CN102275132A

CN102275132A - Online measuring method of diameter of grinding wheel of high-force powerful shape-followup snagging machine

Info

Publication number: CN102275132A
Application number: CN2011100973623A
Authority: CN
Inventors: 李宛洲; 王京春; 康少栋; 杨博; 杨峰; 邹国斌
Original assignee: Tsinghua University
Current assignee: Tsinghua University
Priority date: 2011-04-19
Filing date: 2011-04-19
Publication date: 2011-12-14
Anticipated expiration: 2031-04-19
Also published as: CN102275132B

Abstract

The invention relates to an online measuring method of the diameter of a grinding wheel of high-speed powerful shape-followup snagging machine, belonging to the technical field of engineering measurement. The method comprises the following steps of: establishing a workpiece and grinding wheel diameter associated model through a motion mechanism model of the snagging machine and alternating shock vibration data analysis based on process statistics; acquiring high-precision grinding wheel diameter data with a simple measurement method by using a high-precision displacement measurement laser sensor under a large-vibration and strong-interference background; and correcting errors of the high-precision grinding wheel diameter data. According to the invention, a corresponding real-time data support is provided so as to realize the optimized grinding effect and reduce the grinding wheel loss.

Description

Online measuring method for diameter of grinding wheel of high-speed powerful shape following rough grinding machine tool

Technical Field

The invention belongs to the technical field of engineering measurement, and mainly relates to an online measuring method for the diameter of a grinding wheel of a high-speed powerful shape following rough grinding machine tool, which is applied to rough machining equipment in the metallurgical industry.

Background

A heavy high-speed powerful shape following rough grinding machine tool is rough machining equipment in the metallurgical industry, and grinding control optimization is established on the basis that all operation parameters can be obtained in real time, wherein the key point is to measure the diameter of a grinding wheel. The rough grinding machine has a severe working environment, and high-temperature and high-linear-speed grinding metal particles generated during high-speed grinding are injected all around, so that the diameter of the grinding wheel is very difficult to directly measure. The indirect measurement by using the laser sensor is a scheme, but the excircle of the grinding wheel is in a high-temperature red hot state during grinding, and a measuring point is printed on the grinding wheel by a common laser, so that a return signal sometimes does not exist or even cannot be received. The method is characterized in that a laser measuring point is positioned on the surface of a workpiece (a roller casting blank), and the diameter of the grinding wheel is obtained by utilizing the indirect calculation of the workpiece and a grinding wheel diameter correlation model. In addition, the surface of the workpiece is rough and uneven, the measured value of the laser sensor correspondingly fluctuates when the workpiece rotates, meanwhile, the grinding wheel is in direct contact with the workpiece, strong vibration is generated in the grinding process, a hydraulic piston supporting the cantilever also fluctuates up and down along with the strong vibration, and the measuring system also needs to consider reducing the interference.

Disclosure of Invention

The invention aims to measure and calculate the diameter of a grinding wheel in real time when a heavy high-speed powerful shape following rough grinding machine tool runs, and provide real-time data support for subsequent optimization of grinding control and reduction of grinding wheel loss.

The technical scheme of the invention is that a high-precision displacement measurement laser sensor is utilized, and on the basis of establishing a workpiece and grinding wheel diameter correlation model, high-precision grinding wheel diameter data are obtained by a simple measurement method under the background of large vibration. The method comprises the steps of equipment installation and communication, workpiece and grinding wheel diameter correlation model and error processing.

The method specifically comprises the following steps:

(1) hardware configuration and installation: a displacement measurement laser sensor is arranged below a support arm of the snagging machine, a level gauge is used for leveling the laser sensor, the light path of the laser sensor is perpendicular to the advancing direction of the trolley, and meanwhile, the light path of the laser sensor is positioned on one side of the vertical plane of the grinding wheel in the moving direction of the trolley in the horizontal direction and is as close to the vertical plane of the grinding wheel as possible. Fixing the laser sensor on the ground table base in the vertical direction;

(2) measuring parameters:

h is the vertical distance from the center of the cantilever rotating shaft to the center of the supporting roller,

x is the horizontal distance from the laser sensor to the center of the roller blank of the roller,

m is the horizontal distance from the rotating shaft at the bottom end of the hydraulic push rod to the center of the roller blank of the roller,

n is the vertical distance from the center of the supporting roller wheel to the rotating shaft at the bottom end of the hydraulic push rod,

