High-precision spherical hinge spherical surface grinding process

Abstract

The present application relates to a kind of high-precision ball hinge spherical grinding processes, including multi-axis linkage grinding equipment and grinding tool preparation, parameter setting, start multi-axis linkage grinding equipment and grind base and ball gland, quality detection.The grinding tool of the present application selects hard alloy material, reduces the cost of grinding tool, ensures the stability and rigidity in the grinding process;Grinding part is the spherical surface that matches with hemispherical spherical surface, ensure that it can contact spherical surface when grinding, realize uniform grinding;Diamond particles are embedded in grinding part, improve grinding effect and surface quality;Chip groove and cooling channel design, eliminate the heat and debris generated in the grinding process, evenly arc-shaped chip groove on the spherical surface of grinding tool, avoid debris accumulation in grinding area.Grinding fluid is transported to grinding area through the chip groove, reduce the area temperature, reduce the wear of grinding tool, prolong the service life of grinding tool, improve grinding efficiency and precision.

Description

Technical Field

[0001] This invention relates to the field of spherical surface processing technology in mechanical manufacturing, specifically to a high-precision spherical hinge spherical grinding process. Background Technology

[0002] In the field of mechanical manufacturing, ball joints are widely used in equipment with extremely high requirements for motion precision and reliability, such as those used in aviation, aerospace, marine, precision instruments, and robotics. As a spherical motion mechanism, a ball joint consists of three parts: a ball seat, a ball journal, and a ball cap. The spherical precision of the ball joint directly affects its motion performance and the overall stability of the equipment. Traditional ball joint spherical grinding processes have many shortcomings and cannot meet the ever-increasing high-precision demands of modern industry.

[0003] On the one hand, traditional grinding tools have a limited structure and motion, making it impossible to achieve comprehensive and uniform grinding of the spherical surface of ball joints. This results in the inability to achieve ideal precision indicators such as roundness and surface roughness. For example, in the aerospace field, insufficient spherical surface precision of ball joints can lead to motion failures in critical aircraft components, jeopardizing flight safety. On the other hand, existing grinding processes lack effective process monitoring and precise control methods, making it difficult to guarantee the consistency of processing quality for each batch of ball joints. This leads to a high scrap rate, increased production costs, reduced production efficiency, and hinders the development of related industries.

[0004] To address the above technical problems, this invention proposes a high-precision ball hinge spherical grinding process. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a high-precision spherical hinge spherical grinding process. The grinding tool is made of cemented carbide, reducing tool cost and ensuring stability and rigidity during grinding. The grinding part is spherical, matching the hemispherical surface, ensuring full contact with the spherical surface for uniform grinding. Diamond particles are embedded in the grinding part to improve grinding effect and surface quality. Chip removal grooves and cooling channels are designed to eliminate heat and debris generated during grinding. Uniform arc-shaped chip removal grooves on the spherical surface of the grinding tool prevent debris accumulation in the grinding area. Grinding fluid is delivered to the grinding area through these grooves, reducing area temperature, minimizing tool wear, extending tool life, and improving grinding efficiency and precision. The spherical hinge, composed of a base, ball neck, and ball cap, utilizes spherical grinding technology during the grinding assembly and adjustment process. Research is conducted on a combined grinding process for the base and ball cap to achieve high-precision spherical neck grinding of the spherical hinge.

