WO2019033581A1

WO2019033581A1 - Coaxiality measurement method and device for circular bore

Info

Publication number: WO2019033581A1
Application number: PCT/CN2017/109483
Authority: WO
Inventors: 王晗; 劳剑东; 陈新; 陈新度
Original assignee: 广东工业大学
Priority date: 2017-08-15
Filing date: 2017-11-06
Publication date: 2019-02-21
Also published as: CN107490349A

Abstract

A coaxiality measurement method for a circular bore. An end of an extensible arm (4) of a disc body (3) fits against an inner wall of a circular bore to be measured, such that the center of the disc body (3) can be regarded as the center of circle of a cross section at the position where the disc body (3) is located. Further, the center of the disc body (3) is provided with a reflective target (5). When a laser tracker (6) emits a laser to the reflective target (5), the reflective target (5) reflects the laser to generate a returned laser, and the laser tracker (6) receives and processes the returned laser to obtain three-dimensional coordinates of the center at a corresponding position. After moving the disc body (3), three-dimensional coordinates of the center of circle in more positions can be obtained by using the laser tracker (6), and finally data processing and analysis are performed according to the three-dimensional coordinates of the center of circle in the different positions, so as to obtain the coaxiality of the circular bore to be measured, realizing coaxiality measurement of the circular bore. A coaxiality measurement device for a circular bore is also disclosed.

Description

Method and device for measuring coaxiality of circular aperture

The present application claims priority to Chinese Patent Application No. 201710697609.2, entitled "Concentricity Measurement Method and Apparatus for Circular Aperture", filed on August 15, 2017, the entire contents of which are hereby incorporated by reference. The citations are incorporated herein by reference.

Technical field

The invention relates to the technical field of dimensional tolerance measurement, in particular to a method and a device for measuring coaxiality of a circular aperture.

Background technique

The coaxial measurement of long hollow round rods is one of the most basic measurement items in the field of machined parts tolerance measurement. It has a wide range of applications in the fields of precision instrumentation and even military manufacturing and inspection, installation and positioning. The cylindricity tolerance is used to control the degree to which the theoretical axis should be coaxially extracted from the measured axis and the reference axis. The cylindricity tolerance zone is a cylindrical surface area with a diameter that is a certain tolerance value and coaxial with the reference axis. The detection of the coaxiality is to find the maximum distance of the measured axis from the reference axis, and the double value is the coaxiality error.

At present, the coaxiality of the circular member is mainly measured by the indicator method. As shown in Fig. 1, the measured part is mounted between the two coaxial tips 1 of the precision indexing device, and the common axes of the two tips 1 are parallel. On the bottom surface 2 of the plate, the common axis is used as a measurement reference. In the axial measurement, the absolute value of the difference in readings measured on the positive section perpendicular to the reference axis is taken as the concentricity error in the section. Rotate the part to be tested, measure several sections according to the above method, and take the maximum value (absolute value) of the readings measured by each section as the coaxiality error of the part.

However, the above method can only be used to measure the coaxiality of the outer cylindrical surface of the circular rod member, and the coaxiality of the circular aperture opened on the workpiece is not applicable, and the coaxiality of the circular aperture is not yet compared. A good measuring device performs the measurement.

In summary, how to solve the problem of coaxiality measurement of a circular aperture has become a technical problem to be solved by those skilled in the art.

Summary of the invention

It is an object of the present invention to provide a method and apparatus for measuring the coaxiality of a circular aperture to achieve coaxiality measurement of a circular aperture.

In order to achieve the above object, the present invention provides a coaxial measurement method for a circular aperture, comprising the steps of:

Step S1: placing the disc body in a circular aperture to be detected, wherein the disc body is radially provided with a plurality of telescopic arms capable of expanding and contracting along the radial length of the disc body, the disc body a central position is provided with a reflective target, and an extension of the telescopic arm is adjusted such that an end of the telescopic arm fits an inner wall of the circular aperture to be detected;

Step S2: emitting laser light to the reflective target by a laser tracker, and the emission direction is at a preset angle with a central axis of the disk body;

Step S3: After the laser tracker receives the return laser reflected by the reflective target, the laser tracker processes the return laser to obtain a three-dimensional coordinate of a center of a corresponding position;

Step S4: by moving the position of the disc body, repeating steps S2 and S3 can obtain three-dimensional coordinates of a plurality of different positions;

Step S5: The data processing and analysis of the three-dimensional coordinates of the center of the plurality of different positions can be used to obtain the coaxiality of the circular aperture to be tested.

