阅读说明：本技术 一种在线厚度检测双伺服系统及方法 (Online thickness detection double-servo system and method ) 是由 郑建 胡美琴 蔡强 陈杰 于 2021-04-26 设计创作，主要内容包括：本发明公开了一种在线厚度检测双伺服系统及方法,包括：控制模块、导向机构和一对相互配合的探头,所述的导向机构包括平行设置的主移动架和从移动架,一对探头分别固定在主移动架和从移动架上；主移动架和从移动架分别由带有驱动器的伺服电机驱动；控制模块输出脉冲至驱动器,驱动器控制伺服电机使主移动架和从移动架同步行走；同时伺服电机反馈编码信号至控制模块,用于实时监测主移动架和从移动架的位置；所述导向机构上还分别固定有用于一对探头复位的零点信号传感器。本发明减少了双探头检测扫描系统中机械同步传动的部件,提升了该类检测扫描设备的安装灵活度；采用双伺服电机控制同步精度,提升了在线厚度检测系统的检测精度。(The invention discloses an online thickness detection double-servo system and method, which comprises the following steps: the probe comprises a control module, a guide mechanism and a pair of mutually matched probes, wherein the guide mechanism comprises a main moving frame and a secondary moving frame which are arranged in parallel, and the pair of probes are respectively fixed on the main moving frame and the secondary moving frame; the main moving frame and the auxiliary moving frame are respectively driven by a servo motor with a driver; the control module outputs pulses to the driver, and the driver controls the servo motor to enable the main moving frame and the auxiliary moving frame to synchronously move; meanwhile, the servo motor feeds back a coding signal to the control module for monitoring the positions of the main moving frame and the auxiliary moving frame in real time; and zero signal sensors for resetting the pair of probes are respectively fixed on the guide mechanisms. The invention reduces the mechanical synchronous transmission parts in the double-probe detection scanning system and improves the installation flexibility of the detection scanning equipment; the synchronous precision is controlled by adopting the double servo motors, so that the detection precision of the online thickness detection system is improved.)

1. An online thickness detection dual servo system comprising: the device comprises a control module, a guide mechanism and a pair of mutually matched probes, and is characterized in that the guide mechanism comprises a main moving frame and a secondary moving frame which are arranged in parallel, and the pair of probes are respectively fixed on the main moving frame and the secondary moving frame; the main moving frame and the auxiliary moving frame are respectively driven by a servo motor with a driver; the control module outputs pulses to the driver, and the driver controls the servo motor to enable the main moving frame and the auxiliary moving frame to synchronously move; meanwhile, the servo motor feeds back a coding signal to the control module for monitoring the positions of the main moving frame and the auxiliary moving frame in real time; and zero signal sensors for resetting the pair of probes are respectively fixed on the guide mechanisms.

2. The on-line thickness measuring dual servo system as claimed in claim 1, wherein the guiding mechanism is a pair of parallel linear guide rail mechanisms; the main moving frame is arranged on the main guide rail in a sliding mode, the auxiliary moving frame is arranged on the auxiliary guide rail in a sliding mode, and the main guide rail and the auxiliary guide rail are respectively fixed with a zero signal sensor.

3. The on-line thickness detection dual servo system as claimed in claim 2, wherein the master rail and the slave rail are fixed with a reverse limit photoelectric sensor and a positive limit photoelectric sensor.

4. The on-line thickness measuring dual servo system as claimed in claim 3, wherein the distance between the zero signal sensor of the primary guide rail and the anti-limit photoelectric sensor is smaller than the distance between the zero signal sensor of the secondary guide rail and the anti-limit photoelectric sensor.

5. The method for the on-line thickness detection dual-servo system according to any one of claims 1 to 4, comprising the following steps:

(1) the control module drives the main servo motor and the slave servo motor to operate through the main driver and the slave driver, so that the main moving frame and the slave moving frame walk in opposite directions to reach zero positions;

(2) keeping the slave driver stopped, and enabling the main driver to operate to drive the main moving frame to move forwards by the main servo motor so as to enable the positions of the main moving frame and the slave moving frame to be staggered;

(3) The main driver operates to enable the main servo motor to drive the main moving frame to reversely walk to a zero position, the control module collects signals output by the probe in real time and collects coding position signals fed back by the main servo motor;

(4) the control module calculates the deviation distance of the zero positions corresponding to the main moving frame and the slave moving frame, and the main servo motor moves the position of the main moving frame by driving the main driver to compensate the deviation distance;

(5) the measured object passes through between a pair of probes, and control module passes through main driver and follows the driver and drives main servo motor and follow servo motor operation simultaneously, makes main removal frame and follow and removes the frame and carry out forward or reverse walking in step, and control module collects the signal of probe output in real time and measures the thickness of measured object.

