A method for bending a wiper steel bar

Abstract

A method for bending a steel bar of a windshield wiper, wherein the device realizes the bending operation of the steel bar by setting a cam mechanism 1, and at the same time, a cam mechanism 2 is set between the cam mechanism 1 and the mid-position cutting servo, and the bending stress generated by the steel bar passing through the cam mechanism 1 is eliminated by means of the movement of the cam mechanism 2; the mid-position cutting servo is set in the mid-position cutting transmission device, and the steel bar cutting servo is set in the steel bar cutting transmission device, and the mid-position cutting servo and the steel bar cutting servo can respectively operate on the transmission track 1 of the mid-position cutting transmission device and the transmission track 2 of the steel bar cutting transmission device to control the cutting point and the cutting point, thereby facilitating the control of the cutting length of the steel bar, and on the other hand, it can also reduce the shaking of the steel bar during cutting or cutting, thereby ensuring the accuracy of the cutting and cutting positions of the steel bar.

Description

Technical Field

[0001] The invention relates to the field of automobile accessories, in particular to a method for bending a wiper steel bar. Background Art

[0002] Since the front and rear windshields of the car have a certain curvature, the wipers set on the front and rear windshields also need to match the curvature of the glass. At present, steel bar bending machines are usually used to complete the bending operation of the steel bars on the wipers; on the other hand, since the size, bending curve and stress of the wipers corresponding to each car are different, the bending curve of the steel bar needs to be adapted according to the curvature of the front and rear windshields of each model, so the steel bar bending machine must take into account the general performance, among which the traditional steel bar bending machine can basically meet the requirements of general performance. Traditional steel bar bending machines include two categories: domestic and imported. Among them, domestic bending machines have a single function, poor precision, and the performance of the products produced is unstable. After long-term use, the products are prone to deformation; in contrast, imported bending machines have complex structures and high precision, and the performance of the products produced is more stable, but imported bending machines are expensive, which has caused a great burden on small and medium-sized enterprises. Therefore, a wiper steel bar bending equipment with high precision, simple structure and low cost is needed. Summary of the invention

[0003] The purpose of the present invention is to solve the deficiencies of the prior art and provide a method for bending a wiper steel bar, which has a simple structure and is easy to use.

[0004] A windshield wiper steel bar bending equipment, including a main control system, a steel bar unwinding mechanism, a transmission servo, a bending servo, a stress relief servo, a center cutting servo, a steel bar cutting servo, a center cutting transmission device and a steel bar cutting transmission device; wherein the center cutting servo is arranged in the center cutting transmission device, and the steel bar cutting servo is arranged in the steel bar cutting transmission device; the transmission servo is located between the steel bar unwinding mechanism and the bending servo; the stress relief servo is located between the bending servo and the center cutting servo; the center cutting servo is located between the stress relief servo and the steel bar cutting servo; the main control system is respectively communicated with the steel bar unwinding mechanism, the transmission servo, the bending servo, the stress relief servo, the center cutting servo, the steel bar cutting servo, the center cutting transmission servo and the steel bar cutting transmission servo.

[0005] Furthermore, the main control system includes a motion controller and a touch screen, wherein the motion controller is used to control the rotation direction and rotation speed of the servo motor; the touch screen serves as an HMI human-machine interface;

[0006] The steel bar unwinding mechanism comprises a steel bar unwinding motor and an unwinding detection sensor, wherein the unwinding detection sensor can detect the transmission speed of the steel bar, and the rotation speed of the unwinding motor is adjusted according to the processing speed of the steel bar;

[0007] The transmission servo is used to transmit the steel bar to the working area of ​​the bending servo, wherein the transmission path is a linear transmission; the transmission servo is an EtherCat bus servo;

[0008] The bending servo is an EtherCat bus servo, and the bending servo adopts an absolute value servo motor as a drive. The bending servo also includes a cam mechanism 1, wherein the cam mechanism 1 simulates the cam motion trajectory curve control to achieve the bending operation of the steel bar;

[0009] The stress relief servo is an EtherCat bus servo, the stress relief servo adopts an absolute value servo motor as a drive, and the stress relief servo also includes a cam mechanism 2, wherein the cam mechanism 2 simulates the cam motion trajectory curve control;

[0010] The middle cutting servo is an EtherCat bus servo, and the middle cutting servo is used to cut the installation hole position in the middle part of the steel bar;

[0011] The mid-position cutting transmission device includes a mid-position cutting transmission servo and a transmission track 1, and the mid-position cutting servo is arranged on the transmission track 1; the steel bar cutting transmission device includes a steel bar cutting transmission servo and a transmission track 2, and the steel bar cutting servo is arranged on the transmission track 2.

[0012] Furthermore, the transmission servo includes at least two groups of transmission wheels, each group of transmission wheels includes two transmission wheels; the two transmission wheels in the same group of transmission wheels are symmetrically arranged about the steel bar; and the line connecting the axes of the transmission wheels located on the same side of the steel bar is parallel to the steel bar.

[0013] Furthermore, it also includes an origin detection sensor, which is a zero position detection switch; the origin detection sensor is respectively arranged at the middle cutting servo and the steel bar cutting servo, and is used to provide positioning detection for the middle cutting servo and the steel bar cutting servo.

