Portable gear measuring device and measuring method based on line laser displacement sensor

Abstract

The invention discloses a portable gear measuring device and a measuring method based on a line laser displacement sensor. The device comprises a base, on which is connected a line laser displacement sensor which can be adjusted in left-right, front-back and height directions. Clamping plates are rotatably connected to the base on both sides of the line laser displacement sensor facing outwards. Clamping claws are fixedly connected to one side of two clamping plates which are arranged opposite to each other, and an electromagnet is connected to the base between the two clamping claws. The device can realize non-contact measurement of large gears, and the measurement is convenient.

Description

Technical Field

[0001] The invention relates to the technical field of gear measurement, in particular to a portable gear measuring device and a measuring method based on a line laser displacement sensor. Background Art

[0002] Large gears are key components for manufacturing large equipment and play an irreplaceable role in the military, aerospace and other fields. Therefore, the measurement accuracy requirements for large gears are getting higher and higher. Large gears are usually tested using CNC gear measuring centers and three-dimensional coordinate measuring machines. However, due to the high production costs and the large size of large gears, many experts in the industry have begun to study the method of online measurement, that is, there is no need to move the gears, but to install the gear measuring instrument on the gear to be measured or the gear processing machine tool in the form of in-situ measurement. The measurement is troublesome, which requires the development of a portable device for measuring gears. Summary of the invention

[0003] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0004] In view of the above problems and / or problems existing in the power transmission of the prior art, the present invention is proposed.

[0005] Therefore, in order to solve the technical problem of low transmission power in the prior art, the present invention provides a portable gear measuring device and a measuring method based on a line laser displacement sensor, which can realize gear measurement in a portable manner and facilitate the removal and replacement of gears.

[0006] In order to solve the above technical problems, the present invention provides the following technical solutions: a portable gear measuring device based on a line laser displacement sensor, which includes a base, to which is connected a line laser displacement sensor whose position can be adjusted in left and right, front and back directions, and height directions; clamping plates are rotatably connected to the base on both sides of the line laser displacement sensor facing outward, and clamping claws are fixedly connected to one side of the two clamping plates that are arranged opposite to each other, and an electromagnet is connected to the base between the two clamping claws.

[0007] As a further improvement of the present invention, the base is connected to a sliding seat that can slide left and right, the sliding seat is connected to a fixed bracket that can slide forward and backward, the upper end of the fixed bracket is connected to a height-adjustable clamp, the lower part of the fixed bracket is connected to a height-adjustable support block, the linear laser displacement sensor is connected to the upper side of the support block, and the clamp presses the linear displacement sensor onto the support block.

[0008] In order to further realize the position adjustment of the line laser displacement sensor in the left and right and front and back directions, a fixed seat is fixedly connected to the base between the two clamping plates, a lower slider is slidably connected to the fixed seat, a first adjusting screw is rotatably connected to the fixed seat under the base, the lower slider is threadedly connected to the first adjusting screw, the sliding seat is fixedly connected to the lower slider, an upper slider is slidably connected to the sliding seat, a second adjusting screw is threadedly connected to the sliding seat, the upper slider is threadedly connected to the second adjusting screw, a fixed platform is provided above the sliding seat, the fixed platform and the upper slider are fixedly connected, and the fixed bracket is fixedly connected to the fixed platform.

[0009] In order to further realize the clamping of the gear to be tested, the lower side of the base is fixedly connected to a bearing seat, and both ends of the bearing seat are rotatably connected to a first angle adjustment screw and a second angle adjustment screw, and the rotation directions of the first angle adjustment screw and the second angle adjustment screw are opposite. The base is provided with a first slide groove and a second slide groove, and the first angle adjustment screw is threadedly connected to a first angle adjustment slider, and the first angle adjustment slider can just slide along the first slide groove, and the second angle adjustment slider is threadedly connected to the second angle adjustment slider, and the second angle adjustment slider can just slide along the second slide groove, and an angle adjustment slide groove is provided on the clamping plate, and the upper end of the first angle adjustment slider is slidably connected to a corresponding clamping plate via a corresponding angle adjustment slide groove, and the upper end of the second angle adjustment slider is slidably connected to the other clamping plate via another angle adjustment slide groove.