Compared with the background art, the coaxiality measurement method of the above circular aperture is such that the end of the telescopic arm of the disc body is fitted to the inner wall of the circular aperture to be tested, so that the center of the disc body can be considered as The center of the circle where the disc body is located is located, and the center of the disc body is provided with a reflective target. Therefore, when the laser is used to emit laser light to the reflective target, the emission direction is of course the central axis of the disc body. The preset angle, because the reflection of the reflective target will form a return laser, after receiving the return laser, the laser tracker processes to obtain the three-dimensional coordinates of the center of the corresponding position, and passes the laser after moving the position of the disk body. The tracker can obtain the three-dimensional coordinates of the center of more positions. Finally, according to the three-dimensional coordinates of the center of a plurality of different positions, the data can be processed and analyzed, and the coaxiality of the circular aperture to be tested can be obtained, thereby realizing the coaxiality measurement of the circular aperture. .

In addition, the present invention also provides a circular aperture coaxiality measuring device, including a disk body and a laser tracker;

The disc body is provided with a telescopic arm that can expand and contract along the radial length of the disc body in the radial direction. The number of the telescopic arms is at least two and is evenly arranged along the circumferential direction of the disc body, and a center of the disc body is provided with a reflective target;

The laser tracker is configured to emit laser light to the reflective target, and the emission direction is at a preset angle with a central axis of the disk body, and the laser tracker is further capable of receiving the reflective target reflection Returning the laser, and obtaining the three-dimensional coordinates of the center of the corresponding position in the circular aperture to be tested according to the returning laser.

Since the coaxiality measuring device of the above circular aperture follows the core idea of the coaxiality measuring method of the circular aperture described above, and the coaxiality measuring method of the circular aperture has the above technical effects, the circular aperture is used The coaxiality measuring device of the circular aperture of the coaxiality measuring method should also have corresponding technical effects, and will not be described herein.

Preferably, the end of the telescopic arm is further provided with a running mechanism for abutting against the inner wall of the circular aperture to be detected.

Preferably, the running mechanism includes a rolling surface for engaging a roller of the inner wall of the circular aperture to be tested, and each end of the telescopic arm is provided with at least two rollers arranged in parallel, and The roller of the roller is perpendicular to the centerline of the disk body.

Preferably, the running gear further comprises a walking track, and the walking track is sleeved on the rolling surfaces of the two outermost rollers.

Preferably, the running mechanism further includes a motor for driving the roller, and a reduction gear set is further disposed between the motor and the roller.

Preferably, a cavity of the disk body is provided with a first bevel gear concentric with the disk body and a second bevel gear meshing with the first bevel gear;

The back surface of the first bevel gear is provided with a first planar thread, and the arm surface of the telescopic arm is provided with a second planar thread that is threadedly engaged with the first plane;

The second bevel gear is connected to a drive mechanism.

Preferably, the drive mechanism is an adjustment knob disposed perpendicular to the axis of the second bevel gear.

Preferably, the number of the disc bodies is two, and two of the disc bodies are arranged coaxially.

Preferably, the two first bevel gears are fixedly connected.

DRAWINGS

1 is a schematic structural view of a coaxial measuring device for a conventional circular member;

2 is a schematic overall structural diagram of a coaxiality measuring device for a circular aperture according to an embodiment of the present invention;

3 is a schematic view showing the internal structure of a disk body according to an embodiment of the present invention;

4 is a schematic structural diagram of a telescopic arm according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a connection structure of two disc bodies according to an embodiment of the present invention; FIG.

FIG. 6 is a schematic structural diagram of a laser tracker according to an embodiment of the present invention.

In Figure 1 - Figure 6,

Top point 1, flat bottom surface 2, disk body 3, telescopic arm 4, reflective target 5, laser tracker 6, traveling mechanism 7, roller 8, walking track 9, motor 10, first bevel gear 12, second bevel gear 13. First planar thread 14, second planar thread 15, drive mechanism 16, power source 17, hollow cylindrical body 18, bearing 19.