[0014] A method for bending a wiper steel bar comprises the following steps:

[0015] Step 1: The motion controller downloads the processing formula of the steel bar according to the input of the HMI human-machine interface;

[0016] Step 2: The motion controller adjusts the processing formula according to the input of the HMI human-machine interface, including the adjustment of the steel bar data and the fitting adjustment of the electronic cam parameters; the steel bar data includes the cutoff length and the production quantity, and the electronic cam parameters include the curve offset, curve translation, data scaling and curve symmetry data; and sends the adjusted processing formula data;

[0017] Step 3: The motion controller controls the center cutting servo and the steel bar cutting servo to the specified position;

[0018] Step 4: The motion controller controls the steel bar unwinding mechanism and the transmission servo to start the action and continuously feed the steel bar;

[0019] Step 5: The motion controller controls the bending servo and the stress relief servo to perform linkage feeding according to the fitted and adjusted electronic cam parameters;

[0020] Step 6: After the length of the steel bar fed by the transmission servo reaches the cut-off length, the motion controller controls the middle cutting servo and the steel bar cut-off servo to move;

[0021] Step 7: The motion controller determines whether the production quantity of steel bars meets the input cutting quantity requirement; if it is less than the input production quantity, it returns to step 4; otherwise, it ends the step.

[0022] Furthermore, the input of the HMI human-machine interface in step 1 includes manual control options, parameter settings, curve settings, and curve recipe saving and downloading; wherein the manual control option is used to realize the inching control of each axis; the parameter setting is used to set the equipment parameters, including the operating speed of each servo; the curve setting includes two modes, long size and short size, and the long size and short size are determined according to the truncation length of the steel bar, and the data points of the long size mode are more than the data points of the short size mode; the saving and downloading of the curve recipe can save the optimal parameters for the corresponding steel bar production, and customize the name of the saved parameter file.

[0023] Furthermore, the fitting adjustment of the electronic cam parameters in step 2 includes the following steps:

[0024] Step 21: fitting the trajectory curve of the cam according to the set fitting conversion table;

[0025] Step 22: Perform symmetry correction on the fitted cam curve, and set the curve setting of the first half to achieve symmetric setting of the first half and the second half through the curve symmetry function;

[0026] Step 23: Cache and back up the curve data;

[0027] Step 24: performing a curve translation operation on the curve data that has completed symmetry correction in step 22;

[0028] Step 25: Perform a curve scaling operation on the curve data that has completed translation, vertically zoom in or out the motion trajectory curve data of the simulated cam 1, obtain the motion trajectory curve data of the simulated cam 2, and realize the adjustment of the overall data;

[0029] Step 26: Re-establish the cam trajectory curve of the simulated cam 1, and establish the cam trajectory curve of the simulated cam 2 according to the offset.

[0030] Furthermore, in step 22, the fitting curve is symmetrically corrected to achieve symmetrical setting of the first half and the second half. The symmetrical correction formula of the cam track curve of the electronic cam is shown as follows:

[0031] If the cam track curve of the simulated cam is divided by X point data, where:

[0032] TF[(X-n+1)]=TF[n]M=0;n>=1;

[0033] TF[(X-n+1)]=TF[n+2M]M>0,M<=5;n>=2;

[0034] TF[(X-n+1)+2M]=TF[n]M<0,M>=-5; n>=2;

[0035] Where n represents the number of curve points, TF[n] represents the vertical coordinate value corresponding to the nth curve point of the simulated cam 1; M represents the translation parameter.

[0036] Furthermore, the curve translation operation in step 24 is as shown in the following formula:

[0037] TF[n]=Copy_TF[nM]nM>0 and n>=2;

[0038] Wherein M represents the translation parameter; TF[n] is the ordinate value of the nth curve point after the symmetric correction in step 22; Copy_TF[nM] represents the cache backup array of the nMth point of the cache backup data of the simulated cam 1 in step 23.

[0039] Furthermore, in the step 26, the cam curve is re-established, and the relationship between the actual bending servo and the cam table fitting curve needs to be converted and converted; wherein the virtual stroke length of the spindle is set to Y, and the motion trajectory curve of the cam is divided by X point data, then the spindle feed corresponding to each curve point is expressed as P, P = Y / (XZ), Z represents the number of segments contained in the median segment of the motion trajectory curve of the cam; the scaling parameter K of the spindle is expressed as K = L / Y, L represents the steel bar cutoff length set in step 2; the spindle position is shown in the following formula:

[0040] ZD[n]=P*(n-1);

[0041]

[0042] ZD[n]=P*(nZ);

[0043] Where ZD[n] represents the horizontal coordinate corresponding to the nth curve point in the simulated cam track curve;

[0044] The simulated cam position is shown as follows:

[0045] CD[n]=TF[n];1<=n<=X;

[0046] Wherein CD[n] represents the position of the simulated cam 1 corresponding to the n-th curve point in the trajectory curve of the simulated cam 1; TF[n] represents the ordinate value corresponding to the n-th curve point of the simulated cam 1;