[0010] In order to further realize the adjustment of the position of the line laser displacement sensor in the height direction, a fixed plate is fixed to the lower part of the fixed bracket, and a vertically arranged height adjustment screw is rotatably connected to the fixed plate. The support block is threadedly connected to the height adjustment screw, and a reset elastic member is connected to the upper end of the fixed bracket. At least one guide rod is arranged on the lower side of the clamping plate, and the guide rod is slidably connected to the fixed bracket. The upper end of the reset elastic member is connected to the clamping plate. When the line laser displacement sensor is between the support block and the clamping plate, the reset elastic member is in a stretched state.

[0011] A method for measuring a gear using a measuring device, comprising the following steps:

[0012] The first angle adjustment screw and the second angle adjustment screw are rotated to open the two clamping jaws until the gear to be measured can be just installed, the first angle adjustment screw and the second angle adjustment screw are stopped, the gear to be measured is placed between the two clamping jaws, and the first angle adjustment screw and the second angle adjustment screw are continued to be rotated to make the clamping jaws just clamp the tooth profile of the gear to be measured, the electromagnet is energized, and the gear to be measured is further adsorbed on the base;

[0013] Rotate the second adjusting screw to adjust the position of the linear laser displacement sensor in the front-rear direction so that the gear to be measured is within the measuring range of the linear laser displacement sensor, and stop rotating the second adjusting screw;

[0014] Rotate the first adjusting screw to center the incident laser of the line laser displacement sensor, stop rotating the first adjusting screw, and rotate the height adjusting screw to achieve measurement of different tooth profile sections on the gear to be measured;

[0015] The line laser displacement sensor receives the reflected laser from the tooth profile surface and converts it into relative displacement data and coordinate data of each point on the tooth profile. The converted data is imported into the computer terminal, the corresponding tooth profile curve is drawn, and multiple deviations of the gear are calculated and analyzed.

[0016] In order to further realize the calculation of the three-dimensional coordinates of each point on the tooth profile, the relative displacement and coordinate data conversion steps of each point on the tooth profile are as follows: set any point on the gear involute as H(x H ,y H ), O(x0,y0) is the center of the tooth root circle, r O is the tooth root radius, α H is the pressure angle at point H on the tooth profile, H1 is the starting point of laser measurement, θ is the angle from laser point H to the starting laser point during measurement, l1 is the normal at point H on the involute, the distance from H1 to the center of the gear is d1, d1=y1+r0, connect H1O, and intersect with the root circle at point h1, y1 is the distance from point H1 to h1, r0 is the radius of the root circle, and its coordinates can be expressed as H1(0,d1,z1), z1 is the vertical distance from laser point H1 on the tooth profile surface to the lower end face of the gear, and point H is the measurement laser point of the gear with an angle of θ from the starting measurement point, connect HO, and intersect with the root circle at point h, the distance from point H to the center of the gear is d H , d H =y H +r0,y H is the distance from point H to h, and the three-dimensional coordinates of any point H on the tooth profile are H(d H sinθ,d H cosθ,z H ).

[0017] In order to further realize the total tooth profile deviation on any tooth profile section, the tooth profile deviation F at the i-th point on the actual tooth profile line i The normal distance ΔS to the theoretical tooth profile curve i , the total deviation F within the effective length of the tooth profile curve 总 , F 总 =F max -F min =MAXΔs-MINΔs; Assume that any point G(xG ,y G The intersection point of the normal line at ) and the actual tiny line segment is H′(x H′ ,y H′ ), then the tooth profile deviation at point H′ is F H’ F H′ =ΔS H′ =d GH′ , the coordinate equation of the intersection point H′ on the tiny line segment is,

[0018]

[0019] k is the point G(x G ,y G ), and according to the involute construction equation of the gear, it can be known that any point G(x G ,y G ) can be expressed as, α G is the pressure angle at point G on the tooth profile;

[0020] The actual tooth profile curve H′(x H′ ,y H′ ) tooth profile deviation F H’ for,

[0021] Total tooth profile deviation F on any section 总 F 总 =MAX(F H′ )-MIN(F H′ ), MAX(F H’ ) is the maximum tooth profile error value obtained on the calculated tooth profile section, MIN(F H’ ) is the minimum tooth profile error value obtained on the calculated tooth profile section.