[0006] The technical problem solved by this invention is achieved through the following technical solution: A high-precision ball joint spherical grinding process involves grinding the inside of the base and ball cap with a grinding tool to form a ball neck, including the following steps: Step 1: Preparation of multi-axis linkage grinding equipment and grinding tools: Install the shank of the grinding tool on the rotating shaft of the multi-axis linkage grinding equipment, and install the cutting head inside the base and ball bearing cap. The base is installed on the multi-axis linkage grinding equipment through a ball hinge clamp. Inspect and debug the control system of the multi-axis linkage grinding equipment; calibrate and debug the sensors of the intelligent detection system of the multi-axis linkage grinding equipment. Step 2, Parameter Settings: Based on the material, size, and precision requirements of the ball joint, input the initial grinding parameters into the control system and intelligent monitoring system of the multi-axis linkage grinding equipment: linear axis movement speed 5-8 m / min, acceleration 0.5-1 m / s², grinding pressure 150-250 N, grinding time 10-20 min; set sensor thresholds: pressure upper limit 300 N, temperature upper limit 300 °C, grinding tool wear warning value 0.01 mm; set an adaptive control strategy. Step 3: Start the multi-axis linkage grinding equipment to grind the base and ball cap. The multi-axis linkage system drives the grinding tools to grind the inside of the base and ball cap according to the spiral trajectory generated by NURBS interpolation. The grinding fluid is continuously delivered to the grinding area inside the base and ball cap through the cooling channel. During the grinding process, the intelligent monitoring system collects grinding pressure, temperature, and grinding tool wear data in real time and transmits the data to the control system. When the grinding pressure exceeds the set threshold, the control system reduces the movement speed of the grinding tool. When the grinding pressure at the equatorial surface reaches 280N, the control system automatically reduces the feed rate from 0.008mm / r to 0.006mm / r and the speed from 6m / min to 5.5m / min. Step 4, Quality Inspection: After grinding, a coordinate measuring machine (CMM) with an accuracy of ≤0.001mm is used to inspect the spherical roundness and cylindricity of the ball neck formed inside the base and ball cap. An atomic force microscope (AFM) with a resolution of 0.001μm is used to inspect the surface roughness of the ball neck formed inside the base and ball cap. The inspection results are compared with the preset accuracy requirements. If the inspection results meet the preset requirements (roundness ≤0.002mm, Ra≤0.01μm), the processing is completed. If the inspection results do not meet the requirements, the control system automatically retrieves the grinding process data, analyzes the cause of the error, adjusts the process parameters, and performs a second grinding until the standard is met.

[0007] Furthermore, the grinding tool includes a shank and a cutting head; the shank and cutting head are made of WC-Co cemented carbide with a hardness of HRA89-93 and wear resistance 5-8 times higher than that of ordinary high-speed steel. TiC or / and TaC alloying elements are added to adapt to the working temperature range of 150-300℃ during the grinding process.

[0008] Furthermore, the tool holder adopts the ISO standard BT40 / BT50 interface, which can be directly adapted to multi-axis linkage grinding equipment.

[0009] Furthermore, the cutter head adopts a detachable structure. According to the spherical surface size of the inner ball joint of different specifications (Φ10-Φ100mm), the spherical cutter head with the corresponding radius of curvature is fixedly connected to the cutter shank by threads, and the repeatability of positioning accuracy is ≤0.002mm.

[0010] Furthermore, the grinding area of ​​the cutting head adopts a spherical structure that matches the hemispherical surface in a 1:1 ratio, with a sphericity error ≤0.001mm and a surface roughness controlled below Ra0.005μm. It adopts a chemical nickel-diamond composite coating process, embedding diamond particles with a particle size of 5-20μm on the grinding surface, with a coating thickness of 5-8μm and an adhesion force ≥50N / mm².

[0011] Furthermore, the spherical surface of the cutter head is uniformly arranged with 3-6 spiral arc-shaped chip removal grooves, with a groove width of 8-12mm, a groove depth of 2-3mm, and a spiral angle of 15-20°.

[0012] Furthermore, the tool holder and tool head are designed with a through-type cooling channel inside, the cooling channel outlet is connected to the chip removal groove, and the cooling channel outlet adopts a fan-shaped spray structure, with a spray coverage area of ​​≥120% of the grinding area.

[0013] Furthermore, a database of grinding tool parameters was established: for titanium alloy materials, the cutting speed was set to 8-12 m / min, the feed rate to 0.005-0.01 mm / r, and the grinding depth to 0.001-0.003 mm; for high-strength stainless steel, the cutting speed was set to 10-15 m / min, the feed rate to 0.008-0.012 mm / r, and the grinding depth to 0.002-0.004 mm.

