Independent double-drive synchronous precision detection and compensation method for numerical control machine tool

Abstract

The invention relates to the technical field of numerical control machine tool precision debugging, and discloses a numerical control machine tool independent double-drive synchronous precision detection and compensation method, which comprises the following steps: setting a detection point number according to a stroke range of a double-drive shaft, thereby calculating a detection step pitch and setting a plurality of detection point positions; secondly, an NC program is programmed and started, the double-drive shaft is sequentially controlled to move to the set detection point positions in the forward direction and the reverse direction, and then numerical values corresponding to the gradienter on a double-drive shaft cross beam at the detection point positions are read; then, according to the actual machining precision requirement, the obtained gradienter value is subjected to data processing, and therefore the corresponding double-drive shaft synchronization precision errors at all the detection point positions within the double-drive shaft stroke range are obtained; and finally, compensating the other shaft by using the synchronous precision error of the double-drive shaft and taking any one shaft of the double-drive shaft as a compensation reference. According to the method, the machine tool double-drive shaft synchronization precision error detection can be completed by using a conventional monitoring device, and the purchase or lease cost of expensive detection devices is saved.

Description

Technical Field

[0001] The present invention relates to the technical field of precision debugging of numerically controlled machine tools, and more specifically to a method for detecting and compensating the independent dual-drive synchronous precision of numerically controlled machine tools. Background Art

[0002] If there is a synchronization accuracy deviation during the synchronous movement of the dual-drive axes, the current and load of the drive motor will be too large, affecting the service life of the motor and drive module components. It will also cause abnormal wear on the mechanical drive components. Especially for CNC machine tools with vertical axes configured as dual-drive axes, the impact of synchronization accuracy deviation on mechanical and electrical is particularly aggravated.

[0003] For example, the invention patents disclosed as CN114473631A and CN113188479A respectively disclose a method for synchronous adjustment of the gantry of a dual-drive system and a method for detecting the parallelism of a large-span guide rail. The above two patents respectively set up laser interferometers on the dual-drive shafts to obtain the position error of the dual-drive shafts, and then compensate the obtained error to the pitch error system. The patented method requires two sets of laser interferometers for detection. The equipment is expensive, and the two sets of laser interferometers need to be used in conjunction. The technical difficulty is high, the operation is cumbersome, and the detection takes a long time.

[0004] For another example, the invention patent with publication number CN103551627A discloses a deep hole processing method for a gantry pentahedron CNC machine tool, which detects the levelness of the workbench during its movement by placing two electronic levels on the workbench along the X-axis and Y-axis. However, the patent method detects the levelness of the workbench and adjusts it to meet the requirements through anchor screws, which is a conventional detection and adjustment method in the industry. Summary of the invention

[0005] The present invention proposes a method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool. By using a high-precision level and a mounting bracket, the synchronization accuracy error data of multiple detection points of the dual-drive axis within the travel range is obtained, and then the synchronization accuracy error data is used to compensate one axis with one axis as the compensation reference. The present invention solves the problem that the vertical axis of a CNC machine tool is configured as a dual-drive axis and there is a synchronization accuracy error during the movement process.

[0006] In order to achieve the above-mentioned object of the invention, the technical solution of the present invention is as follows:

[0007] The present invention discloses a method for detecting and compensating the independent dual-drive synchronization accuracy of a numerically controlled machine tool, the method comprising the following steps:

[0008] Step S1. First, install an L-shaped or other shaped bracket on the dual-drive shaft beam, and then install and place the spirit level on the bracket. During the detection process, the spirit level moves together with the dual-drive shaft beam; then, the number of detection points within the travel range is set according to the travel range of the dual-drive shaft, thereby calculating the detection step distance and setting multiple detection points, and each detection point has corresponding coordinates.

[0009] In the present invention, the travel range of the dual drive shaft is n=|n max |+|n min |, where n max is the maximum limit of the coordinates of the dual-drive axis, n min The minimum limit of the coordinates of the dual-drive axis is usually set to ensure the normal operation of the machine tool. max Generally, 10mm is subtracted from the maximum limit of the dual-drive axis coordinates. min Generally, 10mm is added to the minimum limit of the dual-drive axis coordinates.

