Tool Changer Control System and Method Based on Variable Frequency Speed ​​Regulation

Abstract

This application provides a tool changer control system and method based on variable frequency speed regulation, belonging to the field of tool changer control technology. The system includes: acquiring tool change commands and tool information, identifying the machining stage, collecting tool arm load information, querying and calculating real-time parameters and historical tool data, calculating the tool magazine circumferential load vector, and determining and prompting for load thresholds. By combining the speed curve planning module with the operating frequency output by the frequency converter, the system achieves staged and precise adjustment of the tool arm motor speed, avoiding problems such as structural impact, accelerated wear, and decreased tool change accuracy caused by coarse speed control in traditional tool changing processes. This extends the equipment's service life and improves tool changer stability.

Description

Technical Field

[0001] This invention relates to the field of tool changer control technology. Specifically, it relates to a tool changer control system and method based on variable frequency speed regulation. Background Technology

[0002] As CNC machining equipment develops towards higher speeds and greater flexibility, tool changer systems have become a key component in improving machine tool automation and machining efficiency. Tool changer control systems work in conjunction with the drive arm motor and the tool magazine motor to complete the tool grabbing and changing actions, and are widely used in precision machining and continuous machining scenarios. In order to adapt to changes in different tool weights, machining rhythms, and complex working conditions, control technologies such as servo control, position detection, and intelligent judgment have been gradually introduced in recent years in an attempt to improve the reliability of tool changing actions and the stability of system operation. However, most existing tool changing control schemes are still based on fixed speed control logic, lacking further breakthroughs in the ability to finely adjust under dynamic operating conditions.

[0003] Firstly, in tool changing systems lacking variable frequency speed control mechanisms, the tool arm motor is prone to inertial impact under high speed or high load conditions. It cannot dynamically plan the operating speed according to the tool quality and indexing angle, resulting in increased equipment vibration, higher energy consumption, and accumulation of mechanical fatigue, making it difficult to balance efficiency and stability.

[0004] Secondly, conventional tool magazine control methods generally do not incorporate a tool magazine circumferential load analysis mechanism. They cannot identify and compensate for the rotational off-center load caused by the weight of tools at different workstations. This can easily lead to the accumulation of tool changing errors during long-term operation, causing problems such as tool arm position deviation and clamping instability, which affect the overall tool changing accuracy and system lifespan. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a tool changer control system and method based on variable frequency speed regulation. The aim is to dynamically adjust the tool changer trajectory and operating frequency by constructing a tool magazine circumferential load vector determination module and a speed curve planning module, integrating a tool arm motor operating frequency control and a tool magazine load distribution adaptive judgment mechanism. This significantly improves the operational stability and structural coordination of the tool changer process, effectively solves the problems of inertial impact and indexing deviation, and enhances the system's tool changer control accuracy and long-term operational stability under various working conditions.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] The tool changer control system and method based on variable frequency speed regulation includes the following steps:

[0008] Step S100: Obtain tool change command and tool information, identify the machining stage, collect tool arm load information, query and calculate real-time parameters and tool historical data, calculate tool magazine circumferential load vector, and determine and prompt the load threshold.

[0009] Step S200: Generate speed curves for the tool magazine motor and the tool arm motor based on the mechanical load data, and make corrections and adjustments. Set the synchronous operation parameters of the tool arm motor based on the speed curve of the tool magazine motor.

[0010] Step S300: Based on the speed curve, control the frequency converter to start the tool magazine motor and the tool arm motor, adjust the operating frequency, monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation of vector control based on the current and torque data, and handle abnormal operating conditions.

[0011] Step S400: Deploy a rotary encoder or photoelectric sensor and obtain the rotation angle value of the tool magazine motor. Calculate the rotation angle difference between the target tool and the tool magazine motor based on the rotation angle value of the tool magazine motor, determine the deceleration trigger point and execute segmented deceleration control, and perform micro-jitter compensation based on the rotation angle difference.

[0012] Step S500: Drive the tool arm motor to perform the tool picking action based on the speed curve, deploy the flexible compensation mechanism, and perform the floating tool locking operation. Dynamically adjust the speed and torque during the clamping process according to the quality information, and determine the completion and locking of the tool changing action based on the flexible compensation mechanism.

[0013] Step S600: Based on the tool arm motor drive module, control the tool arm motor to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup. Update the overall mass and total load data of the tool magazine and the circumferential load vector of the tool magazine based on the tool parameter database. Perform automatic rearrangement of tool positions and load balancing based on the circumferential load vector of the tool magazine, generate tool change completion status information, and output the current status data of the tool magazine.

[0014] As a preferred embodiment of the present invention, step S100 specifically comprises:

[0015] Step S100.1: Obtain tool change instructions and tool information, and identify the machining stage.

[0016] Upon receiving the tool change control command from the upper-level CNC control system, the tool information acquisition module is activated through the tool magazine tool change control system to acquire the tool change control command.

[0017] The tool magazine tool changing control system includes: an upper-level numerical control control system, a tool information acquisition module, a process stage identification module, a tool arm current detection module, a tool parameter database, a tool load analysis module, a speed curve planning module, a tool magazine motor drive module, a tool arm motor drive module, a self-learning optimization algorithm module, a motor drive status detection module, and a tool magazine structure vibration detection module.

[0018] The tool change control command includes: the number, quality, and outer diameter information of the tool currently mounted on the spindle and the next target tool to be changed, the position information of the current tool on the spindle, and the tool position information of the target tool in the tool magazine.

[0019] The process stage identification module obtains the processing stage label information from the upper CNC control system, including the roughing stage and the finishing stage.

[0020] When the current machining stage is identified as the finishing stage, the machining stability priority mode will be set. When it is identified as the roughing stage, the tool changer control system will be allowed to use a higher speed tool change mode.

[0021] Step S100.2: Collect tool arm load information, query and calculate real-time parameters and tool historical data, calculate tool magazine circumferential load vector, and determine and prompt the load threshold.

[0022] Based on the acquired processing stage label information, load sensors deployed at the load feedback points of the cutter arm drive structure are used to collect mechanical load data of the cutter arm in real time.

[0023] By using the tool parameter database, historical usage records, static quality information, and dynamic load distribution data of the tool are extracted based on the current spindle tool number and the next target tool to be replaced.

[0024] The mass information of each tool in the tool magazine is queried in turn, and the mass information of all tools in the tool magazine is accumulated and calculated through the tool load analysis module to obtain the total mass load data of the tool magazine.

[0025] The tool load analysis module further determines the tool magazine circumferential load vector based on the specific distribution angle of each tool in the tool magazine on the tool magazine circumferential structure and through the circumferential off-center load calculation algorithm.

[0026] The direction and intensity of the overall load of the tool magazine in the circumferential direction are determined by the circumferential load vector. The larger the value of the circumferential load vector, the higher the degree of unevenness in the overall load distribution of the tool magazine.

[0027] The tool load analysis module compares the currently calculated total load data of the tool magazine with the preset tool magazine load threshold. When the total load of the tool magazine exceeds the preset tool magazine load threshold of 45 kg, an overload warning message is immediately issued. When the magnitude of the tool magazine circumferential off-center load vector exceeds the set off-center load balance threshold of 3.5 kg·m, an off-center load warning message is triggered.

[0028] As a preferred embodiment of the present invention, step S200 specifically comprises:

[0029] Step S200.1: Generate speed curves for the tool magazine motor and the tool arm motor based on mechanical load data.

[0030] Step S200.2: Correct and adjust the speed curve based on the label information of the processing stage.

[0031] Step S200.3: Set the synchronous operation parameters of the tool arm motor based on the speed curve of the tool magazine motor.

[0032] Before the current spindle tool completes machining and enters the tool change preparation stage, the tool arm motor remains in a waiting and locked state. After the tool magazine motor completes the rotational positioning action of the target tool, the tool arm motor is started through the speed curve planning module and the tool magazine motor status feedback to perform the tool retrieval operation.

[0033] As a preferred embodiment of the present invention, step S300 specifically comprises:

[0034] Step S300.1: Based on the speed curve, control the frequency converter to start the tool magazine motor and the tool arm motor, and adjust the operating frequency.

[0035] The speed curves of the tool magazine motor and the tool arm motor are generated and cached in the high-speed cache register by the speed curve planning module. Start commands are sent to the frequency converters in the tool magazine motor drive module and the tool arm motor drive module. After receiving the start commands, the tool magazine motor drive module and the tool arm motor drive module output low start frequency control signals to the tool magazine motor and the tool arm motor through the frequency converters.

[0036] The initial value of the low start-up frequency control signal is set to be in the range of 5 Hz to 10 Hz. The specific selection of the initial value of the start-up frequency is determined based on the total weight data of the tool magazine: when the total weight data of the tool magazine exceeds 30 kg, the initial value of the start-up frequency is 5 Hz; when the total weight data of the tool magazine is less than or equal to 30 kg, the initial value of the start-up frequency is 10 Hz.

