CN115854946A - Sawtooth image pickup device applied to automatic circular saw blade tooth grinding machine and application method thereof - Google Patents

Abstract

The invention relates to a sawtooth camera device applied to an automatic gear grinding machine for circular saw blades and a method for using the device. Pipe, high-pressure blowing pipe, connecting rod, return spring and positioning coil; when in use, install the two sets of devices on both sides of the grinding wheel, and work according to the following process: sawtooth shooting and parameter calculation, sawtooth wear calculation, sawtooth parameter selection Evaluation, sawtooth parameter optimization, sawtooth grinding accuracy verification, saw blade flatness evaluation. The device of the present invention has the characteristics of high reliability of liquid discharge work, no damage to the saw blade, simple and stable structure, and good popularization. The ability of degree detection; installing the device of the present invention on the automatic gear grinding machine and using the method of the present invention can greatly enhance the grinding accuracy and intelligence of the automatic gear grinding machine.

Description

Sawtooth Camera Applied to Circular Saw Blade Automatic Grinding Machine and Its Application Method

technical field

The invention relates to a sawtooth camera device, in particular to a sawtooth camera device applied to a circular saw blade automatic gear grinding machine and a use method thereof.

Background technique

In the actual work of the manufacturing industry, it is often necessary to cut plates, cast iron, glass, stone, plastics and other materials. The cutting process is the same as the turning, milling, planing, grinding, clamping and other processes, which is the basic operation of the manufacturing industry. Circular saw blades ("saw blades" for short) are commonly used tools in the cutting process. The saw blade consists of a central base and outer teeth. When working, the saw blade rotates at high speed, and then cuts the material through the saw teeth on the edge of the saw blade.

The automatic gear grinding machine is a common equipment in the industry related to the production and use of circular saw blades. It can use the grinding wheel as a grinding tool to process the tooth shape of the saw blade. The gear grinding machine is accompanied by the whole life cycle of the saw blade: when the saw blade is produced, the last process is to open the teeth, that is, to grind the saw teeth of a certain shape on the edge of the saw blade; after the saw blade is used for a period of time, the saw teeth on the edge of the saw blade It will become blunt. At this time, an automatic gear grinding machine is required to grind the sawtooth to keep the sawtooth sharp.

There are many kinds of sawtooth shapes of circular saw blades, including arc teeth, wolf teeth, triangular teeth, high and low teeth, chamfered teeth and so on. The sawtooth parameters of each sawtooth shape are very important, because the sawtooth parameters are directly related to performance indicators such as saw blade life, cutting efficiency, cutting accuracy, and cutting energy consumption.

The automatic gear grinding machines currently on the market cannot perform online real-time detection of the tooth shape parameters during the saw tooth grinding process: due to the large amount of heat emitted during the saw tooth grinding process, in order to avoid damage to the circular saw blade due to the high temperature caused by heat, it is usually used Cooling fluid such as saponin liquid dissipates heat, so a large amount of cooling fluid will be covered or left on the circular saw blade during the grinding process, resulting in the inability of laser, image and other detection methods to accurately detect the zigzag parameters. The current conventional practice is to disassemble the circular saw blade after the saw teeth have been ground, and then use tools such as image detectors and three-coordinate measuring instruments for off-line measurement.

Since the online real-time detection of the sawtooth shape parameters cannot be performed, the sawtooth grinding process of the automatic gear grinding machine cannot form a closed-loop feedback control, which means that the automatic gear grinding machine cannot be self-adapted according to the actual situation of the circular saw blade Grinding adjustment (such as adjusting the amount of grinding feed, grinding feed speed, etc.), so it is impossible to guarantee the accuracy of saw teeth grinding.

Contents of the invention

In order to overcome the deficiencies in the prior art, the present invention provides a sawtooth camera device and its usage method applied to circular saw blade automatic grinding machines. The device can identify sawtooth parameters online through sawtooth photography and image processing, and the The device is designed with a triple liquid drainage structure to exclude coolant from entering the sawtooth area to be photographed, thereby ensuring the accuracy of sawtooth parameter detection.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A sawtooth camera device applied to a circular saw blade automatic gear grinding machine, the sawtooth camera device includes a high-pressure air cavity, a circumferential air curtain block, a bead hole for a supplementary light, a camera fixing through hole, a vacuum extraction tube, and a high-pressure air blowing tube , a connecting rod, a return spring and a positioning coil, the high-pressure air chamber communicates with the circumferential air curtain block, the camera fixing through hole is arranged at the center of the high-pressure air chamber and the circumferential air curtain block, and the supplementary light The bead hole is located at the bottom of the circumferential air curtain block; the vacuum extraction pipe and the high-pressure air blowing pipe run through the high-pressure air cavity and the circumferential air curtain block, and are respectively installed on both sides of the fixed through hole of the camera; the connecting rod is arranged in the high-pressure air cavity Above the body, the two ends of the connecting rod are respectively fixed with the fixed vacuum extraction tube and the high-pressure blowing tube through interference fit; the return spring is installed in the upper cavity wall of the high-pressure gas cavity and is coaxially installed with the vacuum extraction tube; the positioning coil Installed in the upper cavity wall of the high-pressure gas chamber, and coaxially installed with the high-pressure blowing pipe;

An annular cavity surrounding the fixed through hole of the camera is set in the center of the high-pressure air cavity, and an air intake hole is respectively set on the two side walls of the high-pressure gas cavity; There are several cylindrical through-holes distributed around the periphery of the hole, and the cylindrical through-holes communicate with the annular cavity of the high-pressure gas chamber; an annular through-hole is opened in the lower half of the circumferential air curtain block, and the cross-section of the annular through-hole is an inclined structure.

