CN102866665A - Multi-axial synchronous control system and method for all-electric bending machine - Google Patents

Abstract

The invention discloses a multi-axis synchronous control system and control method for an all-electric bending machine, including a motion control board, a numerical control system, and several groups of slider driving mechanisms; each group of slider driving mechanisms includes a servo driver, a permanent Magnetic synchronous servo motor, synchronous belt transmission mechanism, ball screw and grating scale; the permanent magnet synchronous servo motor is connected to the ball screw through the synchronous belt transmission mechanism, and the bottom end of the ball screw is installed on the top of the bending machine slider; The grating ruler is installed on the back of the bending machine slider and is on the same vertical axis as the ball screw; the permanent magnet synchronous servo motor is also connected to the servo driver, and the servo driver and the grating ruler are respectively connected to the numerical control system through the motion control board. The adoption of the system can significantly improve the synchronous performance and bending positioning accuracy of multiple permanent magnet synchronous servo motors.

Description

Multi-axis synchronous control system and control method for all-electric bending machine

technical field

The invention relates to the technical field of industrial automation control and bending machine numerical control, in particular to a multi-axis synchronous control system and control method for an all-electric bending machine. the

Background technique

Sheet metal bending is an important type of sheet metal processing. This process adopts a complete set of upper and lower molds, and the metal sheet is plastically deformed and folded into a sheet metal part with a predetermined angle by extrusion in a cold state. The process has the advantages of good versatility, simple process and high forming quality, and has been widely used in electrical appliances, shipbuilding, aviation, heavy machinery manufacturing and other industries. the

In order to realize the numerical control of the bending machine, improve the positioning accuracy and synchronization accuracy, and overcome the inherent shortcomings of the traditional hydraulic bending machine, the all-electric bending machine directly driven by the servo motor has become the mainstream. The upper mold slider of the low-power all-electric bending machine only needs two servo motors to be synchronously driven and controlled, while for high-power to achieve a bending pressure of 1000KN and above, it is necessary to use multiple servo motors to synchronize on a slider (rigid body) drive. the

However, in the actual use of high-power all-electric bending machines, there is a phenomenon of position asynchrony caused by the unbalanced force of each motor, which leads to strong mechanical coupling, and strong mechanical coupling will cause moving parts such as sliders to twist. Inclined, aggravate the wear of the transmission components such as the screw, reduce the machining accuracy and the life of the machine tool, and damage the driving components and the traveling mechanism in severe cases. In order to prevent the above situation from happening, the drive slider needs multi-axis synchronous speed position linkage. Therefore, the study of multi-axis motor position synchronization control system is an indispensable link in the development of high-power all-electric bending machine. the

Contents of the invention

The purpose of the present invention is to provide a multi-axis synchronous control system for all-electric bending machines in view of the technical deficiencies of existing industrial automation control and bending machine numerical control. the

Further, the present invention provides a control method for a multi-axis synchronous control system of an all-electric bending machine. the

For realizing above-mentioned purpose of the invention, the technical scheme that the present invention adopts is:

Provide a multi-axis synchronous control system for all-electric bending machines, including motion control boards, numerical control systems and several sets of slider drive mechanisms; each set of slider drive mechanisms includes servo drives, permanent magnet synchronous servo motors, synchronous Belt transmission mechanism, ball screw and grating scale; the permanent magnet synchronous servo motor is connected with the ball screw through a synchronous belt transmission mechanism, and the bottom end of the ball screw is installed on the top of the bending machine slider; the grating scale Installed on the back of the bending machine slider and on the same vertical axis as the ball screw; the permanent magnet synchronous servo motor is also connected to the servo driver, and the servo driver and the grating ruler are respectively connected to the numerical control system through the motion control board.

Preferably, the three-phase output of the servo driver is connected to the power supply side of the servo motor; the X2 function port of the servo driver is connected to the motion control board through a cable, and the encoder input port of the servo driver is connected through a cable The wire is connected with the output end of the rotary encoder of the permanent magnet synchronous servo motor. the

Preferably, the numerical control system includes an industrial computer and an embedded touch screen; the embedded touch screen is connected to the industrial computer; the motion control board includes a switching value control board and a speed control board; the servo driver and the grating scale It is connected with the speed control board, and the switch control board is connected to the upper and lower stroke limit switches of the slider of the bending machine through cables; the switch control board and the speed control board are both connected to the inside of the industrial control computer through optical fibers PCI module. the

Preferably, the synchronous belt transmission mechanism includes a first belt gear, a timing belt and a second belt gear; the first belt gear is installed on the output shaft of the permanent magnet synchronous servo motor, and the second belt gear is installed on the nut of the ball screw On, the second belt gear is connected with the first belt gear through the timing belt. the