[0047] The linkage speed of the simulated cam 1 is shown as follows:

[0048] V[n]=(CD[n]-CD[n-1]) / P; and

[0049] V[n]=(CD[n]-CD[n-1]) / (P / Z);

[0050] V[1]=V[2]; n=1;

[0051] Where V[n] represents the velocity in the longitudinal direction at the nth curve point in the trajectory curve of the simulated cam 1;

[0052] Assume that the actual translation fine adjustment of the simulated cam 2 is E, and the converted translation fine adjustment is e, e = E / K, and the spindle position is as follows:

[0053] ZDX[n]=P*(n-1); 1<=n<=(1+2M);

[0054] ZDX[n]=P*(n-1)+e;

[0055]

[0056] ZDX[n]=P*(nZ)+e;

[0057] Where ZDX[n] represents the horizontal coordinate corresponding to the nth curve point in the trajectory curve of the simulated cam 2;

[0058] The analog cam second position is shown as follows:

[0059] CDX[n]=TW[n]+g; 1<=n<=X;

[0060] Wherein CDX[n] represents the position of the simulated cam 2 at the nth curve point in the trajectory curve of the simulated cam 2; TW[n] represents the ordinate value of the position of the nth curve point in the trajectory curve of the simulated cam 2; g represents the position offset between the simulated cam 1 and the simulated cam 2;

[0061] The linkage speed of the simulated cam 2 is shown in the following formula:

[0062] VX[n]=(CD[n]-CD[n-1]) / P; and

[0063] VX[n]=(CD[n]-CD[n-1]) / (P / Z);

[0064] VX[1]=VX[2];n=1;

[0065] Where VX[n] represents the velocity in the longitudinal direction when simulating the nth curve point of the second trajectory curve of the cam.

[0066] The beneficial effects of the present invention are:

[0067] The bending operation of the steel bar is realized by setting a cam mechanism 1, and a cam mechanism 2 is set between the cam mechanism 1 and the mid-position cutting servo, and the bending stress generated by the steel bar passing through the cam mechanism 1 is eliminated by means of the movement of the cam mechanism 2;

[0068] By setting the middle cutting servo in the middle cutting transmission device, and setting the steel bar cutting servo in the steel bar cutting transmission device, and the middle cutting servo and the steel bar cutting servo can respectively operate on the transmission track 1 of the middle cutting transmission device and the transmission track 2 of the steel bar cutting transmission device, the cutting point and the cutting point can be accurately controlled, thereby facilitating the control of the cutting length of the steel bar, and on the other hand, the shaking of the steel bar during cutting or cutting can be reduced, thereby ensuring the accuracy of the cutting and cutting positions of the steel bar;

[0069] By setting two simulated electronic cams, cam mechanism 1 and cam mechanism 2 are synchronously controlled to achieve stress relief operation of steel bar bending, thereby improving the stability and service life of the product. On the other hand, setting the electronic cam for simulation is convenient for debugging the machine and can improve the debugging efficiency of the product. By fitting and adjusting the electronic cam parameters, including symmetry correction, curve translation, and curve scaling, better steel bar bending effect can be achieved.

[0070] By setting the median line segment to include Z line segments, the position of the cam can be accurately controlled when the steel bar is bent and stress relieved through the inflection point. BRIEF DESCRIPTION OF THE DRAWINGS

[0071] Figure 1This is a schematic diagram of the position relationship connection of the device according to the first embodiment of the present invention;

[0072] Figure 2 This is a schematic diagram of device control relationship according to Embodiment 1 of the present invention;

[0073] Figure 3 It is a structural diagram of a bending servo and a stress relief servo according to the first embodiment of the present invention;

[0074] Figure 4 This is a flow chart of a method according to Embodiment 1 of the present invention;

[0075] Figure 5 is the cam trajectory curve fitted in step 21 of the first embodiment of the present invention;

[0076] Figure 6 The trajectory curve after symmetry correction in step 22 of the first embodiment of the present invention;

[0077] Figure 7 The trajectory curve before the curve is translated in step 24 of the first embodiment of the present invention;

[0078] Figure 8 It is the trajectory curve after the curve is translated in step 24 of the first embodiment of the present invention;

[0079] Fig. 9 The trajectory curve before the curve is scaled in step 25 of the first embodiment of the present invention;

[0080] Fig.10 It is the trajectory curve after the curve is scaled in step 25 of the first embodiment of the present invention.

[0081] Description of the accompanying drawings: transmission servo 1, bending servo 2, cam 1 21, pressure block 1 22, stress relief servo 3, cam 2 31, steel bar 4. DETAILED DESCRIPTION

[0082] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0083] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0084] Embodiment 1:

[0085] like Figure 1 , 2 As shown, a windshield wiper steel bar bending equipment includes a main control system, a steel bar unwinding mechanism, a transmission servo 1, a bending servo 2, a stress relief servo 3, a center cutting servo, a steel bar cutting servo, a center cutting transmission device, and a steel bar cutting transmission device. The center cutting servo is arranged in the center cutting transmission device, and the steel bar cutting servo is arranged in the steel bar cutting transmission device; the transmission servo is located between the steel bar unwinding mechanism and the bending servo; the stress relief servo is located between the bending servo and the center cutting servo; and the center cutting servo is located between the stress relief servo and the steel bar cutting servo. The main control system is respectively connected to the steel bar unwinding mechanism, the transmission servo, the bending servo, the stress relief servo, the center cutting servo, the steel bar cutting servo, the center cutting transmission servo, and the steel bar cutting transmission servo.

