Grinding machine precision control method and system

Abstract

This application relates to a grinding machine precision control method and system, belonging to the technical field of grinding machine control. The method includes acquiring basic workpiece parameters and grinding machine machining parameters; quantifying a preset grinding side temperature based on the basic workpiece parameters and grinding machine machining parameters to generate a grinding side temperature sequence; performing temperature mirror mapping based on the grinding side temperature sequence to generate non-grinding side temperature control parameters; and controlling a preset temperature control unit to control the workpiece temperature according to the non-grinding side temperature control parameters to achieve temperature symmetry between the grinding and non-grinding sides of the workpiece. This application improves the grinding efficiency of a surface grinder.

Description

Technical Field

[0001] This application relates to the technical field of grinding machine control, and in particular to a grinding machine precision control method and system. Background Technology

[0002] A grinding machine is a machine tool that uses abrasives to cut the surface of a workpiece. It is mainly used to improve the dimensional accuracy, geometric accuracy and surface finish of workpieces, and is a key piece of equipment for precision machining in mechanical manufacturing.

[0003] In related technologies, surface grinders typically use a flipping grinding method to control the thermal deformation of workpieces. When grinding one side of a workpiece, the heat generated by grinding is mainly concentrated on the surface layer of that side. When the accumulated temperature is high, a temperature gradient will be generated between that side and the other side of the workpiece, causing the workpiece to expand and deform. Therefore, after rough grinding one side, the workpiece is flipped over and the other side is ground to eliminate the temperature gradient between the two sides of the workpiece and reduce the thermal deformation of the workpiece.

[0004] Regarding the aforementioned technologies, when a surface grinder uses the turning grinding method to grind a workpiece, it requires multiple stops, turning, clamping, and alignment, resulting in low grinding efficiency of the surface grinder and room for improvement. Summary of the Invention

[0005] In order to improve the grinding efficiency of surface grinders on workpieces, this application provides a grinding machine accuracy control method and system.

[0006] In a first aspect, this application provides a method for controlling the precision of a grinding machine, which adopts the following technical solution: A method for controlling the accuracy of a grinding machine, comprising: Collect basic workpiece parameters and grinding machine machining parameters; The temperature of the pre-set grinding side is quantified based on the workpiece's basic parameters and the grinding machine's processing parameters to generate a grinding side temperature sequence. Temperature mirror mapping is performed based on the temperature sequence on the grinding side to generate temperature control parameters on the non-grinding side. The workpiece temperature is controlled by a preset temperature control unit based on the temperature control parameters of the non-grinding side, so as to achieve temperature symmetry between the grinding side and the non-grinding side of the workpiece.

[0007] Optionally, the step of quantifying the preset temperature of the grinding side based on the workpiece's basic parameters and the grinding machine's machining parameters to generate a grinding side temperature sequence includes: Collect the grinding side coordinates and the current time; The grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed, and grinding wheel diameter are determined based on the grinding side coordinates, current time, and grinding machine processing parameters. The grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed and grinding wheel diameter are analyzed to generate the instantaneous heat flux density on the grinding side. The workpiece's thermal diffusivity, thermal conductivity, density, and specific heat capacity are determined based on its basic parameters. Based on a preset real-time grinding temperature model, the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side are calculated to generate a grinding side temperature sequence.

[0008] Optionally, the step of analyzing the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed, and grinding wheel diameter to generate the instantaneous heat flux density on the grinding side includes: Based on the preset grinding force model, the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, and real-time grinding wheel linear speed are calculated to generate real-time tangential grinding force. The product of real-time tangential grinding force, real-time linear velocity of the grinding wheel, and preset grinding temperature rise coefficient is calculated to generate real-time grinding heat power. The real-time grinding depth, real-time grinding width, and grinding wheel diameter are analyzed to generate the real-time grinding area; Calculate the quotient of real-time grinding heat power and real-time grinding area to generate the instantaneous heat flux density on the grinding side; The expression for the grinding force model is: , In the formula, For real-time tangential grinding force, For grinding specific energy coefficient, For real-time grinding depth, For real-time grinding width, For the real-time speed of the workpiece, This represents the real-time linear velocity of the grinding wheel.

[0009] Optionally, the grinding real-time temperature model includes a grinding heating model and a reference temperature model. The step of calculating the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side based on the preset grinding real-time temperature model to generate the grinding side temperature sequence includes: The instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side are calculated based on the grinding temperature rise model to generate the temperature change on the grinding side. Real-time workpiece temperature, real-time coolant temperature, and real-time grinding machine temperature are collected based on grinding side coordinates. The real-time workpiece temperature, real-time coolant temperature, and real-time grinding machine temperature are calculated based on the reference temperature model to generate the grinding side reference temperature. The sum of the temperature change on the grinding side and the reference temperature on the grinding side is calculated to generate the real-time temperature on the grinding side. The grinding side temperature sequence is generated by integrating the grinding side coordinates and the current time with the real-time grinding side temperature.

[0010] Optionally, the step of performing temperature mirror mapping based on the grinding-side temperature sequence to generate non-grinding-side temperature control parameters includes: Determine the grinding side coordinates and current time based on the grinding side temperature sequence; Coordinate transformation is performed based on the grinding side coordinates to generate the non-grinding side coordinates; Collect the thermal conduction hysteresis time; The real-time temperature of the non-grinding side is determined by searching the temperature sequence on the grinding side based on the grinding side coordinates, thermal hysteresis time, and current time. Correlate the non-grinding side coordinates and the real-time temperature of the non-grinding side to generate non-grinding side temperature control parameters.