Preferably, the high-pressure air cavity and the circumferential air curtain block are two cylinders with the same bottom diameter, and the two are installed coaxially.

Preferably, the bead holes of the supplementary light are arranged on the bottom surface of the circumferential air curtain block, and are evenly distributed around the outside of the circumference of the camera fixing through hole.

Preferably, the bottom of the high-pressure blowing pipe is 0.5 mm to 1 mm higher than the bottom of the vacuum extraction pipe.

Preferably, a layer of metal outer tube is sheathed on the outside of the high-pressure blowing tube corresponding to the positioning coil, and the height of the metal outer tube is equal to that of the positioning coil.

As a preference, an extraction port is provided at the bottom of the vacuum extraction tube, the profile of the extraction port is stepped, and the extraction port includes a first step line and a second step line, the width of the first step line and the second step line are equal; the second step line The width of the first step line and the second step line is 1 mm to 3 mm.

The present invention also provides a method for using the above-mentioned sawtooth camera device applied to a circular saw blade automatic grinding machine. Two sets of sawtooth camera devices are respectively installed on both sides of the grinding wheel, and work according to the following procedures: sawtooth photography and parameter calculation, sawtooth camera Wear calculation, sawtooth parameter selection evaluation, sawtooth parameter optimization, sawtooth grinding accuracy verification, saw blade flatness evaluation;

Sawtooth shooting and parameter calculation: including shooting and tooth shape parameter calculation of the sawtooth before and after grinding, the tooth shape parameter calculation process includes sawtooth edge recognition, sawtooth feature point extraction, and sawtooth parameter calculation;

Sawtooth wear calculation: Subtract the standard tooth shape from the tooth shape before grinding to calculate the wear value of the three parameters of the front angle, rear angle and tooth back of the saw tooth before grinding;

Sawtooth parameter selection evaluation: use the support vector machine SVM model, take the three parameters of front angle average wear value, rear angle average wear value, and tooth back average wear value as the input parameters of the SVM model, and properly select the sawtooth parameter, sawtooth parameter Inappropriate selection as the output parameter of the SVM model, in order to judge whether the sawtooth parameters are suitable for the working conditions of the saw blade;

Sawtooth parameter optimization: adjust the average wear value of the front angle, the average wear value of the rear angle, and the average wear value of the tooth back of the tooth shape parameters to be ground;

Sawtooth grinding accuracy verification: subtract the standard tooth shape from the tooth shape after grinding to calculate the grinding error of the tooth shape parameters;

Saw blade flatness evaluation: According to the two parameters of tooth width and tooth depth after grinding, calculate the flatness of different teeth on the same saw blade after grinding, and then judge whether the saw blade after grinding is qualified.

As preferably, sawtooth edge recognition, uses the algorithm that comprises canny operator detection, the line of sawtooth edge is extracted; Sawtooth feature point extraction, extracts five feature points that are easy to come out by image recognition; Sawtooth parameter calculation, through five feature points, calculate the five parameters of back angle α, rake angle γ, tooth back Rb, tooth width T, and tooth depth H;

To calculate the tooth wear, subtract the three parameters of the front angle, back angle, and tooth back of the standard tooth shape from the three parameters of the front angle, back angle, and back of each tooth before grinding, and then calculate the The rake angle difference, back angle difference, and tooth back difference are respectively averaged to obtain the average wear value of the front angle Δγ, the average wear value of the back angle Δα, and the average wear value of the tooth back ΔRb, which characterize the circular saw blade in the previous cycle. In the wheel cutting operation, the three parameters of the rake angle, back angle and tooth back are worn respectively.

As a preference, the SVM model is expressed as follows:

T

w x+b=0

In the above formula, x represents the input parameters of the SVM model, w represents the normal vector of the classification hyperplane, T represents the transposition of the vector, and b represents the offset of the hyperplane relative to the origin; among them, the input parameter x is the average wear value of the rake angle Δγ , the average wear value of the rear angle Δα, and the average wear value of the tooth back ΔRb three parameters;

Assuming that the output parameter of the SVM model is y, the value of the output parameter y has only two states, and y=+1 indicates that the selection of the sawtooth parameter is appropriate, and y=-1 indicates that the selection of the sawtooth parameter is inappropriate;

Each circular saw blade can obtain a data (x, y), and use multiple circular saw blades of the same type to obtain a sample set for training the SVM model. The sample set is expressed as {(x ₁ , y ₁ ),(x ₂ ,y ₂ ),…,(xi _, y _i )}, where: x _i ∈ ^{R d} , y _i ∈ {+1,-1} is the category label, i=1,2, ...,n;

After the SVM model is matured through the above sample set, the SVM model can be used to judge whether the selection of sawtooth parameters is appropriate, that is, the average wear value of the front angle Δγ, the average wear value of the back angle Δα, and the average wear value of the tooth back ΔRb. Input it to the SVM model, and then get whether the sawtooth parameters of the circular saw blade match the field conditions, that is, whether the selection of the sawtooth parameters is appropriate.