[0086] The main control system includes a motion controller and a touch screen, wherein the motion controller is used to control the rotation direction and rotation speed of the servo motor; the touch screen is used as an HMI human-machine interface to realize parameter setting, function control, steel bar bending curve adjustment, recipe storage and other functions. The motion controller and the steel bar unwinding mechanism are controlled by digital quantities; the motion controller and the HMI human-machine interface realize information exchange through Ethernet.

[0087] The steel bar unwinding mechanism includes a steel bar unwinding motor and an unwinding detection sensor, wherein the unwinding detection sensor can detect the transmission speed of the steel bar, and the rotation speed of the unwinding motor can be adjusted according to the processing speed of the steel bar to achieve the purpose of adaptively adapting to different production rhythms.

[0088] The transmission servo 1 is used to transmit the steel bar 4 to the working area of ​​the bending servo 2, wherein the transmission path is a straight line transmission. The transmission servo 1 is an EtherCat bus servo. The transmission servo 1 includes at least two sets of transmission wheels, each set of transmission wheels includes two transmission wheels; the two transmission wheels in the same set of transmission wheels are symmetrically arranged about the steel bar 4, and the connecting line of the transmission wheel axes on the same side of the steel bar is parallel to the steel bar. The purpose is to ensure that the steel bar passing through the transmission servo remains straight.

[0089] like Figure 3As shown, the bending servo 2 is an EtherCat bus servo, and the bending servo 2 adopts an absolute value servo motor as a drive. The bending servo also includes a cam mechanism 1, wherein the cam mechanism 1 is controlled by simulating the cam motion trajectory curve to complete the bending operation of the steel bar. The cam mechanism 1 includes a cam 21 and a pressure block 22, wherein the position of the pressure block 22 relative to the cam 21 can be adjusted; the steel bar 4 is located between the pressure block 22 and the cam 21. During the implementation process, the cam 21 presses the steel bar 4 toward the pressure block 22 to achieve the bending operation of the steel bar 4 passing through the cam 21 and the pressure block 22.

[0090] The stress relief servo 3 is an EtherCat bus servo. The stress relief servo 3 is driven by an absolute value servo motor. The stress relief servo also includes a cam mechanism 2, wherein the cam mechanism 2 is controlled by simulating the cam motion trajectory curve. After the steel bar is bent and formed by the bending servo, the bending stress is removed. The cam mechanism 2 includes a cam 2 31. The cam 2 moves along a set motion trajectory to squeeze the steel bar 4 to remove the bending stress. A roller is provided at the bottom of the cam 2 31. In this example, the roller contacts the protruding side of the steel bar 4 that has been bent, squeezes the steel bar 4, and releases the stress generated by the bending.

[0091] The center-cutting servo is an EtherCat bus servo, which is used to cut installation holes in the middle of the steel bar, where the installation holes are used to install and connect the steel bar with other components of the wiper.

[0092] The steel bar cutting servo is an EtherCat bus servo, and the steel bar cutting servo is used to implement the steel bar cutting operation.

[0093] The mid-position cutting transmission device includes a mid-position cutting transmission servo and a transmission track 1, wherein the mid-position cutting servo is arranged on the transmission track 1; the steel bar cutting transmission device includes a steel bar cutting transmission servo and a transmission track 2, wherein the steel bar cutting servo is arranged on the transmission track 2. In this example, the mid-position cutting servo can slide on the transmission track 1 with the action of the mid-position cutting transmission servo, and the steel bar cutting servo can slide on the transmission track 2 with the action of the steel bar cutting transmission servo. The mid-position cutting transmission servo and the steel bar cutting transmission servo both use absolute value servo motors.

[0094] It also includes an origin detection sensor, which is a zero position detection switch. In this example, the origin detection sensors are respectively arranged at the middle cutting servo and the steel bar cutting servo, and are used to provide positioning detection for the middle cutting servo and the steel bar cutting servo to achieve accurate cutting or cutting. The origin detection sensor and the motion controller of the main control system realize information transmission through digital quantity.

[0095] During the implementation process, the bending operation of the steel bar is realized by cam mechanism 1, and at the same time, a cam mechanism 2 is arranged between the cam mechanism 1 and the mid-position cutting servo, and the bending stress generated by the steel bar passing through the cam mechanism 1 is eliminated by the cam mechanism 2; the mid-position cutting servo is arranged in the mid-position cutting transmission device, and the steel bar cutting servo is arranged in the steel bar cutting transmission device, and the mid-position cutting servo and the steel bar cutting servo can respectively operate on the transmission track 1 of the mid-position cutting transmission device and the transmission track 2 of the steel bar cutting transmission device, so as to accurately control the cutting point and the cutting point, thereby facilitating the control of the cutting length of the steel bar, and on the other hand, it can also reduce the shaking of the steel bar during cutting or cutting, thereby ensuring the accuracy of the cutting and cutting positions of the steel bar.