[0022] In order to further fit more coordinate points, four adjacent coordinate points H on the tooth profile section are selected in turn. i (x i ,y i ),H i+1 (x i+1 ,y i+1 ),H i+2 (x i+2 ,y i+2 ),H i+3 (x i+3 ,y i+3 ), and interpolation processing is performed based on the differential evolution algorithm, and the interpolation expression of the tooth profile coordinate point is deduced as follows:

[0023]

[0024] in,

[0025] In the above formula,

[0026] l is the interpolation point (x, F (x) ) to point H i+1 and point H i+2 Distance from midpoint, ΔS i Point H i The normal distance to the theoretical tooth profile line is |l-ΔS i |≤10 -3 mm is the interpolation search range condition for iterative calculation, and the interpolation refinement of the tooth profile points can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them:

[0028] Figure 1 The three-dimensional structure of the measuring device in the present invention Figure 1 .

[0029] Figure 2 for Figure 1 A partial enlarged view of point A in the middle.

[0030] Figure 3 The three-dimensional structure of the measuring device in the present invention Figure 2 .

[0031] Figure 4 The three-dimensional structure of the measuring device in the present invention Figure 3 .

[0032] Figure 5 for Figure 4 A partial enlarged view of point B in the middle.

[0033] Figure 6 The three-dimensional structure of the measuring device in the present invention Figure 4 .

[0034] Figure 7 The three-dimensional structure of the measuring device in the present invention Figure 5 .

[0035] Figure 8 It is a specific schematic diagram of coordinate conversion in the present invention.

[0036] Fig. 9It is a specific schematic diagram of the deviation calculation principle and method in the present invention.

[0037] In the figure, 1 is a base, 2 is a clamping plate, 3 is a second angle adjustment slider, 301 is an angle adjustment slot, 4 is a clamping plate, 5 is a line laser displacement sensor, 6 is a sliding seat, 7 is a fixed seat, 8 is a first adjustment screw, 801 is a first adjustment handle, 9 is a lower slider, 10 is a fixed table, 11 is a first angle adjustment screw, 12 is a height adjustment screw, 1201 is a height adjustment handle, 13 is a reset elastic member, 14 is a second angle adjustment screw, 1401 is an angle adjustment handle, 15 is a first angle adjustment slider, 16 is a bearing seat, 17 is an electromagnet, 18 is a clamping claw, 19 is a guide rod, 20 is a fixed bracket, 21 is a second adjustment screw, 2101 is a second adjustment handle, 22 is an upper slider, and 23 is a support block. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the accompanying drawings.

[0039] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0040] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0041] Example 1

[0042] Reference Figure 1 to Figure 7 This embodiment provides a portable gear measuring device and a measuring method based on a line laser displacement sensor, which can realize non-contact measurement of gears.

[0043] A portable gear measuring device based on a linear laser displacement sensor 5 comprises a base 1, to which is connected a linear laser displacement sensor 5 which can be adjusted in position in left and right, front and back directions and in height directions; a sliding seat 6 which can slide left and right is connected to the base 1; a fixed bracket 20 which can slide front and back is connected to the sliding seat 6; a height-adjustable clamping plate 4 is connected to the upper end of the fixed bracket 20; a height-adjustable support block 23 is slidably connected to the lower part of the fixed bracket 20; the linear laser displacement sensor 5 is connected to the upper side of the support block 23; the clamping plate 4 presses the linear displacement sensor onto the support block 23; clamping plates 2 are rotatably connected to the base 1 on both sides of the linear laser displacement sensor 5 facing outward; a clamping claw 18 is fixedly connected to one side of the two clamping plates 2 which are arranged opposite to each other; an electromagnet 17 is connected to the base 1 between the two clamping claws 18.

[0044] In order to further realize the position adjustment of the line laser displacement sensor 5 in the left and right and front and back directions, a fixed seat 7 is fixedly connected to the base 1 between the two clamping plates 2, and a lower slider 9 is slidably connected to the fixed seat 7. A first adjusting screw 8 is rotatably connected to the fixed seat 7 below the base 1, and the lower slider 9 is threadedly connected to the first adjusting screw 8. The sliding seat 6 is fixedly connected to the lower slider 9, and an upper slider 22 is slidably connected to the sliding seat 6. A second adjusting screw 21 is threadedly connected to the sliding seat 6, and the upper slider 22 is threadedly connected to the second adjusting screw 21. A fixed platform 10 is fixedly connected above the sliding seat 6, and the fixed platform 10 and the upper slider 22 are fixedly connected, and a fixed bracket 20 is fixedly connected to the fixed platform 10; a first adjusting handle 801 is fixed to the outer end of the first adjusting screw 8, and a second adjusting handle 2101 is fixed to the outer end of the second adjusting screw 21.

