CN111238413A - A device and method for measuring the coaxiality of inner holes of shaft parts - Google Patents

Abstract

The invention discloses a device for measuring the coaxiality of inner holes of shaft parts, comprising a measuring platform, a part to be measured and a data acquisition and processing module. The measuring platform is provided with a driving module, a positioning module and a measuring module. The measurement module includes a laser displacement sensor, a measuring inner hole probe and a grating ruler fixed on the positioning module. The laser displacement sensor can be moved left and right through the positioning module, and the measuring inner hole probe can be moved up and down through the positioning module. The parts are placed on the driving module and rotated through the driving module. The laser displacement sensor, the measuring inner hole probe and the grating scale are connected with the signal of the quantity acquisition and processing module. The invention not only realizes the high-precision measurement of the coaxiality, but also greatly improves the Measurement efficiency, saving measurement costs.

Description

A device and method for measuring the coaxiality of inner holes of shaft parts

technical field

The invention relates to the technical field of measurement, in particular to a device and method for measuring the coaxiality of inner holes of shaft parts.

Background technique

At present, most of the coaxiality measurement of the inner hole of shaft parts still belongs to the contact measurement method, that is, the measurement tool and the fixture are used to clamp the part, the inspector manually rotates the part, and the measurement data point is measured through the contact between the probe and the surface of the part. Collect, and judge whether the coaxiality of the part meets the requirements according to the reading change of the indicator. The measurement results obtained using the above measurement methods are affected by various factors such as measurement devices, environmental disturbances, and manual operations, resulting in lower accuracy of the obtained measurement results. This contact measurement method has the following disadvantages:

1. Multiple sets of tooling and fixtures are required, and the cost is high. Due to the large changes in the dimensions of each component of the inner hole of shaft parts, the inner hole of shaft parts has various specifications, and multiple sets of measurement tooling and fixtures need to be customized according to different specifications, which increases the measurement cost.

2. The surface topography is complex and data point collection is difficult. The surface topography of the inner hole of shaft parts is relatively complex, and it is difficult for the probe to be in full contact with the measured surface at all times during the measurement process, resulting in the low accuracy of the data points of the current measured section. Moreover, the axial length of some specifications of parts is limited, resulting in a limited number of sections that can be used for measurement. If only individual sections are measured, the data point is single, which is only suitable for measuring concentricity, not coaxiality.

3. Manual rotation drive, low precision. It is difficult to achieve a stable and uniform speed state by manually controlling the rotation of the parts by the inspector, so there will be uneven distribution of data points, the accuracy is not easy to guarantee and the efficiency is low. Moreover, the manual rotation drive is easy to cause local runout of the parts, which directly affects the accuracy of the measurement data, thereby affecting the measurement results.

With the development of modern testing technology, optical measurement technology is more and more used in the detection of parts morphology and features. It combines the advantages of optics and electronics, and has non-contact, high precision, and anti-interference capabilities. The laser displacement sensor based on laser ranging is one of the typical representatives of optical measurement. It is widely used in research fields such as precision measurement and reverse engineering due to its high integration and good real-time performance. Compared with the traditional contact measurement method, the laser displacement sensor can obtain the feature information of the part surface more easily, which greatly improves the detection accuracy and effectively improves the detection efficiency.

SUMMARY OF THE INVENTION

In view of the above situation, the present invention provides a device and method for the coaxiality of an inner hole of a shaft part, which can achieve high-precision measurement of coaxiality, greatly improve measurement efficiency, and save measurement costs.

To achieve the above object, the present invention provides the following technical solutions:

A device for measuring the coaxiality of an inner hole of a shaft part, comprising a measuring platform, a part to be measured, and a data acquisition and processing module, the measuring platform is provided with a driving module, a positioning module and a measuring module, and the measuring module includes a fixed Laser displacement sensor, measuring inner hole probe and grating ruler on the positioning module, the laser displacement sensor can be moved left and right through the positioning module, the measuring inner hole probe can be moved up and down through the positioning module, and the part to be measured is placed in the drive The laser displacement sensor, the measuring inner hole probe and the grating ruler are connected with the signal of the quantity acquisition and processing module and are rotated on the module and through the driving module.

Preferably, the positioning module includes a profile frame and a guide rail arranged on the measuring platform, a laser displacement sensor is fixed at the top of the profile frame, and a slider is fixed at the bottom end of the profile frame, and the slide block is slidably connected to the guide rail. The profile frame can be driven to move left and right along the guide rail, and the measuring platform is also provided with a grating ruler on the side close to the guide rail.