[0096] like Figure 4 As shown, a method for bending a wiper steel bar comprises the following steps:

[0097] Step 1: The motion controller downloads the processing formula of the steel bar according to the input of the HMI human-machine interface;

[0098] Step 2: The motion controller adjusts the processing formula according to the input of the HMI human-machine interface, including the adjustment of the steel bar data and the fitting adjustment of the electronic cam parameters, where the steel bar data includes the cutoff length, production quantity, etc., and the electronic cam parameters include curve offset, curve translation, data scaling, curve symmetry, etc.; and sends the adjusted processing formula data;

[0099] Step 3: The motion controller controls the center cutting servo and the steel bar cutting servo to the specified position;

[0100] Step 4: The motion controller controls the steel bar unwinding mechanism and the transmission servo to start the action and continuously feed the steel bar;

[0101] Step 5: The motion controller controls the bending servo and the stress relief servo to perform linkage feeding according to the fitted and adjusted electronic cam parameters;

[0102] Step 6: After the length of the steel bar fed by the transmission servo reaches the cut-off length, the motion controller controls the middle cutting servo and the steel bar cut-off servo to move;

[0103] Step 7: The motion controller determines whether the production quantity of steel bars meets the input cutting quantity requirement; if it is less than the input production quantity, it returns to step 4; otherwise, it ends the step.

[0104] The input of the HMI human-machine interface in step 1 includes manual control options, parameter settings, curve settings, curve recipe saving and downloading, etc. The manual control option is used to realize the jog control (JOG) of each axis. When debugging the equipment, it is convenient to install and adjust the equipment by controlling the movement of each axis. The parameter setting is used to set the equipment parameters, including the running speed of each servo. The curve setting includes two modes: long size and short size. The long size and short size are determined according to the actual cut-off length of the steel bar; the long size mode has more data points than the short size mode, because the bending process of the long-size steel bar takes longer, so more data points need to be set to achieve precise control. In this example, the long-size mode decomposes the electronic cam curve simulation into 63 points of data. The electronic cam includes simulated cam 1 and simulated cam 2, which correspond to the simulated states of cam mechanism 1 and cam mechanism 2 respectively; the short-size mode decomposes the electronic cam trajectory curve simulation into 43 points of data; by dividing the cam motion trajectory curves of simulated cam 1 and simulated cam 2, compared with the conventional simple control of the cam motion distance, the cam mechanism is controlled according to the cam motion trajectory curve, which can achieve higher precision and smoother bending effect. The saving and downloading of curve formulas can save the optimal parameters for the corresponding steel bar production and customize the name of the saved parameter files; the saving and downloading of curve formulas can save the time of configuring parameters during repeated or batch production.

[0105] The fitting adjustment of the electronic cam parameters in step 2 includes the following steps:

[0106] Step 21: fitting the trajectory curve of the cam according to the set fitting conversion table;

[0107] Step 22: Perform symmetry correction on the fitted cam curve, and set the curve setting of the first half to achieve symmetric setting of the first half and the second half through the curve symmetry function;

[0108] Step 23: Cache and back up the curve data;

[0109] Step 24: Perform a curve translation operation on the curve data that has completed the symmetry correction in step 22, and compensate the curve data by translating the curve left and right to achieve a midpoint symmetric effect;

[0110] Step 25: Perform a curve scaling operation on the curve data that has completed translation, vertically zoom in or out the motion trajectory curve data of the simulated cam 1, obtain the motion trajectory curve data of the simulated cam 2, and realize the adjustment of the overall data;

[0111] Step 26: Re-establish the cam trajectory curve of the simulated cam 1, and establish the cam trajectory curve of the simulated cam 2 according to the offset.

[0112] like Figure 5 As shown, the horizontal axis of the trajectory curve of the cam in step 21 represents the main shaft position, that is, the virtual length of the transmission servo feeding steel bar, and the vertical axis represents the position of the electronic cam. The fitting conversion table includes a 43-point fitting conversion table and a 63-point fitting conversion table, wherein the 43-point fitting conversion table is shown in Table 1, and the 63-point fitting conversion table is shown in Table 2:

[0113] Table 1 43-point cam curve fitting conversion table

[0114]

[0115]

[0116]

[0117] Table 2 63-point cam curve fitting conversion table

[0118]

[0119]

[0120]

[0121]

[0122] The velocities and accelerations in Tables 1 and 2 are both vectors in the longitudinal direction, i.e., the direction perpendicular to the feeding direction of the steel bar.

