In-situ biaxial testing machine centering device and calibration method

Abstract

The present invention belongs to the field of test and calibration technology, and discloses an in-situ biaxial testing machine centering device and calibration method, wherein the centering device comprises a motor connector, a laser instrument clamping mechanism, a laser instrument, a fixed plate, a stud bolt rotating shaft, and a rotating connector; a one-dimensional centering mode and a two-dimensional centering mode are formed through different connections, which are respectively used to realize the coaxial installation of two relative motor shafts and the coplanar installation of four motor shafts; the calibration method is to install the centering device after the motor shaft, emit laser by the laser instrument, and identify the position of the laser point by the laser receiving target, so as to perform error analysis; according to the error analysis, one of the motor shafts is used as a reference to adjust the other three motor shafts to realize centering installation, and finally realize that the first motor shaft, the second motor shaft, the third motor shaft, and the fourth motor shaft are precisely in the same installation plane, and the first motor shaft and the third motor shaft, the second motor shaft and the fourth motor shaft are precisely coaxial, with a simple structure and convenient operation.

Description

Technical Field

[0001] The present invention belongs to the technical field of testing and calibration, and in particular relates to a centering device for an in-situ biaxial testing machine, and a calibration method based on the device. Background Art

[0002] In actual service, engineering structures are often subjected to multiaxial loading conditions. Even during uniaxial loading, certain key locations of the structure may experience multiaxial loading due to local constraints. Therefore, developing an in-situ biaxial testing machine and conducting related tests to study the deformation and damage of engineering structures under complex loads is of great significance for guiding engineering practice.

[0003] A key issue during the installation of an in-situ biaxial testing machine is ensuring that the four mutually perpendicular axes of the testing machine are in the same plane and that the two opposing axes are in the same straight line, so as to avoid introducing uncontrollable bending moments during the test, which would affect the accuracy of the test results.

[0004] Existing testing machine alignment devices only address one-dimensional alignment of two relative axes, while ignoring two-dimensional alignment on a plane. Therefore, there is an urgent need to develop a two-dimensional alignment device for in-situ biaxial testing machines to assist in the precise installation of the testing machine and ensure accurate in-situ biaxial testing. Summary of the Invention

[0005] The present invention aims to solve the technical problems related to alignment during the installation of an in-situ biaxial testing machine, and provides an in-situ biaxial testing machine alignment device and calibration method, which can accurately assist in the alignment installation of the four motor shafts during the installation of the testing machine. At the same time, it has a simple structure and is easy to operate.

[0006] In order to solve the above technical problems, the present invention is implemented through the following technical solutions:

[0007] According to one aspect of the present invention, there is provided an in-situ biaxial testing machine alignment device, comprising a motor connector, a laser instrument clamping mechanism, a laser instrument, a fixed plate, a stud bolt rotating shaft, and a rotating connector; the motor connector, the laser instrument clamping mechanism, and the laser instrument are connected to form a one-dimensional alignment mode for achieving coaxial installation of two relative motor shafts; the motor connector, the fixed plate, the stud bolt rotating shaft, the rotating connector, the laser instrument clamping mechanism, and the laser instrument are connected to form a two-dimensional alignment mode for achieving coplanar installation of four motor shafts;

[0008] The motor connector is sleeved on the outside of the motor shaft and has an interference fit with the motor shaft, and the motor connector and the motor shaft are fixed by a first locking bolt to achieve coaxial connection between the motor connector and the motor shaft;

[0009] The laser instrument clamping mechanism includes a connecting portion and a clamping portion, wherein the connecting portion is used to be threadedly connected to the motor connector or the rotating connector, and the clamping portion is used to clamp the laser instrument. The clamping portion is externally sleeved with two fixing buckles. By adjusting the tightness of the two fixing buckles, the laser instrument can be adjusted to be coaxially connected to the laser instrument clamping mechanism;

[0010] The laser emitted by the laser instrument can be received by a laser receiving target installed on another motor shaft, and the laser receiving target is coaxially arranged with the motor shaft to which it is connected; the laser receiving target can identify the position of the laser point and output the coordinate value for error analysis;

[0011] The rotating connector is coaxially arranged with the laser instrument clamping mechanism, one end of which is used for threaded connection with the laser instrument clamping mechanism in a two-dimensional alignment mode, and the other end of which is used for passing the stud bolt shaft; the rotating connector can rotate around the stud bolt shaft, and after being rotated into place, the rotating connector and the stud bolt shaft are fixed by a second locking bolt;

[0012] The stud bolt shaft passes through the rotating connector and the fixed plate, and both ends of the stud bolt shaft are respectively threadedly connected to hand nuts;

[0013] The two fixed plates are respectively located between the two hand-tightening nuts and the rotating connector, and are symmetrically arranged with the axis of the rotating connector as the center line; the fixed plates are fixedly connected to the motor connector and the stud bolt shaft;

[0014] Thus, the motor connector is connected to the rotating connector through the two fixed plates and the stud bolt shaft, and the rotating connector is connected to the laser instrument through the laser instrument clamping mechanism, forming a two-dimensional alignment mode; the motor connector is directly connected to the laser instrument through the laser instrument clamping mechanism, forming a one-dimensional alignment mode.