[0037] After the tool magazine motor and the tool arm motor complete the soft start and enter the acceleration zone, the output operating frequency of the tool magazine motor and the tool arm motor is gradually increased according to the multi-segment acceleration and deceleration curves planned by the speed curve planning module.

[0038] Step S300.2: Monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation for vector control based on the current and torque data, and handle abnormal operating conditions.

[0039] During the gradual increase in frequency, the current and torque sensors integrated in the tool magazine motor drive module and the tool arm motor drive module collect the actual operating current data and real-time torque data of the tool magazine motor and the tool arm motor in real time at a frequency of 50 milliseconds.

[0040] The current sensor and torque sensor are respectively installed inside the tool magazine motor drive module and the tool arm motor drive module.

[0041] The vector control torque automatic compensation algorithm analyzes the actual operating current data and real-time torque data of the tool magazine motor and the tool arm motor in real time. It compares the actual operating current data and real-time torque data with the standard operating data planned by the speed curve planning module and calculates the real-time torque compensation value.

[0042] If the real-time torque data of the tool magazine motor or the cutter arm motor is lower than 90% of the planned standard operating data during the acceleration phase, the inverter output power will be automatically increased to increase the torque output of the tool magazine motor or the cutter arm motor. If the real-time torque data exceeds 110% of the planned standard operating data, the inverter output power will be automatically reduced.

[0043] During the multi-stage variable frequency soft start and step-by-step acceleration process, the operating frequency deviation and real-time load change of the tool magazine motor and the tool arm motor are monitored in real time, and abnormal state threshold parameters are set: when the operating frequency deviation of the tool magazine motor exceeds ±5 Hz, or the real-time load change of the tool arm motor exceeds ±0.4 kg, the speed curve correction interruption mechanism is immediately activated.

[0044] After the speed curve correction interruption mechanism is started, the operating frequency is gradually reduced by controlling the tool magazine motor and the tool arm motor with an abnormal speed reduction strategy of reducing the frequency by 5 Hz in each segment, until the abnormal state is completely eliminated.

[0045] Once the abnormal condition is completely eliminated, the acceleration process will be restarted at a reduced frequency until the operating status of the tool magazine motor and the tool arm motor is fully matched with the planned speed curve, and then the subsequent tool changing action will continue.

[0046] As a preferred embodiment of the present invention, step S400 specifically includes:

[0047] Step S400.1: Deploy a rotary encoder or photoelectric sensor and obtain the rotation angle value of the tool magazine motor.

[0048] Step S400.2: Calculate the difference in rotation angle between the target tool and the tool magazine motor based on the rotation angle value of the tool magazine motor, and determine the deceleration trigger point and execute segmented deceleration control.

[0049] Step S400.3: Perform micro-jitter compensation based on the rotation angle difference.

[0050] When the difference in rotation angle is less than 2°, the tool magazine motor enters the micro-jitter compensation control stage. The frequency converter reduces the output frequency of the tool magazine motor to below 2 Hz, and the tool magazine motor rotates slightly in both directions by alternately outputting low-frequency pulse signals in both directions.

[0051] When the rotation angle difference of the tool magazine motor is stable within ±0.3° and remains stable for more than 150 milliseconds, the tool magazine changing control system determines that the tool magazine motor has been accurately positioned to the preset angle coordinate position of the target tool, locks the position of the tool magazine motor, and sends a tool pick-up preparation command to the tool arm motor drive module.

[0052] As a preferred embodiment of the present invention, step S500 specifically comprises:

[0053] Step S500.1: Drive the tool arm motor to perform the tool picking action based on the speed curve, deploy the flexible compensation mechanism, and perform the floating tool holding operation.

[0054] Step S500.2: Dynamically adjust the speed and torque during the clamping process based on the quality information and outer diameter information, and determine the completion and locking of the tool changing action based on the flexible compensation mechanism.

[0055] The tool magazine changing control system calls the tool parameter database to obtain the target tool's mass information and outer diameter information, and inputs the target tool's mass information and outer diameter information into the speed curve planning module. The speed curve planning module dynamically adjusts the clamping speed and torque of the tool arm motor based on the target tool's mass information and outer diameter information.

[0056] During the tool gripping process, the tool arm gripping axis moves slowly and at a constant speed when approaching the tool cup and when performing the tool-locking action. As the tool arm gripping axis moves away from the tool cup and toward the spindle, the speed gradually increases to the maximum allowable operating speed.

[0057] When the axial float of the tool arm gripping axis is less than ±0.3 mm and the float remains stable for more than 150 milliseconds, the tool magazine changing control system determines that the tool gripping action of the tool arm gripping axis has been completed.

[0058] After determining that the tool arm gripping shaft has completed its tool-grabbing action, the tool magazine changing control system will immediately control the tool arm motor to enter the locking stage. The locking control circuit in the tool arm motor drive module will trigger the locking pin mechanism to enter the side groove of the tool arm gripping shaft.

[0059] As a preferred embodiment of the present invention, step S600 specifically comprises:

[0060] Step S600.1: Based on the tool arm motor drive module, control the tool arm motor to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup.

[0061] Step S600.2: Update the overall mass and total load data of the tool magazine and the circumferential off-center load vector of the tool magazine based on the tool parameter database.

[0062] Step S600.3: Based on the tool magazine circumferential off-center load vector, perform automatic tool position rearrangement and off-center load balancing, generate tool change completion status information, and output the current status data of the tool magazine.

[0063] When the magnitude of the tool magazine circumferential off-center load vector exceeds 3.5 kg·m, the tool position rearrangement strategy will be automatically activated.

[0064] Based on the tool parameter database, heavy tools with a mass exceeding 1.8 kg were identified and marked as requiring tool rearrangement.

[0065] By analyzing the distribution of empty tool cups in the tool magazine's circumferential structure, a tool position rearrangement optimization algorithm is invoked to determine multiple tool position rearrangement paths. Based on the analysis of multiple tool position rearrangement paths, the tool position rearrangement path with the lowest magnitude of the tool magazine's circumferential off-center load vector is selected as the execution strategy. According to the selected tool position rearrangement path, the tool arm motor is driven by the tool arm motor drive module to gradually perform the heavy tool repositioning operation.

[0066] Prioritize moving heavy tools marked as needing rearrangement to symmetrical or relatively balanced positions on the tool magazine's circumferential structure, with the goal of reducing the circumferential load vector magnitude of the tool magazine to below 2.0 kg·m.

[0067] After each reordering operation of a single tool position is completed, the tool parameter database is updated again, and the tool load analysis module is called again to calculate the total load data of the tool magazine and the tool magazine circumferential load vector. The reordering operation will stop when the magnitude of the tool magazine circumferential load vector meets the target threshold of no more than 2.0 kg·m or there are no more feasible tool position reordering paths.

[0068] After completing the actions of loading the target tool into the spindle interface, returning the old tool to the tool cup position, updating the tool data, and rearranging the tool position, the current status of the tool magazine is marked as tool change complete.

[0069] When the tool change is complete, the data of the current tool change action will be automatically recorded.

[0070] The tool changer control system based on variable frequency speed regulation specifically includes the following modules:

[0071] The tool change control deployment module is used to acquire tool change commands and tool information, identify the machining stage, collect tool arm load information, query and calculate real-time parameters and historical tool data, calculate the tool magazine circumferential load vector, and determine and prompt the load threshold.

[0072] The machining identification task module is used to generate speed curves for the tool magazine motor and the tool arm motor based on mechanical load data, and to make corrections and adjustments. Based on the speed curve of the tool magazine motor, the synchronous operation parameters of the tool arm motor are set.

[0073] The load acquisition and judgment module is used to control the inverter to start the tool magazine motor and the tool arm motor based on the speed curve, adjust the operating frequency, monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation of vector control based on the current and torque data, and handle abnormal operating conditions.

[0074] The variable frequency control module is designed to deploy rotary encoders or photoelectric sensors to obtain the rotation angle value of the tool magazine motor. Based on the rotation angle value of the tool magazine motor, the rotation angle difference between the target tool and the tool magazine motor is calculated, the deceleration trigger point is determined, and segmented deceleration control is executed. Micro-amplitude jitter compensation is performed based on the rotation angle difference.

[0075] The clamping adjustment and correction module is used to drive the tool arm motor to perform the tool picking action based on the speed curve, deploy a flexible compensation mechanism, and perform a floating tool locking operation. It dynamically adjusts the speed and torque during the clamping process based on quality information, and determines the completion and locking of the tool changing action based on the flexible compensation mechanism.

[0076] The tool change data update module is used to control the tool arm motor to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup based on the tool arm motor drive module. It updates the overall mass and total load data of the tool magazine and the tool magazine circumferential load vector based on the tool parameter database. Based on the tool magazine circumferential load vector, it performs automatic tool position rearrangement and load balancing, generates tool change completion status information, and outputs the current status data of the tool magazine.

[0077] Compared with the prior art, the beneficial effects of the present invention are:

[0078] 1. By combining the speed curve planning module with the operating frequency output by the frequency converter, the speed of the cutter arm motor can be precisely adjusted in stages. This avoids problems such as structural impact, increased wear, and decreased tool changing accuracy caused by coarse speed control in traditional tool changing processes, thereby extending the service life of the equipment and improving tool changing stability.