Preferably, the length of the bending machine slider is greater than 3000mm. the

Preferably, the number of the slider driving mechanisms is four, which are respectively the first slider driving mechanism, the second slider driving mechanism, the third slider driving mechanism and the fourth slider driving mechanism; the first slider driving mechanism The mechanism includes the first servo driver, the first permanent magnet synchronous servo motor, the first synchronous belt transmission mechanism, the first ball screw and the first grating scale; the second slider driving mechanism includes the second servo driver, the second permanent magnet synchronous The servo motor, the second synchronous belt transmission mechanism, the second ball screw and the second grating scale; the third slider driving mechanism includes the third servo driver, the third permanent magnet synchronous servo motor, the third synchronous belt transmission mechanism, the third The ball screw and the third grating scale; the fourth slider driving mechanism includes a fourth servo driver, a fourth permanent magnet synchronous servo motor, a fourth synchronous belt transmission mechanism, a fourth ball screw and a fourth grating scale. the

Further, the present invention provides a multi-axis synchronous control method for an all-electric bending machine. The industrial computer includes a motion control module, a PID module, a fuzzy control module, a speed and torque output control module, a PCI communication module and a torque limiter. Control module; the motion controller module includes enabling terminal control, trajectory planning processing, and feedback position processing; the multi-axis synchronous control method includes a high-speed synchronous drive stage and a pressurized bending drive stage;

1) Set the parameters through the embedded touch screen;

2) Enter the bending data for a specific workpiece through the embedded touch screen, and the industrial computer will automatically calculate the bending stroke, angle and deflection compensation, and generate the bending program;

3) When bending, place the sheet to be bent on the lower table of the all-electric bending machine, and the numerical control system drives the positioning of the back gauge device of the all-electric bending machine; at this time, the multi-axis synchronous control system is at high speed Synchronous drive stage; wherein, the first servo driver and the fourth servo driver are set to the speed control mode; the second servo driver and the third servo driver are set to the torque control mode, and the second servo driver drives the second permanent magnet synchronous servo motor to follow the torque The torque of the first permanent magnet synchronous servo motor, the torque of the third permanent magnet synchronous servo motor driven by the third servo driver follows the torque of the fourth permanent magnet synchronous servo motor; at the same time, the torque limiting control module converts the output torque of the four permanent magnet synchronous servo motors Adjust to a given value, and the torque change curve is a linear change;

4) The slider of the all-electric bending machine drives its upper mold down to the speed conversion point at a speed of 10-100mm/s, and then down to the clamping point at a speed of 1-10mm/s; at this time, the multi-axis synchronous control The system is switched to the pressure bending drive stage; the four servo drivers are all set to the speed control mode, and the torque limiting control module linearly adjusts the output torque of the four permanent magnet synchronous servo motors to a given pressure torque, and then Press and bend to the end of the stroke and hold the pressure;

5) After the pressure holding time is up, the torque limiting control module controls the four servo drives to automatically unload the pressure at the same time by reducing the torque output value, and the multi-axis synchronous control system switches to the high-speed synchronous drive stage and controls the slider of the all-electric bending machine High-speed upward return stroke, take away the forming sheet, and the processing is completed.

Preferably, the high-speed synchronous drive stage includes the steps of:

(1) The motion control module plans the motion trajectory of each axis according to the user's command, and converts it into a position command and sends it to the PID module. The PID module processes the input command according to its own proportional, integral and differential parameters, and then outputs the first speed command value ;

(2) The speed command is directly sent to the speed control board through the PCI communication module. The speed control board converts it into an analog voltage and transmits it to the first servo driver and the fourth servo driver through the cable. The first servo driver drives the first permanent The magnetic synchronous servo motor, the fourth servo driver drives the fourth permanent magnet synchronous servo motor to run at a given speed, and the sliders are driven by the first ball screw and the fourth ball screw to move up and down linearly;

(3) The first grating ruler, the second grating ruler, the third grating ruler and the fourth grating ruler respectively detect the mechanical position of the slider of the bending machine in real time, convert it into a level signal and transmit it to the speed control board, and the speed control board will After the electrical signal is converted into the first digital quantity, it is fed back to the PID module through the PCI communication module; the PID module compares the first digital quantity with the first output speed command value to obtain a position deviation, and the position deviation is adjusted by proportional and integral to generate a new speed command, and control the speed of the first permanent magnet synchronous servo motor and the fourth permanent magnet synchronous servo motor through step (2);