Detailed ways

The core of the present invention is to provide a coaxial aperture measuring method and apparatus for circular aperture to achieve coaxial measurement of a circular aperture.

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments,

As shown in FIG. 2 to FIG. 6 , a method for measuring coaxiality of a circular aperture provided by an embodiment of the present invention includes the following steps:

Step S1: placing the disc body 3 in the circular aperture to be detected, and the disc body 3 is provided with a plurality of telescopic arms 4 capable of expanding and contracting along the radial length of the disc body 3 in the radial direction of the disc body 3, and the disc body 3 The central position is provided with a reflective target 5, and the extension of the telescopic arm 4 is adjusted such that the end of the telescopic arm 4 is fitted to the inner wall of the circular aperture to be detected;

Step S2: emitting laser light to the reflective target 5 through the laser tracker 6, and the emission direction is at a preset angle with the central axis of the disk body 3;

Step S3: When the laser tracker 6 receives the returning laser reflected by the reflective target 5, the laser is followed by The tracer 6 processes the return laser to obtain the three-dimensional coordinates of the center of the corresponding position;

Step S4: by moving the position of the disc body 3, repeating steps S2 and S3 can obtain three-dimensional coordinates of a plurality of different positions;

Step S5: By performing data processing analysis on the three-dimensional coordinates of a plurality of different positions, the coaxiality of the circular aperture to be tested can be obtained.

The method for measuring the coaxiality of the circular aperture is such that the end of the telescopic arm of the disc body is fitted to the inner wall of the circular aperture to be tested, so that the center of the disc body can be regarded as the section where the disc body is located. The center of the circle is located, and the center of the disk body is provided with a reflective target. Therefore, when the laser tracker emits laser light to the reflective target, the emission direction is of course preset with the central axis of the disk body, due to the reflection target. The reflection of the target will form a return laser. After receiving the return laser, the laser tracker will process the three-dimensional coordinates of the center of the corresponding position. After moving the position of the disk body, the laser tracker can obtain more positions. The three-dimensional coordinates of the center of the circle are finally processed according to the three-dimensional coordinates of the center of a plurality of different positions, and the coaxiality of the circular aperture to be tested can be obtained, thereby realizing the coaxiality measurement of the circular aperture.

It should be noted that the data processing and analysis of the center coordinates of a plurality of different positions may be embedded in the corresponding software program inside the laser tracker, thereby completing the corresponding data processing and obtaining the coaxiality of the circular aperture, or The three-dimensional coordinates of the center of the laser tracker are put into the corresponding data processing device for data processing, such as a computer equipped with corresponding data processing analysis software. In addition, it should be noted that the workpiece corresponding to the circular aperture to be tested may be a circular aperture formed by the axial position of the round bar member, or may be a circular aperture provided on the rectangular bar member. As long as the workpiece is opened with a circular aperture, the circular aperture generally refers to a large-aperture workpiece, because the disk body needs to be placed inside the circular aperture, the large aperture mentioned here. The size criterion is that the aperture that can be placed in the disk body can be called a large aperture.

Further, the present invention provides a coaxial measuring device for a circular aperture, comprising a disk body 3 and a laser tracker 6; the disk body 3 is radially provided with a length that can be stretched along the radial length of the disk body 3 The telescopic arm 4 has at least two telescopic arms 4 and is evenly arranged along the circumferential direction of the disc body 1, and the center of the disc body 3 is provided with a reflective target 5; the laser tracker 6 is used for reflection The target 5 emits a laser light, and the emission direction is at a predetermined angle with the central axis of the disk body 3, and the laser tracker 6 is also capable of receiving the reflection. The returning laser reflected by the target 5 obtains the three-dimensional coordinates of the center of the corresponding position in the circular aperture to be tested according to the returning laser.

In some specific embodiments, the end of the telescopic arm 4 may also be provided with a running mechanism 7 for abutting against the inner wall of the circular aperture to be inspected. By providing the running mechanism 7, the movement of the coaxiality measuring device of the circular aperture in the circular aperture to be tested is more convenient.

