CN205940484U - Measure device of linear guide precision - Google Patents

Abstract

The utility model discloses a device for measuring the accuracy of a linear guide rail. The device comprises a measuring frame body, a measuring sensor arranged on the measuring frame body and a high-precision flat ruler. The high-precision flat ruler and the measured guide rail both pass through the Measuring frame body, the number of measuring sensors is seven, wherein the first measuring sensor and the second measuring sensor are respectively aligned with the top surface and side of the high-precision ruler, the third measuring sensor is aligned with the reference side of the measured guide rail, and the fourth The measurement sensor is aligned with the reference bottom surface of the tested guide rail, the fifth measurement sensor is aligned with the non-reference side of the measured guide rail, the sixth measurement sensor and the seventh measurement sensor are aligned with the top surface of the measured guide rail at the same time, and the two measurement sensors are about The center plane of the tested rail is symmetrical. The utility model adopts the combination of absolute measurement and relative measurement, and uses a non-contact measurement sensor to obtain high-precision measurement values, and has the characteristics of good versatility and high efficiency.

Description

A device for measuring the accuracy of linear guide rail

technical field

The utility model belongs to the field of linear guide rail measurement, in particular to a device for measuring the accuracy of a linear guide rail.

Background technique

At present, the accuracy measurement of linear guideways is mostly measured by manual measurement or contact sensors. When manually measuring the parallelism of the guideway raceways, the guideway is clamped on the fixture of the measuring plate, and the table base is aligned with the side reference surface of the guideway and the installation plane of the guideway. , and align the meter head with the raceway surface of the guide rail, and then move the meter base to measure. The difference between the measured maximum and minimum values is the parallelism error of the guide rail raceway. High quality requirements and poor repeatability of measurement results; China Utility Model Publication No. CN103438839A, titled: A linear guide rail accuracy automatic measurement device and its measurement method, the patent introduces the use of a pneumatic contact sensor to measure the guide rail accuracy, the sensor is in the contact Pneumatic components are installed on the type sensor so that it does not touch the measured object during the non-working period. During measurement, the standard slider equipped with this type of sensor moves at a certain distance to realize the height and parallelism of the measured guide rail. However, this method needs to make corresponding standard guide rails and standard sliders when measuring different types of guide rails, which increases economic costs and maintenance costs.

To sum up, the various guideway accuracy measuring instruments currently used cover few measurement items, especially for the measurement of raceway-related accuracy, and the measurement efficiency, measurement accuracy, and repeatability need to be improved.

Utility model content

The purpose of the utility model is to provide a device for measuring the accuracy of a rolling linear guideway.

The technical solution to realize the purpose of this utility model is: a device for measuring the accuracy of a linear guide rail, including a measuring frame, a measuring sensor arranged on the measuring frame, and a high-precision flat ruler, and the high-precision flat ruler and the measured guide rail Both pass through the measuring frame, and the number of measuring sensors is seven, in which the first measuring sensor and the second measuring sensor are respectively aligned with the top surface and side of the high-precision ruler, and the third measuring sensor is aligned with the reference side of the measured guide rail , the fourth measuring sensor is aimed at the reference bottom surface of the tested guide rail, the fifth measuring sensor is aimed at the non-reference side of the tested guide rail, the sixth measuring sensor and the seventh measuring sensor are simultaneously aimed at the top surface of the tested guide rail, the two The measuring sensor is symmetrical about the center plane of the rail under test.

A kind of non-contact measurement method based on above-mentioned device, comprises the following steps:

Step 1. Construct a coordinate system, specifically: the X-axis along the length direction of the tested guide rail, the Y-axis along the width direction of the tested guide rail, and the Z-axis along the vertical direction to the bottom surface of the tested guide rail;

Step 2. The measuring platform moves relative to the tested guide rail, and the measuring sensor collects the data of the tested guide rail in real time during the movement process.

Step 3. Separating and processing the data collected by the measuring sensor, and dividing the data into measurement data when moving along the X-axis and measurement data when moving along the Z-axis;

Step 4, performing motion compensation on the measurement data of the measurement sensor;

Step 5, processing the measurement data of the third measurement sensor and the fifth measurement sensor when they move along the Z axis, to obtain the radius and center of the raceway arc on the section of the guide rail;

Step 6. Calculate the accuracy error of the tested guide rail, specifically including raceway radius, raceway parallelism, raceway straightness, side reference straightness, bottom reference straightness, equal height, equal width and twist.

Compared with the prior art, the utility model has the remarkable advantages as follows: 1) when the device of the utility model is used for measurement, it does not need to be fixed with multiple bolts, it can be directly placed and automatically fixed by the cam, the test efficiency is high, and the installation is convenient. The installation cost is reduced to a certain extent; 2) The measuring device of the present invention can use multiple sensors to measure data and process and analyze during the movement process, which is a dynamic precision measurement, which is more in line with the actual measurement situation; 3) The utility model is being carried out The test is easy to operate, high in efficiency, strong in repeatability, economical and practical, and conducive to popularization; 4) Through the timely measurement of the laser displacement sensor, it reflects the comprehensive and accurate dimensional data of the tested guide rail, and the test data is continuous and reliable; 5 ) The measurement method of the utility model is in line with international standards, and is more advanced and reliable.