[0045] When it is necessary to adjust the position of the line laser displacement sensor 5 in the left and right and front and back directions, turn the first adjustment handle 801, the first adjustment screw 8 drives the lower slider 9 to move in the left and right directions, and the lower slider 9 drives the line laser displacement sensor 5 to move in turn through the sliding seat 6 and the fixed bracket 20. When the position of the line laser displacement sensor 5 in the left and right directions is adjusted to the required position, stop turning the first adjustment screw 8; turn the second adjustment handle 2101, the second adjustment screw 21 drives the upper slider 22 to move in the front and back directions, and the upper slider 22 drives the line laser displacement sensor 5 to move through the fixed bracket 20. When the position of the line laser displacement sensor 5 in the front and back directions is adjusted to the required position, stop turning the second adjustment screw 21.

[0046] In order to further clamp the gear to be tested, a bearing seat 16 is fixedly connected to the lower side of the base 1, and the two ends of the bearing seat 16 are rotatably connected to the first angle adjustment screw 11 and the second angle adjustment screw 14. The outer end of the second angle adjustment screw 14 is fixed with an angle adjustment rotating handle. The first angle adjustment screw 11 and the second angle adjustment screw 14 are connected together, and the rotation directions of the first angle adjustment screw 11 and the second angle adjustment screw 14 are opposite. The base 1 is provided with a first slide groove and a second slide groove, and the first angle adjustment screw 11 is threadedly connected with The first angle adjustment slider 15 can just slide along the first slide groove, the second angle adjustment screw 14 is threadedly connected with the second angle adjustment slider 3, the second angle adjustment slider 3 can just slide along the second slide groove, and the clamping plate 2 is provided with an angle adjustment slide groove 301. The upper end of the first angle adjustment slider 15 is slidably connected to a corresponding clamping plate 2 through a corresponding angle adjustment slide groove 301, and the upper end of the second angle adjustment slider 3 is slidably connected to another clamping plate 2 through another angle adjustment slide groove 301.

[0047] When it is necessary to clamp the gear to be measured, the first angle adjustment handle 1401 and the second angle adjustment handle 1401 are rotated at the same time, the first angle adjustment screw 11 and the second angle adjustment screw 14 respectively drive the first angle adjustment slider 15 and the second angle adjustment slider 3 to move in the left and right directions, so that the first angle adjustment slider 15 and the second angle adjustment slider 3 move outward, the first angle adjustment slider 15 and the second angle adjustment slider 3 respectively drive the two clamping plates 2 to swing outward, and the two clamping plates 2 drive the corresponding clamping jaws 18 to open outward, and when the gear to be measured can be just placed between the two clamping jaws 18, the rotation of the first angle adjustment screw 11 and the second angle adjustment screw 14 is stopped; the first angle adjustment handle 1401 and the second angle adjustment handle 1401 are continued to be rotated, and when the clamping jaws 18 can just clamp the tooth profile of the gear to be measured, the rotation of the first angle adjustment handle 1401 and the second angle adjustment handle 1401 is stopped, and the electromagnet 17 is actuated, and the electromagnet 17 adsorbs and fixes the gear to be measured on the base 1.

[0048] In order to further realize the adjustment of the position of the line laser displacement sensor 5 in the height direction, a fixed plate is fixed to the lower part of the fixed bracket 20, and a vertically arranged height adjustment screw 12 is rotatably connected to the fixed plate, and a height adjustment handle 1201 is fixed to the lower end of the height adjustment screw 12, and the support block 23 is threadedly connected to the height adjustment screw 12, and the upper end of the fixed bracket 20 is connected to a reset elastic member 13, and the reset elastic member 13 is a spring. At least one guide rod 19 is arranged on the lower side of the splint 4, and the guide rod 19 is slidably connected to the fixed bracket 20, and the upper end of the reset elastic member 13 is connected to the splint 4, and the downward end of the line laser displacement sensor 5 is inserted into the plug-in portion on the upper side of the support block 23. When the line laser displacement sensor 5 is between the support block 23 and the splint 4, the reset elastic member 13 is in a stretched state.