6. The method for the dual servo system for on-line thickness measurement according to claim 5, wherein in step (1), the control module outputs pulse signals to control the master driver and the slave driver respectively, and stops outputting corresponding pulse signals to stop the master servo motor and the slave servo motor after the zero signal sensor detects that the master moving frame and the slave moving frame respectively reach zero positions.

7. The method for the dual servo system of online thickness measurement as claimed in claim 5, wherein in step (3), the control module converts the current signal fed back from the probe into a 16-bit digital value through its AD module and stores the digital value in a temporary buffer; and meanwhile, orthogonal AB phase coded pulse signals fed back by the main servo motor are collected, a corresponding system position value is updated when one pulse signal changes, and a plurality of current signal digital values temporarily buffered and stored between two pulses are processed by adopting median filtering.

8. The method according to claim 7, wherein in step (4), the control module stores the digital value of the current signal processed in step (3) into a Y-axis memory array, and stores the real-time system position value into an X-axis memory array; and the Y-axis memory array and the X-axis memory array form a two-dimensional curve until the main moving frame returns to the zero position, and the control module calculates the position corresponding to the maximum value of the output signal of the probe to obtain the deviation distance.

9. The method of claim 8, wherein the X-axis is used for the dual servo system for on-line thickness measurementkThe corresponding Y-axis array data is taken out from the continuous array, then kVariation of a continuous arrayComprises the following steps:

wherein the content of the first and second substances,is the X axisiThe Y-axis array data corresponding to the array,is the X axiskThe average value of Y-axis array data of the continuous arrays;

sequentially accumulating the X-axis array data to obtain the variation of the current continuous array; and finally, respectively obtaining two X-axis array data with the largest variation in the ascending section and the descending section of the X-axis array data, wherein the deviation distance of the pair of probes is the data intermediate value of the two X-axis array data with the largest variation.

10. The method for the dual servo system of on-line thickness detection as claimed in claim 5, wherein in step (5), the control module monitors the feedback coded pulse signals of the master servo motor and the slave servo motor, and when the difference between the two pulse values exceeds a set difference value, the scanning system stops running and gives an alarm.

Technical Field

The invention relates to the technical field of industrial detection, in particular to an online thickness detection double-servo system and method.

Background

The principle of online thickness detection is to convert the thickness measurement according to the energy attenuation when the X-ray penetrates the measured object, namely, to measure the X-ray absorbed by the measured object, and to determine the thickness of the measured object according to the energy value of the X-ray. The received energy signal is converted into an electric signal by the X-ray probe, amplified by the preamplifier and converted into an actual thickness signal which is displayed to people by the special thickness gauge processing system.

At present, the most common application in the on-line thickness detector is an O-shaped scanning frame structure, and the O-shaped scanning frame structure is generally formed by welding an upper beam and a lower beam with two side wall plates. The guide rails are respectively arranged on the upper beam and the lower beam and drive the upper probe and the lower probe to synchronously and reciprocally scan. In order to guarantee the consistency of the upper probe and the lower probe in the walking process, a set of spindle mechanism is inevitably arranged, the power of the motor is respectively transmitted to the up-and-down movement mechanism, and meanwhile, in order to guarantee the movement precision, the whole frame can be usually abnormally solid, the overall structure is complex, and the volume is large.

The specification with the publication number of CN206724911U discloses an X ray thickness gauge of low-cost short manufacturing cycle type, including frame and electric cabinet, last probe, lower probe, drive assembly, the gliding upward slide module of probe and the gliding lower slip module of probe under the cooperation of cooperation on the cooperation including setting up in the frame, the frame includes two stands, sets up last supporting beam and the bottom suspension crossbeam between two stands, goes up the probe and installs on last supporting beam, and lower probe is installed on the bottom suspension crossbeam, stand, last supporting beam and bottom suspension crossbeam are the assembly aluminium alloy, the both ends of going up supporting beam and bottom suspension crossbeam all splice on two stands. The utility model discloses a stand and the crossbeam of assembling the aluminium alloy replace original steel construction frame, and the cost of manufacture is low to the on-the-spot installation space requirement harsher, has the shortcoming of the unable installation of some occasions.