Y₀when the hydraulic push rod piston is completely retracted, the distance between the rotating shafts at the two ends of the push rod is increased,

h is the vertical height from the center of the supporting roller to the measuring point of the laser sensor,

a-horizontal distance from the laser sensor to the surface of the closer support roller,

b-horizontal distance from the center of the roller blank to the center of the supporting roller,

r-radius of the supporting roller,

alpha is the included angle between the cantilever and the connecting line of the cantilever axis and the push rod top shaft,

c-the distance from the center of the cantilever rotating shaft to the center of the rotating shaft at the top end of the hydraulic push rod,

d is the distance from the center of the supporting shaft at the bottom end of the hydraulic push rod to the center of the cantilever rotating shaft,

l is the distance from the center of the cantilever rotating shaft to the center of the grinding wheel;

(3) data communication: the laser sensor is connected and communicated with an upper computer through an RS232 serial port, and an upper computer operation data acquisition program receives and stores data in real time; starting a laser range finder for debugging, and confirming that a laser measuring point is effective; testing the diameter of the roller blank, and comparing the diameter with a manual measured value to obtain an offset delta;

(4) calculating the diameter of the roller: by the formula

Calculating the theoretical diameter of the roller blank, wherein:

A＝4(h²-r²)

B＝4r[h²+b²-r²-(a+b+r-s)²]

C＝-[(a+b+r-s)²+r²+h²-b²]²-4h²(b²-r²)

in the formula, h is the vertical height from the center of the support roller to the measuring point of the laser sensor, phi is the diameter of the roller blank, R is the radius of the roller blank, a is the horizontal distance from the laser sensor to the surface of the closer support roller, b is the horizontal distance from the center of the roller blank to the center of the support roller, R is the radius of the support roller, and s is the distance from the laser sensor to the measuring point of the surface of the roller blank, namely the real-time measuring value of the laser sensor;

(5) calculating the diameter of the grinding wheel: when 4 conditions of grinding wheel starting rotation, positive pressure contact of the grinding wheel and the roller blank, roller blank rotation and axial feed of the roller blank are met, the diameter of the grinding wheel is updated and calculated. If any one of the conditions is not satisfied, the previous calculated value is maintained;

by the formula

Obtaining a theoretical value of the diameter of the grinding wheel, wherein:

<math><mrow> <mi>β</mi> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>c</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>-</mo> <msup> <mi>y</mi> <mn>2</mn> </msup> </mrow> <mrow> <mn>2</mn> <mi>cd</mi> </mrow> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow></math>

<math><mrow> <mi>γ</mi> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>f</mi> <mn>2</mn> </msup> <mo>-</mo> <msup> <mi>e</mi> <mn>2</mn> </msup> </mrow> <mrow> <mn>2</mn> <mi>df</mi> </mrow> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow></math>

y＝Y₀+ΔY，

e = \sqrt{M^{2} + {(N + \sqrt{{(R + r)}^{2} - b^{2}})}^{2}},

f = \sqrt{X^{2} + {(H - \sqrt{{(R + r)}^{2} - b^{2}})}^{2}},

wherein Rs is the radius of the grinding wheel, l is the distance from the center of the cantilever rotating shaft to the center of the grinding wheel, f is the distance from the center of the cantilever rotating shaft to the center of the roller blank of the roller, alpha is the included angle between the cantilever and the axis of the cantilever and the connecting line of the top shaft of the push rod, beta is the included angle between the connecting line of the axis of the cantilever and the top shaft of the push rod and the connecting line of the axis of the cantilever and the bottom shaft of the push rod, gamma is the included angle between the connecting line of the axis of the cantilever and the center of the roller blank and the axis of the cantilever and the bottom shaft of the push rod, c is the distance from the center of the cantilever rotating shaft to the center of the rotating shaft at the top end of the hydraulic push rod, the value is recorded by a push rod hydraulic numerical control system and can be called by a third party program, and e is the distance from the center of a support rotating shaft at the bottom end of the hydraulic push rod to the center of a roller blank;