(4) Set the speed and torque output control module to the torque output mode. The speed control board collects the torque signals output by the first permanent magnet synchronous servo motor and the fourth permanent magnet synchronous servo motor in real time, and transmits them to the speed and torque through the PCI communication module. Torque output control module; After the torque signal is smoothed and filtered by the PCI communication module, it is sent to the speed control board by the PCI communication module, and sent to the second servo drive and the third servo drive respectively through the cable. The torque of the second permanent magnet synchronous servo motor driven by the servo drive follows the torque of the first permanent magnet synchronous servo motor through the second ball screw, and the torque of the third servo driver drives the third permanent magnet synchronous servo motor through the third ball screw to follow the torque of the fourth permanent magnet synchronous servo motor. Magnetic synchronous servo motor torque;

(5) The fuzzy control module makes a difference between the speed feedback of one of the permanent magnet synchronous servo motors and the speed feedback of the other three permanent magnet synchronous servo motors, and then determines the speed compensation amount according to the ratio of the moment of inertia of each permanent magnet synchronous servo motor; And use the position compensation amount and its rate of change as a reference to adjust the parameters of the PID controller for each axis online;

(6) The operation control module switches the working modes of the speed and torque output control module and the fuzzy control module through its switching control port output logic low level, and realizes switching from the high-speed synchronous driving stage to the pressure bending driving stage.

Preferably, the pressure bending driving stage includes the following steps:

(1) The motion control module plans the motion trajectory of each axis according to the user's command, and converts it into a position command and sends it to the PID module. The PID module processes the input command according to its own proportional, integral and differential parameters, and then outputs the second speed command value ;

(2) The speed command is directly sent to the speed control board through the PCI communication module, and the speed control board converts it into an analog voltage and transmits it to the first servo driver and the fourth servo driver through the cable; the first servo driver drives the first permanent The magnetic synchronous servo motor and the fourth servo driver drive the fourth permanent magnet synchronous servo motor to run at a given speed, and the sliders are driven by the first ball screw and the fourth ball screw to move up and down linearly;

(3) The first grating ruler, the second grating ruler, the third grating ruler and the fourth grating ruler respectively detect the mechanical position of the slider of the automatic bending machine in real time, convert it into a level signal and transmit it to the speed control board; speed control The board converts the electrical signal into the second digital quantity, and then feeds it back to the PID module through the PCI communication module. The PID module adjusts the second digital quantity, and the PID module compares the second digital quantity with the second output speed command value to obtain the position Deviation, the position deviation generates a new speed command after proportional and integral adjustment, and controls the speed of the first permanent magnet synchronous servo motor and the fourth permanent magnet synchronous servo motor through step (2);

(4) Set the speed and torque output control module in the speed output mode, the output speed commands of the second servo driver and the third servo driver are transferred to the speed and torque output control module, and the second servo driver drives the second permanent magnet synchronous servo motor , The third servo driver drives the third permanent magnet synchronous servo motor to run at a given speed, and the sliders are driven by the second ball screw and the third ball screw to move up and down linearly;

(5) The fuzzy control module fixedly outputs the parameters of the preset PID module;

(6) The operation control module switches the working mode of the speed and torque output control module and the fuzzy control module through its switching control port to output logic high level, so as to realize the switching from the pressure bending drive stage to the high-speed synchronous drive stage.

Preferably, the embedded touch screen collects bending-related parameter information input by the user, and the collected parameter information includes: target bending angle, bending speed, mold information, workpiece material parameters, slider deflection deformation compensation, and parallelism; After the user sets the parameters, the deflection deformation compensation and parallelism of the slider realize the control of the positions of the first ball screw, the second ball screw, the third ball screw and the fourth ball screw through the motion control module; The above servo synchronous control system can also realize the dynamic setting of the bending pressure of the slider by inputting pressure parameters on the embedded touch screen by the user;

The multi-axis synchronous control system also includes a positive and negative travel limit switch, and the switching value control board monitors the positive and negative travel limit switch states of the slider in real time; when the slider touches the positive and negative travel limit switch, the switching value controls The board card sends a trigger signal to the motion control module through the PCI communication module, and the motion control module stops the first permanent magnet synchronous servo motor, the second permanent magnet synchronous servo motor, the third permanent magnet synchronous servo motor, and the fourth permanent magnet synchronous servo motor. sports.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The multi-axis synchronous control system used in the all-electric bending machine of the present invention has a novel and ingenious structure, is clear and reasonable, and is easy to maintain; the system can significantly improve the synchronization performance of the operation of multiple permanent magnet synchronous servo motors and the bending positioning accuracy , and greatly reduces the wear of the ball screw and linear guide caused by the asynchronous permanent magnet synchronous servo motor, effectively increasing the service life of the bending machine transmission mechanism;