The specification with publication number CN102564361A discloses a ray type thickness gauge and a correction method thereof, wherein the thickness gauge comprises a ray source, a ray detector, a preamplification circuit board, a control cabinet, a terminal display and operation device and a C-shaped frame; the radiation source is arranged at the lower part of the throat gap of the C-shaped frame, the radiation detector is arranged at the upper part of the throat gap of the C-shaped frame, the metal strip to be detected passes through the throat gap of the C-shaped frame, the preamplification circuit board is connected with the control cabinet, and the control cabinet is connected with the terminal display and operation device and is used for calculating and displaying the thickness and receiving the instruction of an operator. The invention mainly provides a thickness measurement value for a rolling mill thickness control system, thereby improving the production efficiency of the rolling mill and ensuring the tolerance requirement of rolled metal strips.

Disclosure of Invention

The invention aims to provide an online thickness detection double-servo system and method, which overcome the problems of double-probe mechanical linkage scanning in an online thickness detection system, optimize the structure of a detection scanning system through double-probe independent control and improve the accuracy of ray thickness measurement.

An online thickness detection dual servo system comprising: the probe comprises a control module, a guide mechanism and a pair of mutually matched probes, wherein the guide mechanism comprises a main moving frame and a secondary moving frame which are arranged in parallel, and the pair of probes are respectively fixed on the main moving frame and the secondary moving frame; the main moving frame and the auxiliary moving frame are respectively driven by a servo motor with a driver; the control module outputs pulses to the driver, and the driver controls the servo motor to enable the main moving frame and the auxiliary moving frame to synchronously move; meanwhile, the servo motor feeds back a coding signal to the control module for monitoring the positions of the main moving frame and the auxiliary moving frame in real time; and zero signal sensors for resetting the pair of probes are respectively fixed on the guide mechanisms.

When the measured object is used for measuring the thickness, the measured object passes through the pair of probes, and the main moving frame and the auxiliary moving frame run independently, so that the control module ensures that the main moving frame and the auxiliary moving frame run simultaneously, namely that the pair of probes fixed on the main moving frame and the auxiliary moving frame run simultaneously. When the thickness of a measured object is measured, the main moving frame and the auxiliary moving frame are respectively driven by a servo motor, and the control module outputs pulses to drivers respectively controlling the servo motors so that the servo motors drive the main moving frame and the auxiliary moving frame to synchronously walk; meanwhile, the servo motor feeds back a coding signal to the control module, and the main moving frame and the auxiliary moving frame are ensured to synchronously walk within a specified error range.

The guide mechanism is a pair of linear guide rail mechanisms arranged in parallel; the main moving frame is arranged on the main guide rail in a sliding mode, the auxiliary moving frame is arranged on the auxiliary guide rail in a sliding mode, and the main guide rail and the auxiliary guide rail are respectively fixed with a zero signal sensor. The linear guide rail mechanism is adopted, so that the scanning system has high motion precision and sensitivity and small friction coefficient.

The main guide rail and the auxiliary guide rail are both fixed with a reverse limit photoelectric sensor and a positive limit photoelectric sensor. The arrangement of the reverse limit photoelectric sensor and the positive limit photoelectric sensor limits the position limit of the pair of probes during operation, and prevents the probes from being impacted due to overtravel.

The distance between the zero signal sensor of the main guide rail and the anti-limiting photoelectric sensor is smaller than the distance between the zero signal sensor of the auxiliary guide rail and the anti-limiting photoelectric sensor, and the fact that the pair of probes are completely staggered is guaranteed.