[0079] 2. The tool magazine's circumferential off-center load vector is used to determine the current tool arm load distribution in real time, and the speed is corrected based on the angle difference judgment strategy. This makes the tool changing control process more flexible and adjustable, effectively dealing with dynamic load changes caused by different tool weights, uneven positions, or non-standard tools, so that the tool changing rhythm is not disturbed by off-center load.

[0080] 3. By using a floating compensation structure in conjunction with a clamping action adjustment module, the angle difference and positioning error are finely corrected at the end of the tool change, effectively overcoming the misalignment problem caused by the accumulation of mechanical errors in the tool holder, tool arm and frequency conversion drive system, improving the consistency and reliability of tool insertion and removal, and reducing the number of manual interventions.

[0081] 4. After the tool change is completed, the system can update the tool status information and tool position number information in the tool magazine tool change control system in real time based on the clamping action completion signal and the floating compensation completion status signal. This provides accurate basic tool data for subsequent machining task scheduling, reduces manual data entry, and improves the intelligence and response efficiency of the CNC system. Attached Figure Description

[0082] Figure 1 A flowchart of a tool changer control method based on variable frequency speed regulation provided for the invention.

[0083] Figure 2 A framework diagram of a tool changer control system based on variable frequency speed regulation provided for the invention. Detailed Implementation

[0084] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0085] Please see Figure 1 , Figure 1 A flowchart of a tool changer control method based on variable frequency speed regulation is provided for embodiments of this application.

[0086] In this embodiment, the tool changer control system and method based on variable frequency speed regulation may include steps S100, S200, S300, S400, S500 and S600.

[0087] Step S100: Obtain tool change command and tool information, identify the machining stage, collect tool arm load information, query and calculate real-time parameters and tool historical data, calculate tool magazine circumferential load vector, and determine and prompt the load threshold.

[0088] Step S200: Generate speed curves for the tool magazine motor and the tool arm motor based on the mechanical load data, and make corrections and adjustments. Set the synchronous operation parameters of the tool arm motor based on the speed curve of the tool magazine motor.

[0089] Step S300: Based on the speed curve, control the frequency converter to start the tool magazine motor and the tool arm motor, adjust the operating frequency, monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation of vector control based on the current and torque data, and handle abnormal operating conditions.

[0090] Step S400: Deploy a rotary encoder or photoelectric sensor and obtain the rotation angle value of the tool magazine motor. Calculate the rotation angle difference between the target tool and the tool magazine motor based on the rotation angle value of the tool magazine motor, determine the deceleration trigger point and execute segmented deceleration control, and perform micro-jitter compensation based on the rotation angle difference.

[0091] Step S500: Drive the tool arm motor to perform the tool picking action based on the speed curve, deploy the flexible compensation mechanism, and perform the floating tool locking operation. Dynamically adjust the speed and torque during the clamping process according to the quality information, and determine the completion and locking of the tool changing action based on the flexible compensation mechanism.

[0092] Step S600: Based on the tool arm motor drive module, control the tool arm motor to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup. Update the overall mass and total load data of the tool magazine and the circumferential load vector of the tool magazine based on the tool parameter database. Perform automatic rearrangement of tool positions and load balancing based on the circumferential load vector of the tool magazine, generate tool change completion status information, and output the current status data of the tool magazine.

[0093] In some specific embodiments, step S100 specifically includes:

[0094] Step S100.1: Obtain tool change instructions and tool information, and identify the machining stage.

[0095] Upon receiving the tool change control command from the upper-level CNC control system, the tool information acquisition module is activated through the tool magazine tool change control system to acquire the tool change control command.

[0096] The tool magazine tool changing control system includes: an upper-level numerical control control system, a tool information acquisition module, a process stage identification module, a tool arm current detection module, a tool parameter database, a tool load analysis module, a speed curve planning module, a tool magazine motor drive module, a tool arm motor drive module, a self-learning optimization algorithm module, a motor drive status detection module, and a tool magazine structure vibration detection module.

[0097] The tool change control command includes: the number, quality, and outer diameter information of the tool currently mounted on the spindle and the next target tool to be changed, the position information of the current tool on the spindle, and the tool position information of the target tool in the tool magazine.

[0098] The process stage identification module obtains the processing stage label information from the upper CNC control system, including the roughing stage and the finishing stage.

[0099] When the current machining stage is identified as the finishing stage, the machining stability priority mode will be set. When it is identified as the roughing stage, a higher speed tool change mode will be allowed.

[0100] Step S100.2: Collect tool arm load information, query and calculate real-time parameters and tool historical data, calculate tool magazine circumferential load vector, and determine and prompt the load threshold.

[0101] Based on the acquired processing stage label information, load sensors deployed at the load feedback points of the cutter arm drive structure are used to collect mechanical load data of the cutter arm in real time.

[0102] When no load sensor is installed on the cutter arm transmission structure, the current data of the cutter arm drive motor is detected in real time by the cutter arm current detection module, and the real-time current data is converted into the real-time load data currently borne by the cutter arm through the cutter arm current load calculation algorithm.

[0103] By using the tool parameter database, historical usage records, static quality information, and dynamic load distribution data of the tool are extracted based on the current spindle tool number and the next target tool to be replaced.

[0104] The mass information of each tool in the tool magazine is queried in turn, and the mass information of all tools in the tool magazine is accumulated and calculated through the tool load analysis module to obtain the total mass load data of the tool magazine.

[0105] The tool load analysis module further determines the tool magazine circumferential load vector based on the specific distribution angle of each tool in the tool magazine on the tool magazine circumferential structure and through the circumferential off-center load calculation algorithm.

[0106] The direction and intensity of the overall load of the tool magazine in the circumferential direction are determined by the circumferential load vector. The larger the value of the circumferential load vector, the higher the degree of unevenness in the overall load distribution of the tool magazine.

[0107] The tool load analysis module compares the currently calculated total load data of the tool magazine with the preset tool magazine load threshold. When the total load of the tool magazine exceeds the preset tool magazine load threshold of 45 kg, an overload warning message is immediately issued. When the magnitude of the tool magazine circumferential off-center load vector exceeds the set off-center load balance threshold of 3.5 kg·m, an off-center load warning message is triggered.

[0108] In some specific embodiments, step S200 specifically includes:

[0109] Step S200.1: Generate speed curves for the tool magazine motor and the tool arm motor based on mechanical load data.

[0110] The speed curve planning module is invoked to generate multi-segment acceleration and deceleration curves for the tool magazine motor and the tool arm motor, based on the mass information, the total load data of the tool magazine, and the circumferential off-center load vector of the tool magazine as input conditions.

[0111] The multi-segment acceleration / deceleration curve includes five consecutive operating speed segments, which are: starting frequency segment, acceleration segment, constant speed segment, pre-deceleration segment, and braking segment.

[0112] The speed curve planning module determines the operating parameters of the tool magazine motor based on the overall mass and total load data of the tool magazine and the circumferential off-center load vector of the tool magazine. The operating parameters of the tool magazine motor include:

[0113] When the total weight of the tool magazine is less than 30 kg and the magnitude of the circumferential load vector of the tool magazine is less than 1.5 kg·m, the acceleration of the tool magazine motor is set to 0.8 m / s², and the maximum operating frequency of the tool magazine motor is set to 80 Hz.

[0114] When the total load of the tool magazine is between 30 kg and 45 kg or the circumferential load vector magnitude of the tool magazine is between 1.5 kg·m and 3.5 kg·m, the acceleration of the tool magazine motor is set to 0.5 m / s², and the maximum operating frequency of the tool magazine motor is set to 60 Hz.

[0115] When the total load of the tool magazine exceeds 45 kg or the circumferential load vector magnitude of the tool magazine exceeds 3.5 kg·m, the acceleration of the tool magazine motor is limited to 0.3 m / s², and the maximum operating frequency of the tool magazine motor is limited to 45 Hz. It will automatically enter the low-impact mode, and the frequency of the tool magazine tool changing rhythm will be limited to no more than 10 times per minute.

[0116] Step S200.2: Correct and adjust the speed curve based on the label information of the processing stage.

[0117] When the process stage identification module identifies the current processing stage label information as the roughing stage, it allows the tool magazine motor and the tool arm motor to operate according to the operating parameters of the tool magazine motor.

[0118] When the process stage identification module identifies the current processing stage label information as the finishing stage, the acceleration correction coefficient of the tool magazine motor and the tool arm motor is set to 0.5, and the maximum operating frequency of the tool magazine motor and the tool arm motor is corrected to 80% of the originally planned maximum operating frequency.

[0119] When in the finishing stage, the strategy of preparing tools in advance is prohibited. The tool change action of the tool magazine motor and tool arm motor should be executed only after the current finishing instruction is completed.