[0014] The advantages and positive effects of this invention are: 1. The grinding tool for the high-precision ball hinge spherical grinding process of this invention requires high hardness, high wear resistance, and good toughness based on the material properties of the base and ball cap being processed. Commonly used cemented carbide materials are selected to reduce the cost of the grinding tool. The overall structural design of the grinding tool ensures stability and rigidity during the grinding process. The shank is designed as a universal standard structure for easy installation on multi-axis linkage grinding equipment, while the head is specially designed according to the shape of the spherical surface inside the base and ball cap. The grinding section is the core of the grinding tool; its shape and size directly affect the grinding effect. It is designed to be a sphere that matches the hemispherical surface, ensuring full contact with the spherical surface during grinding for uniform grinding. The surface roughness of the grinding section should be low to reduce scratches on the spherical surface. Diamond particles can be embedded in the grinding section using electroplating or sintering methods to improve the grinding effect and surface quality. The chip removal groove and cooling channel design eliminates heat and debris generated during the grinding process. A uniform arc-shaped chip removal groove is designed on the spherical surface of the grinding tool to prevent debris accumulation in the grinding area, which would affect the grinding effect. The grinding slurry can be delivered to the grinding area through the chip removal groove, promoting grinding efficiency, reducing area temperature, minimizing grinding tool wear, and extending tool life. Grinding tool parameters are optimized based on factors such as the hardness of the grinding material and the performance of the grinding equipment. Parameters such as cutting speed, feed rate, and grinding depth must be properly matched to achieve the best grinding effect. This unique grinding tool design allows for targeted machining of different areas of the ball joint surface simultaneously in a single grinding process, significantly improving grinding efficiency and precision.

[0015] 2. The high-precision ball hinge spherical grinding process of this invention, through multi-axis linkage control, achieves a spherical roundness error of ≤0.002mm, which is more than 50% higher than the traditional process (roundness error ≥0.004mm); the surface roughness is reduced to below Ra0.01μm, reaching the level of ultra-precision machining, and meeting the precision requirements of high-end fields such as aerospace. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the combined structure of the grinding tool, base, and ball cap in the high-precision ball hinge spherical grinding process of the present invention; Figure 2 This is a schematic diagram of the combination structure of the grinding tool and the base in the high-precision ball hinge spherical grinding process of the present invention; Figure 3 This is a schematic diagram of the combination structure of the grinding tool and the ball cap in the high-precision ball hinge spherical grinding process of the present invention; Figure 4 This is a schematic diagram of the grinding tool used in the high-precision ball hinge spherical grinding process of the present invention; Figure 5This is a cross-sectional view of the grinding tool used in the high-precision ball hinge spherical grinding process of the present invention; Figure 6 This is a structural layout diagram of the multi-axis linkage grinding equipment for the high-precision ball hinge spherical grinding process of the present invention; In the picture: 1-Base, 2-Ball cap, 3-Grinding tool, 4-Handle, 5-Tool head, 6-Multi-axis linkage grinding equipment, 7-Rotating shaft, 8-Ball hinge clamp, 9-Control system, 10-Intelligent monitoring system. Detailed Implementation

[0017] The present invention will be further described in detail below through specific embodiments. The following embodiments are merely descriptive and not limiting, and should not be used to limit the scope of protection of the present invention.

[0018] like Figures 1 to 6 As shown, a high-precision ball hinge spherical grinding process involves grinding the inside of the base 1 and the ball cap 2 using a grinding tool 3 to form a ball neck. The process includes the following steps: Step 1: Preparation of the multi-axis linkage grinding equipment 6 and grinding tools 3: Install the handle 4 of the grinding tool 3 on the rotating shaft 7 of the multi-axis linkage grinding equipment 6, install the tool head 5 in the base 1 and the ball pressure cover 2, and install the base 1 on the multi-axis linkage grinding equipment 6 through the ball hinge clamp 8. Check and debug the control system 9 of the multi-axis linkage grinding equipment 6; calibrate and debug the sensors of the intelligent detection system of the multi-axis linkage grinding equipment 6. Step 2, Parameter Settings: Parameter setting: Based on the material, size, and precision requirements of the ball joint, initial grinding parameters are input into the multi-axis linkage control system 9 and the intelligent monitoring system 10, including the movement speed, acceleration, grinding pressure range, and grinding time of each motion axis. Simultaneously, parameter thresholds and adaptive control strategies are set for the intelligent monitoring system 10 to ensure the safe and efficient execution of the grinding process.

[0019] Step 3: Start the multi-axis linkage grinding equipment 6 to grind the base 1 and the ball cap 2. The multi-axis linkage system drives the grinding tool 3 to grind the inside of the base 1 and the ball cap 2 according to the preset trajectory. The grinding fluid is continuously transported to the grinding area inside the base 1 and the ball cap 2 through the cooling channel. During the grinding process, the intelligent monitoring system 10 collects grinding pressure, temperature, and wear data of the grinding tool 3 in real time and transmits the data to the control system 9. When the grinding pressure exceeds the set threshold, the control system 9 reduces the movement speed of the grinding tool 3. When the wear of a certain area of ​​the grinding tool 3 is detected to exceed a certain level, the system automatically adjusts the grinding time and pressure distribution of that area.