The invention also provides a method adopted by the double-servo system based on the online thickness detection, which comprises the following steps:

(1) the control module drives the main servo motor and the slave servo motor to operate through the main driver and the slave driver, so that the main moving frame and the slave moving frame walk in opposite directions to reach zero positions;

(2) keeping the slave driver stopped, and enabling the main driver to operate to drive the main moving frame to move forwards by the main servo motor so as to enable the positions of the main moving frame and the slave moving frame to be staggered;

(3) the main driver operates to enable the main servo motor to drive the main moving frame to reversely walk to a zero position, the control module collects signals output by the probe in real time and collects coding position signals fed back by the main servo motor;

(4) the control module calculates the deviation distance of the zero positions corresponding to the main moving frame and the slave moving frame, and the main servo motor moves the position of the main moving frame by driving the main driver to compensate the deviation distance;

(5) The measured object passes through between a pair of probes, and control module passes through main driver and follows the driver and drives main servo motor and follow servo motor operation simultaneously, makes main removal frame and follow and removes the frame and carry out forward or reverse walking in step, and control module collects the signal of probe output in real time and measures the thickness of measured object.

In the step (1), the control module respectively controls the master driver and the slave driver by outputting pulse signals, and stops outputting corresponding pulse signals after the zero signal sensor detects that the master moving frame and the slave moving frame respectively reach zero positions, so that the master servo motor and the slave servo motor are stopped.

In the step (3), the control module converts the current signal fed back by the probe into a 16-bit digital value through the AD module of the control module and stores the 16-bit digital value into a temporary buffer; and meanwhile, orthogonal AB phase coded pulse signals fed back by the main servo motor are collected, a corresponding system position value is updated when one pulse signal changes, and a plurality of current signal digital values temporarily buffered and stored between two pulses are processed by adopting median filtering.

In the step (4), the control module stores the current signal digital value processed in the step (3) into a Y-axis memory array, and stores a real-time system position value into an X-axis memory array to form a two-dimensional curve until the main moving frame returns to a zero position, and the control module calculates the position corresponding to the maximum value of the output signal of the probe to obtain the deviation distance.

The X-axis memory array stores continuously changed position values of a main servo motor and a process from starting to stopping of the servo motor; the Y-axis memory array stores the digital values of the current signals corresponding to the X-axis.

Preferably, in the X-axisThe corresponding Y-axis array data is taken out from the continuous array, thenVariation of a continuous arrayComprises the following steps:

wherein the content of the first and second substances,is the X axisThe Y-axis array data corresponding to the array,is the X axisThe average value of Y-axis array data of the continuous arrays;

sequentially accumulating the X-axis array data to obtain the variation of the current continuous array; and finally, respectively obtaining two X-axis array data with the largest variation in the ascending section and the descending section of the X-axis array data, wherein the deviation distance of the pair of probes is the data intermediate value of the two X-axis array data with the largest variation.

In the step (5), the control module monitors feedback coding pulse signals of the master servo motor and the slave servo motor, and when the difference between the two pulse values exceeds a set difference value, the scanning system stops running and gives an alarm.

Compared with the prior art, the invention has the advantages that:

1. the invention reduces the mechanical synchronous transmission parts in the double-probe detection scanning system, greatly improves the installation flexibility of the detection scanning equipment, and is not limited by the limitation of field installation space.

2. The invention adopts double servo motors to control the synchronous precision, has strong adaptability and greatly improves the detection precision of the online thickness detection system.

Drawings

FIG. 1 is a schematic view of a guide mechanism mounted vertically in an embodiment of the present invention;

FIG. 2 is a schematic view of the structure of the guide mechanism installed in the horizontal direction in the embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a conventional O-gantry structure of a comparative example according to an embodiment of the present invention;

FIG. 4 is a graph of a lateral scan of the dual servo gantry of FIG. 1;

fig. 5 is a lateral scan graph of the conventional O-gantry structure shown in fig. 3.

Detailed Description

As shown in fig. 1 and 2, the online thickness detection dual servo system includes: the system comprises a control module, a guide mechanism and a pair of mutually matched probes 1, wherein the pair of probes 1 adopt X-ray probes, one probe is an X-ray emission probe 11, and the other probe is an X-ray receiving probe 12.

The guide mechanism comprises a main moving frame 21 and a secondary moving frame 31 which are arranged in parallel, and the X-ray receiving probe 12 and the X-ray emitting probe 11 are respectively fixed on the main moving frame 21 and the secondary moving frame 31; the master moving frame 21 and the slave moving frame 31 are respectively driven by servo motors with drivers; the servo motors include a master servo motor 22 and a slave servo motor 32, and the control module drives the master servo motor 22 and the slave servo motor 32 respectively by outputting pulses to the master driver and the slave driver (not shown in the figure). The main servo motor 22 and the slave servo motor 32 run to drive the main moving frame 21 and the slave moving frame 31 to move; meanwhile, the servo motor feeds back a coded signal to the control module, and the coded signal is used for monitoring the positions of the main moving frame 21 and the auxiliary moving frame 31 in real time; and zero point signal sensors for resetting the X-ray emission probe 11 and the X-ray receiving probe 12 are respectively fixed on the guide mechanism.