Preferably, the positioning module includes a first up-down translation stage and a second up-down translation stage, the second up-down translation stage is provided with a top, and the position of the top corresponds to the end face of the part to be tested, and can pass through the second up-down translation stage. The second translation stage moves up and down, the first up and down translation stage is provided with a probe clamping device, the probe clamping device clamps the inner hole probe and can move up and down through the first up and down translation stage.

Preferably, the positioning module includes a pressing roller arranged on the test platform, and the pressing roller compresses the part to be tested.

Preferably, the drive module includes a motor support set on the measuring platform, a speed regulating motor is fixed on the motor support, the motor shaft of the speed regulating motor is connected with one end of the coupling, and the coupling The other end of the shaft is connected with the input shaft of the gear box, the gear box is connected with two friction wheels, and drives the two friction wheels to rotate, there are two pieces to be tested between the two friction wheels, and A corresponding angle can be rotated with the two friction wheels.

A method for measuring the coaxiality of an inner hole of a shaft part by the above device, comprising the following steps:

Step 1: Fix the measuring platform on the plane of the measuring site, fix the parts on the measuring platform, adjust the relative positions of each part at the same time, and build the whole measuring device;

Step 2: Put the part to be tested on the friction wheel, and try to ensure that it is horizontally placed, adjust the position of the center, and press the center of rotation of the shaft end of the part to be tested, and adjust the position of the pressure roller so that the pressure roller is pressed against the part to be measured. above;

Step 3: Turn on the power supply of the speed regulating motor, connect and initialize the laser displacement sensor, the measuring inner hole probe, the grating ruler and the data acquisition and processing module;

Step 4: Start the speed regulating motor, drive the part to be measured to rotate, move the laser displacement sensor to a certain measurement section of the measurement shaft section of the part to be measured, and send the distance data collected by the grating ruler to the data acquisition and processing module, and use the matching The coaxiality evaluation software processes the collected data, and obtains the center of the section through a certain algorithm;

Step 5: Move the laser displacement sensor to another section of the measuring shaft section of the part to be measured, obtain the circle centers of other multiple measuring sections by the same method as above, and fit the multiple circle centers into a straight line, which is the axis of the shaft section;

Step 6: Move the inner hole probe to measure the cross-section of different inner holes by the same method, you can get the center of the cross-section of multiple inner holes, and fit the multiple centers to get the axis of the inner hole, which can be obtained in the coaxiality evaluation software. Concentricity error results of the corresponding axes of the outer shaft and the inner hole.

Compared with the prior art, the beneficial effects of the present invention are:

The invention proposes to improve the existing inner hole coaxiality measurement method of shaft parts with laser displacement sensor and inner hole measurement probe as the core, combined with computer technology and error analysis technology, and build a system based on laser displacement The sensor's non-contact outer shaft-inner hole part coaxiality measurement system is completely controlled by the inspector through the computer for parts driving, data acquisition, result evaluation and other links in the measurement process, so as to achieve high-precision measurement of coaxiality At the same time, it greatly improves the measurement efficiency and saves the measurement cost.

Description of drawings

FIG. 1 is a schematic structural diagram of the present invention.

In the figure: 1-laser displacement sensor; 2-profile frame; 3-pressing roller; 4-first up and down translation stage; 5-measuring inner hole probe clamping device; 6-measuring inner hole probe; 7-guide rail; 8- Measuring platform; 9-motor support; 10-speed motor; 11-coupling; 12-gearbox; 13-friction wheel; 14-part to be measured; 15-top; 16-second up and down translation stage; 17 - grating ruler; 18-slider; 19-data acquisition and processing module.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