As a preference, sawtooth parameters are optimized. If the above SVM model determines that the selection of sawtooth parameters is inappropriate, then adjust the parameters of the sawtooth profile to be ground. The specific adjustment principles are: first adjust the front angle, back angle, tooth Back the three parameters, then subtract the adjusted standard tooth profile parameters from the pre-grinding tooth profile parameters, and finally judge whether the adjusted front angle average wear value, back angle average wear value, and tooth back average wear value are equal, if If they are equal, the adjustment ends, otherwise repeat the above steps;

Sawtooth grinding accuracy verification, subtract the actual rake angle, back angle, and tooth back of the sawtooth after grinding from the three parameter values of the standard tooth shape, rake angle, back angle, and tooth back, to verify Whether the grinding of the saw teeth by the automatic gear grinding machine is fine; set a threshold, if the error of a certain parameter of any saw tooth on any circular saw blade exceeds 2%, the operator is required to intervene to further review the saw blade;

The evaluation of the flatness of the saw blade adopts the two parameters of tooth width T and tooth depth H, and according to the deviation value of the tooth width T and tooth depth H of all the saw teeth on the circular saw blade, it is judged whether the flatness of the circular saw blade is qualified, and the judgment threshold is It is determined by the three parameters of the diameter of the circular saw blade, the number of teeth, and the allowable range of the flatness error. The deviation value of the tooth width T of all saw teeth is within ±1%, and the deviation value of the tooth depth H of all saw teeth is within ±2.4%. Otherwise, the operator should be required to intervene to further review the saw blade.

The beneficial effects of the present invention are:

(1) High working reliability: Through the triple draining structure design of outer draining, inner blowing, and central pumping, it is ensured that the coolant in the area to be tested can be completely removed, thereby ensuring the detection accuracy;

(2) No damage to the saw blade: Since the process of draining and blowing liquid is completed by gas, and the process of pumping liquid is sucked by vacuum, and there is no part in the whole process that interferes with the saw blade, so it will not cause damage such as scratches to the surface of the saw blade;

(3) Good popularization: the present invention has simple structure and low cost, and the required air source, vacuum pump, etc. are also standing equipment in saw blade manufacturers, so the present invention has good generalization;

(4) There are many detectable parameters: through the device of the present invention and the use method of the device of the present invention, the detection of sawtooth wear, the optimization of the sawtooth profile, and the flatness detection of the saw blade can be completed automatically, and the above-mentioned processes are circular saw blade grinding. The grinding process of the circular saw blade is completed online without interrupting the tooth grinding process of the circular saw blade;

(5) The device proposed by the present invention can be used as an important part of the automatic gear grinding machine, laying a foundation for the automatic gear grinding machine to increase the closed-loop feedback control, and can improve the grinding accuracy of the automatic gear grinding machine to the saw teeth; the device proposed by the present invention The use method can greatly enhance the intelligence of the circular saw blade automatic gear grinding machine.

Description of drawings

Fig. 1 is a partial sectional structure schematic diagram one of the present invention;

Fig. 2 is a partial cross-sectional structural schematic diagram II of the present invention;

Fig. 3 is a sectional view of the present invention;

Fig. 4 is a working principle diagram of the present invention;

Fig. 5 is a schematic structural view of the bottom of the vacuum extraction tube of the present invention;

Fig. 6 is a schematic diagram of the calculation method of the sawtooth parameter scale of the present invention;

Fig. 7 is a schematic diagram of the arrangement structure of the present invention in actual use;

Fig. 8 is a flow chart of the use method of the device of the present invention;

Fig. 9 is a schematic diagram of a sawtooth parameter calculation method based on image recognition in the present invention;

Illustration: 1. High-pressure air cavity, 1a, air intake hole of high-pressure air cavity, 2. Circumferential air curtain block, 2a, cylindrical through hole, 2b, annular through hole, 3. bead hole of fill light, 4 , camera fixing through hole, 5, vacuum extraction tube, 5a, extraction port, 5b, first step line, 5c, second step line, 6, high pressure air blowing tube, 6a, metal outer tube, 7, connecting rod, 8, Return spring, 9, positioning coil, 10, overall assembly of the device of the present invention, 11, circular saw blade, 12, grinding wheel.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

Referring to Figures 1-3, a sawtooth camera device applied to a circular saw blade automatic gear grinding machine, the sawtooth camera device includes a high-pressure air cavity body 1, a circumferential air curtain block 2, a fill light bead hole 3, a camera fixed through Hole 4, vacuum extraction pipe 5, high-pressure blowing pipe 6, connecting rod 7, return spring 8 and positioning coil 9.