[0120] If the speed curve planning module plans the tool magazine motor acceleration to be 0.8 m / s² under standard conditions, then the actual tool magazine motor acceleration during the finishing stage is adjusted to 0.4 m / s². If the original planned operating frequency of the tool magazine motor is 80 Hz, then the actual operating frequency of the tool magazine motor during the finishing stage is limited to within 64 Hz.

[0121] Step S200.3: Set the synchronous operation parameters of the tool arm motor based on the speed curve of the tool magazine motor.

[0122] Before the current spindle tool completes machining and enters the tool change preparation stage, the tool arm motor remains in a waiting and locked state. After the tool magazine motor completes the rotational positioning action of the target tool, the tool arm motor is started through the speed curve planning module and the tool magazine motor status feedback to perform the tool retrieval operation.

[0123] If the target tool mass carried by the current tool arm motor exceeds 1.8 kg, or the distance between the current spindle position and the center of the tool magazine exceeds 450 mm, the acceleration of the tool arm motor will be reduced to 0.3 m / s².

[0124] If the speed deviation of the tool magazine motor exceeds ±5 Hz, or the change in tool arm load exceeds ±0.4 kg, the speed curve correction interruption mechanism will be triggered immediately.

[0125] In some specific embodiments, step S300 specifically includes:

[0126] Step S300.1: Based on the speed curve, control the frequency converter to start the tool magazine motor and the tool arm motor, and adjust the operating frequency.

[0127] The speed curves of the tool magazine motor and the tool arm motor are generated and cached in the high-speed cache register by the speed curve planning module. Start commands are sent to the frequency converters in the tool magazine motor drive module and the tool arm motor drive module. After receiving the start commands, the tool magazine motor drive module and the tool arm motor drive module output low start frequency control signals to the tool magazine motor and the tool arm motor through the frequency converters.

[0128] The initial value of the low start-up frequency control signal is set to be in the range of 5 Hz to 10 Hz. The specific selection of the initial value of the start-up frequency is determined based on the total weight data of the tool magazine: when the total weight data of the tool magazine exceeds 30 kg, the initial value of the start-up frequency is 5 Hz; when the total weight data of the tool magazine is less than or equal to 30 kg, the initial value of the start-up frequency is 10 Hz.

[0129] After the tool magazine motor and the tool arm motor complete the soft start and enter the acceleration zone, the output operating frequency of the tool magazine motor and the tool arm motor is gradually increased according to the multi-segment acceleration and deceleration curves planned by the speed curve planning module.

[0130] The tool changer control system gradually increases the operating frequency of the tool magazine motor and the tool arm motor in increments of 5 Hz to 10 Hz, with each increment lasting 100 to 200 milliseconds. When the target tool mass is greater than 1.8 kg or the total load of the tool magazine exceeds 45 kg, the frequency increment is set to 5 Hz with a increment of 200 milliseconds. When the target tool mass is less than or equal to 1.8 kg and the total load of the tool magazine is less than or equal to 45 kg, the frequency increment is set to 10 Hz with a increment of 100 milliseconds.

[0131] Step S300.2: Monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation for vector control based on the current and torque data, and handle abnormal operating conditions.

[0132] During the gradual increase in frequency, the current and torque sensors integrated in the tool magazine motor drive module and the tool arm motor drive module collect the actual operating current data and real-time torque data of the tool magazine motor and the tool arm motor in real time at a frequency of 50 milliseconds.

[0133] The current sensor and torque sensor are respectively installed inside the tool magazine motor drive module and the tool arm motor drive module.

[0134] The vector control torque automatic compensation algorithm analyzes the actual operating current data and real-time torque data of the tool magazine motor and the tool arm motor in real time. It compares the actual operating current data and real-time torque data with the standard operating data planned by the speed curve planning module and calculates the real-time torque compensation value.

[0135] If the real-time torque data of the tool magazine motor or the tool arm motor is lower than 90% of the planned standard operating data during the acceleration phase, the inverter output power will be automatically increased to increase the torque output of the tool magazine motor or the tool arm motor. If the real-time torque data exceeds 110% of the planned standard operating data, the inverter output power will be automatically reduced.

[0136] During the multi-stage variable frequency soft start and step-by-step acceleration process, the operating frequency deviation and real-time load change of the tool magazine motor and the tool arm motor are monitored in real time, and abnormal state threshold parameters are set: when the operating frequency deviation of the tool magazine motor exceeds ±5 Hz, or the real-time load change of the tool arm motor exceeds ±0.4 kg, the speed curve correction interruption mechanism is immediately activated.

[0137] After the speed curve correction interruption mechanism is started, the operating frequency is gradually reduced by controlling the tool magazine motor and the tool arm motor with an abnormal speed reduction strategy of reducing the frequency by 5 Hz in each segment, until the abnormal state is completely eliminated.

[0138] Once the abnormal condition is completely eliminated, the acceleration process will be restarted at a reduced frequency until the operating status of the tool magazine motor and the tool arm motor is fully matched with the planned speed curve, and then the subsequent tool changing action will continue.

[0139] In some specific embodiments, step S400 specifically includes:

[0140] Step S400.1: Deploy a rotary encoder or photoelectric sensor and obtain the rotation angle value of the tool magazine motor.

[0141] The rotational angular position signal of the tool magazine motor is acquired by a rotary encoder installed on the spindle end of the tool magazine motor or by a photoelectric sensor installed on the circumferential structure of the tool magazine.

[0142] When a rotary encoder is used, the real-time acquired rotational angular position signal is input to the tool changer control system in the form of a pulse signal, and the real-time rotation angle value of the tool magazine motor is calculated based on the total angle range of the tool magazine's circumferential structure and the pulse resolution parameter.

[0143] When a photoelectric sensor is used, the photoelectric sensor detects the signals of the coded chips that are evenly spaced on the circumferential structure of the tool magazine, and inputs the acquired coded chip signals to the tool magazine changing control system. The real-time rotation angle of the tool magazine motor is calculated by the interval of the coded chip signals and the sampling time, and the real-time angular velocity and angular acceleration of the tool magazine motor are further calculated.

[0144] Step S400.2: Calculate the difference in rotation angle between the target tool and the tool magazine motor based on the rotation angle value of the tool magazine motor, and determine the deceleration trigger point and execute segmented deceleration control.

[0145] Based on the target tool number information in the tool change control command, the preset angle coordinate value of the target tool in the tool magazine circumference structure is obtained by querying the tool parameter database. The difference between the preset angle coordinate value of the target tool and the real-time rotation angle value of the tool magazine motor is calculated to obtain the rotation angle difference value between the current position of the tool magazine motor and the position of the target tool.

[0146] The speed curve planning module calculates the minimum rotation angle threshold required for the tool magazine motor to smoothly decelerate from its current operating speed to a stationary state based on the current real-time angular velocity and angular acceleration values ​​of the tool magazine motor. The minimum rotation angle threshold is 12° to 15°.

[0147] The tool changer control system continuously compares the rotation angle difference value with the minimum rotation angle threshold in real time. When the rotation angle difference value is less than or equal to the minimum rotation angle threshold, the tool magazine motor pre-deceleration control is immediately activated. During the pre-deceleration control, the output operating frequency of the tool magazine motor is gradually reduced through multiple frequency segments by the frequency converter.

[0148] The specific deceleration strategy is as follows: the current operating frequency of the tool magazine motor is reduced to 70%, 50% and 20% of the initial frequency in three consecutive stages. The duration of each frequency stage is 200 to 300 milliseconds. When the total load of the tool magazine exceeds 45 kg or the circumferential load vector magnitude of the tool magazine exceeds 3.5 kg·m, the total deceleration time of the three consecutive stages is extended to 900 milliseconds, and the output frequency of the tool magazine motor is reduced to below 8 Hz in the third deceleration stage.

[0149] Step S400.3: Perform micro-jitter compensation based on the rotation angle difference.

[0150] When the difference in rotation angle is less than 2°, the tool magazine motor enters the micro-jitter compensation control stage. The frequency converter reduces the output frequency of the tool magazine motor to below 2 Hz, and the tool magazine motor rotates slightly in both directions by alternately outputting low-frequency pulse signals in both directions.

[0151] The tool changer control system performs micro-rotation in both directions within a range of ±0.2°, with each micro-motion lasting from 80 to 100 milliseconds.

[0152] When the rotation angle difference of the tool magazine motor is stable within ±0.3° and remains stable for more than 150 milliseconds, it is determined that the tool magazine motor has been accurately positioned to the preset angle coordinate position of the target tool, and the position of the tool magazine motor is locked. At the same time, a tool pick-up preparation command is sent to the tool arm motor drive module.

[0153] In some specific embodiments, step S500 specifically includes:

[0154] Step S500.1: Drive the tool arm motor to perform the tool picking action based on the speed curve, deploy the flexible compensation mechanism, and perform the floating tool holding operation.

[0155] The inverter in the cutter arm motor drive module controls the cutter arm motor to perform the tool retrieval action according to the current speed curve of the cutter arm motor. The operating status of the cutter arm motor is set by the speed curve planning module, including: the initial acceleration is set to 0.4 m / s², and the initial operating frequency is set to 35 Hz.

