阅读说明：本技术 一种基于光机耦合的非接触式轴系回转精度测试方法 (Non-contact type shafting rotation precision testing method based on optical-mechanical coupling ) 是由 甄龙 廖祖平 严情木 马强 于 2021-07-29 设计创作，主要内容包括：本发明涉及光电角度传感器技术领域,提供一种基于光机耦合的非接触式轴系回转精度测试方法,包括：步骤1,搭建非接触式轴系回转精度测试系统；所述非接触式轴系回转精度测试系统,包括：调整机构、圆光栅和测量仪器；待测试的轴系安装在调整机构底部,所述调整机构上安装有圆光栅；所述圆光栅上方配置测量仪器；步骤2,进行轴系非随机回转误差测量,包括步骤201至步骤202：步骤201,调整圆光栅,使圆光栅的中心调整至与轴系的回转中心重合,将圆光栅的平面调整至于轴系的回转中心线垂直；步骤202,计算轴系非随机回转误差；步骤3,进行轴系随机回转误差测量。本发明能够提高非接触式轴系回转精度测试的精确性和可靠性。(The invention relates to the technical field of photoelectric angle sensors, and provides a non-contact shafting rotation precision test method based on optical-mechanical coupling, which comprises the following steps: step 1, building a non-contact type shafting rotation precision test system; the non-contact shafting gyration precision test system includes: the device comprises an adjusting mechanism, a circular grating and a measuring instrument; a shaft system to be tested is arranged at the bottom of an adjusting mechanism, and a circular grating is arranged on the adjusting mechanism; a measuring instrument is arranged above the circular grating; step 2, performing shafting non-random rotation error measurement, including steps 201 to 202: step 201, adjusting a circular grating to enable the center of the circular grating to be adjusted to coincide with the rotation center of a shaft system, and adjusting the plane of the circular grating to be perpendicular to the rotation center line of the shaft system; step 202, calculating a non-random rotation error of a shafting; and step 3, measuring the random rotation error of the shafting. The invention can improve the accuracy and reliability of the non-contact type shafting rotation precision test.)

1. A non-contact shafting rotation precision test method based on optical-mechanical coupling is characterized by comprising the following steps:

step 1, building a non-contact type shafting rotation precision test system;

the non-contact shafting gyration precision test system includes: the device comprises an adjusting mechanism (2), a circular grating (3) and a measuring instrument (4); a shafting (1) to be tested is arranged at the bottom of an adjusting mechanism (2), and a circular grating (3) is arranged on the adjusting mechanism (2); a measuring instrument (4) is arranged above the circular grating (3);

step 2, performing shafting non-random rotation error measurement, including steps 201 to 202:

step 201, adjusting a circular grating (3) to enable the center of the circular grating (3) to be adjusted to coincide with the rotation center of a shaft system (1), and adjusting the plane of the circular grating (3) to be perpendicular to the rotation center line of the shaft system (1);

step 202, calculating a non-random rotation error of the shafting, including step 2021 to step 2022:

step 2021, calculating an axial rotation error of a shafting;

step 2022, calculating a radial rotation error of a shafting;

step 3, measuring the shafting random rotation error, comprising the steps 301 to 302:

301, selecting a plurality of test points within a circle of the circular grating (3), measuring for multiple times at each test point by using a measuring instrument (4), and recording the axial variation delta a and the radial variation delta b of each test point;

step 302, determining a random rotation error of a shafting (1): the maximum value of the axial variation is used as the axial gyration error of the shafting (1), and the maximum value of the radial variation is used as the radial gyration error of the shafting (1).

2. The method for testing the rotation precision of the shafting in a non-contact manner based on the optical-mechanical coupling according to claim 1, wherein the adjusting mechanism (2) comprises: the device comprises a shafting connecting plate (201), a grating mounting seat (202), an axial adjusting structure (204) and a radial adjusting structure (203);

the shafting connecting plate (201) is used for being connected with a shafting (1) to be tested, and the grating mounting seat (202) is connected with the circular grating (3);

axial adjusting structures (204) are uniformly arranged on the shafting connecting plate (201) in the circumferential direction, and the axial adjusting structures (204) are arranged between the shafting connecting plate (201) and the grating mounting seat (202);

the side wall of the grating mounting seat (202) is uniformly distributed with radial adjusting structures (203) in the circumferential direction.