[0011] Optionally, the steps for acquiring the thermal conduction hysteresis time include: Determine the thermal diffusivity and thickness of the workpiece based on its basic parameters. The thermal diffusivity and thickness of the workpiece are calculated based on a preset thermal conduction hysteresis model to generate the thermal conduction hysteresis time. The expression for the thermal conduction hysteresis model is: , In the formula, For heat conduction hysteresis time, For workpiece thickness, This represents the thermal diffusivity of the workpiece.

[0012] Optionally, the step of determining the real-time temperature of the non-grinding side by searching the grinding side temperature sequence based on the grinding side coordinates, thermal hysteresis time, and current time includes: Calculate the difference between the current time and the thermal hysteresis time to generate the thermal compensation time; The ideal non-grinding side temperature is determined by searching the grinding side temperature sequence based on the grinding side coordinates and thermal compensation time. Determine the heat dissipation compensation coefficient based on the non-grinding side coordinates; Calculate the product of the heat dissipation compensation coefficient and the ideal non-grinding side temperature to generate the real-time temperature of the non-grinding side.

[0013] Optionally, the step of determining the heat dissipation compensation coefficient based on the non-grinding side coordinates includes: Determine the coordinate edge distance based on the non-grinding side coordinates; The distance to the coordinate edge is calculated based on the preset heat dissipation compensation model to generate the heat dissipation compensation coefficient. The expression for the heat dissipation compensation model is: , In the formula, For heat dissipation compensation coefficient, For the preset compensation gain coefficient, Distance to coordinate edge The preset center-edge distance.

[0014] Secondly, this application provides a grinding machine precision control system, which adopts the following technical solution: A grinding machine precision control system includes: The data acquisition module is used to acquire basic workpiece parameters and grinding machine processing parameters; A memory for storing a program for a grinding machine precision control method as described in any of the preceding claims; The processor and the program in the memory can be loaded and executed by the processor to implement a grinding machine precision control method as described in any of the above.

[0015] In summary, this application includes at least one of the following beneficial technical effects: 1. The temperature on the grinding side is quantified by the workpiece's basic parameters and the grinding machine's processing parameters to obtain the grinding side temperature sequence. Then, temperature mirror mapping is performed based on the grinding side temperature sequence to determine the non-grinding side temperature control parameters. The non-grinding side temperature control parameters are used to control the temperature control unit to control the workpiece temperature, eliminate the temperature gradient of the workpiece during the grinding process, reduce workpiece deformation, improve the grinding accuracy of the grinding machine, and eliminate the need for multiple machine stops, flips, clamping, and alignment, thereby improving the grinding efficiency of the grinding machine on the workpiece. 2. By determining the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, workpiece real-time speed, grinding wheel real-time linear speed, and grinding wheel diameter using the grinding side coordinates, current time, and grinding machine processing parameters, the instantaneous heat flux density of the workpiece at the grinding side coordinates at the current time is obtained after analyzing the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, workpiece real-time speed, grinding wheel real-time linear speed, and grinding wheel diameter. Then, based on the grinding real-time temperature model, the instantaneous heat flux density of the grinding side, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity are calculated to generate a grinding side temperature sequence, thereby improving the accuracy and comprehensiveness of the grinding side temperature sequence. 3. By transforming the coordinates of the grinding side to obtain the coordinates of the non-grinding side, and then searching in the grinding side temperature sequence based on the grinding side coordinates, thermal hysteresis time and current time, the real-time temperature of the non-grinding side is obtained. Thus, the non-grinding side coordinates and the real-time temperature of the non-grinding side are correlated to generate non-grinding side temperature control parameters. This allows for precise temperature control of different positions on the non-grinding side of the workpiece, reducing the temperature gradient during the workpiece grinding process, reducing workpiece thermal deformation, and thereby improving the grinding accuracy of the grinding machine. Attached Figure Description

[0016] Figure 1 This is a flowchart of a grinding machine precision control method according to an embodiment of this application.

[0017] Figure 2 This is a flowchart of the steps in this application embodiment to quantify the temperature of the preset grinding side based on the workpiece basic parameters and grinding machine processing parameters to generate a grinding side temperature sequence.

[0018] Figure 3 This is a flowchart of the steps in this application embodiment to analyze the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed and grinding wheel diameter to generate the instantaneous heat flux density on the grinding side.

[0019] Figure 4 This is a flowchart of the steps in this application embodiment to calculate the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side based on a preset real-time grinding temperature model, in order to generate a grinding side temperature sequence.

[0020] Figure 5 This is a flowchart of the steps in this application embodiment to generate non-grinding side temperature control parameters by performing temperature mirror mapping based on the grinding side temperature sequence.

[0021] Figure 6 This is a flowchart of the steps for collecting thermal conduction hysteresis time in the embodiments of this application.

[0022] Figure 7 This is a flowchart of the steps in this application embodiment to determine the real-time temperature of the non-grinding side by searching in the temperature sequence of the grinding side based on the grinding side coordinates, thermal hysteresis time, and current time.

[0023] Figure 8 This is a flowchart of the steps for determining the heat dissipation compensation coefficient based on the non-grinding side coordinates in the embodiments of this application. Detailed Implementation

[0024] To make the purpose, technical solution, and advantages of this application clearer, the following description is provided in conjunction with the appendix. Figures 1 to 8 The present application will be further described in detail below with reference to embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the scope of the application.

[0025] Reference Figure 1 This application discloses a method for controlling the precision of a grinding machine, comprising the following steps: Step S100: Collect the basic parameters of the workpiece and the machining parameters of the grinding machine.

[0026] Among them, the basic parameters of the workpiece refer to the parameters related to the grinding temperature rise during the grinding process of the workpiece on the grinding machine, including the workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, workpiece specific heat capacity and workpiece thickness. By collecting the basic parameters of the workpiece, data support is provided for subsequent analysis of the specific temperature of the workpiece grinding side during the grinding process on the grinding machine.