[0123] like Figure 6 As shown, in step 22, the fitting curve is symmetrically corrected to achieve symmetrical settings of the first half and the second half, greatly improving the user's adjustment efficiency. The symmetrical correction formula of the cam track curve of the electronic cam is shown as follows:

[0124] If the cam track curve of the simulated cam 1 is divided by 43 point data, that is, the length of the steel bar is set to the short size, where:

[0125] TF[(43-n+1)]=TF[n]M=0;n>=1;

[0126] TF[(43-n+1)]=TF[n+2M]M>0,M<=5;n>=2;

[0127] TF[(43-n+1)+2M]=TF[n]M<0,M>=-5; n>=2;

[0128] Wherein n represents the number of curve points, TF[n] represents the vertical coordinate value corresponding to the nth curve point in the trajectory curve of the simulated cam 1; M represents the translation parameter. It should be noted that, in this embodiment, the translation of the curve is performed after the symmetry correction of the curve, and M is 0 at this time. In some other implementation methods, the translation operation of the curve can also be performed first, and then the symmetry correction of the curve can be performed.

[0129] If the cam track curve of the simulated cam is divided by 63 point data, that is, the length of the steel bar is set to the long dimension, where:

[0130] TF[(63-n+1)]=TF[n]M=0;n>=1;

[0131] TF[(63-n+1)]=TF[n+2M]M>0,M<=5;n>=2;

[0132] TF[(63-n+1)+2M]=TF[n]M<0,M>=-5; n>=2;

[0133] Where n represents the number of curve points, TF[n] represents the vertical coordinate value of the position of the nth curve point in the trajectory curve of the simulated cam 1; M represents the translation parameter.

[0134] like Figure 7 , 8 As shown, the curve translation operation in step 24 is as shown in the following formula:

[0135] TF[n]=Copy_TF[nM]nM>0 and n>=2;

[0136] Wherein M represents the translation parameter; TF[n] represents the vertical coordinate value of the nth curve point in the trajectory curve of the simulated cam 1, which in this case is the vertical coordinate value of the nth curve point after the symmetrical correction in step 22; Copy_TF[nM] represents the cache backup array of the nMth point of the cache backup data of the simulated cam 1 in step 23.

[0137] like Fig. 9 , 10 As shown, in step 25, the formula for curve scaling is as follows:

[0138] TW[n]=TF[n]*s;

[0139] Where TF[n] represents the ordinate value of the position of the nth curve point in the trajectory curve of the simulated cam 1; TW[n] represents the ordinate value of the position of the nth curve point in the trajectory curve of the simulated cam 2; s represents the scaling ratio. If the short size is selected, 1<=n<=43; if the long size is selected, 1<=n<=63.

[0140] In step 26, the cam curve is re-established, and the relationship between the actual bending servo and the cam table fitting curve needs to be converted and converted. The line segment in the 43-point short dimension is evenly divided into 39 segments, and the 20th line segment is the median line segment, which includes 4 small line segments; similarly, the line segment in the 63-point long dimension is evenly divided into 59 segments, and the 30th line segment is the median line segment, which includes 4 small line segments; by dividing the median line segment to include small line segments, the motion trajectory of the cam can be more accurate when the steel bar is processed in the middle bending part, and a smooth transition of the bending part can be achieved. Taking the short size as an example, according to Table 1, the virtual stroke length of the spindle for setting the simulated cam 1 is 29250, where the spindle feed amount corresponding to each curve point is expressed as P, P = 29250 / 39, the spindle represents the transmission servo, and the virtual stroke length of the spindle represents the length of the steel bar fed by the transmission servo; the scaling parameter K of the spindle is expressed as K = L / 29250, where L represents the steel bar cutoff length set in step 2, and the scaling parameter K represents the actual length of the steel bar fed by the spindle, that is, the multiple relationship between the actual cutoff length and the simulated virtual stroke length of the spindle. The spindle position is shown in the following formula:

[0141] ZD[n]=P*(n-1); 1<=n<=20;

[0142] ZD[n]=P*19+(P / 4)*(n-20); 21<=n<=23;

[0143] ZD[n]=P*(n-4); 24<=n<=43;

[0144] Where ZD[n] represents the feed length of the spindle when the spindle feeds the steel bar from the nth curve point to the simulated cam 1, and is represented as the horizontal coordinate corresponding to the nth curve point in the trajectory curve of the simulated cam 1;

[0145] The simulated cam position is shown as follows:

[0146] CD[n]=TF[n];1<=n<=43;

[0147] Wherein CD[n] represents the position of the simulated cam 1 corresponding to the nth curve point when the steel bar is fed;

[0148] The linkage speed of the simulated cam 1 is shown as follows:

[0149] V[n]=(CD[n]-CD[n-1]) / P; 2<=n<=20 and 24<=n<=43;

[0150] V[n]=(CD[n]-CD[n-1]) / (P / 4); 21<=n<=23;

[0151] V[1]=V[2]; n=1;

[0152] Wherein V[n] represents the velocity in the longitudinal direction at the nth curve point in the trajectory curve of the simulated cam 1.