Both the high-pressure air cavity body 1 and the circumferential air curtain block 2 are cylindrical, and a cylindrical camera fixing through hole 4 is provided in the center of both; at the same time, the diameter of the bottom surface of the high-pressure air cavity body 1 is the same as that of the circumferential air curtain block 2 , and both are installed coaxially. An annular cavity surrounding the fixed through hole 4 of the camera is provided in the center of the high-pressure air chamber 1, and an air inlet (high-pressure air chamber air inlet) 1a is respectively provided on the two side walls of the high-pressure air chamber; 2 The upper part is provided with several cylindrical through holes 2a distributed around the periphery of the camera fixing through hole 4, and the cylindrical through holes communicate with the annular cavity of the high-pressure gas chamber; the lower part of the circumferential air curtain block 2 is provided with a ring Through hole 2b, the cross section of the annular through hole is inclined, so that the gas is sprayed obliquely outward; on the bottom surface of the circumferential air curtain block 2, there are several supplementary light bead holes 3 evenly distributed around the outer circumference of the fixed through hole 4 of the camera, A camera fill light can be installed for easy shooting of clear images.

In the present invention, the vacuum extraction pipe 5 and the high-pressure blowing pipe 6 all run through the high-pressure air cavity 1 and the circumferential air curtain block 2, and are respectively installed on both sides of the camera fixing through hole 4 on the same straight line. At the same time, the bottom of the high-pressure blowing pipe 6 is high 0.5 mm to 1 mm at the bottom of the vacuum extraction tube 5; the connecting rod 7 is fixed above the high-pressure gas cavity 1, and the fixing holes on both sides of the vacuum extraction tube 5 and the high-pressure blowing tube 6 are respectively fixed by interference fit; the return spring 8 is installed In the upper cavity wall of the high-pressure gas cavity 1, and coaxially installed with the vacuum extraction tube 5; 6 is made of non-metallic material, and the high-pressure blowing pipe 6 corresponding to the positioning coil 9 is covered with a layer of metal outer tube 6a, and the height of the metal outer tube 6a is equal to that of the positioning coil 9; Tube 6a is flat.

The device of the present invention is driven by a motor, and the motor is controlled by a controller.

When the device of the present invention is in operation, the bottom of the vacuum extraction tube should be as close as possible to the circular saw blade, but it should not interfere with the circular saw blade, because the circular saw blade needs to continue to rotate during sawtooth grinding. If the bottom of the vacuum extraction tube touches the circular saw blade, it will Scratches the surface of the saw blade. The present invention solves the problem of how to locate between the device of the present invention and the circular saw blade through the design of the connecting rod, return spring, and positioning coil. The specific process is as follows:

First, the device of the present invention continues to approach the circular saw blade. When the bottom of the vacuum extraction tube 5 touches the circular saw blade, the vacuum extraction tube 5 will be pushed up, and the return spring 8 will be compressed at this time, and the high-pressure air blowing tube 6 will The connecting rod 7 is fixed to the vacuum extraction pipe 5, so the high-pressure air blowing pipe 6 will also be pushed up synchronously, preventing the bottom of the high-pressure air blowing pipe from colliding with and damaging the surface of the circular saw blade.

Secondly, the metal outer tube 6a outside the high-pressure blowing tube 6 is also pushed up at this time, and there is a misalignment with the positioning coil 9, so that the self-inductance value of the positioning coil 9 changes. The detection circuit (such as an AC bridge) can detect the change of the self-inductance value of the positioning coil, and after the controller reads the signal value of the detection circuit, it immediately stops driving the motor, that is, stops the device of the present invention from further approaching the circular saw blade.

Finally, the controller drives the motor to rotate in reverse, that is, drives the device of the present invention to move away from the circular saw blade. At the same time, the controller detects the self-inductance value of the positioning coil synchronously. When the self-inductance value returns to the original value, the drive motor is stopped immediately. . So far, the positioning between the device of the present invention and the circular saw blade is completed, and the bottom of the vacuum extraction tube is close to the circular saw blade, but does not interfere with the circular saw blade.

As shown in Figure 4, the present invention completely excludes the cooling liquid of the automatic gear grinding machine from the field of view of the camera through the design of the triple liquid drainage structure. The detailed design ideas and working methods are shown in the figure below:

First, the outer annular air curtain drains the coolant. High-pressure gas (high-pressure gas) 1 enters the annular cavity from the air inlet of the high-pressure gas chamber body, and then enters the annular through-hole through the cylindrical through hole in the circumferential air curtain block, finally forming a circumferential annular air curtain with oblique Spray downwards and outwards to prevent the coolant of the automatic gear grinding machine from entering the field of view of the camera.