[0015] Furthermore, the motor connector is a cylinder, including a hollow section and a solid section that are integrally connected; the end face of the hollow section is open, and is used to be sleeved on the outside of the motor shaft and interference fit with the motor shaft; the side wall of the hollow section is provided with a first threaded hole, and the axis of the first threaded hole is arranged along the radial direction of the motor connector, for installing the first locking bolt; the end face of the solid section is provided with a second threaded hole and two third threaded holes, and the second threaded hole is coaxial with the motor connector, and is used to connect the laser clamping mechanism in a one-dimensional centering mode; the two third threaded holes are symmetrically arranged on both sides of the second threaded hole, and the axis of the third threaded hole is parallel to the axis of the motor connector, and are respectively used to connect the two fixed plates.

[0016] Furthermore, the first locking bolt passes through the first threaded hole formed in the motor connector and is threadedly connected, and the end of the first locking bolt abuts against the motor shaft.

[0017] Furthermore, the connecting part of the laser instrument clamping mechanism is provided with an external thread for threaded connection with the rotating connecting part or the motor connecting part; the clamping part of the laser instrument clamping mechanism is provided with a notch, and the expansion and retraction of the inner diameter of the clamping part are achieved through the notch to achieve clamping of the laser instrument.

[0018] Furthermore, one end of the rotating connecting member is provided with an internal thread, which is used to connect the laser clamping mechanism; the other end is provided with a radial through hole and two fourth threaded holes, and the axis of the radial through hole is used to pass through the stud bolt rotating shaft; the two fourth threaded holes are respectively provided on both sides of the radial through hole for installing the second locking bolt.

[0019] Furthermore, the middle part of the stud bolt shaft is a smooth axis, which is used to pass through the rotating connecting member and the fixed plate; external threads are provided at both ends of the stud bolt shaft for installing the hand-tightening nut; and the stud bolt shaft is provided with a full-length keyway extending along the axial direction, which is used to cooperate with the key structure provided on the fixed plate.

[0020] Furthermore, the second locking bolt passes through the rotating connector and is threadedly connected to the rotating connector, and its end abuts against the stud bolt shaft; the axis of the second locking bolt is arranged along the radial direction of the rotating connector and is perpendicular to the axis of the radial through hole of the rotating connector; the two second locking bolts are arranged with an axis angle of 180°.

[0021] Furthermore, the fixed plate includes a plate body and a connecting column connected to one end of the plate body, the axis of the connecting column is parallel to the axis of the motor connector; the connecting column is provided with an external thread for threaded connection with the motor connector; the plate body is provided with a circular through hole, the circular through hole is used to allow the end of the stud bolt shaft to pass through; a key structure is provided on the inner side of the circular through hole, the key structure is used to cooperate with the keyway of the stud bolt shaft.

[0022] According to another aspect of the present invention, a method for calibrating an in-situ biaxial testing machine based on the aforementioned centering device is provided, wherein the second, third, and fourth motor shafts are adjusted to achieve centering installation, with any selected first motor shaft as a reference; wherein the first motor shaft is opposite to the third motor shaft, and the second motor shaft is opposite to the fourth motor shaft;

[0023] The steps include:

[0024] (1) installing the centering device on the first motor shaft according to the one-dimensional centering mode, and installing the laser receiving target on the third motor shaft;

[0025] (2) rotating the laser instrument clamping mechanism so that it drives the laser instrument to rotate twice around the motor connector, collecting the laser point position three times on the laser receiving target, and obtaining the actual center (X0, Y0) and actual diameter D of the laser receiving area;

[0026] (3) determining whether the actual diameter D of the laser receivable area is within the allowable error range; if not, proceeding to step (4); if so, aligning the laser instrument mounted on the first motor shaft with the coaxial line of the first motor shaft, proceeding to step (5);

[0027] (4) After adjusting the tightness of the two fixing buckles, repeat steps (2) and (3);