[0153] Similarly, according to Table 1, the virtual stroke length of the spindle corresponding to the set analog cam 2 is also 29250, so the displacement P of each point of the spindle is expressed as P=29250 / 39; the scaling parameter K of the spindle is expressed as K=L / 29250, where L represents the cut-off length of the steel bar set in step 2; the actual translation amount fine-tuning is E, and the converted translation amount fine-tuning is e, e=E / K. It should be noted that the translation amount fine-tuning is the compensation amount for the curve translation. The spindle position is shown in the following formula:

[0154] ZDX[n]=P*(n-1); 1<=n<=(1+2M);

[0155] ZDX[n]=P*(n-1)+e;(1+2M) <n<=(20+M);

[0156] ZDX[n]=P*(20+M)+(P / 4)*(n-20); (21+M)<=n<=(23+M);

[0157] ZDX[n]=P*(n-4)+e; (24+M)<=n<=43;

[0158] Where ZDX[n] represents the feed length of the spindle corresponding to the nth curve point of the simulated cam 2, and is represented as the horizontal coordinate of the nth curve point in the steel bar trajectory curve of the simulated cam 2;

[0159] The analog cam second position is shown as follows:

[0160] CDX[n]=TW[n]+g; 1<=n<=43;

[0161] Wherein, CDX[n] represents the position of the simulated cam 2 corresponding to the nth curve point in the trajectory curve of the simulated cam 2; g represents the position offset between the simulated cam 1 and the simulated cam 2, that is, the interval distance between the simulated cam 1 and the simulated cam 2;

[0162] The linkage speed of the simulated cam 2 is shown in the following formula:

[0163] VX[n]=(CD[n]-CD[n-1]) / P; 2<=n<=(20+M) and (24+M)<=n<=43;

[0164] VX[n]=(CD[n]-CD[n-1]) / (P / 4); (21+M)<=n<=(23+M);

[0165] VX[1]=VX[2];n=1;

[0166] Wherein VX[n] represents the velocity in the longitudinal direction when simulating the nth curve point of the second track curve of the cam.

[0167] The production quantity of the steel bars in step 7 is determined according to the number of actions of the middle cutting servo or the steel bar truncation servo, wherein the production quantity of the steel bars is w, and the number of actions of the middle cutting servo or the steel bar truncation servo is v, w=v-1. In the implementation process, the middle cutting servo and the steel bar truncation servo act for the first time to cut off one end of the steel bar a1 and cut and punch the middle of the steel bar a1; the middle cutting servo and the steel bar truncation servo act for the second time to separate the steel bar a1 from the steel bar a2 and cut and punch the middle of the steel bar a2, so after v actions, w steel bars can be obtained.

[0168] During the implementation process, by setting up two simulated electronic cams and synchronously controlling cam mechanism one and cam mechanism two, stress relief operation of steel bar bending is realized, thereby improving the stability and service life of the product. On the other hand, setting up the electronic cam for simulation facilitates machine debugging and can improve the debugging efficiency of the product. By fitting and adjusting the electronic cam parameters, including symmetry correction, curve translation, and curve scaling, better steel bar bending effects can be achieved.

[0169] The above description is only a specific example of the present invention and does not constitute any limitation to the present invention. It is obvious that for professionals in this field, after understanding the content and principle of the present invention, various modifications and changes in form and details may be made without departing from the principle and structure of the present invention, but these modifications and changes based on the idea of ​​the present invention are still within the scope of protection of the claims of the present invention.

Claims

1. A method for bending a wiper steel bar, characterized in that: The steps include: Step 1: The motion controller downloads the processing formula of the steel bar according to the input of the HMI human-machine interface; Step 2: The motion controller adjusts the processing formula according to the input of the HMI human-machine interface, including the adjustment of the steel bar data and the fitting adjustment of the electronic cam parameters; the steel bar data includes the cut-off length and the production quantity, and the electronic cam parameters include the curve offset, curve translation, data scaling and curve symmetry data; and sends the adjusted processing formula data, the electronic cam includes the analog cam 1 and the analog cam 2, which correspond to the simulation states of the cam mechanism 1 and the cam mechanism 2 respectively, by dividing the cam motion trajectory curves of the analog cam 1 and the analog cam 2, the cam mechanism is controlled according to the cam motion trajectory curve; Step 3: The motion controller controls the center cutting servo and the steel bar cutting servo to the specified position; Step 4: The motion controller controls the steel bar unwinding mechanism and the transmission servo to start the action and continuously feed the steel bar; Step 5: The motion controller controls the bending servo and the stress relief servo to perform linkage feeding according to the fitted and adjusted electronic cam parameters; Step 6: After the length of the steel bar fed by the transmission servo reaches the cut-off length, the motion controller controls the middle cutting servo and the steel bar cut-off servo to move; Step 7: The motion controller determines whether the production quantity of steel bars meets the input cutting quantity requirement; if it is less than the input production quantity, it returns to step 4; otherwise, it ends the step.

2. A method for bending a wiper steel bar according to claim 1, characterized in that: The input of the HMI human-machine interface in step 1 includes manual control options, parameter settings, curve settings, and curve recipe saving and downloading; the manual control option is used to realize the jog control of each axis; the parameter setting is used to set the equipment parameters, including the running speed of each servo; the curve setting includes two modes, long size and short size, and the long size and short size are determined according to the cut-off length of the steel bar, and the data points of the long size mode are more than the data points of the short size mode; Saving and downloading the curve formula can save the optimal parameters for the corresponding steel bar production and customize the name of the saved parameter file. The production quantity of the steel bars in step 7 is determined according to the number of actions of the median cutting servo or the steel bar truncation servo, wherein the production quantity of the steel bars is w, and the number of actions of the median cutting servo or the steel bar truncation servo is v, w=v-1, the median cutting servo and the steel bar truncation servo act for the first time to cut off one end of the steel bar a1 and cut and punch the middle of the steel bar a1; the median cutting servo and the steel bar truncation servo act for the second time to separate the steel bar a1 and the steel bar a2 and cut and punch the middle of the steel bar a2, so that w steel bars can be obtained after v actions.