[0010] Furthermore, the calculation expression of the detection step U is as follows:

[0011]

[0012] Wherein, m is the number of set detection points.

[0013] Step S2. Compile and start the NC program, control the dual-drive axes to move to the set detection points in sequence, and then read the level value corresponding to the detection point.

[0014] In the present invention, during the precision detection process, the dual-drive shaft will usually first move in the forward direction to the set detection points in sequence, at which time the values ​​of the level corresponding to each detection point during the forward movement can be obtained; then the dual-drive shaft moves in the reverse direction, and when it moves to the corresponding detection point, the value of the level is read, and finally two sets of level values, namely the values ​​of the level corresponding to each detection point during the forward movement and the values ​​of the level corresponding to each detection point during the reverse movement, can be obtained.

[0015] In the present invention, when the machine tool NC program is started, the data acquisition function or data monitoring function (TRACE function) of the CNC machine tool is usually started synchronously to collect the current value of the dual-drive axis during the movement.

[0016] In the present invention, the NC program compiled in step S2 takes the dual-drive axis Y axis as an example, and the program is as follows:

[0017] G500; activate the machine coordinate system

[0018] G01 F5000 Y=n min ; 5000mm / minMove the Y axis to the set detection point T1 at a speed of

[0019] M0; the program pauses, adjusts the position of the level so that the pointer points to zero, and records it as value V1

[0020] CYCLEA G91 Y=U G4 F5; Continue to execute the program and move the Y axis in incremental feed mode. The incremental feed amount is U. After reaching the target position T2, pause for 5S and record the level value V2

[0021] REPEAT CYCLEA P=m-2; repeat the above CYCLEA program segment, the number of cycles is P, and the final movement Y axis position is n max , record the arrival at the target position (T3, T4----T m ) when the level value (V3, V4...V m )

[0022] G91 Y=5; Y axis continues to move forward 5mm

[0023] G91 Y=-5G4 F5; Y axis moves back 5mm and pauses for 5S, recording the level value V m+1

[0024] CYCLEB G91 Y=-U ​​G4 F5; Set the Y axis to move in incremental feed mode, the incremental feed amount is -U, pause for 5S after reaching the target position, and record the level value V m+2

[0025] REPEAT CYCLEB P=m-2; loop the above CYCLEB program segment, the number of cycles is P, and the final moving Y axis position is n mmn , record the level value (V m+3 、V m+4 ……V m+m )

[0026] M30; program ends

[0027] Step S3. According to the actual processing accuracy requirements, the two sets of level value values ​​obtained in step S2 are processed, and the dual-drive shaft synchronization accuracy error corresponding to each detection point within the dual-drive shaft stroke is calculated.

[0028] Step S4. Use the calculated dual-drive shaft synchronization accuracy error and take any one of the dual-drive shafts as the compensation reference to compensate the other shaft.

[0029] When using machine tools to process products, if the product processing accuracy requirements are low, or the number of detection points initially set is large, the average values ​​of the two sets of level values ​​can be proportionally amplified and used as the synchronization accuracy error to compensate the accuracy of the dual-drive axis. The specific process is as follows:

[0030] When the dual-drive shaft moves forward and backward to the same detection point, the two level values ​​obtained are averaged and the calculation expression is as follows:

[0031] H m =(V m +V m+1 ) / 2;

[0032] Among them, H m The dual drive axis moves forward and reverse to the same detection point T m The average value of the corresponding level value; V m The dual drive axis moves forward to the detection point T m Level value at 1:00: m+1 The dual drive shaft moves in the opposite direction to the detection point T m Level value at 12:00;

[0033] Then the average value H of the level value of all the detection points is obtained. m According to the size of the level and the size of the dual-drive axis beam, the synchronous accuracy error corresponding to each detection point is calculated. The calculation expression is as follows:

[0034] Q / W=H m / S;

[0035] S=WH m / Q;