(2) The multi-axis synchronous control system for the slider of the all-electric bending machine of the present invention adopts the control system. When the bending machine does not move, the permanent magnet synchronous servo motor is in a static state, which can save energy to the greatest extent. energy;

(3) Generally speaking, when bending, the frame of the automatic bending machine will be deformed due to the force; since the system uses each ball screw in the press bending section to accurately control the position independently according to its own control law , according to different pressurized pressures, calculate the required amount of top frame deformation compensation, and superimpose it on the position instructions of the two ball screws in the middle to compensate the top frame deformation, so as to facilitate the intelligent automatic compensation of slider deflection;

(4) The system is easy to adjust, and the operator only needs to edit the parameters on the touch screen to complete a series of machine tool adjustments, thus greatly reducing the requirements for the operator's technical proficiency.

Description of drawings

Fig. 1 is the overall schematic diagram of control system of the present invention;

Fig. 2 is a schematic diagram of functional modules of the multi-axis synchronous control system of the present invention;

Fig. 3 is a schematic structural diagram of the single-axis control subsystem of the present invention;

Fig. 4 is a structural block diagram of the multi-axis synchronous control system of the present invention;

Fig. 5 is a block diagram of the hardware abstraction layer of the multi-axis synchronous control system of the present invention;

Fig. 6 is a working flowchart of the multi-axis synchronous control system of the present invention.

Detailed ways

The purpose of the invention of the present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments, and the embodiments cannot be repeated here one by one, but the implementation of the present invention is not therefore limited to the following embodiments. Unless otherwise specified, the materials and processing methods used in the present invention are conventional materials and processing methods in the technical field. the

As shown in Figure 1, the multi-axis synchronous control system for all-electric bending machines of the present invention includes a motion control board 1, a numerical control system 2 and four sets of slider drive mechanisms (3, 4, 5 and 6). Each set of slider driving mechanism includes a servo driver, a permanent magnet synchronous servo motor, a synchronous belt transmission mechanism, a ball screw and a grating ruler. the

Wherein, the four sets of slider driving mechanisms are respectively the first slider driving mechanism, the second slider driving mechanism, the third slider driving mechanism and the fourth slider driving mechanism. the

The first slider driving mechanism includes a first servo driver 31 , a first permanent magnet synchronous servo motor 32 , a first synchronous belt transmission mechanism 33 , a first ball screw 34 and a first grating scale 35 . The first permanent magnet synchronous servo motor 32 is connected to the first ball screw 34 through the first synchronous belt transmission mechanism 33, and the bottom end of the first ball screw 34 is installed on the top of the bending machine slider. The first grating ruler 35 is installed on the back of the bending machine slider and is on the same vertical axis as the first ball screw 34 . The first permanent magnet synchronous servo motor 32 is also connected to the first servo driver 31 , and the first servo driver 31 and the first grating scale 35 are respectively connected to the numerical control system 2 through the motion control board 1 . The first servo driver 31 , the first permanent magnet synchronous servo motor 32 , the first synchronous belt transmission mechanism 33 and the first ball screw 34 constitute a first servo system 30 . the

The second slider driving mechanism includes a second servo driver 41 , a second permanent magnet synchronous servo motor 42 , a second synchronous belt transmission mechanism 43 , a second ball screw 44 and a second grating scale 45 . The second permanent magnet synchronous servo motor 41 is connected with the second ball screw 44 through the second synchronous belt transmission mechanism 43, and the bottom end of the second ball screw 44 is installed on the top of the bending machine slider. The second grating ruler 45 is installed on the back of the bending machine slider and is on the same vertical axis as the second ball screw 44 . The second permanent magnet synchronous servo motor 42 is also connected to the second servo driver 41 , and the second servo driver 41 and the second grating ruler 45 are respectively connected to the numerical control system 2 through the motion control board 1 . The second servo driver 41 , the second permanent magnet synchronous servo motor 42 , the second synchronous belt transmission mechanism 43 and the second ball screw 44 constitute the second servo system 40 . the