3. A method for bending a wiper steel strip according to claim 1, characterized in that: The fitting adjustment of the electronic cam parameters in step 2 includes the following steps: Step 21: fitting the trajectory curve of the cam according to the set fitting conversion table; Step 22: Perform symmetry correction on the fitted cam curve, and set the curve setting of the first half to achieve symmetric setting of the first half and the second half through the curve symmetry function; Step 23: Cache and back up the curve data; Step 24: performing a curve translation operation on the curve data that has completed symmetry correction in step 22; Step 25: Perform a curve scaling operation on the curve data that has completed translation, vertically zoom in or out the motion trajectory curve data of the simulated cam 1, obtain the motion trajectory curve data of the simulated cam 2, and realize the adjustment of the overall data; Step 26: Re-establish the cam trajectory curve of the simulated cam 1, and establish the cam trajectory curve of the simulated cam 2 according to the offset.

4. A method for bending a wiper steel bar according to claim 3, characterized in that: In step 22, the fitting curve is symmetrically corrected to achieve symmetrical setting of the first half and the second half. The symmetrical correction formula of the cam track curve of the electronic cam is shown as follows: If the cam track curve of the simulated cam is divided by X point data, where: TF[(X-n+1)]=TF[n]M=0;n>=1; TF[(X-n+1)]=TF[n+2M]M>0,M<=5;n>=2; TF[(X-n+1)+2M]=TF[n]M<0,M>=-5; n>=2; Where n represents the number of curve points, TF[n] represents the vertical coordinate value corresponding to the nth curve point of the simulated cam 1; M represents the translation parameter.

5. The method for bending a wiper steel bar according to claim 3, characterized in that: The curve translation operation in step 24 is as shown in the following formula: TF[n]=Copy_TF[nM]nM>0 and n>=2; Wherein M represents the translation parameter; TF[n] is the ordinate value of the nth curve point after the symmetric correction in step 22; Copy_TF[nM] represents the cache backup array of the nMth point of the cache backup data of the simulated cam 1 in step 23.

6. A method for bending a wiper steel bar according to claim 3, characterized in that: In the step 26, the cam curve is re-established, and the relationship between the actual bending servo and the cam table fitting curve needs to be converted and converted. The virtual stroke length of the spindle is set to Y, and the motion trajectory curve of the cam is divided by X point data. The spindle feed corresponding to each curve point is expressed as P, P = Y / (XZ), and Z represents the number of segments contained in the median segment of the motion trajectory curve of the cam; the scaling parameter K of the spindle is expressed as K = L / Y, and L represents the steel bar cutoff length set in step 2; the spindle position is shown in the following formula: ZD[n]=P*(n-1); ZD[n]=P*(n-Z); Where ZD[n] represents the horizontal coordinate corresponding to the nth curve point in the simulated cam track curve; The simulated cam position is shown as follows: CD[n]=TF[n];1<=n<=X; Wherein CD[n] represents the position of the simulated cam 1 corresponding to the n-th curve point in the trajectory curve of the simulated cam 1; TF[n] represents the ordinate value corresponding to the n-th curve point of the simulated cam 1; The linkage speed of the simulated cam 1 is shown as follows: V[n] = (CD[n] - CD[n-1]) / P; And V[n]=(CD[n]-CD[n-1]) / (P / Z); V[1]=V[2]; n=1; Where V[n] represents the velocity in the longitudinal direction at the nth curve point in the trajectory curve of the simulated cam 1; Assume that the actual translation fine adjustment of the simulated cam 2 is E, and the converted translation fine adjustment is e, e = E / K, and the spindle position is as follows: ZDX[n]=P*(n-1); 1<=n<=(1+2M); ZDX[n]=P*(n-1)+e; ZDX[n]=P*(n-Z)+e; Where ZDX[n] represents the horizontal coordinate corresponding to the nth curve point in the trajectory curve of the simulated cam 2; The analog cam second position is shown as follows: CDX[n]=TW[n]+g; 1<=n<=X; Wherein CDX[n] represents the position of the simulated cam 2 at the nth curve point in the trajectory curve of the simulated cam 2; TW[n] represents the ordinate value of the position of the nth curve point in the trajectory curve of the simulated cam 2; g represents the position offset between the simulated cam 1 and the simulated cam 2; The linkage speed of the simulated cam 2 is shown in the following formula: VX[n] = (CD[n] - CD[n-1]) / P; And VX[n]=(CD[n]-CD[n-1]) / (P / Z); VX[1]=VX[2];n=1; Where VX[n] represents the velocity in the longitudinal direction when simulating the nth curve point of the second track curve of the cam.

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