[0036] Among them, Q is the length of the level; S is the synchronization accuracy error corresponding to the detection point; W is the length of the dual-drive axis beam;

[0037] Furthermore, the synchronization accuracy error obtained by the above calculation is used to perform accuracy compensation on the dual-drive shaft. The specific process is as follows:

[0038] 1) If the active axis is used as the compensation reference to compensate the driven axis, the compensation process is as follows:

[0039] If the synchronization accuracy error S>0, it means that the active axis is high and the driven axis is low when the dual-drive axis moves, then the compensation value of the driven axis is +S;

[0040] If the synchronization accuracy error S<0, it means that the active axis is low and the driven axis is high when the dual-drive axis moves, then the compensation value of the driven axis is -|S|, where |S| means taking the absolute value of the synchronization error value S;

[0041] 2) If the driven axis is used as the compensation reference to compensate the driving axis, the compensation process is as follows:

[0042] If the synchronization accuracy error S>0, it means that the active axis is high and the driven axis is low when the dual-drive axis moves, then the compensation value of the active axis is -S;

[0043] If the synchronization accuracy error S<0, it means that the active axis is low and the driven axis is high when the dual-drive axis moves, then the compensation value of the active axis is +|S|, and |S| means taking the absolute value of the synchronization error value S.

[0044] Furthermore, the compensation value is input into the compensation system. The compensation list template program is as follows:

[0045] ﹩AN_CEC[D,1]=S1;

[0046] ﹩AN_CEC[D,2]=S2;

[0047] ……;

[0048] ﹩AN_CEC[D, m]=S m ;

[0049] ﹩AN_CEC_INPUT[D]=E;

[0050] ﹩AN_CEC_OUTPUT[D]=F;

[0051] ﹩AN_CEC_STEP[D]=(|n max |+|n min |) / m

[0052] ﹩AN_CEC_MIN[D]=n min ;

[0053] ﹩AN_CEC_MAX[D]=n max ;

[0054] Where, E represents the reference coordinate axis (input axis), F represents the coordinate axis to be compensated (output axis), D represents the axis number corresponding to the axis to be compensated, and m represents the number of detection points divided by the motion range on the reference coordinate axis, (S1, S2...S m ) indicates the m compensation values ​​corresponding to the detection point. It is necessary to determine which axis is the compensation reference axis according to the actual compensation mode of the machine tool and then modify the compensation value; ﹩AN_CEC_ is a special symbol for the compensation module of the CNC system, n min 、n max Respectively represent the minimum and maximum values ​​of the running stroke.

[0055] When the data obtained after proportional amplification using the average value is used as the synchronization accuracy error to perform accuracy compensation on the dual-drive shaft, the compensation efficiency can be improved and the effect of rapid compensation and adjustment of the dual-drive shaft can be achieved.

[0056] If the product processed by CNC machine tools has high processing accuracy requirements, or the number of detection points initially set is small (it is considered that the compensation points are insufficient), the accuracy compensation effect of the machine tool is not ideal and the compensation effect is poor after the average value is proportionally amplified. Therefore, the present invention also provides another method for calculating the synchronization accuracy error, which is used to improve the compensation accuracy of the machine tool. The specific process is as follows:

[0057] After the above-mentioned average value of the level meter is amplified by equal proportion, the corresponding synchronization accuracy error of each detection point is obtained, and the coordinates of each detection point and its corresponding synchronization accuracy error are subjected to binomial fitting processing, and finally the fitting relationship between the synchronization accuracy error and the detection point coordinates is obtained, and the following fitting relationship is obtained:

[0058] S=W0+W1T+W2T 2 ;

[0059] Wherein, T is the point to be compensated; S is the synchronization accuracy error; W0 is the polynomial constant term, W1 is the polynomial first-order term, and W2 is the polynomial second-order term;

[0060] In the above fitting relationship, the fitting coefficient is calculated using the coordinates of the detection point and its corresponding synchronization accuracy error. The calculation formula is as follows:

[0061]

[0062] Among them, T i , S i are the coordinates of the i-th detection point and its corresponding synchronization accuracy error;

[0063] Based on the above fitting relationship, more points to be compensated are set according to the actual processing accuracy requirements, or the coordinate values ​​of more compensation points are substituted into the above fitting relationship according to the compensation points in the compensation list when the machine tool leaves the factory, and the corresponding synchronous accuracy error values ​​are calculated. Then, the synchronous accuracy error values ​​are used for accuracy compensation. The specific accuracy compensation method can refer to the above-mentioned process of compensation using the average value, which will not be described in detail here.