[0049] When adjusting the position of the line laser displacement sensor 5 in the height direction, turn the height adjustment handle 1201, the height adjustment screw 12 rotates, the height adjustment screw 12 drives the support block 23 to move in the height direction, and the support block 23 drives the line laser displacement sensor 5 to move. For example, when the support block 23 moves upward, the support block 23 moves upward against the line laser displacement sensor 5, and the line laser displacement sensor 5 drives the splint 4 to move upward, the reset elastic member 13 is further stretched, and the splint 4 further presses the line laser displacement sensor 5 on the upper side of the support block 23; when the support block 23 moves downward, the splint 4 is reset downward under the action of the reset elastic member 13, and the splint 4 always contacts the upper side of the line laser displacement sensor 5.

[0050] Example 2

[0051] Reference Figure 8 and Fig. 9 , this embodiment provides a method for measuring a gear using a measuring device, which can further realize the measurement of the gear.

[0052] The method for measuring a gear using a measuring device comprises the following steps:

[0053] The first angle adjustment screw 11 and the second angle adjustment screw 14 are rotated to open the two clamping jaws 18 until the gear to be measured can be just installed, the first angle adjustment screw 11 and the second angle adjustment screw 14 are stopped from rotating, the gear to be measured is placed between the two clamping jaws 18, and the first angle adjustment screw 11 and the second angle adjustment screw 14 are continued to rotate to make the clamping jaws 18 just clamp the tooth profile of the gear to be measured, the electromagnet 17 is energized, and the gear to be measured is further adsorbed on the base 1;

[0054] Rotate the second adjusting screw 21 to adjust the position of the linear laser displacement sensor 5 in the front-rear direction so that the gear to be measured is within the measuring range of the linear laser displacement sensor 5, and stop rotating the second adjusting screw 21;

[0055] The first adjusting screw 8 is rotated to center the incident laser of the line laser displacement sensor 5, the first adjusting screw 8 is stopped, and the height adjusting screw 12 is rotated to achieve measurement of different tooth profile sections on the gear to be measured;

[0056] The line laser displacement sensor 5 receives the reflected laser from the tooth profile surface, converts it into relative displacement data and coordinate data of each point on the tooth profile, imports the converted data into a computer terminal, draws the corresponding tooth profile curve, and calculates and analyzes multiple deviations of the gear.

[0057] In order to further realize the calculation of the three-dimensional coordinates of each point on the tooth profile, the relative displacement and coordinate data conversion steps of each point on the tooth profile are as follows: set any point on the gear involute as H(x H ,y H ), O(x0,y0) is the center of the tooth root circle, r O is the tooth root radius, α H is the pressure angle at point H on the tooth profile, H1 is the starting point of laser measurement, θ is the angle from laser point H to the starting laser point during measurement, l1 is the normal at point H on the involute, the distance from H1 to the center of the gear is d1, d1=y1+r0, connect H1O, and intersect with the root circle at point h1, y1 is the distance from point H1 to h1, r0 is the radius of the root circle, and its coordinates can be expressed as H1(0,d1,z1), z1 is the vertical distance from laser point H1 on the tooth profile surface to the lower end face of the gear, and point H is the measurement laser point of the gear with an angle of θ from the starting measurement point, connect HO, and intersect with the root circle at point h, the distance from point H to the center of the gear is d H , d H =y H +r0,y H is the distance from point H to h, and the three-dimensional coordinates of any point H on the tooth profile are H(d H sinθ,d H cosθ,z H ).