[0027] The thermal diffusivity of a workpiece refers to the speed at which the temperature field is conducted within the workpiece, reflecting the rate of heat transfer from the workpiece material. It is obtained by calculating the quotient of the product of the workpiece's thermal conductivity, density, and specific heat capacity. The thermal conductivity of a workpiece refers to the amount of heat that can be transferred per unit area per unit time, reflecting the thermal conductivity of the workpiece material. The density of a workpiece refers to the density of all materials within the workpiece. The specific heat capacity of a workpiece refers to the amount of heat required to achieve a unit temperature change per unit mass of workpiece material, reflecting the workpiece material's ability to store heat. The thickness of a workpiece refers to the vertical distance between the ground and unground sides, determining the path length for heat conduction on the ground side. The thermal diffusivity, thermal conductivity, density, and specific heat capacity of a workpiece are obtained by the processing terminal from a database that corresponds one-to-one with the material's thermal properties, based on the material type input by the operator. The workpiece thickness is measured by the operator using measuring tools and uploaded to the processing terminal. Upon receiving the thermal diffusivity, thermal conductivity, density, specific heat capacity, and thickness, the processing terminal integrates these data into a dataset according to the set data order for easy access later.

[0028] Grinding machine processing parameters refer to parameters related to grinding temperature during the grinding process, including real-time grinding coordinates, grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed, and grinding wheel diameter. By collecting grinding machine processing parameters, data support is provided for subsequent analysis of the specific temperature of the workpiece grinding side during the grinding process.

[0029] Grinding real-time coordinates refer to the real-time coordinates of the grinding wheel center, which are obtained by the feed axis encoder of the grinding machine control system detecting the position of the grinding wheel.

[0030] The grinding specific energy coefficient refers to the total energy required to grind a unit volume of workpiece. It reflects the ratio of energy input to material removal during the grinding process and is obtained through grinding force calibration tests. The specific process is as follows: using a grinding machine, grinding wheel, and workpiece that are exactly the same as those used in the machining process, multiple sets of grinding parameters with gradient changes are set, such as grinding depth, grinding width, workpiece speed, and grinding wheel linear speed. Each set of grinding parameters is repeatedly tested multiple times. During the process, the grinding force and the volume removed are measured. The quotient of the product of the grinding force and the grinding wheel linear speed and the product of the volume removed, grinding depth, grinding width, and workpiece speed is then used to obtain the grinding specific energy coefficient calibrated for that set of parameters. Finally, the average value of the grinding specific energy coefficients obtained from all sets of parameter calibrations is used to obtain the final grinding specific energy coefficient.

[0031] Real-time grinding depth refers to the depth value removed by the grinding machine on the grinding side of the workpiece in each grinding cycle. The specific value is determined by the operator according to the requirements, and will not be elaborated here.

[0032] Real-time grinding width refers to the width of the workpiece being ground by the grinding machine. It is planned by the operator based on the specific required grinding width of the workpiece and the width of the grinding wheel to ensure that the grinding wheel completes the grinding with the fewest axial movements. For example, if the specific required grinding width is 100 mm and the maximum width of the grinding wheel is 500 mm, then the real-time grinding width is 500 mm.

[0033] The real-time speed of the workpiece refers to the speed of the workpiece during the grinding process, which is obtained by detecting the speed of the worktable carrying the workpiece by the feed axis encoder of the grinding machine control system.

[0034] The real-time linear speed of the grinding wheel refers to the tangential motion speed of the grinding wheel. It is obtained by collecting the rotational speed of the grinding wheel through the rotary encoder of the grinding machine control system and by calculating the quotient between the product of the rotational speed, the grinding wheel diameter, and π and 60000.

[0035] The grinding wheel diameter refers to the maximum diameter of the grinding wheel. It is obtained by the operator using an outside micrometer to select multiple measuring points around the circumference of the grinding wheel for actual measurement. Finally, the average value of the measured values ​​is calculated, which is the grinding wheel diameter.

[0036] Step S101: Based on the workpiece basic parameters and grinding machine processing parameters, the preset temperature of the grinding side is quantified to generate a grinding side temperature sequence.

[0037] The grinding side refers to the surface of the workpiece that is to be ground.

[0038] Grinding side temperature sequence refers to the specific temperature of different grinding positions at different times on the workpiece side from the start of grinding to the current moment. It is obtained by the processing terminal after quantifying and processing the grinding side temperature based on the workpiece's basic parameters and the grinding machine's machining parameters. For specific methods, please refer to [link to relevant documentation]. Figure 2The steps involve determining the temperature sequence on the grinding side to identify the temperature gradient that grinding may cause to exist on the workpiece, providing reference data for subsequent temperature control on the non-grinding side to eliminate the temperature gradient.

[0039] Step S102: Perform temperature mirror mapping based on the grinding side temperature sequence to generate non-grinding side temperature control parameters.

[0040] Among them, the non-grinding side temperature control parameters refer to the specific temperatures at different locations on the non-grinding side. The non-grinding side refers to the surface on the workpiece corresponding to the grinding side. These parameters are obtained by the processing terminal through mirror mapping based on the temperature at different locations in the grinding side temperature sequence, using the center plane between the grinding and non-grinding sides as a symmetry reference. For specific methods, please refer to [reference needed]. Figure 5 The process involves determining the temperature control parameters for the non-grinding side to make the temperatures of the non-grinding side and the grinding side symmetrical, thereby eliminating the temperature gradient of the workpiece, reducing the thermal deformation of the workpiece, and thus improving the accuracy of the grinding machine.