[0064] Furthermore, in order to verify the effect of the above-mentioned precision compensation and ensure the machining accuracy of the machine tool, the present invention also includes a precision compensation verification step, and the specific process is as follows:

[0065] First, the current value of the dual-drive axis during the motion process collected by the NC program in step S2 is filtered, that is, the current value at the moment of starting and stopping the drive axis is filtered out to obtain the effective maximum value I of the dual-drive axis current. max1 ;

[0066] Then, the NC program in step S2 is executed again and the machine tool data acquisition function or data monitoring function is turned on at the same time to obtain a new effective maximum current value I max2 , and execute step S3 again to obtain a new synchronization accuracy error, and then select the value with the largest absolute value in the new synchronization accuracy error as the maximum error value S max ; Finally, use the new maximum synchronization accuracy error S max And the effective maximum current I max2 , verify the accuracy compensation effect.

[0067] Furthermore, the verification process of the accuracy compensation effect is as follows:

[0068] Step 1. If S max The value of is less than or equal to the accuracy allowed value, and I max2 The value is less than or equal to I max1 When the precision compensation effect is good, it meets the processing requirements of machine tools;

[0069] Step 2. If S max The value is less than or equal to the accuracy allowed value, I max2 The value is greater than I max1 When the precision compensation effect is good, there is stress on the beam connecting the dual-drive shaft, which will have an unfriendly effect on the mechanical drive components. The mechanical components need to be adjusted for stress release.

[0070] Step 3. If S max The value is greater than the accuracy allowed, I max2 The value is greater than I max1 When the precision compensation effect is not good, the compensation parameters do not match the mechanical state, and the mechanical drive components need to be adjusted accordingly;

[0071] Step 4. If S max The value is greater than the accuracy allowed, I max2 The value is less than I max1 When the accuracy compensation effect is not ideal, the above detection and compensation steps need to be performed again until S max and I max2 The value of meets the requirements.

[0072] In the present invention, the allowable accuracy value is set by the technicians themselves, and can be set according to the structure of the machine tool, or can be obtained by querying relevant accuracy calibration.

[0073] Beneficial effects of the present invention:

[0074] 1. The present invention can complete the detection of the synchronization accuracy error of the dual-drive axes of a machine tool using conventional monitoring instruments, thus saving a large amount of expensive purchase or rental costs of detection equipment and having considerable economic benefits.

[0075] 2. The method of the present invention has simple and convenient operation steps, and can be completed by ordinary technicians through simple training, which has the economic significance of large-scale technology promotion.

[0076] 3. The detection and compensation time of the method of the present invention is short, which can avoid a lot of equipment downtime. BRIEF DESCRIPTION OF THE DRAWINGS

[0077] The foregoing and following detailed description of the present invention will become more apparent when read in conjunction with the following drawings, in which:

[0078] Figure 1 This is a schematic diagram of the use of the level meter of the present invention in conjunction with an L-shaped bracket;

[0079] Figure 2 This is a schematic diagram of synchronization accuracy detection of the present invention;

[0080] Figure 3 It is a schematic diagram of the dual-drive axis posture when the synchronization error accuracy of the present invention is greater than zero;

[0081] Figure 4 This is a schematic diagram of the dual-drive axis posture when the synchronization error accuracy of the present invention is less than zero.

[0082] In the figure:

[0083] 1. Level; 2. L-shaped bracket; 3. Mounting hole; 4. Driven shaft; 5. Dual drive shaft crossbeam; 6. Driving shaft. DETAILED DESCRIPTION

[0084] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions for achieving the purpose of the present invention will be further described below through specific embodiments. It should be noted that the technical solutions claimed for protection in the present invention include but are not limited to the following embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those skilled in the art without creative work shall fall within the scope of protection of the present invention.