In a further embodiment, the running mechanism 7 may include a roller 8 having a rolling surface that can be fitted to the inner wall of the circular aperture to be tested, and each end of the telescopic arm 4 is provided with at least two rollers 8 arranged in parallel, and the roller The roller of 8 is perpendicular to the center line of the disk body 3. It should be understood that the above-mentioned roller is only a preferred example of the running mechanism of the embodiment of the present invention, and may be other traveling mechanisms commonly used by those skilled in the art, such as the structure of a smooth ski.

In still another embodiment, the traveling mechanism 7 further includes a walking crawler belt 9 that is sleeved on the rolling surfaces of the two outermost rollers 8 . By setting the walking track for transmission, the end of the telescopic arm is more smoothly fitted to the inner wall of the circular aperture to be tested, and the hard and hard contact is prevented from being scratched by the circular aperture to be measured.

In addition, the above-mentioned running mechanism 7 may further include a motor 10 for driving the roller 8, and the coaxiality measuring device of the circular aperture can be realized by the motor to automatically walk in the circular aperture to be tested, of course, those skilled in the art should be able to It is understood that in order to realize the driving function, the motor should also be connected with a corresponding power source 17. In order to make the motor control more convenient, the motor can also be controlled by the remote controller. Moreover, the reduction gear set 11 can be disposed between the motor 10 and the roller 8, and the speed of the direct output of the motor is decelerated by the reduction gear set, so that the walking distance control of the traveling mechanism is more convenient and easy to control. It should be noted that the above-mentioned traveling mechanism may be the above-mentioned motor driving mode or manual manual driving mode, but the embodiment of the present invention preferably adopts a motor driving method.

In some more specific embodiments, the telescopic arm 4 can be stretched along the radial length of the disk body 3 The specific structure may be that the first bevel gear 12 coaxial with the disk body 3 and the second bevel gear 13 meshing with the first bevel gear 12 are disposed in the cavity of the disk body 3; the first bevel gear 12 The back surface of the telescopic arm 4 is provided with a second planar thread 15 on the arm surface of the telescopic arm 4; the second bevel gear 13 is connected to the drive mechanism 16. When the arm surface of the telescopic arm is threadedly engaged with the back plane of the first bevel gear, when the first bevel gear rotates, the telescopic arm can achieve the same length extension or shortening. It is to be understood that the above is only an example of a specific structure in which the telescopic arm 4 can be expanded and contracted along the radial length of the disk body 3 in the embodiment of the present invention, and may also be other telescopic structures commonly used by those skilled in the art, such as The telescopic rod is a screw mechanism, and the screw rod is rotated by a screw mechanism with a vertically arranged bevel gear. When the bevel gear rotates, the screw rod rotates to realize elongation or shortening of the telescopic rod.

In a further embodiment, the drive mechanism 16 may be an adjustment knob disposed perpendicular to the axis of the second bevel gear 13. By rotating the adjustment knob, the second bevel gear rotates, thereby driving the first bevel gear to rotate, thereby driving the telescopic arm that is threadedly engaged with the first plane of the first bevel gear to be elongated or shortened. It should be understood that the above adjustment knob is only an example of the driving mechanism in the embodiment of the present invention, and may be other driving mechanisms commonly used by those skilled in the art, such as a motor drive.

In other specific embodiments, the number of the disc bodies 3 described above is preferably two, and the two disc bodies 3 are arranged coaxially. By arranging the disc bodies in two concentric arrangements, the coaxiality measuring device of the circular aperture is more stable and reliable when placed in the circular aperture to be tested, and passes through both ends of the circular aperture to be tested. At the same time, the laser tracker is arranged, so that the circular aperture coaxiality measuring device can measure the three-dimensional coordinates of the two centers when the position is in one position, so that the measurement efficiency is higher.

In a still further embodiment, a fixed connection may be disposed between the first bevel gears 12 disposed inside the two disc bodies, and when a first bevel gear is adjusted by being arranged in a fixed connection, The other first bevel gear will also rotate synchronously, so that only one drive mechanism can be arranged to achieve simultaneous adjustment of the telescopic arms of the two disc bodies. And the specific structure of the above fixed connection may be that the two first bevel gears are connected by the hollow cylindrical body 18, and the bearing 19 of the outer cylindrical surface of the hollow cylindrical body 18 is connected with the corresponding hole on the disk body, and the The connecting member is arranged to be hollowed out, so that the weight of the coaxial measuring device of the entire circular aperture is reduced, and the bearing body 19 is arranged to make the disc body closely match the hollow cylindrical body without affecting the synchronization of the two first bevel gears. Turn.