3. The non-contact shafting rotation precision test method based on the optical-mechanical coupling according to claim 1 or 2, wherein the circular grating (3) has an axial measurement reference (301) and a radial measurement reference (302).

4. The method for testing the rotation accuracy of the shafting in a non-contact manner based on the optical-mechanical coupling according to claim 1 or 2, wherein in step 201, the method for adjusting the circular grating (3) comprises:

step 2011, rotating the shafting (1), observing a test pattern of the circular grating (3) by using the measuring instrument (4), and judging the radial shaking amount delta A and the axial shaking amount delta B of the circular grating (3) within a circle;

step 2012, recording the maximum value maxA and the minimum value minA of the radial shaking amount of the circular grating (3) in a circle range;

step 2013, recording the maximum value maxB and the minimum value minB of the axial shaking amount of the circular grating (3) in a circle range;

step 2014, adjusting the radial position and the axial position of the circular grating (3) by using the adjusting mechanism (2);

and 2015, sequentially repeating the steps 2011 to 2014 until the radial shaking amount is the minimum value and the axial shaking amount is the minimum value after multiple adjustments, and stopping the adjustment.

5. The method for testing the slewing precision of the shafting in the non-contact mode based on the optical-mechanical coupling of the claim 4, wherein the step 2021 of calculating the axial slewing error of the shafting comprises the following steps:

taking axial shaking amount data of the primary shafting (1) after adjustment, recording data of the test points along the circumferential direction, and fitting a plane by using the data of the test points;

then calculating the positive distance maxC and the negative distance minC between the test point and the fitting plane;

calculating the axial rotation error of the shafting (1) as follows: maxC-minC.

6. The method for testing the revolving accuracy of the shafting in the non-contact mode based on the optical-mechanical coupling of the claim 5, wherein the step 2022, the step of calculating the radial revolving error of the shafting comprises the following steps:

taking radial shaking amount data of the primary shafting (1) after adjustment, recording data of the test points along the circumferential direction, and fitting an arc by using the data of the test points;

then calculating the positive distance maxD and the negative distance minD between the test point and the fitting arc;

calculating the axial rotation error of the shafting (1) as follows: maxD-minD.

Technical Field

The invention relates to the technical field of photoelectric angle sensors, in particular to a non-contact type shafting rotation precision testing method based on optical-mechanical coupling.

Background

The shaft system is a main conversion element of the photoelectric angle sensor and is a carrier for converting mechanical displacement to optical quantity, and the rotation precision of the shaft system directly influences the motion characteristic of the whole sensor in the rotation measurement process. Therefore, the shafting rotation precision detection technology is not only a means for evaluating the process characteristics such as shafting manufacturing precision and rigidity, but also a basis for analyzing the shafting characteristics on the overall performance of the sensor, and is a process problem which must be overcome in product engineering.

At present, mechanical displacement measurement equipment is adopted for detecting the rotation precision of a shafting, and a shafting test datum plane is directly measured to obtain displacement variation to measure the precision of the shafting. The shafting test device has the technical problems of insufficient precision of mechanical measurement equipment, introduction of machining errors, measurement errors generated by contact measurement, insufficient shafting test precision and the like.

Disclosure of Invention

The invention mainly solves the technical problem of insufficient measurement precision caused by measurement errors caused by machining and contact stress due to contact measurement adopted by shafting rotation precision detection in the prior art, and provides a non-contact type shafting rotation precision test method based on optical-mechanical coupling so as to improve the accuracy and reliability of non-contact type shafting rotation precision test.

The invention provides a non-contact type shafting rotation precision test method based on optical-mechanical coupling, which comprises the following steps:

step 1, building a non-contact type shafting rotation precision test system;

the non-contact shafting gyration precision test system includes: the device comprises an adjusting mechanism, a circular grating and a measuring instrument; a shaft system to be tested is arranged at the bottom of an adjusting mechanism, and a circular grating is arranged on the adjusting mechanism; a measuring instrument is arranged above the circular grating;

step 2, performing shafting non-random rotation error measurement, including steps 201 to 202:

step 201, adjusting a circular grating to enable the center of the circular grating to be adjusted to coincide with the rotation center of a shaft system, and adjusting the plane of the circular grating to be perpendicular to the rotation center line of the shaft system;

step 202, calculating a non-random rotation error of the shafting, including step 2021 to step 2022:

step 2021, calculating an axial rotation error of a shafting;

step 2022, calculating a radial rotation error of a shafting;

step 3, measuring the shafting random rotation error, comprising the steps 301 to 302:

step 301, selecting a plurality of test points within a circle of the circular grating, performing multiple measurements on each test point by using a measuring instrument, and recording the axial variation delta a and the radial variation delta b of each test point;

step 302, determining a shafting random rotation error: and taking the maximum value of the axial variation as the axial rotation error of the shafting, and taking the maximum value of the radial variation as the radial rotation error of the shafting.