The third slider driving mechanism includes a third servo driver 51 , a third permanent magnet synchronous servo motor 52 , a third synchronous belt transmission mechanism 53 , a third ball screw 54 and a third grating scale 55 . The third permanent magnet synchronous servo motor 52 is connected with the third ball screw 54 through the third synchronous belt transmission mechanism 53 , and the bottom end of the third ball screw 54 is installed on the top of the bending machine slider 8 . The third grating ruler 55 is installed on the back side of the bending machine slider 8 and is on the same vertical axis as the third ball screw 54 . The third permanent magnet synchronous servo motor 52 is also connected to the third servo driver 51 , and the third servo driver 51 and the third grating ruler 55 are respectively connected to the numerical control system 2 through the motion control board 1 . The third servo driver 51 , the third permanent magnet synchronous servo motor 52 , the third synchronous belt transmission mechanism 53 and the third ball screw 54 constitute the third servo system 50 . the

The fourth slider driving mechanism includes a fourth servo driver 61 , a fourth permanent magnet synchronous servo motor 62 , a fourth synchronous belt transmission mechanism 63 , a fourth ball screw 64 and a fourth grating scale 65 . The fourth permanent magnet synchronous servo motor 62 is connected with the fourth ball screw 64 through the fourth synchronous belt transmission mechanism 63, and the bottom end of the fourth ball screw 64 is installed on the top of the bending machine slider. The fourth grating ruler 65 is installed on the back of the bending machine slider and is on the same vertical axis as the fourth ball screw 64 . The fourth permanent magnet synchronous servo motor 62 is also connected to the fourth servo driver 61 , and the fourth servo driver 61 and the fourth grating ruler 65 are respectively connected to the numerical control system 2 through the motion control board 1 . The fourth servo driver 61 , the fourth permanent magnet synchronous servo motor 62 , the fourth synchronous belt transmission mechanism 63 and the fourth ball screw 64 constitute the fourth servo system 60 . the

As shown in FIG. 2 , the motion control board 1 includes a switch control board 11 and a speed control board 12 . The Rx port of the optical fiber module of the speed control board 11 is connected to the Tx port of the internal PCI module of the industrial control computer 21 through the optical fiber 7 . This x port also links to each other with the optical fiber module Rx end of switch control board 11, and the optical fiber module Tx port of switch control board 11 links to each other with the Rx port of the internal PCI module card of industrial control computer. the

As shown in Figure 3, the three-phase outputs U, V, W, and PE of the four servo drives are respectively connected to the power supply sides of the four permanent magnet synchronous servo motors. The X2 function ports of the four servo drives are respectively connected to the DB9 connectors of the speed control board 12 through 9-core cables. Wherein, the analog input port ISA00 is connected to the speed command output end of the speed control board 12 ; the analog input port ISA01 is connected to the torque control command output end of the speed control board 12 . In addition, the servo on signal, servo alarm signal and servo clear alarm signal of the four servo drivers are respectively connected to SRV_ON, ALM, SRV_CLR of the speed control card 12 . the

In addition, the encoder input ports of the four servo drives are respectively connected to the encoder output ends of the corresponding permanent magnet synchronous servo motors through cables. The brake control ports of the four servo drives are respectively connected to both ends of the relay coil. The brake input ports of the four permanent magnet synchronous servo motors are connected to the normally open switches of the relays. the

The multi-axis synchronous control system of the present invention is divided into four sets of slider drive mechanisms controlled by single-axis full-closed-loop synchronous subsystems. It adopts the equivalent velocity and acceleration compound feedforward controller to realize the rapid and accurate tracking of the given position signal, and adopts the two-dimensional fuzzy PID control algorithm to improve the synchronization accuracy of the four permanent magnet synchronous servo motors. The corresponding control methods are all programmed in the industrial control computer. the

As shown in Figure 4, set the first servo driver and the fourth servo driver to the speed output mode, and realize fast positioning under the action of the position loop PID module. Set the second servo driver and the third servo driver to torque output mode. The second servo driver drives the second permanent magnet synchronous servo motor torque to follow the first permanent magnet synchronous servo motor torque through the second ball screw, and the third servo driver drives the third permanent magnet synchronous servo motor torque to follow the first permanent magnet synchronous servo motor through the third ball screw Four permanent magnet synchronous servo motor torque. The control method is realized by programming inside the industrial control computer. the

As shown in FIG. 5 , the numerical control system 2 includes an industrial computer 21 and an embedded touch screen 22 . The industrial control computer 21 includes a motion control module, a PID module, a fuzzy control module, a speed and torque output control module, a PCI communication module and a torque limiting control module. Motion control module, PID module, and fuzzy control module realize the control of motion trajectory planning. The speed and torque output control module realizes the switching control of the system's high-speed synchronous drive structure and press bending structure. The torque limiting control module realizes the control of torque output. The speed control board 12 realizes the information exchange between four sets of servo systems ( 30 , 40 , 50 and 60 ) and the industrial computer 21 . All modules are realized by programming in C language inside the industrial control computer. the

