural design may still not be able to completely solve all the filling non-uniformity problems at the micro level; the introduction of a real-time feedback mechanism, especially the dynamic monitoring of the flow velocity v(t) and local pressing force P(t) of the carbon composite material, is a means of posterior compensation for the behavior of the geometric scheme. By setting thresholds to judge and trigger the compensation mechanism, it is possible to respond in advance before insufficient filling or insufficient pressing of the carbon composite material occurs and actively correct the distribution of the carbon composite material;

[0172] The advantage of the combination of the two is that:

[0173] Geometric assisted design provides a priori filling guidance to optimize the material diversion path under the theoretical model;

[0174] Real-time dynamic feedback compensates for actual deviations and maintains pressing uniformity through a refined compensation mechanism;

[0175] The two work together to form a structure-feedback two-way closed-loop control mechanism, showing stronger adaptive capabilities in sharp-corner areas, narrow areas, or regions with thickness changes;

[0176] By using the regulation weight factor, the control strategy dominated by fluidity or pressure can be dynamically adjusted according to different stages, significantly improving the accuracy, stability, and consistency in complex pressing tasks.

[0177] Although geometric design does not solve all problems, its value lies in optimizing at the source. Adjusting the prior structure can greatly reduce the possibility of errors and relieve the subsequent regulation pressure.

[0178] In this embodiment, in the molding production of a certain type of brake pad, there is an obvious sharp-corner structure in the product contour, and the minimum angle is about 35°. In the initial scheme without auxiliary structure design, defects such as incomplete filling of carbon composite materials often occur in the sharp-corner area, and the specific manifestations are as follows:

[0179] 1) There are obvious delaminations or pores on the surface of the finished product;

[0180] 2) X-ray CT scanning shows that the density in this area is low, affecting the overall shear strength and service life.

[0181] By introducing an auxiliary inner triangle design, that is, introducing a point E between the two sides AB and AC of the sharp corner, reconstructing triangle AEC, making the original sharp angle A become part of the inner triangle, and transforming it into an area that is easier to fill. This structural design changes the initial flow path of the carbon composite material in the mold, enabling the material to preferentially fill the sharp-corner area that was originally difficult to cover.

[0182] Result comparison:

[0183] Before using this geometric assistance scheme, the product rejection rate was as high as 15%. After introducing the structural design, even without introducing real-time feedback compensation, the rejection rate dropped below 5%. Combining with the dynamic monitoring feedback compensation mechanism, the product consistency was greatly improved, and the forming defects were almost eliminated.

[0184] In summary, this "structure preset + behavior feedback" composite regulation framework takes into account both global optimization and local adaptability when pressing precision carbon composite structural parts, effectively ensuring the forming quality and batch stability of the products.

[0185] The flow velocity v(t) and local pressing force P(t) of the carbon composite material are monitored in real time, and thresholds are set for judgment. Once the detected value is lower than the preset value, the additional feeding operation is realized by the gain coefficient and automatically calculating the compensation volume. Such a dual feedback mechanism can dynamically adapt to the microscopic behavior differences of the material in the mold and overcome the local deficiency problem caused by single feeding. By introducing a regulation weight factor α for balance adjustment, the control strategy of prioritizing fluidity or pressure can be dynamically optimized, improving the robustness of the pressing process and the consistency of the finished product.

[0186] When implementing the feedback regulation strategy, the actual pressing force of the target pressing space is measured in real time, the size of the target volume is adjusted, and the size of the target pressing space is adjusted, including:

[0187] Adjusting the size of the target pressing space specifically includes:

[0188] When the actual pressing force is less than the target pressing force, it is determined that the inner angle A is insufficiently pressed, and the reconstruction point proportion coefficient is reduced to increase the flow of the carbon composite material towards the inner angle A;

[0189] , where is the reduced reconstruction point proportion coefficient, is the sensitivity coefficient.