Further, the adjustment mechanism includes: the device comprises a shafting connecting plate, a grating mounting seat, an axial adjusting structure and a radial adjusting structure;

the shafting connecting plate is used for being connected with a shafting to be tested, and the grating mounting seat is connected with the circular grating;

axial adjusting structures are uniformly arranged on the shafting connecting plate in the circumferential direction and are arranged between the shafting connecting plate and the grating mounting seat;

the side wall of the grating mounting seat is uniformly distributed with radial adjusting structures in the circumferential direction.

Further, the circular grating has an axial measurement reference and a radial measurement reference.

Further, in step 201, the method for adjusting the circular grating includes:

step 2011, rotating a shafting, observing a test pattern of the circular grating by using a measuring instrument, and judging a radial shaking amount delta A and an axial shaking amount delta B of the circular grating in a circle range;

step 2012, recording the maximum value maxA and the minimum value minA of the radial shaking amount of the circular grating in a circle range;

step 2013, recording the maximum value maxB and the minimum value minB of the axial shaking amount of the circular grating in a circle range;

step 2014, adjusting the radial position and the axial position of the circular grating by using an adjusting mechanism;

and 2015, sequentially repeating the steps 2011 to 2014 until the radial shaking amount is the minimum value and the axial shaking amount is the minimum value after multiple adjustments, and stopping the adjustment.

Further, in step 2021, calculating the axial rotation error of the shafting includes the following steps:

taking axial shaking amount data of the primary shafting after adjustment, recording data of the test points along the circumferential direction, and fitting a plane by using the data of the test points;

then calculating the positive distance maxC and the negative distance minC between the test point and the fitting plane;

calculating the axial rotation error of a shafting as follows: maxC-minC.

Further, in step 2022, calculating the radial rotation error of the shafting includes the following processes:

taking radial shaking amount data of the primary shafting after adjustment, recording data of the test points along the circumferential direction, and fitting an arc by using the data of the test points;

then calculating the positive distance maxD and the negative distance minD between the test point and the fitting arc;

calculating the axial rotation error of a shafting as follows: maxD-minD.

The invention provides a non-contact type shafting rotation precision testing method based on optical-mechanical coupling, which takes a high-precision circular grating 3 arranged on a shafting 1 as a measuring reference, and uses high-end equipment such as a high-precision full-automatic image measuring instrument and the like to online detect the variation of the geometric optical axis of the circular grating in the shafting rotation motion process, namely the radial shaking quantity of the circular grating and the axial shaking quantity of the circular grating, so as to evaluate the rotation precision of a flexible shafting. The high-precision circular grating is used as a measuring reference, the machining precision of the high-precision circular grating is higher than that of the traditional machining precision, the whole process does not contact the measuring reference, and the accuracy and the stability of the measuring reference are guaranteed. The testing process is completed in a cycle from optical testing to mechanical adjustment to optical testing, the testing method of optical-mechanical coupling is realized, repeated adjustment is performed in the testing process, and the measuring error is reduced. The invention has the characteristics of accuracy, automation, intellectualization, digitalization and online detection, changes the traditional mechanical contact type detection method, can meet the requirements of high-precision, high-efficiency, low-cost and reliable detection of a product shaft system, and lays a process foundation for the engineering of products.

Drawings

FIG. 1 is a flow chart of the implementation of the non-contact shafting rotation precision testing method based on optical-mechanical coupling according to the present invention;

FIG. 2 is a schematic structural diagram of a non-contact shafting rotation precision testing system provided by the present invention;

FIG. 3 is a schematic structural view of an adjustment mechanism provided by the present invention;

FIG. 4 is a schematic structural view (side view) of a circular grating provided by the present invention;

fig. 5 is a schematic structural diagram (top view) of a circular grating provided by the present invention.

Reference numerals: 1. a shaft system; 2. an adjustment mechanism; 3. a circular grating; 4. a measuring instrument; 201. a shafting connecting plate; 202. a grating mounting seat; 203. a radial adjustment structure; 204. an axial adjustment structure; 301. an axial measurement reference; 302. and measuring the reference in the radial direction.