(6) error analysis and processing: considering error factors, correcting a diameter calculation formula of the grinding wheel, wherein the corrected diameter calculation formula of the grinding wheel is as follows:

wherein,

A＝4(h²-r²)，

B′＝4r[h²+b²-r²-(a+b+r-s′)²]，

C′＝-[(a+b+r-s′)²+r²+h²-b²]²-4h²(b²-r²)，

s′＝s′|_t-1+K|_t-1(s-s′|_t-1)，

D′＝a+b+r-s′，

E′＝D′²+r²+h²-b²，

<math><mrow> <msup> <mi>β</mi> <mo>′</mo> </msup> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>c</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>-</mo> <msup> <mrow> <mo>(</mo> <mi>y</mi> <msub> <mo>|</mo> <mrow> <mi>t</mi> <mo>-</mo> <msub> <mi>T</mi> <mi>d</mi> </msub> </mrow> </msub> <mo>)</mo> </mrow> <mn>2</mn> </msup> </mrow> <mrow> <mn>2</mn> <mi>cd</mi> </mrow> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow></math>

T_{d} = \frac{m}{V_{a}},

<math><mrow> <msup> <mi>γ</mi> <mo>′</mo> </msup> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>f</mi> <mrow> <mo>′</mo> <mn>2</mn> </mrow> </msup> <mo>-</mo> <msup> <mi>e</mi> <mrow> <mo>′</mo> <mn>2</mn> </mrow> </msup> </mrow> <msup> <mrow> <mn>2</mn> <mi>df</mi> </mrow> <mo>′</mo> </msup> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow></math>

in the above formula, m is the horizontal distance from the laser sensor to the vertical plane of the grinding wheel, and V_aThe axial feeding speed of the roller blank is K, and the K is an equivalent error proportionality coefficient.

The range required by the laser sensor is 0.2-70 m, the precision is +/-1 mm, and the frequency is not more than 10 Hz.

The data acquisition program can be used for carrying out system display setting, serial port communication setting and parameter setting of the working mode of the laser sensor.

The invention has the beneficial effects that:

(1) establishing a precise geometric positioning relation for a specific rough grinding machine tool, so that the field data can still be correctly transformed to the diameter correlation model parameters of the workpiece and the grinding wheel under the condition that a laser measuring point does not pass through the center of a roll blank, and the diameter of the roll blank, which is an intermediate quantity, is obtained by utilizing the laser ranging value and other related static variables; and the theoretical value of the diameter of the grinding wheel is deduced by utilizing the position data of the piston of the cantilever support rod of the grinding wheel, and meanwhile, a roll blank diameter correction link is added in the calculation process.

(2) The high-precision displacement measurement laser sensor is used, high-precision grinding wheel diameter data are obtained by a simple measurement method under the background of large vibration and strong interference, and real-time data support is provided for subsequent grinding optimization including online precise measurement of grinding quantity and the like and reduction of grinding wheel loss.

(3) An effective error processing method is provided, and the time delay and equivalent error proportional coefficient that the roller blank defects pass through a grinding wheel and a laser measuring point at different times are utilized, and after the laser ranging value and the piston position are processed in a related manner, the error fluctuation of the laser ranging value and the piston position is effectively cancelled in the calculation process, so that the error fluctuation of the diameter of the grinding wheel is reduced; meanwhile, vibration data in the grinding process are filtered, and the measurement error is effectively reduced.

Drawings

FIG. 1 is a schematic diagram of a grinder size and laser sensor installation;

FIG. 2 is a schematic diagram of the relative position geometry of the roll blank and the laser sensor;

FIG. 3 is a calculated roll blank diameter curve;

FIG. 4 is a schematic view showing the geometrical relationship between the grinding wheel and the roller blank;

FIG. 5 is a graph showing a trend of the position of the cantilever strut piston;

FIG. 6 is a schematic diagram showing the effect of roll blank surface defects on grinding wheel diameter calculation;

FIG. 7 is a schematic diagram of an error handling method according to the present embodiment;

FIG. 8 is a graph illustrating calculation of the equivalent error scaling factor K;

FIG. 9 is a trend curve of the equivalent error proportionality coefficient K;

FIG. 10 is a graph of calculated wheel diameters.