[0156] When the front end of the cutter arm approaches the target tool, the cutter arm motor enters the pre-deceleration phase, and the operating frequency decreases gradually at a rate of 5 Hz per stage until the cutter arm gripping axis enters the alignment zone of the cutter cup's central axis.

[0157] A flexible compensation mechanism is set at the front end of the cutter arm. The flexible compensation mechanism includes an axial sliding sleeve, an elastic damping component, and a micro-displacement detection device. The flexible compensation mechanism is set on the cutter arm gripping shaft. The cutter arm gripping shaft can float axially when it contacts the cutter cup at the cutter cup clamping point through the cooperation of the axial sliding sleeve and the elastic damping component. The floating range does not exceed ±1.2 mm.

[0158] During the axial floating process of the tool arm gripping shaft, the elastic damping component provides buffering and absorption capacity for the tool arm gripping shaft, the micro-displacement detection device detects the axial floating amount of the tool arm gripping shaft in real time, and the tool magazine changing control system controls the tool arm motor to drive the tool arm gripping shaft at an operating frequency of less than 10 Hz during the floating compensation phase. The operating duration of the floating compensation phase is set to 200 milliseconds.

[0159] Step S500.2: Dynamically adjust the speed and torque during the clamping process based on the quality information and outer diameter information, and determine the completion and locking of the tool changing action based on the flexible compensation mechanism.

[0160] The tool magazine changing control system calls the tool parameter database to obtain the target tool's mass information and outer diameter information, and inputs the target tool's mass information and outer diameter information into the speed curve planning module. The speed curve planning module dynamically adjusts the clamping speed and torque of the tool arm motor based on the target tool's mass information and outer diameter information.

[0161] When the target tool's mass exceeds 1.8 kg or its outer diameter exceeds Φ80 mm, the operating acceleration of the tool arm motor is adjusted to 0.3 m / s², and the maximum operating frequency of the tool arm motor is limited to 45 Hz.

[0162] When the target tool's mass is less than or equal to 1.8 kg and its outer diameter is less than or equal to Φ80 mm, the operating acceleration of the tool arm motor will be maintained at 0.4 m / s², and the maximum operating frequency of the tool arm motor will be set to 60 Hz.

[0163] During the tool gripping process, the tool arm gripping axis moves slowly and at a constant speed when approaching the tool cup and when performing the tool-locking action. As the tool arm gripping axis moves away from the tool cup and toward the spindle, the speed gradually increases to the maximum allowable operating speed.

[0164] The micro-displacement detection device in the flexible compensation mechanism continuously detects the floating amount and force state of the tool arm gripping shaft, and monitors the floating amount data of the tool arm gripping shaft fed back by the micro-displacement detection device in real time.

[0165] When the axial float of the tool arm gripping axis is less than ±0.3 mm and the float remains stable for more than 150 milliseconds, the tool gripping action of the tool arm gripping axis is determined to be completed.

[0166] After determining that the tool arm gripping shaft has completed its tool-grabbing action, the tool magazine changing control system will immediately control the tool arm motor to enter the locking stage. The locking control circuit in the tool arm motor drive module will trigger the locking pin mechanism to enter the side groove of the tool arm gripping shaft.

[0167] In some specific embodiments, step S600 specifically includes:

[0168] Step S600.1: Based on the tool arm motor drive module, control the tool arm motor to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup.

[0169] After the tool arm gripping axis completes the gripping and locking action of the target tool, the frequency converter in the tool arm motor drive module controls the tool arm motor to move the target tool to the spindle interface position according to the speed curve planned by the speed curve planning module.

[0170] During the docking process of the target tool being loaded into the spindle interface, the operating frequency of the tool arm motor is gradually reduced to no more than 8 Hz. After the target tool is inserted into the spindle interface, the tool arm gripping shaft releases the locking pin mechanism, loosens the locking clamp on the target tool, and completes the action of loading the target tool into the spindle.

[0171] Based on load sensors and micro-displacement detection devices, the docking status between the target tool and the spindle interface is monitored in real time. After confirming that the target tool is stably installed in the spindle interface, the spindle tool status information is marked as assembled.

[0172] The tool magazine changing control system controls the tool arm motor to move the old tool from the spindle position to the target empty tool cup position in the tool magazine according to the speed curve planned by the speed curve planning module. When the old tool approaches the alignment area of ​​the target empty tool cup, the operating frequency of the tool arm motor is gradually reduced to no more than 10 Hz, and the tool arm gripping axis enters the floating compensation stage controlled by the flexible compensation mechanism.

[0173] During the floating compensation phase, the tool arm gripping shaft, through the axial sliding sleeve and elastic damping component of the flexible compensation mechanism, buffers the insertion of the old tool into the target empty tool cup within an axial floating range of ±1.2 mm.

[0174] The axial displacement data of the tool arm gripping shaft is detected in real time by the micro-displacement detection device of the flexible compensation mechanism. When the axial displacement data of the tool arm gripping shaft is detected to be stable within ±0.3 mm and remains stable for more than 150 milliseconds.

[0175] The tool magazine changer control system controls the tool arm gripping shaft release locking pin mechanism to release the old tool and lock the position of the tool arm motor, updating the tool status information of the target empty tool cup to "loaded".

[0176] Step S600.2: Update the overall mass and total load data of the tool magazine and the circumferential off-center load vector of the tool magazine based on the tool parameter database.

[0177] The tool parameter database records the number, mass, and outer diameter of the old tool when it is returned to the target empty tool cup. The number of the target tool newly installed in the spindle is updated to the tool currently assembled in the spindle. Based on the updated mass information of all tools in the tool parameter database, the total mass load of the current tool magazine is recalculated.

[0178] Based on the specific distribution angle of all tools in the tool magazine on the circumferential structure of the tool magazine, the updated circumferential load vector of the tool magazine is calculated by the circumferential load calculation algorithm. When the updated total load data of the tool magazine exceeds 45 kg or the modulus of the tool magazine circumferential load vector exceeds 3.5 kg·m, the tool magazine load alarm is immediately triggered and the low-impact control mode is automatically entered.

[0179] Step S600.3: Based on the tool magazine circumferential off-center load vector, perform automatic tool position rearrangement and off-center load balancing, generate tool change completion status information, and output the current status data of the tool magazine.

[0180] When the magnitude of the tool magazine circumferential off-center load vector exceeds 3.5 kg·m, the tool position rearrangement strategy will be automatically activated.

[0181] Based on the tool parameter database, heavy tools with a mass exceeding 1.8 kg were identified and marked as requiring tool rearrangement.

[0182] By analyzing the distribution of empty tool cups in the tool magazine's circumferential structure, a tool position rearrangement optimization algorithm is invoked to determine multiple tool position rearrangement paths. Based on the analysis of multiple tool position rearrangement paths, the tool position rearrangement path with the lowest magnitude of the tool magazine's circumferential off-center load vector is selected as the execution strategy. According to the selected tool position rearrangement path, the tool arm motor is driven by the tool arm motor drive module to gradually perform the heavy tool repositioning operation.

[0183] Prioritize moving heavy tools marked as needing rearrangement to symmetrical or relatively balanced positions on the tool magazine's circumferential structure, with the goal of reducing the circumferential load vector magnitude of the tool magazine to below 2.0 kg·m.

[0184] After each reordering operation of a single tool position is completed, the tool parameter database is updated again, and the tool load analysis module is called again to calculate the total load data of the tool magazine and the tool magazine circumferential load vector. The reordering operation will stop when the magnitude of the tool magazine circumferential load vector meets the target threshold of no more than 2.0 kg·m or there are no more feasible tool position reordering paths.

[0185] After completing the actions of loading the target tool into the spindle interface, returning the old tool to the tool cup position, updating the tool data, and rearranging the tool position, the current status of the tool magazine is marked as tool change complete.

[0186] When the tool change is complete, the data of the current tool change action will be automatically recorded.

[0187] The data record for the current tool change action includes: the timestamp of the tool change operation completion, the target tool number information, the old tool number information, the current spindle tool status, the total mass and load data of the current tool magazine, the current tool magazine circumferential load vector magnitude value, the tool position rearrangement action record, and the current tool magazine tool distribution status diagram.

[0188] Please see Figure 2 , Figure 2 A framework diagram of a tool changer control system based on variable frequency speed regulation is provided for embodiments of this application.

[0189] The tool changer control system based on variable frequency speed regulation specifically includes the following modules:

[0190] The tool change control deployment module is used to acquire tool change commands and tool information, identify the machining stage, collect tool arm load information, query and calculate real-time parameters and historical tool data, calculate the tool magazine circumferential load vector, and determine and prompt the load threshold.

[0191] The machining identification task module is used to generate speed curves for the tool magazine motor and the tool arm motor based on mechanical load data, and to make corrections and adjustments. Based on the speed curve of the tool magazine motor, the synchronous operation parameters of the tool arm motor are set.