[0041] Step S103: Control the workpiece temperature using a preset temperature control unit based on the non-grinding side temperature control parameters to achieve temperature symmetry between the grinding and non-grinding sides of the workpiece.

[0042] Among them, the temperature control unit refers to the device installed on the worktable to control the temperature of the non-grinding side of the workpiece so that the relative surface temperature of the workpiece is symmetrical. It can be an array-type PTC heating module or an infrared heating module, etc.

[0043] After determining the temperature control parameters for the non-grinding side, the corresponding sub-unit in the temperature control unit is determined based on the coordinates corresponding to the non-grinding side temperature control parameters. This allows the sub-unit to control the temperature of the non-grinding side using the temperature at the coordinates corresponding to the non-grinding side temperature control parameters, thereby offsetting the temperature gradient generated on the grinding side in the workpiece thickness direction. This ensures temperature symmetry between the grinding and non-grinding sides of the workpiece, suppressing thermal deformation of the workpiece and improving the accuracy of the grinding machine. Furthermore, it eliminates the need for operators to stop, rotate, clamp, and align the machine multiple times, thus improving the grinding efficiency of the workpiece.

[0044] Reference Figure 2 The steps for quantifying the preset temperature of the grinding side based on the workpiece's basic parameters and the grinding machine's processing parameters to generate a grinding side temperature sequence include: Step S200: Collect the grinding side coordinates and the current time.

[0045] Among them, the grinding side coordinates refer to the coordinates of all positions on the grinding side of the workpiece that can be ground. A plane coordinate system is established with the geometric center of the workpiece as the origin, so as to map the grinding area on the grinding side of the workpiece to the plane coordinate system, thereby determining the coordinates corresponding to the grinding area, which are the grinding side coordinates.

[0046] The current time refers to the time from the start of grinding to the present, which is obtained in real time by the system clock of the processing terminal.

[0047] Step S201: Determine the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, workpiece real-time speed, grinding wheel real-time linear speed, and grinding wheel diameter based on the grinding side coordinates, current time, and grinding machine processing parameters.

[0048] In this process, after determining the grinding side coordinates and the current time, the grinding machine control system updates the grinding machine processing parameters based on the real-time grinding coordinates corresponding to the current time. The processing terminal determines the coordinates being ground in the grinding side coordinates based on the real-time grinding coordinates corresponding to the grinding machine processing parameters, and then calls the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, workpiece real-time speed, grinding wheel real-time linear speed, and grinding wheel diameter in the grinding machine processing parameters. This provides data support for determining the specific temperature rise of the coordinates during the grinding process. For the remaining grinding side coordinates that are not being ground, the grinding side reference temperature is directly calculated according to the scheme in step S402, and the grinding side reference temperature is defined as the grinding side real-time temperature. The grinding side real-time temperature is integrated based on the grinding side coordinates and the current time to generate a grinding side temperature sequence.

[0049] The grinding specific energy coefficient, real-time grinding depth, real-time grinding width, workpiece real-time speed, grinding wheel real-time linear speed, and grinding wheel diameter in this step are consistent with the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, workpiece real-time speed, grinding wheel real-time linear speed, and grinding wheel diameter disclosed in step S100. They are obtained by the processing terminal from the grinding machine processing parameters according to the usage requirements.

[0050] Step S202: Analyze the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed, and grinding wheel diameter to generate the instantaneous heat flux density on the grinding side.

[0051] Among them, the instantaneous heat flux density on the grinding side refers to the heat transferred per unit area per unit time at the grinding location in the grinding side coordinate system. It reflects the intensity of heat input from grinding to the workpiece. It is obtained by the processing terminal after analyzing the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed, and grinding wheel diameter. The specific method is described in [reference needed]. Figure 3 The steps.

[0052] Step S203: Determine the workpiece's thermal diffusivity, thermal conductivity, density, and specific heat capacity based on the workpiece's basic parameters.

[0053] In this step, the workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity are consistent with those disclosed in step S100, and are obtained directly from the workpiece basic parameters by the processing terminal according to the usage requirements.

[0054] Step S204: Based on the preset real-time grinding temperature model, calculate the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density and workpiece specific heat capacity on the grinding side to generate a grinding side temperature sequence.

[0055] The grinding real-time temperature model refers to the model that calculates the real-time temperature of the grinding side coordinates. This model includes a grinding temperature rise model and a reference temperature model. The grinding temperature rise model calculates the temperature rise of the grinding side coordinates, and its specific expression is as follows: .

[0056] In the formula, For the temperature change on the grinding side, For the instantaneous heat flux density on the grinding side, For the thermal diffusivity of the workpiece, For the thermal conductivity of the workpiece, For workpiece density, This is the specific heat capacity of the workpiece.

[0057] This model is based on the surface temperature rise solution of a semi-infinite object heated by a constant heat flux density. The instantaneous heat flux density on the grinding side represents the intensity of the heat source, while the workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity represent the workpiece's heat conduction and dissipation capabilities. Through this model, the temperature rise of the grinding side coordinates under the combined effect of the heat source intensity and the material's heat conduction and dissipation capabilities can be accurately described.

[0058] The reference temperature model refers to the model used to calculate the reference temperature on the grinding side. Its specific expression is as follows: .

[0059] In the formula, This is the reference temperature for the grinding side. For real-time workpiece temperature, For real-time coolant temperature, For real-time grinding machine temperature, , and The weights of the preset real-time workpiece temperature, real-time coolant temperature, and real-time grinding machine temperature to the grinding side reference temperature are respectively determined. A heat balance ratio calibration test is carried out under the condition of no grinding heat source. The workpiece is installed on the worktable, and coolant at the set temperature is introduced. After the temperature reaches a stable state, the temperatures of the workpiece, worktable, and coolant are recorded. The weights of the three are obtained by solving the multiple linear regression method.