[0085] If there is a synchronization accuracy deviation during the synchronous movement of the dual-drive axes, the current and load of the drive motor will be too large, affecting the service life of the motor and drive module components. It will also cause abnormal wear on the mechanical drive components. Especially for CNC machine tools with vertical axes configured as dual-drive axes, the impact of synchronization accuracy deviation on mechanical and electrical is particularly aggravated.

[0086] At present, the detection of the synchronization accuracy of the dual-drive shaft is usually carried out by setting up laser interferometers on the dual-drive shafts to obtain the position error of the dual-drive shafts, and then compensating the obtained error to the pitch error system. In the entire compensation detection process, two sets of laser interferometers are used. The laser interferometers are expensive, resulting in high detection costs. In addition, the two sets of laser interferometers need to be used in conjunction during the detection process, which is technically difficult, cumbersome to operate, and takes longer to detect.

[0087] Based on this, an embodiment of the present invention proposes a method for independent dual-drive synchronization accuracy detection and compensation of CNC machine tools. This method uses a conventional level to complete the machine tool dual-drive axis synchronization accuracy error detection and compensation, saving a large amount of expensive detection equipment purchase or rental costs, and has considerable economic benefits.

[0088] The present invention will be explained and illustrated in more detail below in conjunction with specific implementation methods.

[0089] Example 1

[0090] The present embodiment discloses a method for detecting and compensating the precision of independent dual-drive synchronization of a CNC machine tool. The method uses a device including a high-precision level and an L-shaped bracket. The screw holes of the L-shaped bracket are consistent with the screw holes on the dual-drive axis crossbeam. Before starting the machine tool for precision detection, the L-shaped bracket is installed on the dual-drive axis crossbeam, and then the level is placed on the L-shaped bracket. The placement direction of the level is parallel to the dual-drive axis crossbeam, such as Figure 1 and Figure 2 As shown, after the level is installed in place, the compiled NC program is started to start accuracy detection and compensation. The specific solutions adopted are as follows:

[0091] Take the Y axis of a CNC machine tool as an example. The negative soft limit of the machine tool is set to -1285mm and the positive soft limit is set to 1215mm. The number of detection points within the travel range is set to m = 9, then n max =1215-10=1205mm, n min =-1285+10=-1275mm, moving range n=|n max |+|n min |=2480mm; further calculate the detection step distance The corresponding NC program is listed as follows. Start the NC program and perform the corresponding detection steps:

[0092] G500; activate the machine tool coordinate system;

[0093] G01 F5000 Y=n min =-1275; 5000mm / minMove the Y axis to the set detection point T1 at a speed of T1 = -1275;

[0094] M0; the program pauses, adjusts the position of the level so that the pointer points to zero, and records the value V1 of the level;

[0095] CYCLEAG91 Y=U=310G4 F5; Continue to execute the program to move the Y axis in incremental feed mode, the incremental feed amount is 310, and pause for 5S after reaching the next detection point T2=-965, and record the level value V2;

[0096] REPEAT CYCLEAP=m-2=7; repeat the above CYCLEA program segment, the number of cycles is 7, and the final movement Y axis position is n max =1205, record the level value (V3, V4...V9) when reaching the target position (T3, T4...T9)

[0097] G91 Y=5; Y axis continues to move forward 5mm

[0098] G91 Y=-5G4 F5; Y axis moves back 5mm and pauses for 5S, recording the level value V 10

[0099] CYCLEB G91 Y=-U ​​G4 F5; Set the Y axis to move in incremental feed mode, the incremental feed amount is -U, pause for 5S after reaching the target position, and record the level value V 11

[0100] REPEAT CYCLEB P=m-2=7; loop the above CYCLEB program segment, the number of cycles is 7, and the final moving Y axis position is n min , record the level value (V 12 、V 13┈ V 18 )

[0101] M30; program ends.