[0020] Step 4, Quality Inspection: After grinding, a high-precision testing device is used to test the spherical roundness, cylindricity shape accuracy, and surface roughness of the ball neck formed by grinding inside the base 1 and ball cap 2. The test results are compared with the preset accuracy requirements. If the test results meet the requirements, the processing is completed; if they do not meet the requirements, the control system 9 analyzes the cause and adjusts the process parameters based on the test data and the grinding process data recorded by the intelligent detection system, and performs grinding again.

[0021] An advanced multi-axis linkage grinding equipment 6 and control system 9 are employed to achieve complex and precise relative motion between the grinding tool 3 and the ball joint. Through precise control of the coordinated movement of the X, Y, Z axes and the rotary axis 7, the grinding tool 3 can grind the spherical surface of the ball joint according to a preset complex trajectory. For example, during the grinding process, the X and Y axes control the movement of the grinding tool 3 in the horizontal plane, the Z axis controls the up-and-down feed of the grinding tool 3, and the rotary axis 7 causes the grinding tool 3 to rotate around the central axis of the ball joint during grinding. Simultaneously, in conjunction with the remote movement of other axes, a spiral grinding trajectory is formed. This complex grinding trajectory ensures that every point on the spherical surface of the ball joint is uniformly ground, effectively improving the roundness and surface roughness accuracy of the sphere. Compared with traditional processes, the roundness accuracy can be improved by more than 50%, and the surface roughness can be reduced to below Ra0.01μm.

[0022] 9-core architecture of the control system: Hardware configuration: It adopts a dual-core control architecture based on a PLC (Siemens S7-1500) and a motion controller (Panasonic A6N). The PLC is responsible for logic control and data interaction, while the motion controller is responsible for precise multi-axis motion control. It is equipped with an 8-axis servo drive system (X, Y, Z linear axes + A, B, C rotary axes + 7 auxiliary axes), with servo motor resolution ≥17 bits, linear axis positioning accuracy ≤0.001mm / m, and rotary axis 7 positioning accuracy ≤0.001°, ensuring precise execution of complex trajectories.

[0023] Trajectory planning algorithm: A NURBS (Non-Uniform Rational B-Spline) curve interpolation algorithm is used to smooth the grinding trajectory, with the distance between trajectory nodes ≤0.005mm, avoiding impact and vibration during movement. Through horizontal linkage of the X and Y axes, and coordinated feeding of the Z-axis and rotation axis 7, a spiral grinding trajectory is formed with a pitch of 0.1-0.3mm, ensuring that each point on the sphere is ground ≥3 times, improving grinding uniformity by more than 60%.

[0024] Motion control performance optimization: Dynamic error compensation: The motion error of each axis is calibrated using a laser interferometer, and an error compensation model is established to compensate for positioning error, backlash (compensation accuracy ≤ 0.0005 mm), and thermal deformation error (compensation response time ≤ 10 ms) in real time. After 2 hours of continuous grinding, the positioning error caused by thermal deformation of the equipment is controlled within 0.002 mm.

[0025] Multi-axis coordinated synchronous control: Electronic cam synchronization technology is adopted to ensure that the synchronization error of each axis is ≤0.001mm, ensuring that the grinding tool 3 moves smoothly along the preset trajectory. For the grinding needs of different areas of the sphere (polar point, equatorial surface), the movement speed and acceleration of each axis are dynamically adjusted. The speed in the polar area is reduced by 30% to avoid surface damage caused by concentrated grinding pressure.

[0026] Through multi-axis linkage control, the spherical neck of the ball hinge has a roundness error of ≤0.002mm, which is more than 50% higher than the traditional process (roundness error ≥0.004mm); the surface roughness is reduced to below Ra0.01μm, reaching the level of ultra-precision machining and meeting the precision requirements of high-end fields such as aerospace.