The guide mechanism is a pair of linear guide rail mechanisms arranged in parallel and comprises a main linear guide rail mechanism 2 and a slave linear guide rail mechanism 3; the main linear guide rail mechanism 2 comprises a main guide rail 23, and the main moving frame 21 is arranged on the main guide rail 23 in a sliding manner; the slave linear guide mechanism 3 includes a slave guide 33, and the slave moving frame 31 is slidably provided on the slave guide 33, and zero point signal sensors are fixed to the master guide 23 and the slave guide 33, respectively.

As shown in figure 1, the main linear guide rail mechanism 2 and the auxiliary linear guide rail mechanism 3 are arranged side by side up and down to meet the thickness measuring requirement when the detection piece moves horizontally.

As shown in fig. 2, the primary linear guide mechanism 2 and the secondary linear guide mechanism 3 are horizontally arranged side by side to meet the thickness measurement requirement when the detection member moves vertically.

The two ends of the main guide rail 23 and the auxiliary guide rail 33 are both fixed with a reverse limit photoelectric sensor and a positive limit photoelectric sensor.

The distance between the zero signal sensor of the main guide rail 23 and the anti-limit photosensor is smaller than the distance between the zero signal sensor of the sub guide rail 33 and the anti-limit photosensor.

The method for detecting the double servo systems based on the online thickness in the embodiment comprises the following steps:

(1) the control module drives the main servo motor 22 and the slave servo motor 32 to run through the main driver and the slave driver, so that the main moving frame 21 and the slave moving frame 31 walk in reverse directions to reach zero positions;

(2) Keeping the slave driver stopped, the main driver operates the main servo motor 22 to drive the main moving frame 21 to move forward, and the positions of the main moving frame 21 and the slave moving frame 31 are staggered;

(3) the main driver operates to enable the main servo motor 22 to drive the main moving frame 21 to reversely walk to a zero position, the control module collects signals output by the X-ray receiving probe 12 in real time, and meanwhile, code position signals fed back by the main servo motor 22 are collected;

(4) the control module calculates the offset distance of the zero positions corresponding to the main moving frame 21 and the slave moving frame 31, and drives the main driver to enable the main servo motor 22 to move the position of the main moving frame 21 so as to compensate the offset distance;

(5) the measured object passes through the space between the X-ray transmitting probe 11 and the X-ray receiving probe 12, the control module simultaneously drives the main servo motor 22 and the auxiliary servo motor 32 to run through the main driver and the auxiliary driver, so that the main moving frame 21 and the auxiliary moving frame 31 synchronously move forwards or backwards, and the control module collects signals output by the X-ray receiving probe 12 in real time to measure the thickness of the measured object.

The scanning method of the scanning system as exemplified in fig. 1 comprises the following steps:

and (2) performing the step (1), the control module respectively controls the master driver and the slave driver by outputting pulse signals, and stops corresponding pulse signal output after detecting that the master moving frame 21 and the slave moving frame 31 respectively reach zero positions through the zero signal sensor, so that the master servo motor 22 and the slave servo motor 32 respectively controlled by the master driver and the slave driver are stopped.

Step (2) is performed in which the slave driver is kept stopped, and the master driver operates to cause the master servo motor 22 to drive the master moving frame 21 to move in the forward direction so that the positions of the master moving frame 21 and the slave moving frame 31 are staggered with each other.

Step (3) is carried out, the control module converts the current signal fed back by the X-ray receiving probe 12 into a 16-bit digital value through the AD module of the control module and stores the digital value into a temporary buffer; and meanwhile, orthogonal AB phase coded pulse signals fed back by the main servo motor 22 are collected, and a corresponding system position value is updated every time one pulse signal is changed, and a plurality of current signal digital values temporarily buffered and stored between two pulses are processed by adopting median filtering.

And (4) storing the current signal digital value processed in the step (3) into a Y-axis memory array by the control module, storing a real-time system position value into an X-axis memory array to form a two-dimensional curve until the main moving frame 21 returns to a zero position, and calculating the position corresponding to the maximum value of the output signal of the X-ray receiving probe 12 by the control module to obtain the deviation distance.