[0192] The load acquisition and judgment module is used to control the inverter to start the tool magazine motor and the tool arm motor based on the speed curve, adjust the operating frequency, monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation of vector control based on the current and torque data, and handle abnormal operating conditions.

[0193] The variable frequency control module is designed to deploy rotary encoders or photoelectric sensors to obtain the rotation angle value of the tool magazine motor. Based on the rotation angle value of the tool magazine motor, the rotation angle difference between the target tool and the tool magazine motor is calculated, the deceleration trigger point is determined, and segmented deceleration control is executed. Micro-amplitude jitter compensation is performed based on the rotation angle difference.

[0194] The clamping adjustment and correction module is used to drive the tool arm motor to perform the tool picking action based on the speed curve, deploy a flexible compensation mechanism, and perform a floating tool locking operation. It dynamically adjusts the speed and torque during the clamping process based on quality information, and determines the completion and locking of the tool changing action based on the flexible compensation mechanism.

[0195] The tool change data update module is used to control the tool arm motor to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup based on the tool arm motor drive module. It updates the overall mass and total load data of the tool magazine and the tool magazine circumferential load vector based on the tool parameter database. Based on the tool magazine circumferential load vector, it performs automatic tool position rearrangement and load balancing, generates tool change completion status information, and outputs the current status data of the tool magazine.

[0196] In practical applications, the tool magazine changing control system includes a tool arm motor, a frequency converter control unit, a speed curve planning module, an angle difference judgment module, a flexible compensation mechanism, and the tool magazine changing control system itself. The tool arm motor is electrically connected to the frequency converter control unit and drives the tool arm to move after receiving the operating frequency command from the tool magazine changing control system. The tool magazine changing control system integrates a speed curve planning module to plan the operating frequency change path to adapt to different tool changing stages, realizing flexible acceleration and deceleration control of the tool arm motor. The tool magazine changing control system further connects the angle difference judgment module and the flexible compensation mechanism to achieve precise tool alignment and dynamic adjustment of clamping action.

[0197] Secondly, the tool changer control system has a preset machining stage identification logic to determine whether the current machine tool operation status has entered the tool change preparation stage. When the machining stage identification logic determines that the current state is machining termination or pre-tool change, the speed curve planning module is activated to set the operating frequency curve according to the tool arm rotation path. The operating frequency curve adopts a three-segment structure, including an initial acceleration segment, a constant speed segment, and a deceleration segment. The frequency rise slope of the tool arm motor in the acceleration segment is set to 1.0 Hz / s, and the maximum operating frequency is 80 Hz. The operating frequency at the end of the deceleration segment is no higher than 10 Hz to ensure accuracy and safety when approaching the tool position.

[0198] Next, the tool changer control system connects with the current acquisition module and the tool magazine position encoder to collect the real-time current value of the tool arm motor and the tool arm position data. This data is used to calculate the circumferential load distribution of the tool magazine. The system sets the circumferential off-center load judgment threshold as follows: if the ratio of the peak current on one side of the tool magazine to the average current on the other side exceeds 1.4 times, it is considered that there is an off-center load. When a circumferential off-center load is judged, the speed curve planning module dynamically adjusts the duration of the acceleration segment of the tool arm motor to extend its rise period in order to avoid large inertia impact.

[0199] Subsequently, the angle difference judgment module compares the current position of the tool arm with the angle of the target tool position. The tool magazine changing control system adjusts the output frequency of the inverter according to the judgment result. When the angle difference is less than or equal to 3°, the system immediately starts the deceleration control logic, so that the frequency of the tool arm motor decreases at a slope of 0.5 Hz / s until the operating frequency drops below 8 Hz, and continues to run stably for more than 2 seconds to complete the precise alignment. This logic effectively prevents the risk of tool position deviation or jamming due to excessive inertia.

[0200] Then, a flexible compensation mechanism is set at the end of the tool arm, including a floating adjustment component and an adaptive clamping component. After the tool arm is aligned, the floating adjustment component enables a displacement compensation capability of ±1.5mm to correct minor offsets of the tool holder. The adaptive clamping component then completes the clamping action. The clamping force threshold for the clamping action is set at 45N to ensure that the tool is firmly fixed and will not damage the tool holder. This compensation adjustment mechanism is started by the tool magazine changer control system, and the execution status is confirmed based on the feedback signal.

[0201] Finally, the tool change completion determination module in the tool magazine tool change control system is used to determine the completion of the tool change based on the stop status of the tool arm motor, the feedback from the position sensor of the clamping component, and the reset status of the flexible compensation mechanism. The determination criteria include the motor operating frequency being 0 Hz, the clamping sensor feedback value being in the "clamping closed" state, and the displacement of the flexible compensation mechanism returning to the center 0 mm position. When all three of the above states are met, the tool magazine tool change control system writes the current tool position number and completion time into the tool change status record cache and updates the current tool status to the "in place" state, providing a traceable record for subsequent tool calls.

[0202] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A tool changer control method based on variable frequency speed regulation, characterized in that, Includes the following steps: S100: Obtain tool change instructions and tool information, identify the machining stage, collect tool arm load information, query and calculate real-time parameters and historical tool data, calculate the tool magazine circumferential load vector, and determine and prompt the load threshold. S200: Generate speed curves for the tool magazine motor and the tool arm motor based on mechanical load data, and make corrections and adjustments. Set the synchronous operation parameters of the tool arm motor based on the speed curve of the tool magazine motor. S300: Based on the speed curve, the inverter starts the tool magazine motor and the tool arm motor, adjusts the operating frequency, monitors the current and torque data of the tool magazine motor and the tool arm motor, performs automatic torque compensation of vector control based on the current and torque data, and handles abnormal operating conditions. S400 deploys a rotary encoder or photoelectric sensor to obtain the rotation angle value of the tool magazine motor, calculates the rotation angle difference between the target tool and the tool magazine motor based on the rotation angle value of the tool magazine motor, determines the deceleration trigger point and executes segmented deceleration control, and performs micro-amplitude jitter compensation based on the rotation angle difference; S500: Drives the tool arm motor based on the speed curve to perform the tool picking action, deploys a flexible compensation mechanism, and performs a floating tool locking operation. It dynamically adjusts the speed and torque during the clamping process based on the quality information, and determines the completion and locking of the tool changing action based on the flexible compensation mechanism. S600: Based on the tool arm motor drive module, the tool arm motor is controlled to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup. Based on the tool parameter database, the overall mass and total load data of the tool magazine and the tool magazine circumferential load vector are updated. Based on the tool magazine circumferential load vector, the tool position is automatically rearranged and the load is balanced. The tool change completion status information is generated and the current status data of the tool magazine is output. Specifically, S500 is as follows: S500.1: The tool arm motor is driven by the speed curve to perform the tool picking action, a flexible compensation mechanism is deployed, and a floating tool holding operation is performed; The inverter in the cutter arm motor drive module controls the cutter arm motor to perform the tool retrieval action according to the current speed curve of the cutter arm motor. The operating status of the cutter arm motor is set by the speed curve planning module, including: the initial acceleration is set to 0.4 m / s², and the initial operating frequency is set to 35 Hz. When the front end of the cutter arm approaches the target tool, the cutter arm motor enters the pre-deceleration stage, and the operating frequency decreases step by step at a rate of 5 Hz per stage until the cutter arm gripping axis enters the alignment zone of the cutter cup center axis. A flexible compensation mechanism is set at the front end of the cutter arm. The flexible compensation mechanism includes an axial sliding sleeve, an elastic damping component, and a micro-displacement detection device. The flexible compensation mechanism is set on the cutter arm gripping shaft. The cutter arm gripping shaft can float axially when it contacts the cutter cup at the cutter cup locking point through the cooperation of the axial sliding sleeve and the elastic damping component. The floating range does not exceed ±1.2 mm. During the axial floating process of the tool arm gripping shaft, the elastic damping component provides buffering and absorption capacity for the tool arm gripping shaft, the micro-displacement detection device detects the axial floating amount of the tool arm gripping shaft in real time, and the tool magazine changing control system controls the tool arm motor to drive the tool arm gripping shaft at an operating frequency of less than 10 Hz during the floating compensation phase. The operating duration of the floating compensation phase is set to 200 milliseconds. S500.

2. Dynamically adjust the speed and torque during the clamping process based on the quality information and outer diameter information, and determine the completion and locking of the tool changing action based on the flexible compensation mechanism; The tool magazine changing control system calls the tool parameter database to obtain the target tool's mass information and outer diameter information, and inputs the target tool's mass information and outer diameter information into the speed curve planning module. The speed curve planning module dynamically adjusts the clamping speed and torque of the tool arm motor based on the target tool's mass information and outer diameter information. During the tool gripping process, the tool arm gripping axis moves slowly and at a constant speed when approaching the cutter cup and when performing the tool-holding action. As the tool arm gripping axis moves away from the cutter cup and toward the spindle, the speed gradually increases to the maximum allowable operating speed. When the axial float of the tool arm gripping axis is less than ±0.3 mm and the float remains stable for more than 150 milliseconds, the tool magazine changing control system determines that the tool gripping action of the tool arm gripping axis has been completed. After determining that the tool arm gripping shaft has completed its tool-grabbing action, the tool magazine changing control system will immediately control the tool arm motor to enter the locking stage. The locking control circuit in the tool arm motor drive module will trigger the locking pin mechanism to enter the side groove of the tool arm gripping shaft.