Secondly, the high-pressure air blowing pipe blows air directionally. The annular air curtain is not enough to exclude all the coolant, especially the coolant droplets bonded to the surface of the circular saw blade will pass through the annular air curtain as the circular saw blade rotates. At this time, use a high-pressure blowing pipe to blow air in the opposite direction along the forward direction of the circular saw blade to blow out the coolant droplets brought in by the circular saw blade. The direction of the gas blown out by the high-pressure blowing pipe is consistent with the direction of the annular air curtain gas to form a resultant force, and it is opposite to the forward direction of the circular saw blade to achieve the best removal effect.

Finally, a vacuum extraction tube extracts the droplets. After the directional blowing of the high-pressure blowing pipe, there are basically no coolant droplets. But just in case, for example, a little liquid drop leaks from the fixed through hole of the camera, the present invention is provided with vacuum extraction tube. The suction direction of the vacuum suction tube is consistent with the movement direction of the circular saw blade to obtain the best liquid suction effect.

The present invention adopts the triple liquid discharge structure design of external liquid discharge, internal liquid blowing, and central liquid pumping to ensure that the cooling liquid in the area to be detected can be completely removed, thereby ensuring the detection accuracy of the camera for sawtooth; at the same time, the liquid discharge, During the process of liquid blowing and pumping, there is no part in the whole process that interferes with the saw blade, so it will not cause damage such as scratches to the surface of the saw blade; the device proposed by the invention can be used as an important part of the automatic gear grinding machine. The addition of closed-loop feedback control lays the foundation for improving the grinding accuracy of automatic gear grinding machines for saw teeth.

Referring to Fig. 5, the bottom of the vacuum extraction tube of the present invention is provided with an extraction opening 5a, the extraction opening 5a has a stepped shape, and the extraction opening includes a first step line 5b and a second step line 5c. The widths of the first step line and the second step line shown in FIG. 5 are equal, and the value range can be between 1 mm and 3 mm, so as to adapt to most sawtooth sizes. In the present invention, the setting of the first step line and the second step line is to provide a scale for the image processing process, so as to facilitate the image processing to calculate the sawtooth parameters and the saw blade distance more accurately. The specific principle is shown in FIG. 6 .

The left half of Fig. 6 is the picture taken by the camera in the device of the present invention, because the second step line at the bottom of the vacuum extraction tube is closer to the camera than the first step line, so in the field of view of the camera, the second step line width value is greater than the first step line A step line width value. Since the actual first step line width value, the second step line width value, the height difference between the first step and the second step line, and the difference between the first step line and the circular saw blade are known, as shown in the figure As shown in the right half of 6, the height value between the camera and the second step line (shown by the dotted line in the right half of Figure 6) can be obtained according to the geometric relationship, so that the distance between the camera and the circular saw blade can also be obtained Get it. Furthermore, according to the actual width value of the first step line, the width value of the first step line in the viewing area, and the value of the zigzag shape in the viewing area, the actual value of the zigzag shape can be obtained through conversion.

Referring to Fig. 7, when the device of the present invention is in use, two devices can be used together. After the positioning between the device 10 of the present invention and the circular saw blade 11 is completed, a device 10 of the present invention is set before the grinding wheel 12, and a device 10 of the present invention is set after the grinding wheel. A device 10 of the present invention, wherein one device is in front of the grinding wheel to capture the sawtooth parameters before grinding, and the other device is behind the grinding wheel to capture the sawtooth parameters after grinding.

Referring to Figure 8, the above method of using the sawtooth camera device applied to the circular saw blade automatic grinding machine, install two sets of sawtooth camera devices on both sides of the grinding wheel respectively, and work according to the following process: sawtooth photography and parameter calculation, sawtooth wear Calculation, selection and evaluation of sawtooth parameters, optimization of sawtooth parameters, verification of sawtooth grinding accuracy, and evaluation of saw blade flatness; in order to complete a comprehensive evaluation of circular saw blades and sawtooth.

The sawtooth photographing and parameter calculation steps include photographing and tooth shape parameter calculation of the sawtooth before and after grinding. Fig. 9 is a calculation method of sawtooth parameters based on image recognition in the present invention, the specific process includes three steps of sawtooth edge recognition, sawtooth feature point extraction, and sawtooth parameter calculation. The sawtooth edge recognition step is shown in FIG. 9a , and algorithms such as canny operator detection can be used to extract the most edge line of the sawtooth. Sawtooth Feature Point Extraction As shown in Figure 9b, five feature points such as ABCDE in the figure are extracted. Among the above feature points, point A is the same as point B, not only the point where two straight lines intersect, but also the highest point; point E is the lowest point; point C and point D are the points where two lines intersect, and the arc curvature exists mutation; therefore, the above five points are all easily identifiable from the image. In the sawtooth parameter calculation step, the five parameters of back angle α, rake angle γ, tooth back Rb, tooth width T, and tooth depth H are calculated through five ABCDE feature points.