Detailed Description

In order to make the technical problems solved, technical solutions adopted and technical effects achieved by the present invention clearer, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some but not all of the relevant aspects of the present invention are shown in the drawings.

As shown in fig. 1, a non-contact shafting rotation precision testing method based on optical-mechanical coupling according to an embodiment of the present invention includes:

step 1, a non-contact type shafting rotation precision testing system is set up.

As shown in fig. 2, the non-contact type shafting rotation precision testing system includes: the device comprises an adjusting mechanism 2, a circular grating 3 and a measuring instrument 4.

A shafting 1 to be tested is arranged at the bottom of an adjusting mechanism 2, and a circular grating 3 is arranged on the adjusting mechanism 2; and a measuring instrument 4 is arranged above the circular grating 3. The measuring instrument 4 is not in contact with other structures, and non-contact measurement is realized.

As shown in fig. 3, the adjusting mechanism 2 includes: shafting connecting plate 201, grating mount 202, axial adjustment structure 204 and radial adjustment structure 203. The shafting connecting plate 201 is used for being connected with a shafting 1 to be tested, and the grating mounting seat 202 is connected with the circular grating 3. The axial adjusting structures 204 are uniformly arranged on the shafting connecting plate 201 in the circumferential direction, the axial adjusting structures 204 are arranged between the shafting connecting plate 201 and the grating mounting seat 202, and the axial adjusting structures 204 can adjust the relative position relationship between the shafting connecting plate 201 and the grating mounting seat 202 to realize the adjustment of the axial position of the circular grating 3. The radial adjusting structures 203 are uniformly distributed on the side wall of the grating mounting seat 202 in the circumferential direction, and the radial adjusting structures 203 can adjust the radial position of the circular grating 3.

As shown in fig. 4 and 5, the circular grating 3 has an axial measuring datum 301 and a radial measuring datum 302, and the axial measuring datum 301 is a testing surface of the circular grating 3, and the distance from the circular grating surface to the measuring instrument 4 can be tested by the measuring instrument 4. The radial measurement reference 302 is a test pattern processed by the circular grating, and the radial offset of the circular grating 3 can be tested by the measuring instrument 4.

The measuring instrument 4 can adopt a high-precision full-automatic image measuring instrument, and can detect the variation of the geometric optical axis of the circular grating 3 in the rotation process of the shafting 1 on line, namely the radial shaking quantity of the circular grating 3 and the axial shaking quantity of the circular grating.

And 2, measuring the non-random rotation error of the shafting.

The non-random rotation error of the shafting means that the shafting shakes and swings repeatedly in the rotation process. The test results for each week when measured using the measuring instrument 4 remained unchanged. The method for measuring the non-random rotation error of the shaft system is the full-circumference continuous multi-circle measurement of the circular grating. The specific process of step 2 includes steps 201 to 202:

step 201, adjusting the circular grating 3 to make the center of the circular grating 3 adjusted to coincide with the rotation center of the shaft system 1, and adjusting the plane of the circular grating 3 to be perpendicular to the rotation center line of the shaft system 1. The adjusting method comprises the following steps:

in step 2011, the shafting 1 is rotated, the measuring instrument 4 is used to observe the test pattern of the circular grating 3, and the radial shaking amount Δ a and the axial shaking amount Δ B of the circular grating 3 within a circle are determined.

Step 2012, recording the maximum value maxA and the minimum value minA of the radial shaking amount of the circular grating 3 in a circle range.

And step 2013, recording the maximum value maxB and the minimum value minB of the axial shaking amount of the circular grating 3 in a circle range.

In the present embodiment, the machining accuracy of the circular grating 3 is very high as a reference, and therefore: the maximum value and the minimum value of the radial shaking amount of the circular grating 3 are positioned at opposite sides, namely the connection line of the two positions passes through the center of the circular grating; the radial shaking amount Δ a ═ maxA-minA. The maximum value and the minimum value of the axial shaking amount of the circular grating 3 are positioned at opposite sides, namely the connection line of the two positions passes through the center of the circular grating; the axial shaking amount Δ B is maxB-minB. .