[0060] The grinding-side temperature sequence in this step is consistent with the grinding-side temperature sequence in step S101. It is calculated by the processing terminal based on the real-time grinding temperature model, using the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side. The specific method is described in [reference needed]. Figure 4 The steps.

[0061] Reference Figure 3 The steps for generating the instantaneous heat flux density on the grinding side include analyzing the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed, and grinding wheel diameter. Step S300: Based on the preset grinding force model, the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, and real-time grinding wheel linear speed are calculated to generate real-time tangential grinding force.

[0062] The grinding force model refers to the model for calculating the tangential grinding force of the grinding wheel on the workpiece, and its specific expression is as follows: .

[0063] In the formula, For real-time tangential grinding force, This is the grinding specific energy coefficient. For real-time grinding depth, For real-time grinding width, For the real-time speed of the workpiece, This represents the real-time linear velocity of the grinding wheel.

[0064] In this model, the grinding specific energy coefficient reflects the workpiece's resistance to grinding. The larger the real-time grinding depth and real-time grinding width, the greater the tangential force during workpiece grinding. The ratio of the real-time workpiece speed to the real-time grinding wheel speed reflects the influence of the speed matching between the workpiece feed and the grinding wheel speed on the tangential force. That is, the greater the workpiece speed and the smaller the grinding wheel speed, the more difficult it is to grind, and the greater the tangential force. Conversely, the smaller the workpiece speed and the greater the grinding wheel speed, the easier it is to grind, and the smaller the tangential force. The 0.75th power of the ratio reflects the nonlinear influence of speed parameters on the tangential force.

[0065] Real-time tangential grinding force refers to the grinding force of the grinding wheel on the workpiece in the tangential direction. The greater the real-time tangential grinding force, the greater the thermal power on the workpiece and the greater the corresponding heat flux density. It is calculated by the processing terminal by substituting the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, and real-time grinding wheel linear speed into the grinding force model, which provides data support for the subsequent determination of the grinding thermal power of the grinding machine on the workpiece.

[0066] Step S301: Calculate the product of real-time tangential grinding force, real-time linear velocity of grinding wheel and preset grinding temperature rise coefficient to generate real-time grinding heat power.

[0067] The grinding temperature rise coefficient refers to the proportion of heat introduced into the workpiece during the grinding process to the total grinding heat. Taking 0.6-0.95 as an example, the grinding temperature calibration test is carried out by using the same equipment, materials and process parameters as the machining process. The real-time temperature rise and tangential force of the workpiece are detected on the grinding side, so as to calculate the total grinding heat power. The grinding temperature rise coefficient is obtained by the quotient of the total grinding heat power, the tangential force and the grinding wheel speed. The average value is calculated after multiple tests with different parameters.

[0068] Real-time grinding thermal power refers to the heat introduced into the workpiece per unit time during the grinding process. The total thermal power is obtained by calculating the product of the real-time tangential grinding force and the real-time linear velocity of the grinding wheel by the processing terminal. The real-time grinding thermal power is then calculated by multiplying the total thermal power and the grinding temperature rise coefficient.

[0069] Step S302: Analyze the real-time grinding depth, real-time grinding width, and grinding wheel diameter to generate the real-time grinding area.

[0070] The real-time grinding area refers to the contact area between the grinding wheel and the workpiece. The contact arc length between the grinding wheel and the workpiece is obtained by calculating the square root of the product of the grinding wheel diameter and the real-time grinding depth by the processing terminal. Then, the real-time grinding area is obtained by calculating the product of the contact arc length and the real-time grinding width. By determining the real-time grinding area, area boundary data is provided for subsequent calculation of heat flux density.

[0071] Step S303: Calculate the quotient of real-time grinding heat power and real-time grinding area to generate the instantaneous heat flux density on the grinding side.

[0072] In this step, the instantaneous heat flux density on the grinding side is the same as that in step S202, and is obtained by the processing terminal by calculating the quotient of the real-time grinding heat power and the real-time grinding area.

[0073] Reference Figure 4 The steps for generating a grinding-side temperature sequence include calculating the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side based on a preset real-time grinding temperature model. Step S400: Based on the grinding heating model, calculate the instantaneous heat flux density on the grinding side, the thermal diffusivity of the workpiece, the thermal conductivity of the workpiece, the density of the workpiece, and the specific heat capacity of the workpiece to generate the temperature change on the grinding side.

[0074] Among them, the temperature change on the grinding side refers to the temperature rise on the grinding side, which is calculated by the processing terminal by substituting the instantaneous heat flux density on the grinding side, the thermal diffusivity of the workpiece, the thermal conductivity of the workpiece, the density of the workpiece, and the specific heat capacity of the workpiece into the grinding temperature rise model.

[0075] Step S401: Collect real-time workpiece temperature, real-time coolant temperature and real-time grinding machine temperature based on grinding side coordinates.

[0076] Among them, the real-time workpiece temperature refers to the workpiece temperature before the corresponding position of the grinding side coordinate is ground, which is obtained by a non-contact temperature sensor that detects the temperature of the grinding side coordinate and sends it to the processing terminal.

[0077] Real-time coolant temperature refers to the real-time temperature value of the coolant, which is detected by a temperature sensor installed in the coolant recovery loop and sent to the processing terminal.

[0078] Real-time grinding machine temperature refers to the temperature of the worktable used to fix the workpiece on the grinding machine. It is detected by a temperature sensor installed on the worktable and sent to the processing terminal.