As shown in Figure 6, the bending process is operated as shown in the figure to complete the processing of each bending node. The bending angle of the plate is mainly realized by controlling the displacement of the upper die in the groove of the lower die through four sets of servo systems (30, 40, 50 and 60). In actual operation, the user completes the setting of all parameters, inputs the bending data for a specific workpiece, and the CNC system will calculate the bending stroke, angle and deflection compensation by the industrial control, and generate the bending program. the

When bending, place the sheet to be bent on the lower table of the all-electric bending machine, and the numerical control system drives the positioning of the back gauge device of the all-electric bending machine; at this time, the multi-axis synchronous control system is a high-speed synchronous drive stage; wherein, the first servo driver and the fourth servo driver are set to the speed control mode; the second servo driver and the third servo driver are set to the torque control mode, and the second servo driver drives the second permanent magnet synchronous servo motor torque to follow the first Permanent magnet synchronous servo motor torque, the third servo driver drives the third permanent magnet synchronous servo motor torque to follow the fourth permanent magnet synchronous servo motor torque; at the same time, the torque limiting control module adjusts the output torque of the four permanent magnet synchronous servo motors to Given value, and the torque change curve is a linear change;

The slider of the all-electric bending machine drives its upper mold down from the top dead center to the speed conversion point at high speed, and then down to the clamping point at a slow speed; at this time, the multi-axis synchronous control system switches to the pressure bending drive stage ; The four servo drivers are all set to the speed control mode, and the torque limiting control module linearly adjusts the output torque of the four permanent magnet synchronous servo motors to a given pressure torque, and then presses and bends to the end of the stroke and performs hold pressure;

After the pressure holding time is up, the pressure will be relieved automatically, the multi-axis synchronous control system will switch to the high-speed synchronous drive stage and control the slider of the all-electric bending machine to return at high speed to remove the formed sheet, and the processing is completed.

At present, my country has made some achievements in the research and development of hydraulic bending machines of various tonnages, but it still lags behind foreign manufacturers in terms of higher-level numerical control systems, and lacks a bending machine numerical control system that can be practical and put on the market. In the case that developed countries such as Europe, America and Japan have implemented barriers and blockade policies against my country in key technologies of major equipment, in order to break the monopoly position of foreign countries in this technology and ensure the growth and sustainable development of the national economy, it is urgent to develop independent Intellectual property of advanced manufacturing technology. The all-electric bending machine of the present invention is a representative of advanced sheet metal processing equipment, and its research and development has high technical and social economic significance. the

The above embodiments are only preferred embodiments of the present invention, and are not intended to limit the implementation scope of the present invention. That is, all equivalent changes and modifications made according to the content of the present invention are covered by the protection scope of the claims of the present invention. the

Claims (10)