[0190] When it is recognized that the pressing force in the sharp corner area is insufficient, by lowering the reconstruction point proportion coefficient λ, the point E is shifted towards the direction close to the vertex A, thereby reconstructing a sharper auxiliary triangle AEC. This operation directly increases the flow path and probability of the carbon composite material towards the inner angle A, strengthening the key filling control of this area. With the adjustment of the sensitivity coefficient, the morphology of the reconstructed triangle can be finely controlled, forming an intelligent response adjustment mechanism to ensure that the sharp corner area can be fully compacted under various working conditions, effectively improving the local density.

[0191] When implementing the inner polygon segmentation strategy, an inner polygon is designed in the pressing pattern to complete the pressing of the brake disc, including:

[0192] Obtain the intersection points of the target area with the first side length and the second side length, and denote them as point X and point Y respectively;

[0193] Obtain the positions of point X and point Y in the two-dimensional coordinate system, and denote them as and respectively;

[0194] Denote the side connecting point X and point Y as the sixth side length, calculate the direction vector of the sixth side length, adjust the position of the metal slide, and embed the metal slide into the pressing space along the direction vector to form a new dividing surface;

[0195] Construct an inner polygon XYBC in the pressing pattern, and use the pressing space corresponding to the inner polygon XYBC as the new target pressing space;

[0196] Pour carbon composite material into the new target pressing space for pressing.

[0197] In this embodiment, referring to Figure 4 , the four interior angles in the inner polygon do not form a sharp corner area. Therefore, the flow of the carbon composite material can easily fill each interior angle completely. At this time, the triangle AXY has been filled and pressed. Filling the inner polygon at one time can improve the filling efficiency.

[0198] By obtaining the intersection points of the auxiliary circle and the triangle to construct point X and point Y, and further forming the inner polygon XYBC in the pattern, the system can implement a multi-stage filling strategy according to the current pressing progress. It is not only convenient for batch pressing by area, but also can quickly promote the pressing of subsequent areas after the first pressing is completed, reducing the overall pressing time and improving the space utilization rate. The adjustment of the direction vector-assisted sliding piece can also achieve continuous sliding piece reconstruction and improve the adaptability of the mold.

[0199] The step of pouring carbon composite material into the new target pressing space for pressing includes:

[0200] The inner polygon XYBC is an isosceles trapezoid, the sixth side is parallel to the third side, and the distance r between the sixth side and the third side is measured;

[0201] Calculate the volume of the new target pressing space as , where is the length of the sixth side;

[0202] Calculate the volume of the carbon composite material used to press the new target pressing space ;

[0203] Pour volume of carbon composite material into the new target pressing space, and use the target pressing force to press the new target pressing space;

[0204] Measure the actual pressing force of the new target pressing space in real time, and add additional carbon composite material to control the actual pressing force to be equal to the target pressing force.

[0205] Using the isosceles trapezoid XYBC as the target pressing space, the pressing volume and its height r can be accurately calculated through geometric derivation, and the corresponding pressing parameters can be set according to the target pressing force. The actual pressing force in this area is detected in real time, and the control logic of dynamically adding materials is executed according to the difference to ensure that the pressing force of the material in this area is always maintained within the set range. The isosceles structure has better symmetry in mechanics, which is convenient for the carbon composite material to form a uniform stress distribution inside the area, improving the consistency and structural stability of the product.

[0206] It should be noted that in this text, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements not only includes those elements, but also includes other elements not expressly listed, or elements inherent to such process, method, article or device.