[0058] In order to further realize the total tooth profile deviation on any tooth profile section, the tooth profile deviation F at the i-th point on the actual tooth profile line i The normal distance ΔS to the theoretical tooth profile curve i , the total deviation F within the effective length of the tooth profile curve 总 , F 总 =F max -F min =MAXΔs-MINΔs; Assume that any point G(x G ,y G The intersection point of the normal line at ) and the actual tiny line segment is H′(x H′ ,y H′ ), then the tooth profile deviation at point H′ is FH’ F H′ =ΔS H′ =d GH′ , the coordinate equation of the intersection point H′ on the tiny line segment is,

[0059]

[0060] k is the point G(x G ,y G ), and according to the involute construction equation of the gear, it can be known that any point G(x G ,y G ) can be expressed as, α G is the pressure angle at point G on the tooth profile;

[0061] The actual tooth profile curve H′(x H′ ,y H′ ) tooth profile deviation F H’ for,

[0062] Total tooth profile deviation F on any section 总 F 总 =MAX(F H′ )-MIN(F H′ ), MAX(F H’ ) is the maximum tooth profile error value obtained on the calculated tooth profile section, MIN(F H’ ) is the minimum tooth profile error value obtained on the calculated tooth profile section.

[0063] In order to further fit more coordinate points, four adjacent coordinate points H on the tooth profile section are selected in turn. i (x i ,y i ),H i+1 (x i+1 ,y i+1 ),H i+2 (x i+2 ,y i+2 ),H i+3 (x i+3 ,y i+3 ), and interpolation processing is performed based on the differential evolution algorithm, and the interpolation expression of the tooth profile coordinate point is deduced as follows:

[0064]

[0065] in,

[0066] In the above formula,

[0067] l is the interpolation point (x, F (x) ) to point H i+1 and point H i+2 Distance from midpoint, ΔS i Point H i The normal distance to the theoretical tooth profile line is then calculated as l-ΔS i ≤10 -3 mm is the interpolation search range condition for iterative calculation, and the interpolation refinement of the tooth profile points can be achieved.

[0068] According to the definition of 3×3 order non-uniform rational B-spline surface, it is easy to know that the general rational basis function of the overall deviation of the tooth profile can be expressed as:

[0069]

[0070] In the above formula, P i,j is the three-dimensional matrix form of the tooth profile coordinate points, S(u,v) is the non-uniform rational B-spline surface form of the measured tooth profile surface, R i,3；j,3 (u,v) is the rational basis function in the above non-uniform rational B-spline surface expression, w i,j are the three-dimensional coordinate control points P on the fitted tooth profile surface i,j The weight factor, and w i,j ≥0, m and n are the degrees of the fitted B-spline curve in the directions of parameters u and v, respectively, and parameters u, v∈[0,1].

[0071] Based on expression (2), the three-dimensional coordinate form of the tooth profile needs to be converted into the form of a three-dimensional data point matrix, namely:

[0072] P i,j ={H a,b =(x a,b ,y a,b ,z a,b )}

[0073] ={H a,b =((d H sinθ) a,b ,(d H cosθ) a,b ,(z H ) a,b )} (3);

[0074] θ is the angle from the laser point to the starting laser point during the measurement process, a and b represent the row number and column number of the data point matrix respectively, (d H sinθ) a,b ,(d H cosθ) a,b and (Z H )a,b are the x-coordinate value, y-coordinate value and z-coordinate value of the tooth profile coordinate point in the ath row and bth column respectively. The tooth profile coordinate points refined by interpolation of formula (1) are converted into matrix form according to formula (3) above, and then brought into the 3×3 order non-uniform rational B-spline surface expression (2) for recursive calculation and analysis, and the expression of the overall deviation of the tooth profile can be obtained. Finally, the expression of the overall deviation of the tooth profile is simulated by computer software, and the size of the tooth profile deviation at any point on the tooth profile surface can be obtained, and the distribution of the tooth profile deviation on the tooth surface can be intuitively seen.

[0075] Figure 8 Where H1 is the starting point of the measurement, O is the center of the tooth root circle, and r O is the root circle radius, connect H1O and intersect the root circle at point h1, point H on the tooth profile is the laser point that differs from the laser point at the measurement starting point by an angle of θ, l1 is the normal line at point H of the tooth profile, and a perpendicular line l2 is drawn through the center of the circle O to l1. The angle formed by l2 and the y-axis is the pressure angle α at point H of the tooth profile H , the distance from the laser probe to the tooth profile point H is L H , the distance from tooth profile point H to tooth root circle is y H .

[0076] from Fig. 9 It can be seen that the distance between two adjacent detection points is very small, so the tooth profile curve can be approximately represented by a small line segment connecting the two adjacent detection points, and the tooth profile error can also be obtained by calculating the distance from the midpoint of the two adjacent detection points to the theoretical tooth profile curve. This calculation method is more efficient and convenient.