[0079] By detecting real-time workpiece temperature, real-time coolant temperature, and real-time grinding machine temperature, data support is provided for subsequently determining the reference temperature on the grinding side.

[0080] Step S402: Calculate the real-time workpiece temperature, real-time coolant temperature, and real-time grinding machine temperature based on the reference temperature model to generate the grinding side reference temperature.

[0081] The grinding side reference temperature refers to the equilibrium temperature at the corresponding position of the grinding side coordinate before grinding. Before grinding, the workpiece temperature, coolant temperature and table temperature are in equilibrium. Therefore, the processing terminal substitutes the real-time workpiece temperature, real-time coolant temperature and real-time grinding machine temperature into the reference temperature model to calculate the grinding side reference temperature.

[0082] Step S403: Calculate the sum of the temperature change on the grinding side and the reference temperature on the grinding side to generate the real-time temperature on the grinding side.

[0083] Among them, the real-time temperature on the grinding side refers to the temperature at the corresponding position on the grinding side after grinding, which is obtained by the processing terminal by calculating the sum of the temperature change on the grinding side and the reference temperature on the grinding side.

[0084] Step S404: Integrate the real-time temperature of the grinding side based on the grinding side coordinates and the current time to generate a grinding side temperature sequence.

[0085] After determining the real-time temperature on the grinding side, the processing terminal establishes a correspondence between the current time, different grinding side coordinates, and the real-time temperature on the grinding side in the grinding side temperature sequence. This records the real-time temperature at different times and different grinding side positions, forming a grinding side temperature sequence, which provides data support for subsequent control of the non-grinding side temperature.

[0086] Reference Figure 5The steps for generating non-grinding side temperature control parameters by performing temperature mirror mapping based on the grinding side temperature sequence include: Step S500: Determine the grinding side coordinates and current time based on the grinding side temperature sequence.

[0087] In this step, the grinding side coordinates and current time are consistent with those in step S200, and are obtained by the processing terminal by calling the latest position and time data in the grinding side temperature sequence.

[0088] Step S501: Perform coordinate transformation based on the grinding side coordinates to generate the non-grinding side coordinates.

[0089] Among them, the non-grinding side coordinate refers to the position for temperature control on the non-grinding side of the workpiece. The non-grinding side coordinate is symmetrical with the center plane of the workpiece as the symmetric reference plane. The coordinates of the non-grinding side coordinate in the two-dimensional plane are consistent with the grinding side coordinate, except that the workpiece thickness is added or subtracted in the thickness direction.

[0090] Step S502: Collect the thermal conduction hysteresis time.

[0091] The thermal hysteresis time refers to the time it takes for the temperature on the grinding side of the workpiece to be conducted to the non-grinding side. It reflects the time difference between the temperature changes on the grinding and non-grinding sides, ensuring the synchronization of the temperatures on the grinding and non-grinding sides. Specific data acquisition methods are detailed in [reference needed]. Figure 6 The steps.

[0092] Step S503: Based on the grinding side coordinates, thermal hysteresis time, and current time, search in the grinding side temperature sequence to determine the real-time temperature of the non-grinding side.

[0093] The real-time temperature on the non-grinding side refers to the real-time temperature at the non-grinding side coordinates. This temperature is used to achieve temperature symmetry between the grinding and non-grinding sides of the workpiece, thereby eliminating the temperature gradient. It is obtained by the processing terminal from the grinding side temperature sequence based on the grinding side coordinates, thermal hysteresis time, and the current time. For specific methods, please refer to [reference needed]. Figure 7 The steps.

[0094] Step S504: Associate the non-grinding side coordinates and the real-time temperature of the non-grinding side to generate non-grinding side temperature control parameters.

[0095] In this step, the temperature control parameters of the non-grinding side are the same as those of the non-grinding side in step S102. The processing terminal associates the coordinates of the non-grinding side with the corresponding real-time temperature of the non-grinding side according to the data order to form temperature data with coordinates.

[0096] Reference Figure 6 The steps for collecting thermal conduction hysteresis time include: Step S600: Determine the thermal diffusivity and thickness of the workpiece based on its basic parameters.

[0097] In this step, the workpiece thermal diffusivity and workpiece thickness are the same as those in step S100. They are obtained by the processing terminal from the workpiece basic parameters according to the usage requirements. The workpiece thermal diffusivity and workpiece thickness determine the time it takes for the workpiece temperature to be conducted from the grinding side to the non-grinding side.

[0098] Step S601: Calculate the thermal diffusivity and thickness of the workpiece based on the preset thermal conduction hysteresis model to generate the thermal conduction hysteresis time.

[0099] The thermal conduction hysteresis model is used to calculate the time it takes for workpiece temperature to be conducted from one side to the corresponding other side. The specific expression is as follows: .

[0100] In the formula, For heat conduction hysteresis time, For workpiece thickness, This represents the thermal diffusivity of the workpiece.

[0101] The model is based on a one-dimensional unsteady-state heat conduction equation, reflecting the relationship between workpiece thickness and thermal diffusivity and heat transfer time. That is, the thicker the workpiece, the longer the heat transfer time, and the greater the thermal diffusivity, the shorter the heat transfer time.

[0102] The thermal conduction hysteresis time in this step is the same as that in step S502, and is calculated by the processing terminal by substituting the workpiece thermal diffusivity and workpiece thickness into the thermal conduction hysteresis model.

[0103] Reference Figure 7 The steps for determining the real-time temperature of the non-grinding side by searching the grinding side temperature sequence based on the grinding side coordinates, thermal hysteresis time, and current time include: Step S700: Calculate the difference between the current time and the thermal hysteresis time to generate the thermal compensation time.