Description of drawings

Figure 1 is a sensor layout diagram of a device for measuring the accuracy of rolling linear guides.

detailed description

With reference to Fig. 1, a device for measuring the accuracy of a linear guide rail includes a measuring frame body 1, a measuring sensor arranged on the measuring frame body and a high-precision flat ruler 3, and the high-precision flat ruler 3 and the measured guide rail 4 pass through The measuring frame body 1 has seven measuring sensors, wherein the first measuring sensor 2-1 and the second measuring sensor 2-2 are respectively aligned with the top surface and the side of the high-precision ruler 3, and the third measuring sensor 2-3 Align the reference side of the tested guide rail 4, the fourth measurement sensor 2-4 is aligned with the reference bottom surface of the tested guide rail 4, the fifth measurement sensor 2-5 is aligned with the non-reference side of the tested guide rail 4, and the sixth measurement sensor 2 - 6 and the seventh measuring sensor 2 - 7 are aimed at the top surface of the tested guide rail 4 at the same time, and the two measuring sensors are symmetrical about the central plane of the tested guide rail 4 .

The seven measurement sensors are located on the same plane.

The measured guide rail 4 and the high-precision ruler 3 are parallel to each other.

The position X _t when the measuring frame 4 moves is obtained by a position sensor, where t is a time variable.

A kind of non-contact measurement method based on above-mentioned device, comprises the following steps:

Step 1. Construct a coordinate system, specifically: the X-axis along the length direction of the tested guide rail, the Y-axis along the width direction of the tested guide rail, and the Z-axis along the vertical direction to the bottom surface of the tested guide rail;

Step 2: The measuring platform moves relative to the tested guide rail 4, and the measuring sensor collects data of the tested guide rail 4 in real time during the movement.

When the measuring platform moves relative to the measured guide rail 4, it includes linear motion along the X-axis and linear motion along the Z-axis. The above two-axis motions are independent of each other. Whenever the motion along the X-axis reaches the set distance S _i =i L, Stop the movement in this direction, start the reciprocating movement along the Z axis, the stroke is 2h, and move like this until the set stroke is reached; where L is the unit movement interval, h is the height of the measured guide rail, (i=1,2... m-1), m is interval number; Wherein the first measuring sensor 2-1, the second measuring sensor 2-2, the third measuring sensor 2-3, the fourth measuring sensor 2-4, the fifth measuring sensor 2-5 , The measurement points aligned by the sixth measurement sensor 2-6 and the seventh measurement sensor 2-7 are P ₁ , P ₂ , P ₃ , P ₄ , P ₅ , P ₆ , P ₇ respectively; 7 measurement sensors record in real time The measurement distances are S ₁ {s ₁ (x _t ,z _t )}, S ₂ {s ₂ (x _t ,z _t )}, S ₃ {s ₃ (x _t ,z _t )}, S ₄ { s ₄ (x _t ,z _t )}, S ₅ {s ₅ (x _t ,z _t )}, S ₆ {s ₆ (x _t ,z _t )}, S ₇ {s ₇ (x _t ,z _t )}.

Step 3. Separating and processing the data collected by the measurement sensor, and dividing the data into measurement data when moving along the X-axis and measurement data when moving along the Z-axis.

When separating and processing the data collected by the measurement sensor, the formula Separate the coordinate sets PX ₃ , PX ₄ , PX ₅ , PX ₆ , and PX ₇ of the measuring points P ₃ , P ₄ , P ₅ , P ₆ , and P ₇ moving along the X-axis, where n is the number of measuring points;

later by Separate out the point sets PY _i ³ , PY _i ⁵ (i=1,2...m) of the moving parts along the Z-axis when the measurement points P ₃ and P ₅ are in the section of the guide rail corresponding to x _t =i·L, where, t is a time variable, and α and β are given positive values. For example, in a certain measurement, the unit of x _t is millimeter, and the unit of z _t is also millimeter, then the value of α is 1, and the value of β is 1.

Step 4. Motion compensation is performed on the measurement data of the measurement sensor. Specifically:

Assuming that the base coordinate system of the high-precision ruler base is X _w Y _w Z _w O, and the coordinate system platform of the measuring platform is X _t Y _t Z _t O, then the coordinates of the measurement point in the base coordinate system can be obtained through coordinate transformation:

The coordinates of the measurement point pointed by the third measurement sensor 2-3 are P ₃ =(X ^T , (S ₃ −S ₂ ) ^T , S ₁ ^T ),

The coordinates of the measurement point pointed by the fourth measurement sensor 2-4 are P ₄ =(X ^T , S ₂ ^T , (S ₁ +S ₄ ) ^T ),

The coordinates of the measurement point pointed by the fifth measurement sensor 2-5 are P ₅ =(X ^T ,(S ₅ +S ₂ ) ^T ,S ₁ ^T ),

The coordinates of the measurement point pointed by the sixth measurement sensor 2-6 are P ₆ =(X ^T , S ₂ ^T , (S ₆ −S ₁ ) ^T ),

The coordinates of the measurement point pointed by the seventh measurement sensor 2-7 are P ₇ =(X ^T , S ₂ ^T , (S ₇ −S ₁ ) ^T ).