[0207] The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. An automated casting process for automotive brake discs, characterized in that, Including: S1. Pour the carbon composite material into the mold for casting the brake disc in two times; After the first pouring of the carbon composite material, insert the aluminum core into the mold from the side of the mold at a predetermined interval and fix it; The mold is placed parallel to the horizontal plane; S2. Map the pressing space between adjacent aluminum cores in the mold vertically to the horizontal plane as a pressing pattern; The pressing pattern is an isosceles triangle, and the three vertices of the pressing pattern are set as vertex A, vertex B, and vertex C respectively; S3. Arrange metal sliding plates inside the mold, and the metal sliding plates are used to divide the pressing space; For any pressing pattern corresponding to a pressing space; Execute the inner triangle division strategy, design an inner triangle in the pressing pattern to obtain the target pressing space; S4. Pour the carbon composite material into the mold for the second time, specifically: Measure the pressing thickness of the target pressing space; Execute the batching filling calculation strategy, calculate the volume of the carbon composite material used to fill the target pressing space, denoted as the target volume; Put the target volume of the carbon composite material into the target pressing space; S5. Apply a target pressing force to the target pressing space for pressing; Execute the feedback adjustment strategy, measure the actual pressing force of the target pressing space in real time, adjust the size of the target volume, and adjust the size of the target pressing space; S6. Execute the inner polygon division strategy, design an inner polygon in the pressing pattern to complete the pressing of the brake disc.

2. The automated casting process for automotive brake discs according to claim 1, characterized in that, The execution of the inner triangle division strategy, designing an inner triangle in the pressing pattern to obtain the target pressing space includes: In the pressing pattern, the interior angles B and C corresponding to vertex B and vertex C are equal, and the interior angle A corresponding to vertex A is the smallest; Denote the side connecting vertex A and vertex B as the first side length, the side connecting vertex A and vertex C as the second side length, and the side connecting vertex B and vertex C as the third side length; The lengths of the first side length, the second side length, and the third side length are measured respectively to obtain , and ; Calculate the size of interior angle A , ; Select any point E on the first side length and design a new inner triangle, and the inner triangle is composed of vertex A, vertex C, and point E; Denote the side length between vertex A and point E as the fourth side length , and it satisfies , , where is the reconstruction point proportionality coefficient, which is used to determine the position of point E on the first side length; Calculate the magnitudes of interior angles B and C, , where, is the magnitude of interior angle B, is the magnitude of interior angle C; Among them, the calculation formula for the reconstruction point ratio coefficient is: .

3. The automated casting process for automotive brake discs according to claim 2, characterized in that, The execution of the inner triangle division strategy, designing an inner triangle in the pressing pattern to obtain the target pressing space includes: Establish a two-dimensional coordinate system with vertex A as the coordinate origin; Obtain the position of vertex C in the two-dimensional coordinate system ; Obtain the position of point E in the two-dimensional coordinate system ; Connect vertex C and point E to establish the dividing edge , then , is the direction vector of the dividing edge; Use the direction vector of the dividing edge to adjust the position of the metal sliding plate, specifically: Initially embed the metal sliding plate on the arm body where the first side length is located in the pressing space; Adjust the position of the metal sliding plate, embed the metal sliding plate in the pressing space parallel to the direction vector of the dividing edge, and the metal sliding plate serves as a dividing surface, and the dividing surface is perpendicular to the horizontal plane to divide the pressing space into two parts; Denote the pressing space where the inner triangle is located as the target pressing space.

4. The automated casting process of an automotive brake disc according to claim 3, characterized in that, The execution of the batching filling calculation strategy, calculating the volume of the carbon composite material used to fill the target pressing space includes: Obtain the length of the dividing edge ; Draw a height perpendicular to the dividing side through vertex A and measure the length of the height ; Obtain the pressing thickness ; Calculate the volume of the target suppression space , ; Set the pressing correction factor , which is used to quantify the volume shrinkage of carbon composites during pressing; The pressing correction coefficient Obtained from experiments, the calculation method is as follows: Measure the initial volume of the carbon composite used in the experiment ; Press the carbon composite material and measure the volume after pressing ; Calculate the pressing correction coefficient ; Calculate the target volume of carbon composite material for filling the target suppression space , , where is the set waste volume correction coefficient, which is used to represent the loss of carbon composite material during the pressing process.