[0077] The tooth profile overall deviation detection method proposed in the present invention first performs interpolation processing on the collected tooth profile points based on the differential evolution algorithm to refine the tooth profile point set and increase the calculation accuracy of the tooth profile deviation. Then, a three-dimensional space coordinate system is established with the gear as the center and the origin, and the refined tooth profile point set is converted into the form of three-dimensional coordinate points through the algorithm, and represented in the form of a three-dimensional data point matrix. Finally, according to the principle of 3×3 order non-uniform rational B-spline surface, the three-dimensional data points of the tooth profile are surface fitted to obtain the real tooth profile surface model of the gear to be tested. By accurately obtaining the tooth profile surface model, the tooth profile deviation at any point on the tooth surface of the gear to be tested can be calculated based on the tooth profile deviation analysis method on a single cross section. This tooth profile deviation calculation method can effectively avoid accidental errors, and the calculated deviation results are more accurate and reliable. In addition, the tooth profile deviation data set is further analyzed by computer software to obtain the distribution of the tooth profile deviation on the gear tooth surface, thereby providing a basis and help for the improvement and improvement of the process in the gear processing process.

[0078] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for measuring gears using a portable gear measuring device based on a line laser displacement sensor, characterized in that: The portable gear measuring device comprises a base (1), the base (1) is connected with a linear laser displacement sensor (5) which can be adjusted in position in the left-right, front-back and height directions, the base (1) on both sides of the linear laser displacement sensor (5) facing outward is rotatably connected with a clamping plate (2), one side of the two clamping plates (2) arranged opposite to each other is fixedly connected with a clamping claw (18), the base (1) between the two clamping claws (18) is connected with an electromagnet (17), the base (1) is connected with a sliding seat (6) which can slide left-right, the sliding seat (6) is connected with a fixed bracket (20) which can slide forward and backward, the upper end of the fixed bracket (20) is connected with a height-adjustable clamping plate (4), the lower part of the fixed bracket (20) is connected with a clamping plate (4) which can adjust the height of the clamping plate (4), and the lower part of the fixed bracket (20) is connected with a clamping plate (4) which can adjust the height of the clamping plate (4). A height-adjustable support block (23) is connected, the linear laser displacement sensor (5) is connected to the upper side of the support block (23), the clamping plate (4) presses the linear displacement sensor onto the support block (23), a fixed seat (7) is fixedly connected to the base (1) between the two clamping plates (2), a lower slider (9) is slidably connected to the fixed seat (7), a first adjusting screw (8) is rotatably connected to the fixed seat (7) below the base (1), the lower slider (9) is threadedly connected to the first adjusting screw (8), the sliding seat (6) is fixedly connected to the lower slider (9), an upper slider (22) is slidably connected to the sliding seat (6), and a second adjusting screw (21) is threadedly connected to the sliding seat (6) The upper slider (22) is threadedly connected to the second adjusting screw (21); a fixed platform (10) is provided above the sliding seat (6); the fixed platform (10) and the upper slider (22) are fixedly connected; the fixed bracket (20) is fixedly connected to the fixed platform (10); a bearing seat (16) is fixedly connected to the lower side of the base (1); two ends of the bearing seat (16) are rotatably connected to a first angle adjusting screw (11) and a second angle adjusting screw (14); the first angle adjusting screw (11) and the second angle adjusting screw (14) have opposite rotation directions; a first sliding groove and a second sliding groove are provided on the base (1); a first angle adjusting slider (15) is threadedly connected to the first angle adjusting screw (11); The first angle adjustment slider (15) can slide along the first slide groove, the second angle adjustment screw (14) is threadedly connected with the second angle adjustment slider (3), the second angle adjustment slider (3) can slide along the second slide groove, the clamping plate (2) is provided with an angle adjustment slide groove (301), the upper end of the first angle adjustment slider (15) is slidably connected to a corresponding clamping plate (2) through a corresponding angle adjustment slide groove (301), the upper end of the second angle adjustment slider (3) is slidably connected to another clamping plate (2) through another angle adjustment slide groove (301), the lower part of the fixed bracket (20) is fixed with a fixed plate, and a vertically arranged height adjustment screw (12) is rotatably connected to the fixed plate,The support block (23) is threadedly connected to the height adjustment screw (12); the upper end of the fixed bracket (20) is connected to a reset elastic member (13); at least one guide rod (19) is arranged on the lower side of the clamping plate (4); the guide rod (19) is slidably connected to the fixed bracket (20); the upper end of the reset elastic member (13) is connected to the clamping plate (4); when the linear laser displacement sensor (5) is between the support block (23) and the clamping plate (4), the reset elastic member (13) is in a stretched state; the steps include: The first angle adjustment screw (11) and the second angle adjustment screw (14) are rotated to open the two clamping jaws (18) until the gear to be measured can be just installed, the first angle adjustment screw (11) and the second angle adjustment screw (14) are stopped from rotating, the gear to be measured is placed between the two clamping jaws (18), the first angle adjustment screw (11) and the second angle adjustment screw (14) are continued to rotate to make the clamping jaws (18) just clamp the tooth profile of the gear to be measured, the electromagnet (17) is energized, and the gear to be measured is further adsorbed on the base (1); Rotate the second adjusting screw (21) to adjust the position of the linear laser displacement sensor (5) in the front-rear direction so that the gear to be measured is within the measuring range of the linear laser displacement sensor (5), and stop rotating the second adjusting screw (21); The first adjusting screw (8) is rotated to center the incident laser of the line laser displacement sensor (5), the first adjusting screw (8) is stopped from rotating, and the height adjusting screw (12) is rotated to achieve measurement of different tooth profile sections on the gear to be measured; The line laser displacement sensor (5) receives the reflected laser from the tooth profile surface and converts it into relative displacement data and coordinate data of each point on the tooth profile. The converted data is imported into a computer terminal to draw a corresponding tooth profile curve diagram and calculate and analyze the overall deviation of the gear tooth profile. The relative displacement and coordinate data conversion steps of each point on the tooth profile are as follows: set any point on the gear involute as , is the center of tooth root circle, is the tooth root circle radius, is the pressure angle at point H on the tooth profile, is the starting point of laser measurement, The laser point during the measurement process Angle to the starting laser point, Point on the involute The normal line at H1, the distance from H1 to the gear center is d1, d1= y1+ r0, connection , and intersects with the tooth root circle at point h1, y1 is the distance from point H1 to h1, r0 is the tooth root circle radius, and its coordinates can be expressed as , The laser point on the tooth profile The vertical distance to the lower end face of the gear, and point The angle between the gear and the starting point is Angle measurement laser point, connect HO, and intersect with the root circle at point ,point The distance to the center of the gear is d H , d H = y H +r0,y H is the distance from point H to h, and the three-dimensional coordinates of any point H on the tooth profile are .