The X-axis memory array stores the continuously changing position values of the main servo motor 22 and the process from the start to the stop of the servo motor 32; the Y-axis memory array stores the digital values of the current signals corresponding to the X-axis.

Taking out the corresponding Y-axis array data from the X-axis array No. 0 to No. 4, and changing the 5 continuous arraysComprises the following steps:

wherein the content of the first and second substances,is the X axisThe Y-axis array data corresponding to the array,the average value of Y-axis array data of 5 continuous arrays on the X axis;

sequentially accumulating the X-axis array data to obtain the variation of the current continuous array; and finally, respectively obtaining two X-axis array data with the largest variation in the ascending section and the descending section of the X-axis array data, wherein the deviation distance between the X-ray transmitting probe 11 and the X-ray receiving probe 12 is the data intermediate value of the two X-axis arrays with the largest variation.

And (5) passing the object to be detected between the X-ray transmitting probe 11 and the X-ray receiving probe 12, and simultaneously driving the main servo motor 22 and the auxiliary servo motor 32 to run by the control module through the main driver and the auxiliary driver so that the main moving frame 21 and the auxiliary moving frame 31 synchronously move forwards or backwards.

The X-ray emission probe 11 is internally provided with an X-ray source, after the X-ray source emits rays which pass through a measured object, the rays are emitted into an X-ray receiving probe 12 provided with an ionization chamber and an amplification plate, the X-ray receiving probe 12 linearly converts the energy of the rays into current signals through the ionization chamber and inputs the current signals into the amplification plate, and a 0-5V voltage signal is generated through a sampling resistor of the amplification plate and an operational amplifier circuit and output to the control module.

The AD module in the control module converts the input voltage signal into 16-bit digital data to be stored in the memory. The control module collects the voltage signal output by the X-ray receiving probe 12 in real time to measure the thickness of the measured object.

The ionization chamber is a current type ionization chamber and consists of electrodes with different potentials and a medium between the electrodes.

When no-load, the X-ray source outputs ray to irradiate downwards through the exit hole, at the same time, the ray only penetrates through air to reach the ionization chamber, and the ionization chamber and the amplifying plate convert the ray energy into no-load voltage signal。

In the continuous detection process, the object to be detected passes through the space between the X-ray source and the ionization chamber, the ray penetrates through the object to be detected, the ray absorbs a part of ray energy in the penetration process, and the ray intensity is weakened; at this time, the ionization chamber and the amplification plate convert and output the measurement voltageIn the continuous scanning detection processThe change is caused by the difference of the surface density of the measured object.

Due to the fact thatIf there is significant correlation with the areal density, the measured value of the areal density of the object is determinedComprises the following steps:

wherein the content of the first and second substances,in order to be able to take advantage of the absorption coefficient,is the translation coefficient;andall are obtained by calibrating the measured object with known areal density.

The control module monitors the feedback coding pulse signals of the master servo motor 22 and the slave servo motor 32, and when the difference between the two pulse values exceeds a set difference value, the scanning system stops running and gives an alarm.

And comparing the system precision of the online thickness detection double-servo system with the conventional O-shaped scanning frame structure:

the accuracy characteristics of the system can be verified by testing a relatively static object to be tested. The forward and reverse directions are continuously scanned once, and the smaller the deviation of the forward and reverse rows is, the better the repeatability and the higher the precision of the forward and reverse rows of the online thickness detection double-servo system are. The lateral deviation is the fluctuation of the data scanned in one direction, the smaller the value, the smaller the fluctuation, i.e. the stability of the lateral scanning data is good, if the fluctuation is large, the error generated by the measured value of the point is large.

The thickness of the copper foil was measured by taking about 54.2g as an example. An online thickness detection double-servo system is adopted, a copper foil is placed between an X-ray emission probe 11 and an X-ray receiving probe 12, 50 groups of data are obtained by continuously scanning forward and reverse once subareas, and 6 groups of data are measured, as shown in Table 1. An average value is respectively taken by the positive line and the negative line of 50 groups of data, and the difference value of the two average values is the positive line deviation and the negative line deviation, namely the difference value of the positive scanning and the negative scanning.