[0102] Furthermore, the corresponding relationship between the coordinates of the detection points and the level readings is shown in Table 1 below:

[0103] Table 1 Relationship between detection point coordinates and level readings

[0104]

[0105] The value V in the above table is processed. Specifically, the value V when the dual-drive shaft moves forward and backward to the same coordinate position is averaged to obtain a new value H1=(V1+V 18 ) / 2, H2=(V2+V 17) / 2......H9=(V9+V 10 ) / 2,H m The corresponding relationship with the detection point coordinates is shown in Table 2 below:

[0106] Table 2 Relationship between the average value of the level meter and the coordinates of the detection points

[0107] T(1～9) -1275 -965 -655 -345 -35 275 585 895 1205 H(1～9) 0 0.001 0.003 0.005 0.08 0.011 0.015 0.019 0.022

[0108] Further, the new level value H m According to the same proportion of the size of the level meter and the size of the dual-drive shaft beam, the real synchronization accuracy error S of the dual-drive shaft is calculated. The specific calculation process is as follows:

[0109] Set the length of the level Q = 210mm, the length of the double-drive shaft beam W = 2300mm, then:

[0110] Q / W = H / S;

[0111] S = WH / Q;

[0112] The corresponding relationship between the actual synchronization accuracy error S of the dual-drive axis and the detection point coordinates is calculated as shown in Table 3:

[0113] Table 3 Relationship between the synchronization accuracy error of the dual-drive axis and the coordinates of the detection points

[0114] T(1～9) -1275 -965 -655 -345 -35 275 585 895 1205 S(1～9) 0 0.011 0.033 0.055 0.088 0.121 0.165 0.209 0.242

[0115] Furthermore, assuming that the left axis when facing the dual-drive axis is the driven axis and the right axis is the active axis, the active axis is used as the compensation reference to compensate the driven axis, and the axis number of the driven axis is 7; at this time, the synchronization accuracy error S>0, which means that the active axis is high and the driven axis is low when the dual-drive axis moves, then the compensation value of the driven axis is +S, such as Figure 3 shown.

[0116] Further, the compensation value is input into the compensation system, and the compensation list template program is as follows:

[0117] ﹩AN_CEC[7,1]=0;

[0118] ﹩AN_CEC[7,2]=0.011;

[0119] ……;

[0120] ﹩AN_CEC[7,9]=0.242;

[0121] ﹩AN_CEC_INPUT[7]=Y;

[0122] ﹩AN_CEC_OUTPUT[7]=Y;

[0123] ﹩AN_CEC_STEP[7]=310;

[0124] ﹩AN_CEC_MIN[7]=-1275;

[0125] ﹩AN_CEC_MAX[7]=1205.

[0126] Example 2

[0127] This embodiment discloses a method for detecting and compensating the synchronization accuracy of independent dual-drive axes of a CNC machine tool. Based on the above embodiment 1, this embodiment adopts a different method to calculate the synchronization accuracy error of the dual-drive axes. The details are as follows:

[0128] The coordinates (T1, T2...T9) in the above embodiment 1 and the corresponding synchronization accuracy errors (S1, S2...S9) are fitted with a polynomial, and the polynomial fitting expression is as follows:

[0129] S=W0+W1T+W2T 2 ;

[0130] In the above expression, the fitting coefficient is calculated using the coordinates of the detection point and its corresponding synchronization accuracy error. The calculation formula is as follows:

[0131]

[0132] m is the number of detection points, T i , S i are the coordinates of the detected i-th detection point and its corresponding synchronization accuracy error, as shown in Example 1. Substituting the coordinates (T1, T2...T9) and the corresponding real synchronization accuracy errors (S1, S2...S9) in Example 1 into the calculation formula, we can obtain W0=-1158, W1=1.438×10 -4 , W2=-2.038×10 -4 According to the actual processing requirements, add points to be supplemented, or according to the compensation points stored in the machine tool compensation list, bring the coordinates of more points to be compensated into the above fitting relationship, calculate the synchronization accuracy error value under the coordinates of the points to be compensated, and then call the same dual-drive axis compensation process for compensation.