[0027] A smart sensor and automated control system 9 are introduced to monitor key parameters in the grinding process in real time, such as grinding pressure, temperature, and the wear degree of the grinding tool 3. Sensor parameters are transmitted to the acquisition module, which then sends them to the central processing unit for processing. The central processing unit processes the data and transmits control commands. The actuators adjust the operating parameters of the grinding equipment according to these commands, such as the X-axis motor driver controlling the X-axis movement. Based on this real-time data, the system can automatically adjust the grinding process parameters to achieve adaptive grinding control. When the sensor detects excessively high grinding pressure in a certain area, the system automatically adjusts the movement speed and feed rate of the grinding tool 3 to reduce the grinding pressure in that area and avoid spherical damage due to excessive pressure. When wear is detected in the grinding tool 3, the system automatically adjusts the compensation amount of the grinding tool 3 according to the degree of wear to ensure the stability and consistency of the grinding process, thereby guaranteeing the stability and reliability of the spherical surface machining quality of the ball hinge and reducing the scrap rate.

[0028] Hardware configuration and principle of the detection system: Sensor Selection and Layout: Three types of core sensors are deployed on the grinding equipment: a strain gauge pressure sensor (measurement range 0-500N, accuracy ±0.5%FS) to detect grinding pressure in real time; an infrared temperature sensor (measurement range 0-500℃, accuracy ±1℃) to monitor the temperature of the grinding area; and a laser displacement sensor (measurement range 0-20mm, accuracy ±0.001mm) to detect the wear of the grinding tools. The sensor sampling frequency is ≥1000Hz to ensure real-time data transmission.

[0029] Data Acquisition and Transmission: Sensor data is collected through a distributed data acquisition module (Advantech USB-4711) and transmitted to the central processing unit (Intel Core i7-12700K) via EtherCAT bus, with a transmission latency of ≤1ms, ensuring no data loss and no delay.

[0030] Adaptive control algorithm and logic: Core control algorithm: A hybrid algorithm of PID and fuzzy control is adopted to dynamically adjust process parameters based on real-time detected pressure, temperature, and wear data of the grinding tool 3. For example, when the grinding pressure exceeds the set threshold (300N), the algorithm automatically reduces the feed rate of the grinding tool 3 (adjustment step size 0.0005mm) and the movement speed (adjustment range 5-10%) until the pressure recovers to a reasonable range (150-250N).

[0031] Adaptive wear compensation for grinding tool 3: A wear model for grinding tool 3 is established. Based on the wear amount detected by the laser displacement sensor (compensation is activated when ≥0.003mm), the Z-axis feed rate and grinding time are automatically adjusted to ensure consistent grinding depth. Simultaneously, when the wear amount reaches 0.01mm, the system issues a warning to replace grinding tool 3, preventing a decline in machining quality due to excessive wear of grinding tool 3.

[0032] 9. Reliability assurance of the control system: Redundancy design: Key control modules (such as motion controllers and data acquisition modules) adopt dual redundancy configuration. When the main module fails, the backup module can seamlessly switch within 50ms to ensure the grinding process continues and avoid workpiece scrap.

[0033] Fault diagnosis and early warning: The system has a built-in fault diagnosis algorithm that can monitor the status of key components such as sensors, servo motors, and cooling systems in real time. When an abnormality occurs (such as sensor signal loss or motor overload), it will immediately issue an audible and visual alarm and record the fault information. At the same time, it will automatically stop the machine to protect the workpiece and equipment. The fault diagnosis accuracy rate is ≥95%.

[0034] Through intelligent detection and adaptive adjustment, the scrap rate has been reduced from 8-12% in traditional processes to below 2%, and the batch processing quality consistency has been improved by more than 70%, significantly reducing production costs.

[0035] like Figures 1 to 5 As shown, the grinding tool 3 includes a shank 4 and a cutting head 5.

[0036] Optimization of the three core structures of grinding tools: Material selection and performance matching: For commonly used alloy materials (such as titanium alloy and high-strength stainless steel) of ball hinge base 1 and ball cap 2, WC-Co series cemented carbide is selected as the matrix of grinding tool 3. This material has a hardness of HRA89-93, wear resistance is 5-8 times higher than ordinary high-speed steel, and it also has good toughness to prevent the grinding tool 3 from chipping during grinding. By adding TiC and / or TaC alloying elements, the high-temperature stability of grinding tool 3 is further improved, making it suitable for the working temperature range of 150-300℃ during grinding.

[0037] Modular structural design: The tool holder 4 adopts the ISO standard BT40 / BT50 interface, which can be directly adapted to the multi-axis linkage grinding equipment 6 without additional adaptation and modification, reducing equipment compatibility costs. The cutter head 5 adopts a detachable structure. According to the inner spherical surface size of different specifications of ball joints (Φ10-Φ100mm), a spherical cutter head 5 with a corresponding radius of curvature is designed and fixed to the tool holder 4 through a precision thread connection, with a repeatability accuracy ≤0.002mm.