2. The tool changer control method based on variable frequency speed regulation as described in claim 1, characterized in that, Specifically, S100 is as follows: S100.1 Obtain tool change instructions and tool information, and identify the machining stage; Upon receiving the tool change control command from the upper-level CNC control system, the tool information acquisition module is activated through the tool magazine tool change control system to acquire the tool change control command; The tool magazine tool changing control system includes: an upper-level numerical control control system, a tool information acquisition module, a process stage identification module, a tool arm current detection module, a tool parameter database, a tool load analysis module, a speed curve planning module, a tool magazine motor drive module, a tool arm motor drive module, a self-learning optimization algorithm module, a motor drive status detection module, and a tool magazine structure vibration detection module. The tool change control command includes: the number, quality, outer diameter, position of the current tool on the spindle, and the corresponding tool position in the tool magazine of the target tool; The process stage identification module obtains the processing stage label information from the upper CNC control system, including: roughing stage and finishing stage; When the current machining stage is identified as the finishing stage, the tool magazine tool changer control system will be set to the machining stability priority mode. When it is identified as the roughing stage, the tool magazine tool changer control system is allowed to use a higher speed tool change mode. S100.

2. Collect tool arm load information, query and calculate real-time parameters and tool history data, calculate tool magazine circumferential load vector, and determine and prompt load threshold. Based on the acquired processing stage label information, load sensors deployed at the load feedback points of the cutter arm drive structure are used to collect mechanical load data of the cutter arm in real time. Using the tool parameter database, historical usage records, static quality information, and dynamic load distribution data of the tool are extracted based on the current spindle tool number information and the next target tool number information to be replaced. The mass information of each tool in the tool magazine is queried in turn, and the mass information of all tools in the tool magazine is accumulated and calculated through the tool load analysis module to obtain the total mass load data of the tool magazine. The tool load analysis module further determines the tool magazine circumferential load vector based on the specific distribution angle of each tool in the tool magazine on the tool magazine circumferential structure and the circumferential off-center load calculation algorithm. The direction and intensity of the center of gravity shift of the overall load of the tool magazine in the circumferential direction are determined by the circumferential load vector of the tool magazine. The larger the value of the circumferential load vector of the tool magazine, the higher the degree of unevenness of the overall load distribution of the tool magazine. The tool load analysis module compares the currently calculated total load data of the tool magazine with the preset tool magazine load threshold. When the total load of the tool magazine exceeds the preset tool magazine load threshold of 45 kg, an overload warning message is immediately issued. When the magnitude of the tool magazine circumferential off-center load vector exceeds the set off-center load balance threshold of 3.5 kg·m, an off-center load warning message is triggered.

3. The tool changer control method based on variable frequency speed regulation as described in claim 1, characterized in that, Specifically, S200 is as follows: S200.

1. Generate speed curves for the tool magazine motor and the tool arm motor based on mechanical load data; The speed curve planning module is invoked to generate multi-segment acceleration and deceleration curves for the tool magazine motor and the tool arm motor, based on the mass information, the total mass and load data of the tool magazine, and the circumferential off-center load vector of the tool magazine as input conditions. The multi-segment acceleration / deceleration curve includes five consecutive operating speed segments, which are: starting frequency segment, acceleration segment, constant speed segment, pre-deceleration segment, and braking segment. The speed curve planning module determines the operating parameters of the tool magazine motor based on the overall mass and total load data of the tool magazine and the circumferential off-center load vector of the tool magazine. The operating parameters of the tool magazine motor include: When the total weight of the tool magazine is less than 30 kg and the magnitude of the circumferential load vector of the tool magazine is less than 1.5 kg·m, the acceleration of the tool magazine motor is set to 0.8 m / s², and the maximum operating frequency of the tool magazine motor is set to 80 Hz. When the total load of the tool magazine is between 30 kg and 45 kg or the circumferential load vector magnitude of the tool magazine is between 1.5 kg·m and 3.5 kg·m, the acceleration of the tool magazine motor is set to 0.5 m / s², and the maximum operating frequency of the tool magazine motor is set to 60 Hz. When the total load of the tool magazine exceeds 45 kg or the circumferential load vector magnitude of the tool magazine exceeds 3.5 kg·m, the acceleration of the tool magazine motor is limited to 0.3 m / s², and the maximum operating frequency of the tool magazine motor is limited to 45 Hz. It will automatically enter the low-impact mode, and the frequency of the tool magazine tool changing rhythm is limited to no more than 10 times per minute. S200.2 Correct and adjust the speed curve based on the label information of the processing stage; When the process stage identification module identifies the current processing stage label information as roughing stage, it allows the tool magazine motor and tool arm motor to operate according to the operating parameters of the tool magazine motor. When the process stage identification module identifies the current processing stage label information as the finishing stage, the acceleration correction coefficient of the tool magazine motor and the tool arm motor is set to 0.5, and the maximum operating frequency of the tool magazine motor and the tool arm motor is corrected to 80% of the originally planned maximum operating frequency; When in the finishing stage, the strategy of preparing tools in advance is prohibited. The tool change action of the tool magazine motor and tool arm motor should be executed only after the current finishing instruction is completed. S200.3, Set the synchronous operation parameters of the tool arm motor based on the speed curve of the tool magazine motor; Before the current spindle tool completes machining and enters the tool change preparation stage, the tool arm motor remains in a waiting and locked state. After the tool magazine motor completes the rotational positioning action of the target tool, the tool arm motor is started through the speed curve planning module and the tool magazine motor status feedback to perform the tool retrieval operation.

4. The tool changer control method based on variable frequency speed regulation as described in claim 1, characterized in that, Specifically, S300 is as follows: S300.1, Based on the speed curve, the frequency converter starts the tool magazine motor and the tool arm motor, and adjusts the operating frequency; The speed curves of the tool magazine motor and the tool arm motor are generated and cached in the high-speed cache register by the speed curve planning module. Start commands are sent to the frequency converters in the tool magazine motor drive module and the tool arm motor drive module. After receiving the start commands, the tool magazine motor drive module and the tool arm motor drive module output low start frequency control signals to the tool magazine motor and the tool arm motor through the frequency converter. The initial value of the low start-up frequency control signal is set to be in the range of 5 Hz to 10 Hz. The specific selection of the initial value of the start-up frequency is determined based on the total weight data of the tool magazine: when the total weight data of the tool magazine exceeds 30 kg, the initial value of the start-up frequency is 5 Hz; when the total weight data of the tool magazine is less than or equal to 30 kg, the initial value of the start-up frequency is 10 Hz. After the tool magazine motor and the tool arm motor complete the soft start and enter the acceleration zone, the output operating frequency of the tool magazine motor and the tool arm motor is gradually increased according to the multi-segment acceleration and deceleration curves planned by the speed curve planning module. S300.2 Monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation for vector control based on the current and torque data, and handle abnormal operating conditions. During the gradual increase of frequency, the current sensor and torque sensor integrated in the tool magazine motor drive module and the tool arm motor drive module are used to collect the actual operating current data and real-time torque data of the tool magazine motor and the tool arm motor in real time at a frequency of 50 milliseconds. The current sensor and torque sensor are respectively installed inside the tool magazine motor drive module and the tool arm motor drive module; The vector control torque automatic compensation algorithm analyzes the actual operating current data and real-time torque data of the tool magazine motor and the tool arm motor in real time. It compares the actual operating current data and real-time torque data with the standard operating data planned by the speed curve planning module and calculates the real-time torque compensation value. If the real-time torque data of the tool magazine motor or the tool arm motor is lower than 90% of the planned standard operating data during the acceleration phase, the inverter output power will be automatically increased to increase the torque output of the tool magazine motor or the tool arm motor. If the real-time torque data exceeds 110% of the planned standard operating data, the inverter output power will be automatically reduced. During the multi-stage variable frequency soft start and step-by-step acceleration process, the operating frequency deviation and real-time load change of the tool magazine motor and the tool arm motor are monitored in real time, and abnormal state threshold parameters are set: when the operating frequency deviation of the tool magazine motor exceeds ±5 Hz, or the real-time load change of the tool arm motor exceeds ±0.4 kg, the speed curve correction interruption mechanism is immediately activated. After the speed curve correction interruption mechanism is started, the operating frequency is gradually reduced by controlling the tool magazine motor and the tool arm motor with an abnormal speed reduction strategy of reducing the frequency by 5 Hz in each segment, until the abnormal state is completely eliminated. Once the abnormal condition is completely eliminated, the acceleration process will be restarted at a reduced frequency until the operating status of the tool magazine motor and the tool arm motor is fully matched with the planned speed curve, and then the subsequent tool changing action will continue.