The sawtooth wear calculation is to subtract the standard tooth shape from the tooth shape before grinding to calculate the wear value of the three parameters of the front angle, rear angle and tooth back of the saw tooth before grinding; specifically, it refers to the standard The three parameters of the front angle, rear angle and tooth back of the tooth shape (the initial parameter value is input by the operator on the touch screen of the gear grinding machine), respectively subtract the three items of the front angle, back angle and tooth back of each tooth before grinding parameters, and then average the front angle difference, rear angle difference, and tooth back difference of all the sawtooth, and obtain the average front angle wear value Δγ, back angle average wear value Δα, and tooth back average wear value ΔRb, It characterizes how much the three parameters of the circular saw blade, the rake angle, the back angle, and the back of the tooth, are worn in the last round of cutting operation.

The evaluation of sawtooth parameter selection refers to the use of the support vector machine SVM model, using the three parameters of the average front angle wear value Δγ, the rear angle average wear value Δα, and the tooth back average wear value ΔRb as input parameters of the SVM model. Proper selection of sawtooth parameters and inappropriate selection of sawtooth parameters are used as the output parameters of the SVM model (that is, the SVM model is used for binary classification), so as to judge whether the sawtooth parameters are suitable for the working conditions of the saw blade.

The mathematical principle of the SVM model of the present invention is as follows:

The essence of the SVM model is to seek a hyperplane in a multidimensional space, which can separate data (especially separate nonlinear data) with the largest interval, so as to realize data classification. The equation of the hyperplane can be written as follows:

w ^T x + b = 0 (1)

In the above formula, x represents the input parameters of the SVM model, w represents the normal vector of the classification hyperplane, T represents the transposition of the vector, and b represents the offset of the hyperplane relative to the origin. Among them, the input parameter x is the average wear value of the front angle Δγ, the average wear value of the rear angle Δα, and the average wear value of the tooth back ΔRb. Assuming that the output parameter of the SVM model is y, in the present invention, the value of the output parameter y has only two states, y=+1 can be used to indicate that the sawtooth parameter is properly selected, and y=-1 can be used to indicate that the sawtooth parameter is not properly selected.

Each circular saw blade can obtain a data (x, y), so using a large number of circular saw blades of the same type can obtain a sample set for training the SVM model. The sample set can be expressed as {(x ₁ ,y ₁ ),(x ₂ ,y ₂ ),…,(xi _, y _i )}, where: x _i ∈ ^{R d} , y _i ∈ {+1,-1} is the category label, i=1 ,2,...,n.

After the SVM model is matured through the above sample set, the SVM model can be used to judge whether the selection of sawtooth parameters is appropriate, that is, the average wear value of the front angle Δγ, the average wear value of the back angle Δα, and the average wear value of the tooth back ΔRb. Input to the SVM model, and then the SVM model can tell the operator whether the saw tooth parameters of the circular saw blade match the on-site working conditions, that is, whether the selection of the saw tooth parameters is appropriate.

The sawtooth parameter optimization refers to adjusting the parameters of the sawtooth shape to be ground, especially the three parameters of the rake angle, back angle and tooth back, if the aforementioned SVM model determines that the selection of the sawtooth parameters is inappropriate. The specific adjustment principle is as follows: first adjust the three parameters of the standard tooth profile, the front angle, the back angle, and the back of the tooth, and then subtract the adjusted standard tooth profile parameters from the pre-grinding tooth profile parameters, and finally determine the average of the adjusted front angle Whether the wear value, the average wear value of the rear angle, and the average wear value of the tooth back are equal, and if they are equal, the adjustment is ended, otherwise, repeat the above steps.

The calibration of sawtooth grinding accuracy refers to the subtraction calculation between the standard tooth shape and the ground tooth shape to calculate the grinding error of the sawtooth tooth shape parameters. Specifically, the actual rake angle, rear angle, and tooth back of the saw tooth after grinding are subtracted from the three parameter values of the standard tooth shape, rake angle, back angle, and tooth back, to verify the automatic grinding Whether the grinding of the saw teeth by the gear machine is accurate. A threshold can be set, and if the error of a certain parameter of any tooth on any circular saw blade exceeds 2%, the operator is required to intervene to further examine the saw blade.

The evaluation of the flatness of the saw blade refers to calculating the flatness of different teeth on the same saw blade after grinding according to the two parameters of tooth width and tooth depth after grinding. The specific basis for evaluating the flatness of the saw blade is: when When the flatness of the circular saw blade is good, each sawtooth should be the same size in the field of view of the camera; when the circular saw blade is warped, the sawtooth that is upturned (closer to the camera) will be larger in the field of view of the camera, and concave downward The aliasing (far from the camera) will be smaller in the camera's field of view. In actual operation, the present invention uses the two parameters of tooth width T and tooth depth H in Fig. 8 to determine whether the flatness of the circular saw blade is Qualified, the judgment threshold is determined by three parameters: the diameter of the circular saw blade, the number of teeth, and the allowable range of flatness error. For example, a circular saw with a diameter of 300 mm, a number of saw teeth of 100 teeth, and a flatness error of ±10 If the tooth width T is 9.42 mm and the tooth depth H is 4.24 mm, the deviation of the tooth width T of all the saw teeth should be within ±1% (that is, the maximum and minimum saw tooth widths captured in the field of view of the camera) , wider than the average tooth width, the deviation should be controlled within 1%), and the deviation value of the tooth depth H of all saw teeth should be within ±2.4%, otherwise the operator should be required to intervene to further review the saw blade.