Step 5: Process the measurement data of the third measurement sensor 2-3 and the fifth measurement sensor 2-5 when they move along the Z-axis, and obtain the radius and center of the raceway arc on the section of the guide rail. Specifically:

Use the image tool to display the cross-sectional profile images of PY _i ³ and PY _i ⁵ (i=1,2...m), and then select the upper and lower raceway profile intervals Finally, the least squares fitting circle algorithm is used to process the data in the contour interval of the raceway, and the arc radius of the upper and lower raceways is obtained. Center coordinates

Step 6. Use relevant algorithms to calculate and evaluate the accuracy error of the tested guide rail, including raceway radius, raceway parallelism, raceway straightness, side reference straightness, bottom reference straightness, equal height, equal width, and distortion. Specifically:

The radius of the guide rail is obtained by the formula R=average[R ₁ ,R ₂ ,........,R _n-1 ,R _n ];

The straightness error of the side reference and bottom reference of the guide rail is calculated from the coordinate set PX ₃ and PX ₄ by the straightness error algorithm provided in the national standard GBT 11336-2004;

The straightness of the guide rail raceway is calculated by the spatial straightness error algorithm provided in the national standard GBT 11336-2004 for the coordinate set Q _i (a _i , b _i , c _i );

The parallelism error of the guide rail raceway relative to the side and bottom references of the guide rail itself is calculated by the following method: take Let T=QEF, the parallelism error of the guide rail raceway relative to the side and bottom surface of the guide rail itself is calculated from the coordinate set T by the space straightness error algorithm provided in the national standard GBT 11336-2004;

The parallelism error between the guide rail raceways is calculated by the following method: take The parallelism error of the upper and lower raceways on one side of the guide rail is calculated by the space straightness error algorithm provided in the national standard GBT 11336-2004 to the coordinate system Calculated, the parallelism of the upper or lower raceway of the guide rail is determined by the space straightness error algorithm provided in the national standard GBT 11336-2004 to the coordinate system Calculated;

The rail contour is calculated by inferred;

The calculation of the equal width of the guide rail is obtained by the maximum value in the second column of the matrix W=PX ₃ +PX ₅ ;

Rail twist is given by the formula It can be obtained that L _w is the distance between the sixth measuring sensor 2-6 and the seventh measuring sensor 2-7 along the width direction of the measured guide rail 4 .

It can be seen from the above that a device and non-contact measuring method for measuring the accuracy of linear guide rails of the present utility model can measure the accuracy of X-type or O-type linear guide rails, through five non-contact measuring sensors, XZ two-axis The moving slide, XZ axis position sensor and other necessary devices form a coordinate measuring system, and two non-contact measuring sensors are used to align the narrow and long high-precision marble rulers on both sides for motion compensation of the moving slide, and laser interference Measuring the straightness of high-precision marble flat ruler can get better compensation effect. The measuring platform can measure the absolute coordinate value of the measuring point on the surface of the measured guide rail relative to the measuring platform. The movement of the measuring platform includes the feed motion along the direction of the measured guide rail and the feed motion along the vertical direction. Absolute measurement Perform data processing on the obtained coordinate point set with the principle of relative measurement, and obtain the accuracy value of the measured guide rail, including raceway radius, raceway parallelism, raceway straightness, side reference straightness, bottom reference straightness, contour, Monospaced, distorted. The utility model adopts the combination of absolute measurement and relative measurement, and uses a non-contact measurement sensor to obtain high-precision measurement values, and has the characteristics of good versatility and high efficiency.

Claims (4)

1. A device for measuring the accuracy of a linear guide rail, characterized in that it comprises a measuring frame [1], a measuring sensor arranged on the measuring frame and a high-precision flat ruler [3], the high-precision flat ruler [3] and the measured guide rail [4] pass through the measuring frame [1], and the number of measuring sensors is seven, wherein the first measuring sensor [2-1] and the second measuring sensor [2-2] are respectively aligned with high-precision The top and side surfaces of the ruler [3], the third measuring sensor [2-3] is aligned with the reference side of the measured guide rail [4], and the fourth measuring sensor [2-4] is aligned with the measured guide rail [4]. The bottom surface of the reference, the fifth measurement sensor [2-5] is aligned with the non-reference side of the measured guide rail [4], the sixth measurement sensor [2-6] and the seventh measurement sensor [2-7] are aligned with the measured guide rail at the same time The top surface of [4], the two measuring sensors are symmetrical about the center plane of the measured guide rail [4]. 2. The device for measuring the accuracy of a linear guideway according to claim 1, wherein the seven measuring sensors are located on the same plane. 3. The device for measuring the accuracy of a linear guide rail according to claim 1, characterized in that the measured guide rail [4] and the high-precision ruler [3] are parallel to each other. 4. The device for measuring the accuracy of a linear guide rail according to claim 1, characterized in that the position X _t of the measuring frame [4] is obtained by a position sensor when it moves, where t is a time variable.