[0038] The grinding section features a precision design: the grinding area of ​​the tool head 5 adopts a spherical structure that matches the hemispherical surface 1:1, with a sphericity error ≤0.001mm, ensuring full contact with the workpiece during grinding. Surface roughness is controlled below Ra0.005μm, and microscopic burrs are removed through ultra-precision grinding to avoid scratching the workpiece surface. A chemical nickel-diamond composite plating process is used, embedding diamond particles with a diameter of 5-20μm on the grinding surface, with a plating thickness of 5-8μm and a bonding force ≥50N / mm², significantly improving grinding efficiency and durability. A single grinding tool 3 can continuously process 500-800 workpieces.

[0039] Chip removal channels and cooling passages: Chip removal grooves: 3-6 spiral arc-shaped chip removal grooves are evenly arranged on the spherical surface of the grinding tool. The grooves are 8-12mm wide, 2-3mm deep, and have a spiral angle of 15-20°. They form a synergistic flow guiding effect with the grinding trajectory, so that the grinding chips (particle size ≤5μm) can be discharged quickly and avoid accumulating in the grinding area to form secondary scratches.

[0040] Cooling Channel: A through-type cooling channel is designed inside the tool holder 4 and the tool head 5. The outlet of the cooling channel is connected to the chip removal groove. The grinding fluid (using emulsion or cutting oil, viscosity 20-40 mm² / s) is delivered to the grinding area through a high-pressure pump (pressure 0.8-1.2 MPa), with the flow rate controlled at 10-20 L / min. The cooling channel outlet adopts a fan-shaped spray structure, with a spray coverage area ≥ 120% of the grinding area, ensuring uniform coverage of the grinding fluid, reducing the grinding temperature by 30-40%, and simultaneously reducing wear on the grinding tool 3, extending the life of the grinding tool 3 by 20-30%.

[0041] Precise adaptation of 3 parameters for grinding tools: Based on the characteristics of different processed materials, a parameter database for grinding tools was established: for titanium alloys, the cutting speed was set to 8-12 m / min, the feed rate to 0.005-0.01 mm / r, and the grinding depth to 0.001-0.003 mm; for high-strength stainless steel, the cutting speed was set to 10-15 m / min, the feed rate to 0.008-0.012 mm / r, and the grinding depth to 0.002-0.004 mm. Through parameter optimization, a balance between grinding efficiency and processing quality was achieved, resulting in a 40-60% improvement in processing efficiency compared to traditional grinding tools.

[0042] Example: A high-precision ball hinge spherical grinding process involves grinding the interior of the base 1 and the ball cap 2 using a grinding tool 3 to form a ball neck. The process includes the following steps: Step 1: Preparation of the multi-axis linkage grinding equipment 6 and grinding tools 3: The handle 4 of the grinding tool 3 is installed on the rotating shaft 7 of the multi-axis linkage grinding equipment 6. The tool head 5 is installed inside the base 1 and the ball cap 2. The base 1 is installed on the multi-axis linkage grinding equipment 6 via a ball hinge clamp 8 and secured with a torque wrench to a torque of 45-55 Nm to ensure a firm installation. Each motion axis is adjusted using a laser interferometer to compensate for positioning errors and backlash. The pressure, temperature, and laser displacement sensors are calibrated to ensure detection accuracy. The grinding fluid flow rate and pressure are adjusted to ensure unobstructed cooling channels. The control system 9 of the multi-axis linkage grinding equipment 6 is checked and adjusted; the sensors of the intelligent detection system of the multi-axis linkage grinding equipment 6 are calibrated and adjusted.

[0043] Step 2, Parameter Settings: Based on the material, size, and precision requirements of the ball joint, the initial grinding parameters are input into the control system 9 and intelligent monitoring system 10 of the multi-axis linkage grinding equipment 6: linear axis movement speed 5-8m / min, acceleration 0.5-1m / s², grinding pressure 150-250N, and grinding time 10-20min; sensor thresholds are set: pressure upper limit 300N, temperature upper limit 300℃, and grinding tool 3 wear warning value 0.01mm; adaptive control strategies are set (such as parameter adjustment range when pressure exceeds the threshold).