The sawtooth camera device applied to the automatic gear grinding machine proposed by the present invention has the characteristics of high reliability of liquid drainage, no damage to the saw blade, simple and stable structure, and good popularization. The use method of the sawtooth camera device proposed by the present invention has the advantages of Fully automatic on-line detection of sawtooth wear, sawtooth profile optimization, and saw blade flatness detection. Therefore, installing the device of the present invention on the automatic gear grinding machine and using the method of the present invention can greatly enhance the grinding accuracy and intelligence of the automatic gear grinding machine.

The above specific embodiments are used to explain the present invention, rather than to limit the present invention. Within the spirit of the present invention and the protection scope of the claims, any modification and change made to the present invention will fall into the protection scope of the present invention.

Claims (10)

1. A sawtooth camera device applied to an automatic gear grinding machine for circular saw blades, characterized in that: the sawtooth camera device includes a high-pressure air cavity, a circumferential air curtain block, a fill light bead hole, a camera fixing through hole, a vacuum Extraction pipe, high-pressure blowing pipe, connecting rod, return spring and positioning coil, the high-pressure air cavity communicates with the circumferential air curtain block, and the camera fixing through hole is arranged at the center of the high-pressure air cavity and the circumferential air curtain block , the bead hole of the supplementary light is located at the bottom of the circumferential air curtain block; the vacuum extraction pipe and the high-pressure air blowing pipe run through the high-pressure air cavity and the circumferential air curtain block, and are respectively installed on both sides of the camera fixing through hole; the connection The rod is set above the high-pressure gas cavity, and the two ends of the connecting rod are respectively fixed with the fixed vacuum extraction tube and the high-pressure blowing tube through interference fit; the return spring is installed in the upper wall of the high-pressure gas cavity, and is connected with the vacuum extraction tube Coaxial installation; the positioning coil is installed in the upper cavity wall of the high-pressure gas chamber, and is installed coaxially with the high-pressure blowing pipe; An annular cavity surrounding the fixed through hole of the camera is set in the center of the high-pressure air cavity, and an air intake hole is respectively set on the two side walls of the high-pressure gas cavity; There are several cylindrical through-holes distributed around the periphery of the hole, and the cylindrical through-holes communicate with the annular cavity of the high-pressure gas chamber; an annular through-hole is opened in the lower half of the circumferential air curtain block, and the cross-section of the annular through-hole is an inclined structure. 2. According to claim 1, the sawtooth camera device applied to the automatic gear grinding machine for circular saw blades is characterized in that: the high-pressure air cavity and the circumferential air curtain block are two cylinders with the same bottom diameter, and both are the same shaft mount. 3. According to claim 1, the sawtooth camera device applied to the automatic gear grinding machine for circular saw blades is characterized in that: the bead hole of the supplementary light is set on the bottom surface of the circumferential air curtain block, and surrounds the outside of the circumference of the fixed through hole of the camera Evenly distributed. 4. The sawtooth camera device applied to the circular saw blade automatic grinding machine according to claim 1, wherein the bottom of the high-pressure air blowing pipe is 0.5 mm to 1 mm higher than the bottom of the vacuum suction pipe. 5. According to claim 1, the sawtooth camera device applied to automatic gear grinding machines for circular saw blades is characterized in that: a layer of metal outer tube is placed outside the high-pressure blowing tube corresponding to the positioning coil, and the height of the metal outer tube is the same as Positioning coils are equal. 6. According to claim 1, the sawtooth camera device applied to the automatic gear grinding machine for circular saw blades is characterized in that: the bottom of the vacuum extraction pipe is provided with an extraction port, the shape of the extraction port is stepped, and the extraction port includes a second The first step line and the second step line, the width of the first step line and the second step line are equal; the width of the first step line and the second step line is 1 mm to 3 mm. 7. A method for using the sawtooth camera device applied to the circular saw blade automatic gear grinding machine according to claim 1, characterized in that: two sets of sawtooth camera devices are respectively installed on both sides of the grinding wheel, and work according to the following process: Sawtooth shooting and parameter calculation, sawtooth wear calculation, sawtooth parameter selection evaluation, sawtooth parameter optimization, sawtooth grinding accuracy verification, saw blade flatness evaluation; Sawtooth shooting and parameter calculation: including shooting and tooth shape parameter calculation of the sawtooth before and after grinding, the tooth shape parameter calculation process includes sawtooth edge recognition, sawtooth feature point extraction, and sawtooth parameter calculation; Sawtooth wear calculation: Subtract the standard tooth shape from the tooth shape before grinding to calculate the wear value of the three parameters of the front angle, rear angle and tooth back of the saw tooth before grinding; Sawtooth parameter selection evaluation: use the support vector machine SVM model, take the three parameters of front angle average wear value, rear angle average wear value, and