Step 2014, adjusting the radial position and the axial position of the circular grating 3 by using the adjusting mechanism 2:

the radial wobble amount of the circular grating 3 is adjusted by the radial adjustment structure 203 of the adjustment mechanism 2, the circular grating 3 is adjusted toward the center, the position where the adjustment direction is the maximum value of the radial wobble amount is moved toward the position where the adjustment direction is the minimum value, and the adjustment amount is (maxA-minA)/2.

The axial shaking amount of the circular grating 3 is adjusted to be horizontal by adjusting the axial adjusting structure 204 of the structure 2, the adjusting direction is the middle position between the maximum value and the minimum value of the axial shaking amount, and the adjusting amount is (maxB-minB)/2.

Step 2015, sequentially repeating steps 2011 to 2014 until the radial shaking amount (Δ a ═ maxA-minA) is the minimum value and the axial shaking amount (Δ B ═ maxB-minB) is the minimum value after the adjustment is performed for multiple times, and stopping the adjustment; namely, the adjustment is already carried out to the ideal state, and the reason that the adjustment cannot be carried out to the more ideal state is caused by the non-random error existing in the shafting.

The measurement is carried out again after the adjustment, the test is carried out again, the adjustment is carried out again, and the adjustment precision is improved. After the position of the circular grating 3 is adjusted by the method, the maximum value and the minimum value of the radial shaking amount and the maximum value and the minimum value of the axial shaking amount of the ideal shafting 1 should be the same. Even if different, the radial shaking amount and the axial shaking amount of the circular grating should be continuously changed in value, namely, continuously changed from the maximum value to the minimum value, and then continuously changed from the minimum value to the maximum value, and the steps are repeated. When discontinuous change occurs, the shafting is indicated to be non-ideal and has shafting rotation error.

Step 202, calculating a non-random rotation error of the shafting.

Step 2021, calculating the axial rotation error of the shafting.

And taking the adjusted test data of the primary shafting 1, namely the axial shaking amount data, recording the data of the test points along the circumferential direction, fitting a plane by using the data of the test points, and then calculating the positive distance maxC and the negative distance minC between the test points and the fitted plane. The axial rotation error of the shafting 1 is calculated as follows: maxC-minC.

In the present embodiment, the algorithm of fitting the plane is, for example, the least squares method.

Step 2022, calculating the radial rotation error of the shafting.

And taking the adjusted test data of the primary shafting 1, namely the radial shaking amount data, recording the data of the test points along the circumferential direction, fitting an arc by using the data of the test points, and calculating the positive distance maxD and the negative distance minD between the test points and the fitted arc. The axial rotation error of the shafting 1 is calculated as follows: maxD-minD.

In the present embodiment, an algorithm for fitting an arc is, for example, a least squares method.

And step 3, measuring the random rotation error of the shafting.

The random rotation error of the shaft system 1 refers to irregular shaking and swinging of the shaft system 1 in the rotation process. When the measuring instrument 4 is used for measuring, the test results of each circle are different, and the results of multiple measurements on the same circumferential position are also different. The method for testing the random rotation error of the shafting is to respectively measure a plurality of test points in the full circumference range for a plurality of times. The specific process is as follows:

step 301, selecting a plurality of test points within a circle of the circular grating 3, performing multiple measurements on each test point by using the measuring instrument 4, and recording the axial variation delta a and the radial variation delta b of each test point.

Step 302, determining a random rotation error of a shafting 1: the maximum value of the axial variation is taken as the axial gyration error of the shafting 1, and the maximum value of the radial variation is taken as the radial gyration error of the shafting 1.

The axial rotation error of the shafting 1 is as follows: max (Δ a);

the radial rotation error of the shafting 1 is as follows: max (Δ b);

in case of an ideal shafting, the axial and radial variation of each test point should be kept constant when the measurement is repeated, i.e. Δ a is 0 and Δ b is 0. The variation is caused by random rotation error of the shafting.

The invention relates to a non-contact type shafting rotation precision test method based on optical-mechanical coupling, which takes a high-precision circular grating 3 arranged on a shafting 1 as a measurement reference, and uses high-end equipment such as a high-precision full-automatic image measuring instrument and the like to online detect the variation quantity of the geometric optical axis of the circular grating in the shafting rotation motion process, namely the radial shaking quantity of the circular grating and the axial shaking quantity of the circular grating, so as to evaluate the rotation precision of a flexible shafting.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: modifications of the technical solutions described in the embodiments or equivalent replacements of some or all technical features may be made without departing from the scope of the technical solutions of the embodiments of the present invention.