Reference numbers in the figures:

1-a laser sensor; 2-grinding wheel; 3-rolling a blank; 4-supporting arm of the snagging machine.

Detailed Description

The invention provides a method for measuring the diameter of a grinding wheel of a high-speed powerful shape following rough grinding machine on line, which is further explained by combining the attached drawings and the detailed implementation mode.

The method comprises the following specific steps:

1) hardware configuration and installation: based on the specifications of the rough grinding machine and the field production environment, the laser sensor has corresponding requirements on various indexes of the laser sensor, wherein the most important is the range, the precision, the frequency and the stability. The scheme selects a domestic laser displacement sensor, the measuring range is 0.2-70 m, the precision reaches +/-1 mm, and the frequency can reach 10Hz at most.

The high-precision displacement measurement laser sensor 1 is arranged below the support arm 4 of the snagging machine, thereby avoiding sparks splashing around during grinding and avoiding error increase caused by too long distance. Leveling the laser sensor by using a level gauge, and enabling the light path of the sensor to be perpendicular to the traveling direction of the trolley. Meanwhile, the light path of the laser sensor is positioned on the same side of the vertical plane of the grinding wheel in the moving direction of the trolley in the horizontal direction and is close to the vertical plane of the grinding wheel as much as possible so as to reduce the hysteresis of measured data, and the laser sensor is fixed on a ground table base in the vertical direction so as to reduce vibration, as shown in figure 1.

2) Measuring parameters: the following parameters and the roll body diameter of the roll blank 3 to be ground were measured manually, as shown in fig. 2, 3 and 5:

r-radius of the supporting roller,

l is the distance from the center of the cantilever rotating shaft to the center of the grinding wheel.

3) Data communication: the electric lines of the laser sensor are connected well and comprise a power line and an RS232 serial port data line. After the diameter of the roller body of the roller blank to be grinded is manually measured, the roller body is moved into a working position. And starting the laser range finder for debugging, and confirming that the laser measuring point is effective.

The laser sensor is communicated with the upper computer through an RS232 serial port, and the upper computer runs a data acquisition program which is independently developed to receive and store data in real time. The program supports all setup functions for the sensor based on the Microsoft Visual C # language. And opening a setting interface to perform system display setting, serial port communication setting and parameter setting of the working mode of the laser sensor. The roll blank diameter is tested and compared with the manually measured value to obtain the offset delta.

4) Calculating the diameter of the roller: the relative positions of the grinder structure and the laser sensor shown in fig. 1 are abstracted into the geometric relationship shown in fig. 3, and variables in the diagram except R can be obtained by machine tool design size or field measurement.

According to the plane geometry knowledge, there are:

{(h - \sqrt{R^{2} - {[(a + b + r) - s]}^{2}})}^{2} + b^{2} = {(R + r)}^{2} - - - (1)

unfolding to obtain:

4R²(h²-r²)+4rR[h²+b²-r²-(a+b+r-s)²]

(2)

-[(a+b+r-s)²+r²+h²-b²]²-4h²(b²-r²)＝0

wherein h is the vertical height from the center of the supporting roller to the measuring point of the laser sensor, R is the radius of the roller blank, a is the horizontal distance from the laser sensor to the surface of the supporting roller which is closer, b is the horizontal distance from the center of the roller blank to the center of the supporting roller, R is the radius of the supporting roller, and s is the distance from the laser sensor to the measuring point of the surface of the roller blank, namely the real-time measuring value of the laser sensor.

Order:

A＝4(h²-r²)

B＝4r[h²+b²-r²-(a+b+r-s)²](3)

C＝-[(a+b+r-s)²+r²+h²-b²]²-4h²(b²-r²)

comprises the following steps:

the theoretical diameter of the roll blank can be obtained, and a certain offset is required to be added due to the inevitable systematic error in the field. After the measuring device is fixed, the roll diameter is statically measured by using a laser sensor before starting, and the obtained result is compared with the roll diameter manually measured before grinding to obtain the offset delta. Thus, the calculation formula of the roll blank diameter is as follows:

the trend of the change in the roll blank diameter is shown in fig. 4.