5. The tool changer control method based on variable frequency speed regulation as described in claim 1, characterized in that, Specifically, S400 is: S400.1 Deploy a rotary encoder or photoelectric sensor and obtain the rotation angle value of the tool magazine motor; The rotational angular position signal of the tool magazine motor is acquired by a rotary encoder installed on the spindle end of the tool magazine motor or by a photoelectric sensor installed on the circumferential structure of the tool magazine. When a rotary encoder is used, the real-time acquired rotational angular position signal is input to the tool changer control system in the form of a pulse signal, and the real-time rotational angle value of the tool magazine motor is calculated based on the total angle range of the tool magazine's circumferential structure and the pulse resolution parameter. When a photoelectric sensor is used, the photoelectric sensor detects the signals of the coded chips that are evenly spaced on the circumferential structure of the tool magazine, inputs the acquired coded chip signals, and calculates the real-time rotation angle value of the tool magazine motor by the interval of the coded chip signals and the sampling time, and further calculates the real-time angular velocity value and angular acceleration value of the tool magazine motor. S400.2 Calculate the difference in rotation angle between the target tool and the tool magazine motor based on the numerical value of the rotation angle of the tool magazine motor, and determine the deceleration trigger point and execute segmented deceleration control; Based on the target tool number information in the tool change control command, the preset angle coordinate value of the target tool in the tool magazine circumference structure is obtained by querying the tool parameter database. The difference between the preset angle coordinate value of the target tool and the real-time rotation angle value of the tool magazine motor is calculated to obtain the rotation angle difference value between the current position of the tool magazine motor and the position of the target tool. Based on the current real-time angular velocity and angular acceleration values ​​of the tool magazine motor, the speed curve planning module calculates the minimum rotation angle threshold required for the tool magazine motor to smoothly decelerate from its current operating speed to a stationary state. The minimum rotation angle threshold is 12° to 15°. The tool magazine changing control system continuously compares the value of the rotation angle difference with the minimum rotation angle threshold in real time. When the value of the rotation angle difference is less than or equal to the minimum rotation angle threshold, the tool magazine motor pre-deceleration control is immediately started. When the pre-deceleration control is executed, the output operating frequency of the tool magazine motor is gradually reduced by the frequency converter in multiple segments. S400.3, Perform micro-jitter compensation based on the difference in rotation angle; When the difference in rotation angle is less than 2°, the tool magazine motor enters the micro-jitter compensation control stage. The output frequency of the tool magazine motor is reduced to below 2 Hz by the frequency converter. By alternately outputting low-frequency pulse signals in the forward and reverse directions, the tool magazine motor rotates slightly in the forward and reverse directions. When the rotation angle difference of the tool magazine motor is stable within ±0.3° and remains stable for more than 150 milliseconds, it is determined that the tool magazine motor has been accurately positioned to the preset angle coordinate position of the target tool, and the position of the tool magazine motor is locked. At the same time, a tool pick-up preparation command is sent to the tool arm motor drive module.

6. The tool changer control method based on variable frequency speed regulation as described in claim 1, characterized in that, Specifically, S600 is as follows: S600.1, Based on the tool arm motor drive module, the tool arm motor is controlled to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup; After the tool arm gripping axis completes the gripping and locking action of the target tool, the tool magazine changing control system controls the tool arm motor to move the target tool to the spindle interface position according to the speed curve planned by the speed curve planning module through the frequency converter in the tool arm motor drive module. During the docking process of the target tool being loaded into the spindle interface, the operating frequency of the tool arm motor is gradually reduced to no more than 8 Hz. After the target tool is inserted into the spindle interface, the tool arm gripping shaft releases the locking pin mechanism, loosens the locking clamp on the target tool, and completes the action of loading the target tool into the spindle. The tool magazine changing control system controls the tool arm motor to move the old tool from the spindle position to the target empty tool cup position in the tool magazine according to the speed curve planned by the speed curve planning module. When the old tool approaches the alignment area of ​​the target empty tool cup, the operating frequency of the tool arm motor is gradually reduced to no more than 10 Hz, and the tool arm gripping axis enters the floating compensation stage controlled by the flexible compensation mechanism. During the floating compensation phase, the tool arm gripping shaft moves through the axial sliding sleeve of the flexible compensation mechanism and the elastic damping component. The axial float data of the tool arm gripping shaft is detected in real time by the micro-displacement detection device of the flexible compensation mechanism. When the axial float data of the tool arm gripping shaft is detected to be stable within ±0.3 mm and remains stable for more than 150 milliseconds; S600.2 Update the overall mass and total load data of the tool magazine and the circumferential off-center load vector of the tool magazine based on the tool parameter database; The tool parameter database records the number, mass, and outer diameter of the old tool when it is returned to the target empty tool cup. The number of the target tool newly installed in the spindle is updated to the tool currently assembled in the spindle. Based on the updated mass information of all tools in the tool parameter database, the total mass load data of the current tool magazine is recalculated. Based on the specific distribution angle of all tools in the tool magazine on the circumferential structure of the tool magazine, the updated circumferential load vector of the tool magazine is calculated by the circumferential load calculation algorithm. When the updated total load data of the tool magazine exceeds 45 kg or the modulus of the tool magazine circumferential load vector exceeds 3.5 kg·m, the tool magazine load alarm is immediately triggered and the low impact control mode is automatically entered. S600.3: Based on the tool magazine's circumferential off-center load vector, automatically rearrange the tool position and balance the off-center load, generate tool change completion status information, and output the current status data of the tool magazine; When the magnitude of the tool magazine circumferential off-center loading vector exceeds 3.5 kg·m, the tool position rearrangement strategy will be automatically activated. Based on the tool parameter database, heavy tools with a mass exceeding 1.8 kg were identified and marked as: tools requiring rearrangement; By analyzing the distribution of empty tool cups in the tool magazine's circumferential structure, a tool position rearrangement optimization algorithm is called to determine multiple tool position rearrangement paths. Based on the analysis of multiple tool position rearrangement paths, the tool position rearrangement path with the lowest magnitude of the tool magazine's circumferential off-center load vector is selected as the execution strategy. According to the selected tool position rearrangement path, the tool arm motor is driven by the tool arm motor drive module to gradually perform the heavy tool repositioning operation. Prioritize moving heavy tools marked as needing rearrangement to symmetrical angular positions or relatively balanced positions on the tool magazine circumferential structure, with the goal of reducing the magnitude of the tool magazine circumferential off-center load vector to within 2.0 kg·m; After each reordering operation of a single tool position is completed, the tool parameter database is updated again, and the tool load analysis module is called again to calculate the total load data of the tool magazine and the tool magazine circumferential load vector. The reordering operation will stop when the magnitude of the tool magazine circumferential load vector meets the target threshold of no more than 2.0 kg·m or there are no more feasible tool position reordering paths. After the target tool of the tool arm motor is loaded into the spindle interface, the old tool is returned to the tool cup position, the tool data is updated and the tool position is rearranged, the current status of the tool magazine is marked as tool change completed; When the tool change is complete, the data of the current tool change action will be automatically recorded.

7. A tool changer control system based on variable frequency speed regulation, implemented according to any one of claims 1-6, characterized in that, Specifically, it includes the following modules: The tool change control deployment module is used to acquire tool change commands and tool information, identify the machining stage, collect tool arm load information, query and calculate real-time parameters and historical tool data, calculate the tool magazine circumferential load vector, and determine and prompt the load threshold. The machining identification task module is used to generate speed curves for the tool magazine motor and the tool arm motor based on mechanical load data, and to make corrections and adjustments. Based on the speed curve of the tool magazine motor, the synchronous operation parameters of the tool arm motor are set. The load acquisition and judgment module is used to control the frequency converter to start the tool magazine motor and the tool arm motor based on the speed curve, adjust the operating frequency, monitor the current and torque data of the tool magazine motor and the tool arm motor, perform automatic torque compensation of vector control based on the current and torque data, and handle abnormal operating conditions. The variable frequency control module is designed to deploy rotary encoders or photoelectric sensors and obtain the rotation angle value of the tool magazine motor. Based on the rotation angle value of the tool magazine motor, the rotation angle difference between the target tool and the tool magazine motor is calculated, the deceleration trigger point is determined and segmented deceleration control is executed, and micro-amplitude jitter compensation is performed based on the rotation angle difference. The clamping adjustment and correction module is used to drive the tool arm motor to perform the tool picking action based on the speed curve, deploy the flexible compensation mechanism, and perform the floating tool locking operation. It dynamically adjusts the speed and torque during the clamping process based on the quality information, and determines the completion and locking of the tool changing action based on the flexible compensation mechanism. The tool change data update module is used to control the tool arm motor to perform the action of loading the target tool into the spindle and the action of putting the old tool back into the tool cup based on the tool arm motor drive module. It updates the overall mass and total load data of the tool magazine and the tool magazine circumferential load vector based on the tool parameter database. Based on the tool magazine circumferential load vector, it performs automatic tool position rearrangement and load balancing, generates tool change completion status information, and outputs the current status data of the tool magazine.

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