[0104] Among them, the thermal conduction compensation time refers to the time required to match the temperature of the non-grinding side to the temperature of the grinding side in advance in order to offset the lag effect of heat conduction. It is obtained by the processing terminal calculating the difference between the current time and the thermal conduction lag time. By determining the thermal conduction compensation time, the problem of misalignment of the conduction time of the grinding side temperature and the non-grinding side temperature in the workpiece can be solved.

[0105] Step S701: Based on the grinding side coordinates and thermal compensation time, search in the grinding side temperature sequence to determine the ideal non-grinding side temperature.

[0106] The ideal non-grinding side temperature refers to the temperature at which the non-grinding side is controlled without considering heat dissipation. The processing terminal finds the real-time temperature of the grinding side corresponding to the grinding side coordinate in the grinding side temperature sequence based on the heat conduction compensation time, and defines the real-time temperature of the grinding side as the ideal non-grinding side temperature.

[0107] Step S702: Determine the heat dissipation compensation coefficient based on the non-grinding side coordinates.

[0108] The heat dissipation compensation coefficient refers to the compensation coefficient for heat loss at the corresponding position on the non-grinding side coordinate. It is obtained by the processing terminal based on the analysis of the non-grinding side coordinate. The specific method is described in [reference needed]. Figure 8 The process involves using a heat dissipation compensation coefficient to compensate for the temperature loss on the non-grinding side, ensuring that the temperatures on the grinding side and the non-grinding side are symmetrical.

[0109] Step S703: Calculate the product of the heat dissipation compensation coefficient and the ideal non-grinding side temperature to generate the real-time temperature of the non-grinding side.

[0110] In this step, the real-time temperature of the non-grinding side is the same as that of the non-grinding side in step S503, and is obtained by multiplying the heat dissipation compensation coefficient and the ideal non-grinding side temperature by the processing terminal.

[0111] Reference Figure 8 The steps for determining the heat dissipation compensation coefficient based on the non-grinding side coordinates include: Step S800: Determine the coordinate edge distance based on the non-grinding side coordinates.

[0112] Among them, the coordinate edge distance refers to the minimum distance between the non-grinding side coordinate and the edge of the workpiece. The processing terminal calculates the distance from the non-grinding side coordinate to the four edges respectively based on the non-grinding side coordinate, and selects the minimum value as the coordinate edge distance. By determining the coordinate edge distance, the distance from the coordinate to the edge reflects the heat dissipation degree of the coordinate. The closer the distance, the more heat is dissipated.

[0113] Step S801: Calculate the distance to the coordinate edge based on the preset heat dissipation compensation model to generate the heat dissipation compensation coefficient.

[0114] The heat dissipation compensation model refers to the model used to calculate the compensation coefficient for the heat loss temperature of the non-grinding side coordinate. The specific expression is as follows: .

[0115] In the formula, This is the heat dissipation compensation coefficient. The preset compensation gain coefficient, Distance from the coordinate edge The preset center-edge distance.

[0116] The compensation gain coefficient refers to the intensity of the influence of the heat exchange degree between the workpiece and the environment on the temperature loss on the non-grinding side, and determines the degree of compensation for the temperature loss on the non-grinding side. It is obtained by heating the workpiece to a set temperature, collecting the temperature decay curves at different positions of the workpiece, and combining the heat loss temperature ratio at different positions of the workpiece with the least squares method for fitting.

[0117] The center-edge distance refers to the minimum distance from the center of the workpiece to its edge, serving as a benchmark value for quantifying the heat exchange intensity between the workpiece and the environment.

[0118] By calculating the difference between the reciprocal of the distance from the coordinate edge and the reciprocal of the distance from the center edge, the heat transfer intensity between the workpiece and the environment is quantified by the angle of the difference between the reciprocal distances. The larger the distance from the coordinate edge, the smaller the heat transfer intensity, and therefore the smaller the temperature loss. At this time, the heat dissipation compensation coefficient is smaller. When the distance from the coordinate edge is equal to the distance from the center edge, the heat dissipation intensity is the minimum, and no compensation is performed at this time.

[0119] The heat dissipation compensation coefficient in this step is the same as that in step S702, and is calculated by the processing terminal by substituting the coordinate edge distance into the heat dissipation compensation model.

[0120] Based on the same inventive concept, embodiments of this application provide a grinding machine precision control system, including: The data acquisition module is used to collect basic workpiece parameters, grinding machine processing parameters, grinding side coordinates, current time, real-time workpiece temperature, real-time coolant temperature, real-time grinding machine temperature, and thermal conduction hysteresis time. A memory used to store a program for a grinding machine precision control method; The processor is a program in memory that can be loaded and executed by the processor to implement a grinding machine precision control method.

[0121] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device, and unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0122] This application provides a computer-readable storage medium storing a computer program that can be loaded by a processor and executed as a grinding machine precision control method.

[0123] Computer storage media include, for example, USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, optical disks, and other media that can store program code.

[0124] Based on the same inventive concept, embodiments of this application provide a smart terminal, including a memory and a processor, wherein the memory stores a computer program that can be loaded and executed by the processor to perform a grinding machine precision control method.

[0125] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional modules is used as an example. In practical applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above. The specific working process of the system, device, and unit described above can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0126] The above are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Any feature disclosed in this specification (including the abstract and drawings) may be replaced by other equivalent or similar features unless specifically stated otherwise. That is, unless specifically stated otherwise, each feature is only one example of a series of equivalent or similar features.

Claims

1. A method for controlling the precision of a grinding machine, characterized in that, include: Collect basic workpiece parameters and grinding machine machining parameters; The temperature of the pre-set grinding side is quantified based on the workpiece's basic parameters and the grinding machine's processing parameters to generate a grinding side temperature sequence. Temperature mirror mapping is performed based on the temperature sequence on the grinding side to generate temperature control parameters on the non-grinding side. The workpiece temperature is controlled by a preset temperature control unit based on the temperature control parameters of the non-grinding side, so as to achieve temperature symmetry between the grinding side and the non-grinding side of the workpiece.