5) Calculating the diameter of the grinding wheel: when the snagging machine performs the grinding process, the grinding wheel 2 is in close contact with the roll blank 3, and the geometrical relationship of the relative positions thereof is as shown in fig. 5. According to the plane geometry, there are:

e^{2} = M^{2} + {(N + \sqrt{{(R + r)}^{2} - b^{2}})}^{2}

f^{2} = X^{2} + {(H - \sqrt{{(R = r)}^{2} - b^{2}})}^{2}

y＝Y₀+ΔY

(R+R_s)²＝l²+f²-2lfcos(α+β-γ)

wherein l is the distance from the center of a cantilever rotating shaft to the center of a grinding wheel, c is the distance from the center of the cantilever rotating shaft to the center of a rotating shaft at the top end of a hydraulic push rod, d is the distance from the center of a support shaft at the bottom end of the hydraulic push rod to the center of the cantilever rotating shaft, y is the distance between the center of the rotating shaft at the top end of the hydraulic push rod and the center of a roller blank, e is the distance from the center of the support shaft at the bottom end of the hydraulic push rod to the center of the roller blank, f is the distance from the center of the cantilever rotating shaft to the center of the roller blank, alpha is the included angle between the cantilever and the connecting line of the cantilever shaft center and the top shaft of the push rod, beta is the included angle between the connecting line of the cantilever shaft. Y is the dynamic distance between the two ends of the hydraulic push rod to support the rotating shaft, and delta Y is the real-time position of the piston of the hydraulic cylinder in the push rod, and the position of the piston is automatically recorded and stored by the Archives function of ProTool and can be called by a third party program. The Protool is HMI (Human Machine Interface) software integrated in Siemens PLC (Programmable Logic Controller) programming configuration software STEP7, and the support rod hydraulic control in the system adopts Siemens SINUMERIK 840D numerical control system which is integrated with the PLC of Siemens S7-300-2 DP.

The theoretical value of the grinding wheel diameter can be obtained by the method:

in practical application, the laser should be installed on one side of the control console of the rough grinding machine tool to ensure that the laser measuring point always irradiates the ground surface and waste materials generated in the grinding process cannot damage the laser sensor. When 4 conditions of grinding wheel starting rotation, positive pressure contact of the grinding wheel and the roller blank, roller blank rotation and axial feed of the roller blank are met, the diameter of the grinding wheel is updated and calculated. If any one of the conditions is not satisfied, the previous calculated value is maintained.

6) Error analysis and processing: when grinding a workpiece, the reduction of the actual diameter of the grinding wheel should be a smooth gradual process. In the calculation process, if errors are not processed, the errors are directly calculated, and due to the influence of vibration of the cantilever and rough surface of the roller blank, the laser distance measurement value and the position value of the cantilever supporting rod piston can fluctuate frequently, and the laser distance measurement value and the position value are both dynamic variables involved in the calculation process, so that the diameter of the obtained grinding wheel fluctuates greatly.

Surface defects formed during casting of the rolled steel billet, such as raised steel ladle sand, cannot be flattened once when the rolled steel billet is ground by a snagging machine, particularly obvious projections. Therefore, when the grinding wheel passes through the bulge every time, the cantilever and the hydraulic push rod are driven, and the fluctuation of the position data of the piston is caused. Taking a single defect as an example, in the case shown in fig. 7(a), the convex hull is jacked up when passing through the grinding wheel, at this time, the distance measurement of the laser does not change significantly, it can be known that the roll diameter calculated by the distance measurement does not change significantly, and the diameter of the grinding wheel calculated according to the geometric constraint relationship is shown by a dotted line in the left figure, and the error caused by this case is approximately equal to the convex height of the ladle. The second situation is shown in fig. 7(b), when the ladle rotates to a laser measuring point, the distance measuring value of the laser changes obviously, the roller diameter calculated by the distance measuring value is shown by a lower dotted line circle, at this time, the hydraulic push rod does not change obviously, the diameter of the grinding wheel calculated according to the geometric constraint relation is shown by an upper dotted line circle, the radius error of the grinding wheel caused by the diameter change is generally different from the height of the bulge, and the difference depends on the distance of the measuring light path deviating from the center of the roller blank.