TABLE 1 Online thickness detection Dual Servo System continuous scanning thickness data

The same copper foil was placed between a pair of probes 1 of a conventional O-type scanning frame structure of the same specification, comparative testing was performed, 50 sets of data were obtained by continuously scanning the forward and reverse sub-regions at one time, and 6 sets of data were measured as shown in table 2. The conventional O-type scanning frame structure is shown in fig. 3, and the conventional O-type scanning frame structure includes a guide rail 4, and a pair of probes 1 performing synchronous reciprocating scanning motion on the guide rail 4 through a moving frame 5, where the pair of probes 1 includes an X-ray emitting probe 11 and an X-ray receiving probe 12, and the synchronous reciprocating scanning motion of the X-ray emitting probe 11 and the X-ray receiving probe 12 is realized by synchronously driving the moving frame 5 through a main shaft mechanism 6.

TABLE 2 continuous scanning thickness data for conventional O-gantry configuration

The forward and reverse deviation precision of the thickness detection system adopts the ratio of the forward and reverse deviation value to the quantitative gram weight, the forward and reverse deviation value of the online thickness detection dual-servo system is obtained through measurement, and as shown in table 3, the forward and reverse deviation precision of the online thickness detection dual-servo system is calculated to be 0.000802%; the forward and backward deviation values of the conventional O-shaped scanning frame structure are obtained through measurement, and as shown in table 4, the deviation precision of the conventional O-shaped scanning frame structure is 0.0223274%, so that the forward and backward precision of the online thickness detection dual-servo system is obviously improved.

TABLE 3 Online thickness detection precision calculation table with double servo systems

TABLE 4 calculation table for precision of conventional O-type scanning frame structure

The lateral deviation accuracy is the ratio of the lateral deviation to the quantitative grammage, and as shown in tables 3 and 4, the lateral deviation accuracy calculated by the scanning frame adopting the double servo is 0.05596%; the transverse deviation precision obtained by adopting the conventional O-shaped scanning frame is 0.13729%, so that the transverse deviation precision of the online thickness detection double-servo system is obviously improved.

As shown in fig. 4 and 5, the repeatability of the dual servo system for online thickness detection is higher than that of the conventional O-gantry, as can be obtained from the 6 sets of transverse scan curves for the dual servo gantry and conventional O-gantry configurations.

The following description is based on the on-line thickness detection of a raw foil machine as an example:

two servo of on-line thickness detection locate and give birth to between paper tinsel machine foil raising device and the pinch roll, with a pair of main linear guide mechanism 2 that are parallel to each other with follow linear guide mechanism 3 and be fixed in the upper beam and the underbeam of giving birth to the paper tinsel machine through the mounting bracket respectively, two servo of line thickness detection reset before detecting copper foil thickness earlier: the control module drives the main servo motor 22 and the slave servo motor 32 to run through the main driver and the slave driver, so that the main moving frame 21 and the slave moving frame 31 walk in reverse directions to reach zero positions; keeping the slave driver stopped, the main driver operates the main servo motor 22 to drive the main moving frame 21 to move forward, and the positions of the main moving frame 21 and the slave moving frame 31 are staggered; the main driver operates to enable the main servo motor 22 to drive the main moving frame 21 to reversely walk to a zero position, the control module collects signals output by the X-ray receiving probe 12 in real time, and meanwhile, code position signals fed back by the main servo motor 22 are collected; the control module calculates the offset distance between the zero positions corresponding to the main moving frame 21 and the slave moving frame 31, and drives the main driver to enable the main servo motor 22 to move the position of the main moving frame 21 so as to compensate the offset distance.

When the copper foil is output from the foil lifting device, the pinch roll pulls the copper foil to pass between the X-ray emission probe 11 and the X-ray receiving probe 12, the main moving frame 21 and the auxiliary moving frame 31 are independent from each other in walking, so that the control module ensures that the main moving frame 21 and the auxiliary moving frame 31 walk simultaneously, the control module drives the main servo motor 22 and the auxiliary servo motor 32 to run simultaneously through a main driver and an auxiliary driver, the main moving frame 21 and the auxiliary moving frame 31 synchronously walk forwards or backwards, and the control module collects signals output by the X-ray receiving probe 12 in real time to measure the thickness of a measured object; meanwhile, the control module monitors the feedback coding pulse signals of the master servo motor 22 and the slave servo motor 32 to ensure the synchronism of the master moving frame 21 and the slave moving frame 31.