2. The grinding machine precision control method according to claim 1, characterized in that, The steps for quantifying the preset grinding side temperature based on workpiece basic parameters and grinding machine processing parameters to generate a grinding side temperature sequence include: Collect the grinding side coordinates and the current time; The grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed, and grinding wheel diameter are determined based on the grinding side coordinates, current time, and grinding machine processing parameters. The grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear speed and grinding wheel diameter are analyzed to generate the instantaneous heat flux density on the grinding side. The workpiece's thermal diffusivity, thermal conductivity, density, and specific heat capacity are determined based on its basic parameters. Based on a preset real-time grinding temperature model, the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side are calculated to generate a grinding side temperature sequence.

3. The grinding machine precision control method according to claim 2, characterized in that, The steps for generating the instantaneous heat flux density on the grinding side include analyzing the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, real-time grinding wheel linear velocity, and grinding wheel diameter. Based on the preset grinding force model, the grinding specific energy coefficient, real-time grinding depth, real-time grinding width, real-time workpiece speed, and real-time grinding wheel linear speed are calculated to generate real-time tangential grinding force. The product of real-time tangential grinding force, real-time linear velocity of the grinding wheel, and preset grinding temperature rise coefficient is calculated to generate real-time grinding heat power. The real-time grinding depth, real-time grinding width, and grinding wheel diameter are analyzed to generate the real-time grinding area; Calculate the quotient of real-time grinding heat power and real-time grinding area to generate the instantaneous heat flux density on the grinding side; The expression for the grinding force model is: ， In the formula, For real-time tangential grinding force, For grinding specific energy coefficient, For real-time grinding depth, For real-time grinding width, For the real-time speed of the workpiece, This represents the real-time linear velocity of the grinding wheel.

4. The grinding machine precision control method according to claim 2, characterized in that, The grinding real-time temperature model includes a grinding heating model and a reference temperature model. The steps for generating the grinding side temperature sequence based on the preset grinding real-time temperature model include calculating the instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side. The instantaneous heat flux density, workpiece thermal diffusivity, workpiece thermal conductivity, workpiece density, and workpiece specific heat capacity on the grinding side are calculated based on the grinding temperature rise model to generate the temperature change on the grinding side. Real-time workpiece temperature, real-time coolant temperature, and real-time grinding machine temperature are collected based on grinding side coordinates. The real-time workpiece temperature, real-time coolant temperature, and real-time grinding machine temperature are calculated based on the reference temperature model to generate the grinding side reference temperature. The sum of the temperature change on the grinding side and the reference temperature on the grinding side is calculated to generate the real-time temperature on the grinding side. The grinding side temperature sequence is generated by integrating the grinding side coordinates and the current time with the real-time grinding side temperature.

5. The grinding machine precision control method according to claim 1, characterized in that, The steps for generating non-grinding side temperature control parameters by performing temperature mirror mapping based on the grinding side temperature sequence include: Determine the grinding side coordinates and current time based on the grinding side temperature sequence; Coordinate transformation is performed based on the grinding side coordinates to generate the non-grinding side coordinates; Collect the thermal conduction hysteresis time; The real-time temperature of the non-grinding side is determined by searching the temperature sequence on the grinding side based on the grinding side coordinates, thermal hysteresis time, and current time. Correlate the non-grinding side coordinates and the real-time temperature of the non-grinding side to generate non-grinding side temperature control parameters.

6. The grinding machine precision control method according to claim 5, characterized in that, The steps for collecting thermal conduction hysteresis time include: Determine the thermal diffusivity and thickness of the workpiece based on its basic parameters. The thermal diffusivity and thickness of the workpiece are calculated based on a preset thermal conduction hysteresis model to generate the thermal conduction hysteresis time. The expression for the thermal conduction hysteresis model is: ， In the formula, For heat conduction hysteresis time, For workpiece thickness, This represents the thermal diffusivity of the workpiece.

7. A grinding machine precision control method according to claim 5, characterized in that, The steps for determining the real-time temperature of the non-grinding side by searching the grinding side temperature sequence based on the grinding side coordinates, thermal hysteresis time, and current time include: Calculate the difference between the current time and the thermal hysteresis time to generate the thermal compensation time; The ideal non-grinding side temperature is determined by searching the grinding side temperature sequence based on the grinding side coordinates and thermal compensation time. Determine the heat dissipation compensation coefficient based on the non-grinding side coordinates; Calculate the product of the heat dissipation compensation coefficient and the ideal non-grinding side temperature to generate the real-time temperature of the non-grinding side.

8. A grinding machine precision control method according to claim 7, characterized in that, The steps for determining the heat dissipation compensation coefficient based on the non-grinding side coordinates include: Determine the coordinate edge distance based on the non-grinding side coordinates; The distance to the coordinate edge is calculated based on the preset heat dissipation compensation model to generate the heat dissipation compensation coefficient. The expression for the heat dissipation compensation model is: ， In the formula, For heat dissipation compensation coefficient, For the preset compensation gain coefficient, Distance to coordinate edge The preset center-edge distance.

9. A precision control system for a grinding machine, characterized in that, include: The data acquisition module is used to acquire basic workpiece parameters and grinding machine processing parameters; A memory for storing a program for a grinding machine precision control method as described in any one of claims 1 to 8; The processor and the program in the memory can be loaded and executed by the processor to implement the grinding machine precision control method as described in any one of claims 1 to 8.

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