[0044] Step 3: Start the multi-axis linkage grinding equipment 6 to grind the base 1 and the ball cap 2. The multi-axis linkage system drives the grinding tool 3 to grind the inside of the base 1 and the ball cap 2 according to the spiral trajectory generated by NURBS interpolation. The grinding fluid is continuously transported to the grinding area inside the base 1 and the ball cap 2 through the cooling channel. During the grinding process, the intelligent monitoring system 10 collects grinding pressure, temperature, and wear data of the grinding tool 3 in real time and transmits the data to the control system 9. When the grinding pressure exceeds the set threshold, the control system 9 reduces the movement speed of the grinding tool 3. When the grinding pressure at the equatorial surface is detected to reach 280N, the control system 9 automatically reduces the feed rate from 0.008mm / r to 0.006mm / r and the speed from 6m / min to 5.5m / min to ensure that the pressure remains stable within a reasonable range. Step 4, Quality Inspection: After grinding, a coordinate measuring machine (CMM) with an accuracy of ≤0.001mm is used to inspect the spherical roundness and cylindricity of the ball neck formed inside the base 1 and ball cap 2. An atomic force microscope (AFM) with a resolution of 0.001μm is used to inspect the surface roughness of the ball neck formed inside the base 1 and ball cap 2. The inspection results are compared with the preset accuracy requirements. If the inspection results meet the preset requirements (roundness ≤0.002mm, Ra≤0.01μm), the processing is completed. If the inspection results do not meet the requirements, the control system 9 automatically retrieves the grinding process data, analyzes the cause of the error, adjusts the process parameters, and performs a second grinding until the standard is met.

[0045] Based on the material properties of the workpiece base 1 and the ball cap 2, the grinding tool 3 requires high hardness, high wear resistance, and good toughness. Commonly used cemented carbide materials are selected to reduce the cost of the grinding tool 3. The overall structural design of the grinding tool 3 ensures stability and rigidity during the grinding process. The tool holder 4 is designed as a universal standard structure for easy installation on a multi-axis linkage grinding device 6, while the tool head 5 is specially designed according to the shape of the inner spherical surface of the base 1 and the ball cap 2. The grinding part is the core of the grinding tool 3; its shape and size directly affect the grinding effect. It is designed to be a sphere that matches the hemispherical surface, ensuring full contact with the spherical surface during grinding for uniform grinding. The surface roughness of the grinding part should be low to reduce scratches on the spherical surface. Diamond particles can be embedded in the grinding part using electroplating or sintering methods to improve the grinding effect and surface quality. The chip removal groove and cooling channel design eliminate heat and debris generated during the grinding process. A uniform arc-shaped chip removal groove is designed on the spherical surface of the grinding tool 3 to prevent debris from accumulating in the grinding area and affecting the grinding effect. The grinding fluid can be delivered to the grinding area through the chip removal groove, promoting grinding effect, reducing area temperature, reducing wear on the grinding tool 3, and extending the life of the grinding tool 3. The grinding tool 3 parameters are optimized based on factors such as the hardness of the grinding material and the performance of the grinding equipment. Parameters such as cutting speed, feed rate, and grinding depth must be properly matched to achieve the best grinding effect. This unique grinding tool 3 design allows for targeted processing of different areas of the ball joint surface simultaneously in a single grinding process, greatly improving grinding efficiency and precision.