1. A multi-axis synchronous control system for an all-electric bending machine, characterized in that: it includes a motion control board, a numerical control system, and several sets of slider drive mechanisms; each set of slider drive mechanisms includes a servo driver, a permanent magnet Synchronous servo motor, synchronous belt transmission mechanism, ball screw and grating scale; the permanent magnet synchronous servo motor is connected with the ball screw through the synchronous belt transmission mechanism, and the bottom end of the ball screw is installed on the top of the bending machine slider ; The grating ruler is installed on the back of the bending machine slider and on the same vertical axis as the ball screw; the permanent magnet synchronous servo motor is also connected to the servo driver, and the servo driver and the grating ruler are respectively passed through the motion control board Connected with CNC system. 2. The multi-axis synchronous control system for all-electric bending machines according to claim 1, characterized in that: the three-phase output of the servo driver is connected to the power supply side of the servo motor; The X2 function port is connected to the motion control board through a cable, and the encoder input port of the servo driver is connected to the rotary encoder output end of the permanent magnet synchronous servo motor through a cable. 3. The multi-axis synchronous control system for all-electric bending machine according to claim 1, characterized in that: the numerical control system includes an industrial computer and an embedded touch screen; the embedded touch screen is connected to the industrial computer; The motion control board includes a switch control board and a speed control board; the servo drive and the grating ruler are connected to the speed control board, and the switch control board is connected to the positive and negative sides of the slider of the bending machine through a cable. Stroke limit switch; the switching value control board and the speed control board are connected to the PCI module inside the industrial control computer through optical fiber. 4. The multi-axis synchronous control system for all-electric bending machine according to claim 1, characterized in that: the synchronous belt transmission mechanism includes a first belt gear, a synchronous belt and a second belt gear; the first belt The gear is installed on the output shaft of the permanent magnet synchronous servo motor, the second belt gear is installed on the nut of the ball screw, and the second belt gear is connected with the first belt gear through a synchronous belt. 5. The multi-axis synchronous control system for an all-electric bending machine according to claim 1, wherein the length of the slider of the bending machine is greater than 3000mm. 6. The multi-axis synchronous control system for an all-electric bending machine according to any one of claims 1-5, characterized in that: the number of the slider driving mechanisms is four groups, each of which is the first slider The driving mechanism, the second slider driving mechanism, the third slider driving mechanism and the fourth slider driving mechanism; the first slider driving mechanism includes a first servo driver, a first permanent magnet synchronous servo motor, and a first synchronous belt transmission mechanism , the first ball screw and the first grating scale; the second slider driving mechanism includes a second servo driver, a second permanent magnet synchronous servo motor, a second synchronous belt transmission mechanism, a second ball screw and a second grating scale; The third slider driving mechanism includes a third servo driver, a third permanent magnet synchronous servo motor, a third synchronous belt transmission mechanism, a third ball screw and a third grating ruler; the fourth slider driving mechanism includes a fourth servo driver, The fourth permanent magnet synchronous servo motor, the fourth synchronous belt transmission mechanism, the fourth ball screw and the fourth grating ruler. 7. A multi-axis synchronous control method for an all-electric bending machine as claimed in claim 6: it is characterized in that: the industrial control computer includes a motion control module, a PID module, a fuzzy control module, a speed and torque output control module, PCI communication module and torque limiting control module; the motion controller module includes enabling terminal control, trajectory planning processing and feedback position processing; the multi-axis synchronous control method includes a high-speed synchronous driving stage and a pressure bending driving stage; 1) Set the parameters through the embedded touch screen; 2) Enter the bending data for a specific workpiece through the embedded touch screen, and the industrial computer will automatically calculate the bending stroke, angle and deflection compensation, and generate the bending program; 3) When bending, place the sheet to be bent on the lower table of the all-electric bending machine, and the numerical control system drives the positioning of the back gauge device of the all-electric bending machine; at this time, the multi-axis synchronous control system is at high speed Synchronous drive stage; wherein, the first servo driver and the fourth servo driver are set to the speed control mode; the second servo driver and the third servo driver are set to the torque control mode, and the second servo driver drives the second permanent magnet synchronous servo motor to follow the torque The torque of the first permanent magnet synchronous servo motor, the torque of the third permanent magnet synchronous servo motor driven by the third servo driver follows the torque of the fourth permanent magnet synchronous servo motor; at the same time, the torque limiting control module converts the output torque of the four permanent magnet synchronous servo motors Adjust to a given value, and the torque change curve is a linear change; 4) The slider of the all-electric bending machine drives its upper mold down to the speed conversion point at a speed of 10-100mm/s, and then down to the clamping point at a speed of 1-10mm/s; at this time, the multi-axis synchronous control The system is switched to the pressure bending drive stage; the four servo drivers are all set to the speed control mode, and the torque limiting control module linearly adjusts the output torque of the four permanent magnet synchronous servo motors to a given pressure torque, and then Press and bend to the end of the stroke and hold the pressure; 5) After the pressure holding time is up, the torque limiting control module controls the four servo drives to automatically unload the pressure at the same time by reducing the torque output value, and the multi-axis synchronous control system switches to the high-speed synchronous drive stage and controls the slider of the all-electric bending machine High-speed upward return stroke, take away the forming sheet, and the processing is completed. 