[0133] Example 3

[0134] The present embodiment discloses a method for detecting and compensating the independent dual-drive synchronization accuracy of a numerically controlled machine tool. On the basis of Embodiment 1 or Embodiment 2, the data acquisition function or data monitoring function of the machine tool is started while the NC program is started, the current value of the dual-drive axis is collected, and the obtained current value is filtered, that is, the current value at the moment of starting and stopping the drive axis is filtered out, and the effective maximum value I of the dual-drive axis current is obtained.max1 =10.57A; after the compensation is completed, the NC program in the above embodiment is executed again and the data acquisition function or data monitoring function is turned on to obtain a new effective maximum current value I max2 =4.37A, and executing the accuracy detection steps in the above embodiment to obtain a new level meter numerical table as shown in Table 4 below.

[0135] Table 4 Relationship between new detection point coordinates and level readings

[0136]

[0137] The positive and negative movement values ​​V corresponding to the same detection point in the above table are averaged to obtain a new level value average, and then the largest absolute value is selected from the above level value averages for the same proportion amplification processing. The compensated S max =WH / Q=0.016mm, finally according to S max and I max2 The compensation effect can be judged by the numerical value of .

[0138] In this embodiment, S max The value is less than the accuracy allowable system 0.05mm, and I max2 The value is less than I max1 , it can be considered that the precision compensation effect is good and meets the machining requirements of machine tools.

[0139] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification or equivalent change made to the above embodiment based on the technical essence of the present invention shall fall within the protection scope of the present invention.

Claims

1. A method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool, characterized in that: The following steps are involved: Step S1. Install the level on the dual-drive shaft beam, set the number of detection points within the travel range according to the travel range of the dual-drive shaft, calculate the detection step distance and set multiple detection points; Step S2. compile and start the NC program, control the dual-drive axis to move to the set detection point in turn, and then read the level value corresponding to the detection point; Step S3. According to the actual machining accuracy requirements, the obtained level value is processed, and the dual-drive shaft synchronization accuracy error corresponding to each detection point within the dual-drive shaft stroke is calculated; Step S4. Use the synchronization accuracy error of the dual-drive axes and take any one of the dual-drive axes as the compensation reference to compensate the other axis.

2. A method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool according to claim 1, characterized in that: In step S2, the travel range of the dual drive axis is n = |nmax| + |nmin|, and the detection step is Among them, n is the travel range of the dual-drive axis; nmax is the maximum limit of the dual-drive axis coordinates; nmin is the minimum limit of the dual-drive axis coordinates; m is the number of detection points; U is the detection step.

3. The method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool according to claim 1, characterized in that: In step S3, according to the actual machining accuracy requirements, the obtained level value is processed, and the dual-drive shaft synchronization accuracy error corresponding to each detection point within the dual-drive shaft stroke is calculated, including: When the dual-drive shaft moves forward and backward to the same detection point, the two level values ​​obtained are averaged and the calculation expression is as follows: H m =(Vm+Vm +1 ) / 2; Among them, H m The dual drive axis moves forward and reverse to the same detection point T m The average value of the corresponding level value; Vm is the positive movement of the dual drive shaft to the detection point T m Level value at 1000 sec; Vm +1 The dual drive shaft moves in the opposite direction to the detection point T m Level value at 12:00; The average values ​​of the level gauges at all the detection points are enlarged in proportion to the size of the level gauge and the size of the dual-drive axis beam, and the synchronization accuracy error corresponding to each detection point is calculated. The calculation expression is as follows: Q / W=H m / S; S=W H m / Q; Among them, Q is the length of the level; S is the synchronization accuracy error corresponding to the detection point; W is the length of the dual-drive axis beam.