Referring to FIG. 1, the present invention provides a technical solution: a device for measuring the coaxiality of an inner hole of a shaft part, comprising a measuring platform 8, a part to be measured 14 and a data acquisition and processing module 19, on the measuring platform 8 A driving module, a positioning module and a measuring module are provided. The measuring module includes a laser displacement sensor 1 fixed on the positioning module, a measuring inner hole probe 6 and a grating ruler 17. The laser displacement sensor 1 can be moved left and right through the positioning module. The measuring inner hole probe 6 can be moved up and down through the positioning module, the part to be measured 14 is placed on the driving module and rotated by the driving module, and the laser displacement sensor 1 measures the distance from the laser probe to the surface of the part to be measured 14. , obtain the circle center of a certain measuring section of the measuring shaft section, measure the inner hole section of the part 14 to be measured by measuring the inner hole probe 6, obtain the circle center of the inner hole section, and measure the distance of the laser displacement sensor 1 moving on the measuring platform 8 with the grating ruler 17 Distance, the laser displacement sensor 1, the measuring inner hole probe 6 and the grating ruler 17 transmit the collected data to the quantity acquisition and processing module 19, and the quantity acquisition and processing module 19 can obtain the outer axis and inner axis through the coaxiality evaluation software. The result of the concentricity error of the hole corresponding to the axis.

Specifically, the drive module includes a motor support 9 disposed on the measurement platform 8 , a speed regulating motor 10 is fixed on the motor support 9 , and the motor shaft of the speed regulating motor 10 is connected to one end of the coupling 11 . The other end of the coupling 11 is connected with the input shaft of the gear box 12. The gear box 12 is connected with the two friction wheels 13 and drives the two friction wheels 13 to rotate. A part to be tested 14 is arranged between the wheels 13 and can rotate with the two friction wheels 13 by a corresponding angle.

The positioning module includes a profile frame 2 and a guide rail 7 arranged on the measuring platform 8. The top of the profile frame 2 is fixed with a laser displacement sensor 1, which is used to measure the distance between the laser probe of the laser displacement sensor 1 and the surface of the part 14 to be measured. The distance value, the bottom end of the profile frame 2 is fixed with a slider 18, the slider 18 is slidably connected with the guide rail 7, and can drive the profile frame 2 to move left and right along the guide rail 7. There is also a grating ruler 17 on the side to measure the distance that the laser displacement sensor 1 moves on the guide rail 7. After one measurement, move the laser displacement sensor 1 to another section of the shaft section of the part to be measured 14, and repeat the above steps to obtain other multiple Measure the center of the section, and fit multiple centers into a straight line, which is the axis of the shaft segment.

The positioning module includes a first up-down translation stage 4 and a second up-down translation stage 16, the second up-down translation stage 16 is provided with a top 15, and the position of the top 15 corresponds to the end face of the part to be tested 14, and The second translation stage 16 can be moved up and down, and according to the difference of the rotation center of the part to be tested 14, the top 16 can be driven to move up and down. A second translation stage slider is connected to the top, and the top 15 moves up and down through the second translation stage slider.

The first up-down translation stage 4 is provided with a probe clamping device 5, and the probe clamping device 5 clamps the measuring inner hole probe 6 to measure the center of the inner hole section of the part to be measured 14, and passes through the first upper and lower translation stage 4. The inner hole probe 6 is moved up and down to measure the cross-section centers of different inner holes, and the axes of the inner holes are obtained by fitting the multiple centers. A first translation stage slider is connected to the upper part, and the measuring inner hole probe 6 is moved up and down through the first translation stage slider.

The positioning module includes a pressing roller 3 arranged on the test platform 8 , and the pressing roller 3 presses the part to be tested 14 to prevent the part from jumping during the rotation process.

The steps when using the device are as follows:

Step 1: Fix the measurement platform 8 on the plane of the measurement site, fix the parts on the measurement platform 8, adjust the relative positions of each part at the same time, and build the entire measurement device;

Step 2: Place the part to be tested 14 on the friction wheel 13, and try to ensure that it is placed horizontally, adjust the position of the center 15, press the center of rotation of the shaft end of the part to be tested 14, and adjust the position of the pressing roller 3 so that the pressing roller 3 Press on the part to be tested 14;

Step 3: Turn on the power of the speed regulating motor 10, connect and initialize the laser displacement sensor 1, the measuring inner hole probe 6, the grating ruler 17 and the data acquisition and processing module 19;

Step 4: Start the speed regulating motor 10, drive the measured part 14 to rotate, move the laser displacement sensor 1 to a certain measurement section of the measured shaft section of the measured part 14, and send the distance data collected by the grating ruler 17 to data collection and processing Module 19: Process the collected data with the matching coaxiality evaluation software, and obtain the circle center of the section through a certain algorithm;

Step 5: Move the laser displacement sensor, 1 to another section of the measured shaft section of the part to be measured 14, obtain the circle centers of the other multiple measurement sections by the same method as above, and fit the multiple circle centers into a straight line. shaft axis;

Step 6: Move the inner hole probe 6 in the same way to measure the cross-sections of different inner holes, and obtain the circle centers of multiple inner hole sections, and fit the multiple circle centers to obtain the axis of the inner hole, which can be used in the coaxiality evaluation software. The results of the coaxiality error of the corresponding axes of the outer shaft and the inner hole are obtained.

Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, and substitutions can be made in these embodiments without departing from the principle and spirit of the invention and modifications, the scope of the present invention is defined by the appended claims and their equivalents.

Claims (6)

1. a device for measuring the coaxiality of the inner hole of shaft parts, is characterized in that, comprises measuring platform, part to be measured and data acquisition and processing module, described measuring platform is provided with driving module, positioning module and measuring module, The measuring module includes a laser displacement sensor, a measuring inner hole probe and a grating ruler fixed on the positioning module. The laser displacement sensor can be moved left and right through the positioning module, and the measuring inner hole probe can be moved up and down through the positioning module. The part to be measured is placed on the driving module and rotated by the driving module, and the laser displacement sensor, the measuring inner hole probe and the grating ruler are signal-connected with the quantity acquisition and processing module. 2 . The device for measuring the coaxiality of an inner hole of a shaft part according to claim 1 , wherein the positioning module comprises a profile frame and a guide rail arranged on the measuring platform, and a laser displacement is fixed at the top of the profile frame. 3 . A sensor, a slider is fixed at the bottom end of the profile frame, the slider is slidably connected with the guide rail, and can drive the profile frame to move left and right along the guide rail, and a grating ruler is also provided on the side close to the guide rail on the measuring platform. 3 . The device for measuring the coaxiality of an inner hole of a shaft part according to claim 2 , wherein the positioning module comprises a first up-down translation stage and a second up-down translation stage, and the second up-down translation stage is mounted on the second up-down translation stage. 4 . There is a top, the position of the top corresponds to the end face of the part to be tested, and can be moved up and down through the second translation stage. The first up and down translation stage is provided with a probe clamping device, and the probe clamping device clamps Holds the inner hole probe and can move up and down through the first up and down translation stage. 4 . The device for measuring the coaxiality of an inner hole of a shaft part according to claim 3 , wherein the positioning module comprises a pressing roller arranged on the test platform, and the pressing roller compresses the part to be tested. 5 . 5 . The device for measuring the coaxiality of an inner hole of a shaft part according to claim 4 , wherein the drive module comprises a motor support arranged on the measuring platform, and a speed control is fixed on the motor support. 6 . The motor, the motor shaft of the speed regulating motor is connected with one end of the coupling, the other end of the coupling is connected with the input shaft of the gearbox, the gearbox is connected with the two friction wheels, and drives the The two friction wheels rotate, and two pieces to be tested are arranged between the two friction wheels, and can rotate by a corresponding angle with the two friction wheels. 6. a method for measuring the coaxiality of the inner hole of shaft parts with the described device of claim 5, is characterized in that, comprises the steps: Step 1: Fix the measuring platform on the plane of the measuring site, fix the parts on the measuring platform, adjust the relative positions of each part at the same time, and build the whole measuring device; Step 2: Put the part to be tested on the friction wheel, and try to ensure that it is horizontally placed, adjust the position of the center, and press the center of rotation of the shaft end of the part to be tested, and adjust the position of the pressure roller so that the pressure roller is pressed against the part to be measured. above; Step 3: Turn on the power supply of the speed regulating motor, connect and initialize the laser displacement sensor, the measuring inner hole probe, the grating ruler and the data acquisition and processing module; Step 4: Start the speed regulating motor, drive the part to be measured to rotate, move the laser displacement sensor to a certain measurement section of the measurement shaft section of the part to be measured, and send the distance data collected by the grating ruler to the data acquisition and processing module, and use the matching The coaxiality evaluation software processes the collected data, and obtains the center of the section through a certain algorithm; Step 5: Move the laser displacement sensor to another section of the measuring shaft section of the part to be measured, obtain the circle centers of other multiple measuring sections by the same method as above, and fit the multiple circle centers into a straight line, which is the axis of the shaft section; Step 6: Move the inner hole probe to measure the cross-section of different inner holes by the same method, you can get the center of the cross-section of multiple inner holes, and fit the multiple centers to get the axis of the inner hole, which can be obtained in the coaxiality evaluation software. Concentricity error results of the corresponding axes of the outer shaft and the inner hole.

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