2. The method for measuring gears using a portable gear measuring device based on a line laser displacement sensor according to claim 1, characterized in that: Tooth profile deviation at point i on the actual tooth profile line The normal distance to the theoretical tooth profile curve is , the total deviation F within the effective length of the tooth profile curve 总 , ; Assume that any point on the theoretical tooth profile The intersection point of the normal line at and the actual tiny line segment is ,but The tooth profile deviation at point is F H’ , the intersection point of the tiny line segment The coordinate equation of is, ， k is the point on the tooth profile The normal slope at the point, and according to the involute construction equation of the gear, it can be known that any point on the tooth profile The slope k of the normal at can be expressed as, , is the pressure angle at point G on the tooth profile; Actual tooth profile curve Tooth profile deviation at point F H’ for, ; Total tooth profile deviation F on any section 总 for , MAX(F H’ ) is the maximum tooth profile error value obtained on the calculated tooth profile section, MIN(F H’ ) is the minimum tooth profile error value obtained on the calculated tooth profile section.

3. The method for measuring gears using a portable gear measuring device based on a line laser displacement sensor according to claim 1, characterized in that: Select four adjacent coordinate points on the tooth profile section in sequence , and interpolation processing is performed based on the differential evolution algorithm, and the interpolation expression of the tooth profile coordinate point is deduced as follows: （1）， in, ; In the above formula, ; l is the interpolation point To point and Point The distance from the midpoint, For point The normal distance to the theoretical tooth profile line, and then The interpolation refinement of the tooth profile points can be achieved by iteratively calculating the interpolation search range conditions.

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