4. The method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool according to claim 1, characterized in that: In step S3, according to the actual machining accuracy requirements, the obtained level value is processed, and the dual-drive shaft synchronization accuracy error corresponding to each detection point within the dual-drive shaft stroke is calculated, including: When the dual-drive shaft moves forward and backward to the same detection point, the two level values ​​obtained are averaged and the calculation expression is as follows: H m =(Vm+Vm +1 ) / 2; Among them, H m The dual drive axis moves forward and reverse to the same detection point T m The average value of the corresponding level value; Vm is the positive movement of the dual drive shaft to the detection point T m Level value at 1000 sec; Vm +1 The dual drive shaft moves in the opposite direction to the detection point T m Level value at 12:00; The average values ​​of the level gauges at all the detection points are enlarged in proportion to the size of the level gauge and the size of the dual-drive axis beam, and the synchronization accuracy error corresponding to each detection point is calculated. The calculation expression is as follows: Q / W=H m / S; S=W H m / Q; Among them, Q is the length of the level; S is the synchronization accuracy error corresponding to the detection point; W is the length of the dual-drive axis beam; Furthermore, the obtained synchronization accuracy error at the detection point and the position coordinates at the detection point are fitted with a polynomial to obtain the following fitted synchronization accuracy error calculation expression. Finally, the coordinates of the point to be compensated are substituted into the fitted synchronization accuracy error calculation expression to obtain the synchronization accuracy error corresponding to the point: <h2 style=";text-align:left;direction:ltr">S=W0+W1T+W2T<h2 style=";text-align:left;direction:ltr"> 2 <h2 style=";text-align:left;direction:ltr"> ; Wherein, T is the point to be compensated; S is the synchronization accuracy error.

5. The method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool according to claim 1, characterized in that: In step S4, any one of the dual-drive axes is used as a compensation reference to compensate the other axis, including: 1) Take the driving shaft as the compensation reference to compensate the driven shaft: If the synchronization accuracy error S>0, it means that the active axis is high and the driven axis is low when the dual-drive axis moves, then the compensation value of the driven axis is +S; If the synchronization accuracy error S<0, it means that the active axis is low and the driven axis is high when the dual-drive axis moves, then the compensation value of the driven axis is -|S|, where |S| represents the absolute value of the synchronization accuracy error; 2) Take the driven shaft as the compensation reference to compensate the driving shaft: If the synchronization accuracy error S>0, it means that the active axis is high and the driven axis is low when the dual-drive axis moves, then the compensation value of the active axis is -S; If the synchronization accuracy error S<0, it means that the active axis is low and the driven axis is high when the dual-drive axis moves, then the compensation value of the active axis is +|S|, and |S| represents the absolute value of the synchronization error value.

6. The method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool according to claim 1, characterized in that: The step S2 also includes: starting the data acquisition function or data monitoring function of the CNC machine tool while starting the machine tool NC program, collecting the current value of the dual-drive axis, and filtering the obtained current value to the effective maximum value Imax1 of the dual-drive axis current.

7. A method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool according to claim 6, characterized in that: The method further includes: step S5. executing the NC program in step S2 again and simultaneously starting the machine tool data acquisition function or the data monitoring function to obtain a new effective maximum current value Imax2, and executing step S3 again to obtain a new synchronization accuracy error; selecting the error with the largest absolute value as the error maximum value S in the new synchronization accuracy error. max , use the new maximum synchronization accuracy error S max And the effective maximum current Imax2, verify the accuracy compensation effect.

8. A method for detecting and compensating the independent dual-drive synchronization accuracy of a CNC machine tool according to claim 7, characterized in that: The verification process of the accuracy compensation effect is as follows: Step 1. If S max When the value of is less than or equal to the accuracy allowable value, and the value of Imax2 is less than or equal to Imax1, the accuracy compensation effect is good and meets the machine tool processing requirements; Step 2. If S max When the value of is less than or equal to the accuracy allowable value and the value of Imax2 is greater than Imax1, the accuracy compensation effect is good, but stress exists in the beam connecting the dual-drive shaft; Step 3. If S max When the value of is greater than the accuracy allowable value and the value of Imax2 is greater than Imax1, the accuracy compensation effect is not good; Step 4. If S max When the value of is greater than the accuracy allowable value and the value of Imax2 is less than Imax1, the accuracy compensation effect has not reached the ideal state, and the above detection and compensation steps need to be performed again.

Images