The invention provides a processing method capable of effectively reducing errors. Due to the limitation of the structure of the support arm of the snagging machine and the surrounding environment, the laser sensor cannot be placed on the same vertical plane with the grinding wheel, but is offset to the side to a certain extent and is set as m; meanwhile, due to the change of the diameter of the roller blank, the laser cannot always pass through the circle center, and the relative position relationship of the grinding wheel, the roller blank and the laser measuring point during grinding is shown in fig. 8. The roller blank is axially fed while being tangentially rotated, and the linear speed of the tangential rotation is much higher than the axial feeding speed. Thus, in roll grinding, if a projection passes through the grinding wheel, it must pass through the laser measurement point after a certain time delay. Setting the rotating linear speed of the roller body as V_tAxial feed speed V_aIf both of these variables are in the stored variable list of the 840D numerical control program, the time difference between the protrusion passing through the grinding wheel and the laser measuring point is:

T_{d} = \frac{m}{V_{a}} - - - (8)

advancing the current data of hydraulic piston position by T_dThe time-derived values are exactly matched to the current laser measurement point data, and the grinding wheel diameter calculated therefrom has a T_dThe time delay of the length is acceptable in view of the small value of the offset m, the considerable feeding speed of the roller blank and the slow reduction of the diameter of the grinding wheel.

In addition, the grinding wheel radius errors caused when the convex hull passes through the laser measuring point and the grinding wheel are not always the same, so that the fluctuation of the laser ranging data needs to be scaled, and the product of the fluctuation is equivalent to the grinding wheel radius error caused when the original convex hull passes through the grinding wheel after being multiplied by a proportionality coefficient K, wherein K is called an equivalent error proportionality coefficient. Therefore, data fluctuation of laser ranging and data fluctuation of the position of the piston can be better counteracted, and calculation error of the diameter of the grinding wheel is reduced. As shown in FIG. 9, when a ladle sand with an actual height p rotates to a laser measuring point, the ladle sand is scaled to delta s by a proportionality coefficient K, and the outer diameter of the roll blank calculated by the scaling factor K is just equal to T_dThe theoretical roller diameters under the constraint relation are equal when the ladle sand passes through the grinding wheel before the moment, and the diameter of the grinding wheel calculated from the theoretical roller diameters is closer to the true value.

Wherein p is the actual height of the sand-in-steel bulge, z is the height from the top of the roller blank to the plane of the supporting roller shaft, and the relationship between the height and the radius R of the roller blank is as follows:

z = \sqrt{{(R + r)}^{2} - b^{2}} + R

\frac{dz}{dR} = \frac{R + r}{\sqrt{{(R + r)}^{2} - b^{2}}} + 1 - - - (10)

further derivation, let:

D＝a+b+r-s

(11)

E＝D²+r²+h²-b²

comprises the following steps:

K = - \frac{ds}{dR} \frac{dR}{dz} = \frac{A}{4 D} \frac{1}{r - \frac{rB - AE}{\sqrt{B^{2} - 4 AC}}} \frac{1}{\frac{R + r}{\sqrt{{(R + r)}^{2} - b^{2}}} + 1} - - - (12)

substituting the data yields the K-line trend as shown in fig. 10. The calculation formula of the corrected diameter of the grinding wheel is as follows:

wherein,

A＝4(h²-r²)，

B′＝4r[h²+b²-r²-(a+b+r-s′)²]，

C′＝-[(a+b+r-s′)²+r²+h²-b²]²-4h²(b²-r²)，

s′＝s′|_t-1+K|_t-1(s-s′|_t-1)，

D′＝a+b+r-s′，

E′＝D′²+r²+h²-b²，

T_{d} = \frac{m}{V_{a}},

the calculated change trend of the diameter of the grinding wheel is shown in fig. 10, wherein the upper graph is the result after error correction, and the lower graph is the result after error correction and after moving average filtering with n being 10, it can be seen that the diameter of the grinding wheel is gradually reduced along with the grinding, and the numerical value of the diameter of the grinding wheel is also consistent with the actual value through field verification.