The above embodiments are only used to explain the technical solutions of the present application, and are not limited thereto; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still The technical solutions described in the embodiments are modified, or the equivalents of the technical features are replaced by the equivalents. The modifications and substitutions of the embodiments do not depart from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

A method for measuring coaxiality of a circular aperture, characterized in that it comprises the steps of:

Step S1: placing the disc body (3) in a circular aperture to be detected, and the disc body (3) is provided with a plurality of radially extending and extending along the radial length of the disc body (3). a telescopic arm (4), the center of the disc body (3) is provided with a reflective target (5), and the extension of the telescopic arm (4) is adjusted such that the end of the telescopic arm (4) The inner wall of the circular aperture to be detected is attached;

Step S2: emitting laser light to the reflective target (5) by a laser tracker (6), and the emission direction is at a preset angle with a central axis of the disk body (3);

Step S3: After the laser tracker (6) receives the return laser reflected by the reflective target (5), the laser tracker (6) processes the return laser to obtain a three-dimensional coordinate of the center of the corresponding position. ;

Step S4: by moving the position of the disc body (3), repeating steps S2 and S3 can obtain three-dimensional coordinates of a plurality of different positions;

Step S5: The data processing and analysis of the three-dimensional coordinates of the center of the plurality of different positions can be used to obtain the coaxiality of the circular aperture to be tested.
A coaxial measuring device for circular aperture, characterized in that it comprises a disc body (3) and a laser tracker (6);

The disc body (3) is provided with a telescopic arm (4) capable of expanding and contracting along the radial length of the disc body (3), and the number of the telescopic arms (4) is at least two. Arranging uniformly along the circumferential direction of the disc body (1), and the center of the disc body (3) is provided with a reflective target (5);

The laser tracker (6) is configured to emit laser light to the reflective target (5), and the emission direction is at a preset angle with a central axis of the disk body (3), the laser tracker ( 6) It is further capable of receiving a return laser reflected by the reflective target (5), and obtaining a three-dimensional coordinate of a center of a corresponding position in the circular aperture to be measured according to the return laser.
The circular aperture concentricity measuring device according to claim 2, wherein the end of the telescopic arm (4) is further provided with a running mechanism for abutting against an inner wall of the circular aperture to be detected ( 7).
A circular aperture coaxiality measuring apparatus according to claim 3, wherein said running mechanism (7) includes a rolling surface for engaging a roller of said inner wall of said circular aperture to be tested (8) The end of each of the telescopic arms (4) is provided with at least two rollers (8) arranged in parallel with the rollers, and the rollers of the rollers (8) are perpendicular to the disk body (3) Centerline.
A circular aperture coaxiality measuring apparatus according to claim 4, wherein said running mechanism (7) further comprises a walking track (9), said walking track (9) being sleeved on the outermost side The rolling surfaces of the two rollers (8).
A circular aperture concentricity measuring apparatus according to claim 3, wherein said running mechanism (7) further comprises a motor (10) for driving said roller (8), and said motor ( 10) A reduction gear set (11) is further provided between the roller (8).
The circular aperture concentricity measuring device according to claim 2, wherein the cavity of the disc body (3) is provided with a first concentricity with the disc body (3) a bevel gear (12) and a second bevel gear (13) meshing with the first bevel gear (12);

The back surface of the first bevel gear (12) is provided with a first planar thread (14), and the arm surface of the telescopic arm (4) is provided with a second planar thread that cooperates with the first planar thread (14) (15);

The second bevel gear (13) is connected to a drive mechanism (16).
A circular aperture concentricity measuring apparatus according to claim 7, wherein said drive mechanism (16) is an adjustment knob disposed perpendicular to an axis of said second bevel gear (13).
The circular aperture coaxiality measuring device according to claim 7, wherein the number of the disc bodies (3) is two, and two of the disc bodies (3) are concentric. Arrangement.
A circular aperture concentricity measuring device according to claim 9, wherein the two first bevel gears (12) are fixedly connected.