5. The automated casting process for automotive brake discs according to claim 2, characterized in that, The execution of the feedback adjustment strategy, measuring the actual pressing force of the target pressing space in real time, adjusting the size of the target volume, and adjusting the size of the target pressing space includes: Adjusting the size of the target volume, specifically: During the process of suppressing the target suppression space, the flow velocity of the carbon composite material is measured in real time ; Set the minimum flow velocity of the carbon composite ; Compare the magnitude relationship between the flow velocity of the carbon composite material at time t and the minimum flow velocity; If , it is determined that the carbon composite material in the target suppression space is insufficient; The volume of the additional carbon composite material is , , where is the speed feedback gain coefficient; Draw a circle on the inner triangle with vertex A as the center and a length u as the radius, and denote the area where the circle intersects the inner triangle as the target area, and u is less than the length of the fourth side; Measure the actual pressing force received within the target area ; Compare the actual pressing force with the target pressing force in terms of magnitude. If the actual pressing force is less than the target pressing force, the additional volume of carbon composite material to be fed is , , where is the pressing force feedback gain coefficient; Calculate the volume of the finally added carbon composite , , is a regulation weight factor used to represent the importance of the flow velocity; Among them, the calculation formula of the regulation weight factor is: , is the change rate of the flow velocity, is the change rate of the actual pressing force, is the absolute value of the change rate of the flow velocity, is the absolute value of the change rate of the actual pressing force; Wherein, when the absolute value of the flow velocity change rate is greater than or equal to the absolute value of the actual pressing force change rate, the regulation weight factor increases; When the absolute value of the flow velocity change rate is less than the absolute value of the actual pressing force change rate, the regulation weight factor decreases.

6. The automated casting process for automotive brake discs according to claim 5, characterized in that, Implementing the feedback regulation strategy, the actual pressing force of the target pressing space is measured in real time, the size of the target volume is adjusted, and the size of the target pressing space is adjusted, including: Adjusting the size of the target pressing space specifically includes: When the actual pressing force is less than the target pressing force, it is determined that the carbon composite material in the target area is insufficient, and the reconstruction point proportion coefficient is reduced to increase the flow of the carbon composite material towards the inner corner A; Among them, the reduced reconstruction point proportionality coefficient is , , where is the sensitivity coefficient.

7. The automated casting process for automotive brake discs according to claim 6, characterized in that, Implementing the inner polygon segmentation strategy, an inner polygon is designed in the pressing pattern to complete the pressing of the brake disc, including: Obtaining the intersection points of the target area with the first side length and the second side length, denoted as point X and point Y respectively; Obtain the positions of point X and point Y in a two-dimensional coordinate system, denoted as and ; Denote the edge connecting point X and point Y as the sixth side length, and calculate the direction vector of the sixth side length , adjust the position of the metal sliding piece, and embed the metal sliding piece into the pressing space along the direction vector to form a new dividing surface, which divides the pressing space into two parts; Forming an inner polygon XYBC in the pressing pattern, and taking the pressing space corresponding to the inner polygon XYBC as the new target pressing space; Pouring carbon composite material into the new target pressing space for pressing.

8. The automated casting process of an automotive brake disc according to claim 7, characterized in that, Pouring carbon composite material into the new target pressing space for pressing includes: The inner polygon XYBC is an isosceles trapezoid, the sixth side length is parallel to the third side length, and the distance r from the sixth side length to the third side length is measured; Calculate the volume of the new target suppression space as , where is the length of the sixth side length; Calculate the volume of carbon composite material for pressing a new target pressing space ; Dump into the new target suppression space Carbon composite material with a certain volume, and use the target suppression force to suppress the new target suppression space; Measuring the actual pressing force of the new target pressing space in real time, and adding carbon composite material to be put in to control the actual pressing force to be equal to the target pressing force.

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