Claims

1. The method for measuring the diameter of the grinding wheel of the high-speed powerful shape following rough grinding machine tool on line is characterized by comprising the following steps of:

(1) hardware configuration and installation: a displacement measurement laser sensor is arranged below a support arm of the snagging machine, a level gauge is used for leveling the laser sensor, the light path of the laser sensor is perpendicular to the advancing direction of the trolley, meanwhile, the light path of the laser sensor is positioned on one side of the vertical plane of the grinding wheel in the same trolley moving direction in the horizontal direction and is close to the vertical plane of the grinding wheel as much as possible, and the laser sensor is fixed on a ground platform base in the vertical direction;

(2) measuring parameters:

r-radius of the supporting roller,

(4) calculating the diameter of the roller: by the formula

Calculating the theoretical diameter of the roller blank, wherein:

A＝4(h²-r²)

B＝4r[h²+b²-r²-(a+b+r-s)²]

C＝-[(a+b+r-s)²+r²+h²-b²]²-4h²(b²-r²)

(5) calculating the diameter of the grinding wheel: when 4 conditions of grinding wheel starting rotation, grinding wheel positive pressure contact with roller blank, roller blank rotation and roller blank axial feeding are met, updating calculation of the diameter of the grinding wheel is carried out, and under the condition that any one condition is not met, the former calculation value is kept;

by the formula

Obtaining a theoretical value of the diameter of the grinding wheel, wherein:

<math> <mrow> <mi>β</mi> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>c</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>-</mo> <msup> <mi>y</mi> <mn>2</mn> </msup> </mrow> <mrow> <mn>2</mn> <mi>cd</mi> </mrow> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow> </math>

<math> <mrow> <mi>γ</mi> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>f</mi> <mn>2</mn> </msup> <mo>-</mo> <msup> <mi>e</mi> <mn>2</mn> </msup> </mrow> <mrow> <mn>2</mn> <mi>df</mi> </mrow> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow> </math>

y＝Y₀+ΔY，

e = \sqrt{M^{2} + {(N + \sqrt{{(R + r)}^{2} - b^{2}})}^{2}},

f = \sqrt{X^{2} + {(H - \sqrt{{(R + r)}^{2} - b^{2}})}^{2}},

wherein,

A＝4(h²-r²)，

B′＝4r[h²+b²-r²-(a+b+r-s′)²]，

C′＝-[(a+b+r-s′)²+r²+h²-b²]²-4h²(b²-r²)，

s′＝s′|_t-1+K|_t-1(s-s′|_t-1)，

D′＝a+b+r-s′，

E′＝D′²+r²+h²-b²，

<math> <mrow> <msup> <mi>β</mi> <mo>′</mo> </msup> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>c</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>-</mo> <msup> <mrow> <mo>(</mo> <mi>y</mi> <msub> <mo>|</mo> <mrow> <mi>t</mi> <mo>-</mo> <msub> <mi>T</mi> <mi>d</mi> </msub> </mrow> </msub> <mo>)</mo> </mrow> <mn>2</mn> </msup> </mrow> <mrow> <mn>2</mn> <mi>cd</mi> </mrow> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow> </math>

y＝Y₀+ΔY，

T_{d} = \frac{m}{V_{a}},

<math> <mrow> <msup> <mi>γ</mi> <mo>′</mo> </msup> <mo>=</mo> <mi>arccos</mi> <mrow> <mo>(</mo> <mfrac> <mrow> <msup> <mi>d</mi> <mn>2</mn> </msup> <mo>+</mo> <msup> <mi>f</mi> <mrow> <mo>′</mo> <mn>2</mn> </mrow> </msup> <mo>-</mo> <msup> <mi>e</mi> <mrow> <mo>′</mo> <mn>2</mn> </mrow> </msup> </mrow> <msup> <mrow> <mn>2</mn> <mi>df</mi> </mrow> <mo>′</mo> </msup> </mfrac> <mo>)</mo> </mrow> <mo>,</mo> </mrow> </math>

2. The method for measuring the diameter of the grinding wheel of the high-speed strong conformal rough grinding machine tool according to claim 1, wherein the range required by the laser sensor is 0.2-70 m, the precision is +/-1 mm, and the frequency is not more than 10 Hz.

3. The method for on-line measurement of the diameter of the grinding wheel of the high-speed strong conformal rough grinding machine tool according to claim 1, wherein the data acquisition program can perform system display setting, serial communication setting and parameter setting of the working mode of the laser sensor.