tooth back average wear value as the input parameters of the SVM model, and properly select the sawtooth parameter, sawtooth parameter Inappropriate selection as the output parameter of the SVM model, in order to judge whether the sawtooth parameters are suitable for the working conditions of the saw blade; Sawtooth parameter optimization: adjust the average wear value of the front angle, the average wear value of the rear angle, and the average wear value of the tooth back of the tooth shape parameters to be ground; Sawtooth grinding accuracy verification: subtract the standard tooth shape from the tooth shape after grinding to calculate the grinding error of the tooth shape parameters; Saw blade flatness evaluation: According to the two parameters of tooth width and tooth depth after grinding, calculate the flatness of different teeth on the same saw blade after grinding, and then judge whether the saw blade after grinding is qualified. 8. The method for using the sawtooth camera device applied to the circular saw blade automatic grinding machine according to claim 7, characterized in that: for sawtooth edge recognition, an algorithm including canny operator detection is used to convert the line at the edge of the sawtooth Extraction; sawtooth feature point extraction, extracting five feature points that are easy to recognize through images; sawtooth parameter calculation, through five feature points, calculate back angle α, front angle γ, tooth back Rb, tooth width T, tooth depth H Five parameters; To calculate the tooth wear, subtract the three parameters of the front angle, back angle, and tooth back of the standard tooth shape from the three parameters of the front angle, back angle, and back of each tooth before grinding, and then calculate the The rake angle difference, back angle difference, and tooth back difference are respectively averaged to obtain the average wear value of the front angle Δγ, the average wear value of the back angle Δα, and the average wear value of the tooth back ΔRb, which characterize the circular saw blade in the previous cycle. In the wheel cutting operation, the three parameters of the rake angle, back angle and tooth back are worn respectively. 9. The method for using the sawtooth camera device applied to the circular saw blade automatic gear grinding machine according to claim 8, wherein the SVM model is expressed as follows: T w x+b=0 In the above formula, x represents the input parameters of the SVM model, w represents the normal vector of the classification hyperplane, T represents the transposition of the vector, and b represents the offset of the hyperplane relative to the origin; among them, the input parameter x is the average wear value of the rake angle Δγ , the average wear value of the rear angle Δα, and the average wear value of the tooth back ΔRb three parameters; Assuming that the output parameter of the SVM model is y, the value of the output parameter y has only two states, and y=+1 indicates that the selection of the sawtooth parameter is appropriate, and y=-1 indicates that the selection of the sawtooth parameter is inappropriate; Each circular saw blade can obtain a data (x, y), and use multiple circular saw blades of the same type to obtain a sample set for training the SVM model. The sample set is expressed as {(x ₁ , y ₁ ),(x ₂ ,y ₂ ),…,(x _i ,y _i )}, where: x _i ∈ ^{R d} , y _i ∈ {+1,-1} is the category label, i=1,2,…,n; After the SVM model is matured through the above sample set, the SVM model can be used to judge whether the selection of sawtooth parameters is appropriate, that is, the average wear value of the front angle Δγ, the average wear value of the back angle Δα, and the average wear value of the tooth back ΔRb. Input it to the SVM model, and then get whether the sawtooth parameters of the circular saw blade match the field conditions, that is, whether the selection of the sawtooth parameters is appropriate. 10. According to claim 9, the method for using the sawtooth camera device applied to the circular saw blade automatic grinding machine is characterized in that: sawtooth parameter optimization, if the SVM model determines that the sawtooth parameter selection is inappropriate, then adjust the The specific adjustment principle for grinding sawtooth profile parameters is as follows: first adjust the three parameters of the standard tooth profile, the rake angle, rear angle, and tooth back, and then subtract the adjusted standard tooth profile parameters from the pre-grinding tooth profile parameters. Finally, judge whether the adjusted average wear value of the front angle, the average wear value of the back angle, and the average wear value of the tooth back are equal. If they are equal, the adjustment is ended, otherwise, repeat the above steps; Sawtooth grinding accuracy verification, subtract the actual rake angle, back angle, and tooth back of the sawtooth after grinding from the three parameter values of the standard tooth shape, rake angle, back angle, and tooth back, to verify Whether the grinding of the saw teeth by the automatic gear grinding machine is fine; set a threshold, if the error of a certain parameter of any saw tooth on any circular saw blade exceeds 2%, the operator is required to intervene to further review the saw blade; The evaluation of the flatness of the saw blade adopts the two parameters of tooth width T and tooth depth H, and according to the deviation value of the tooth width T and tooth depth H of all the saw teeth on the circular saw blade, it is judged whether the flatness of the circular saw blade is qualified, and the judgment threshold is It is determined by the three parameters of the diameter of the circular saw blade, the number of teeth, and the allowable range of the flatness error. The deviation value of the tooth width T of all saw teeth is within ±1%, and the deviation value of the tooth depth H of all saw teeth is within ±2.4%. Otherwise, the operator should be required to intervene to further review the saw blade.

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