[0046] Although embodiments and drawings of the present invention have been disclosed for illustrative purposes, those skilled in the art will understand that various substitutions, variations and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A high-precision ball hinge spherical grinding process, characterized in that: The base (1) and the inside of the ball cap (2) are ground by a grinding tool (3) to form a ball neck, including the following steps: Step 1: Preparation of multi-axis linkage grinding equipment (6) and grinding tools (3): Install the handle (4) of the grinding tool (3) on the rotating shaft (7) of the multi-axis linkage grinding equipment (6), install the cutting head (5) in the base (1) and the ball pressure cover (2), install the base (1) on the multi-axis linkage grinding equipment (6) through the ball hinge clamp (8), check and debug the control system (9) of the multi-axis linkage grinding equipment (6); calibrate and debug the sensors of the intelligent detection system of the multi-axis linkage grinding equipment (6); Step 2, Parameter Settings: According to the material, size and precision requirements of the ball joint, the initial grinding parameters are input into the control system (9) and intelligent monitoring system (10) of the multi-axis linkage grinding equipment (6): linear axis movement speed 5-8m / min, acceleration 0.5-1m / s², grinding pressure 150-250N, grinding time 10-20min; sensor thresholds are set: pressure upper limit 300N, temperature upper limit 300℃, grinding tool (3) wear warning value 0.01mm; adaptive control strategy is set. Step 3: Start the multi-axis linkage grinding equipment (6) to grind the base (1) and the ball cap (2). The multi-axis linkage system drives the grinding tool (3) to grind the inside of the base (1) and the ball cap (2) according to the spiral trajectory generated by NURBS interpolation. The grinding fluid is continuously transported to the grinding area inside the base (1) and the ball cap (2) through the cooling channel. During the grinding process, the intelligent monitoring system (10) collects grinding pressure, temperature and wear data of the grinding tool (3) in real time and transmits the data to the control system (9); when the grinding pressure exceeds the set threshold, the control system (9) reduces the movement speed of the grinding tool (3); when the grinding pressure on the equatorial surface is detected to reach 280N, the control system (9) automatically reduces the feed rate from 0.008mm / r to 0.006mm / r and the speed from 6m / min to 5.5m / min. Step 4, Quality Inspection: After grinding, a coordinate measuring machine with an accuracy of ≤0.001mm is used to test the spherical roundness and cylindricity of the ball neck formed by grinding inside the base (1) and the ball cap (2); an atomic force microscope with a resolution of 0.001μm is used to test the surface roughness of the ball neck formed by grinding inside the base (1) and the ball cap (2); the test results are compared with the preset accuracy requirements. If the test results meet the preset requirements, with roundness ≤0.002mm and Ra≤0.01μm, the processing is completed; if the test results do not meet the requirements, the control system (9) automatically retrieves the grinding process data, analyzes the cause of the error, adjusts the process parameters, and performs a second grinding until the standard is met.

2. The high-precision ball hinge spherical grinding process according to claim 1, characterized in that: The grinding tool (3) includes a handle (4) and a cutting head (5); the handle (4) and the cutting head (5) are made of WC-Co series cemented carbide with a hardness of HRA89-93 and wear resistance 5-8 times higher than that of ordinary high-speed steel. TiC or / and TaC alloying elements are added to adapt to the working temperature range of 150-300℃ in the grinding process.

3. The high-precision ball hinge spherical grinding process according to claim 2, characterized in that: The tool holder (4) adopts the ISO standard BT40 / BT50 interface, which can be directly adapted to the multi-axis linkage grinding equipment (6).

4. The high-precision ball hinge spherical grinding process according to claim 2, characterized in that: The cutter head (5) adopts a detachable structure. According to the spherical surface size of the inner ball joint of different specifications Φ10-Φ100mm, the spherical cutter head (5) with the corresponding radius of curvature is fixedly connected to the cutter shank (4) by thread, and the repeatability of positioning accuracy is ≤0.002mm.

5. The high-precision ball hinge spherical grinding process according to claim 4, characterized in that: The grinding area of ​​the cutting head (5) adopts a spherical structure that matches the hemispherical surface 1:1, with a sphericity error ≤0.001mm and a surface roughness controlled below Ra0.005μm. It adopts a chemical nickel-diamond composite coating process, embedding diamond particles with a particle size of 5-20μm on the grinding surface, with a coating thickness of 5-8μm and a bonding force ≥50N / mm².

6. The high-precision ball hinge spherical grinding process according to claim 5, characterized in that: The cutter head (5) has 3-6 spiral arc-shaped chip removal grooves evenly arranged on its spherical surface. The groove width is 8-12mm, the groove depth is 2-3mm, and the spiral angle is 15-20°.

7. The high-precision ball hinge spherical grinding process according to claim 6, characterized in that: The tool holder (4) and the tool head (5) are designed with a through-type cooling channel. The outlet of the cooling channel is connected to the chip removal groove. The outlet of the cooling channel adopts a fan-shaped spray structure, and the spray coverage area is ≥120% of the grinding area.

8. The high-precision ball hinge spherical grinding process according to claim 2, characterized in that: Establish a database of grinding tool parameters (3): Titanium alloy material, cutting speed set to 8-12m / min, feed rate 0.005-0.01mm / r, grinding depth 0.001-0.003mm; High-strength stainless steel, cutting speed 10-15m / min, feed rate 0.008-0.012mm / r, grinding depth 0.002-0.004mm.

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