8. The control method according to claim 7, characterized in that: the high-speed synchronous driving stage comprises the following steps: (1) The motion control module plans the motion trajectory of each axis according to the user's command, and converts it into a position command and sends it to the PID module. The PID module processes the input command according to its own proportional, integral and differential parameters, and then outputs the first speed command value ; (2) The speed command is directly sent to the speed control board through the PCI communication module. The speed control board converts it into an analog voltage and transmits it to the first servo driver and the fourth servo driver through the cable. The first servo driver drives the first permanent The magnetic synchronous servo motor, the fourth servo driver drives the fourth permanent magnet synchronous servo motor to run at a given speed, and the sliders are driven by the first ball screw and the fourth ball screw to move up and down linearly; (3) The first grating ruler, the second grating ruler, the third grating ruler and the fourth grating ruler respectively detect the mechanical position of the slider of the bending machine in real time, convert it into a level signal and transmit it to the speed control board, and the speed control board will After the electrical signal is converted into the first digital quantity, it is fed back to the PID module through the PCI communication module; the PID module compares the first digital quantity with the first output speed command value to obtain a position deviation, and the position deviation is adjusted by proportional and integral to generate a new speed command, and control the speed of the first permanent magnet synchronous servo motor and the fourth permanent magnet synchronous servo motor through step (2); (4) Set the speed and torque output control module to the torque output mode. The speed control board collects the torque signals output by the first permanent magnet synchronous servo motor and the fourth permanent magnet synchronous servo motor in real time, and transmits them to the speed and torque through the PCI communication module. Torque output control module; After the torque signal is smoothed and filtered by the PCI communication module, it is sent to the speed control board by the PCI communication module, and sent to the second servo drive and the third servo drive respectively through the cable. The torque of the second permanent magnet synchronous servo motor driven by the servo drive follows the torque of the first permanent magnet synchronous servo motor through the second ball screw, and the torque of the third servo driver drives the third permanent magnet synchronous servo motor through the third ball screw to follow the torque of the fourth permanent magnet synchronous servo motor. Magnetic synchronous servo motor torque; (5) The fuzzy control module makes a difference between the speed feedback of one of the permanent magnet synchronous servo motors and the speed feedback of the other three permanent magnet synchronous servo motors, and then determines the speed compensation amount according to the ratio of the moment of inertia of each permanent magnet synchronous servo motor; And use the position compensation amount and its rate of change as a reference to adjust the parameters of the PID controller for each axis online; (6) The operation control module switches the working modes of the speed and torque output control module and the fuzzy control module through its switching control port output logic low level, and realizes switching from the high-speed synchronous driving stage to the pressure bending driving stage. 9. The control method according to claim 8, characterized in that: the pressure bending driving stage comprises the following steps: (1) The motion control module plans the motion trajectory of each axis according to the user's command, and converts it into a position command and sends it to the PID module. The PID module processes the input command according to its own proportional, integral and differential parameters, and then outputs the second speed command value ; (2) The speed command is directly sent to the speed control board through the PCI communication module, and the speed control board converts it into an analog voltage and transmits it to the first servo driver and the fourth servo driver through the cable; the first servo driver drives the first permanent The magnetic synchronous servo motor and the fourth servo driver drive the fourth permanent magnet synchronous servo motor to run at a given speed, and the sliders are driven by the first ball screw and the fourth ball screw to move up and down linearly; (3) The first grating ruler, the second grating ruler, the third grating ruler and the fourth grating ruler respectively detect the mechanical position of the slider of the automatic bending machine in real time, convert it into a level signal and transmit it to the speed control board; speed control The board converts the electrical signal into the second digital quantity, and then feeds it back to the PID module through the PCI communication module. The PID module adjusts the second digital quantity, and the PID module compares the second digital quantity with the second output speed command value to obtain the position Deviation, the position deviation generates a new speed command after proportional and integral adjustment, and controls the speed of the first permanent magnet synchronous servo motor and the fourth permanent magnet synchronous servo motor through step (2); (4) Set the speed and torque output control module in the speed output mode, the output speed commands of the second servo driver and the third servo driver are transferred to the speed and torque output control module, and the second servo driver drives the second permanent magnet synchronous servo motor , The third servo driver drives the third permanent magnet synchronous servo motor to run at a given speed, and the sliders are driven by the second ball screw and the third ball screw to move up and down linearly; (5) The fuzzy control module fixedly outputs the parameters of the preset PID module; (6) The operation control module switches the working mode of the speed and torque output control module and the fuzzy control module through its switching control port to output logic high level, so as to realize the switching from the pressure bending drive stage to the high-speed synchronous drive stage. 10. The control method according to claim 8, characterized in that: the embedded touch screen collects bending-related parameter information input by the user, and the collected parameter information includes: target bending angle, bending speed, mold information, Workpiece material parameters, slider deflection and deformation compensation and parallelism; after the user sets the parameters, the slider deflection and deformation compensation and parallelism are realized through the motion control module for the first ball screw, the second ball screw, and the third ball screw. The control of the position of the lead screw and the fourth ball screw; the servo synchronous control system can also realize the dynamic setting of the bending pressure of the slider by inputting pressure parameters on the embedded touch screen by the user; The multi-axis synchronous control system also includes a positive and negative travel limit switch, and the switching value control board monitors the positive and negative travel limit switch states of the slider in real time; when the slider touches the positive and negative travel limit switch, the switching value controls The board card sends a trigger signal to the motion control module through the PCI communication module, and the motion control module stops the first permanent magnet synchronous servo motor, the second permanent magnet synchronous servo motor, the third permanent magnet synchronous servo motor, and the fourth permanent magnet synchronous servo motor. sports.

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