[0028] (5) At this time, the centering device of the one-dimensional centering mode is debugged and step (2) is repeated; it is determined whether the actual center (X0, Y0) and the actual diameter D of the laser receivable area are within the error tolerance range; if not, step (6) is performed; if so, the third motor shaft is coaxial with the first motor shaft 1, and step (7) is performed;

[0029] (6) After adjusting the installation position of the third motor shaft, repeat step (5);

[0030] (7) At this point, the alignment installation of the third motor shaft is completed, and the alignment device is adjusted from a one-dimensional alignment mode to a two-dimensional alignment mode and installed on the first motor shaft;

[0031] (8) rotating the laser instrument clamping mechanism so that it drives the laser instrument to rotate twice around the rotating connector, collecting the laser point position three times on the laser receiving target, and obtaining the actual center (X0, Y0) and actual diameter D of the laser receiving area;

[0032] (9) Determine whether the actual diameter D of the laser receivable area is within the error tolerance range; if not, proceed to step (10); if so, the coaxial line of the laser instrument clamping mechanism and the rotating connecting member is determined, and proceed to step (11);

[0033] (10) After adjusting the tightness of the two fixing buckles, repeat steps (8) and (9);

[0034] (11) determining whether the actual center (X0, Y0) of the laser receivable area is within the allowable error range; if not, proceeding to step (12); if so, determining whether the laser instrument mounted on the first motor shaft is coaxial with the first motor shaft, proceeding to step (13);

[0035] (12) After adjusting the tightness of the two hand nuts, repeat step (11);

[0036] (13) At this time, the centering device of the two-dimensional centering mode is debugged, the laser receiving target is installed on the second motor shaft, the second locking bolt is loosened, and the rotating connector is rotated around the stud bolt shaft until the laser emitted by the laser instrument is directed toward the laser receiving target and as close to the center of the laser receiving target as possible, and then the second locking bolt is tightened;

[0037] (14) Repeat step (8) and determine whether the actual center (X0, Y0) and actual diameter D of the laser receivable area are within the allowable error range; if not, proceed to step (15); if so, the coplanar installation of the second motor shaft is completed, and proceed to step (16);

[0038] (15) After adjusting the installation position of the second motor shaft, repeat step (14);

[0039] (16) Install the laser receiving target on the fourth motor shaft, loosen the second locking bolt, rotate the rotating connector around the stud shaft until the laser emitted by the laser instrument is directed toward the laser receiving target and as close to the center of the laser receiving target as possible, and then tighten the second locking bolt;

[0040] (17) Repeat step (8) and determine whether the actual center (X0, Y0) and actual diameter D of the laser receivable area are within the allowable error range; if not, proceed to step (18); if so, the coplanar installation of the fourth motor shaft is completed, and proceed to step (19).

[0041] (18) After adjusting the installation position of the fourth motor shaft, repeat step (17).

[0042] (19) At this time, the first motor shaft, the second motor shaft, the third motor shaft, and the fourth motor shaft are coplanar, and the first motor shaft and the third motor shaft are coaxial; the centering device is adjusted from a two-dimensional centering mode to a one-dimensional centering mode, and is installed on the second motor shaft;

[0043] (20) Repeat step (2) and determine whether the actual diameter D of the laser receivable area is within the error tolerance range; if not, proceed to step (21); if so, the laser instrument installed on the second motor shaft is coaxial with the second motor shaft, and proceed to step (22);

[0044] (21) After adjusting the tightness of the two fixing buckles, repeat step (20);

[0045] (22) At this time, the centering device of the one-dimensional centering mode is debugged and step (2) is repeated; it is determined whether the actual center (X0, Y0) and the actual diameter D of the laser receivable area are within the error allowable range; if not, step (23) is performed; if so, the fourth motor shaft is coaxial with the second motor shaft; at this point, the first motor shaft, the second motor shaft, the third motor shaft, and the fourth motor shaft are in the same installation plane, and the first motor shaft and the third motor shaft, the second motor shaft and the fourth motor shaft are coaxial, and the installation is completed;

[0046] (23) After adjusting the installation position of the fourth motor shaft, repeat step (22);

[0047] The adjustment of the installation position of the fourth motor shaft in this step is limited to adjustment within the plane, which refers to the plane where the first motor shaft, the second motor shaft, the third motor shaft, and the fourth motor shaft are coplanar.

[0048] Furthermore, the laser instrument clamping mechanism is rotated twice, and three laser point positions are collected on the laser receiving target as (X1, Y1), (X2, Y2), and (X3, Y3); the actual center (X0, Y0) of the laser receivable area and the three actual output positions (X1, Y1), (X2, Y2), and (X3, Y3) satisfy the following relationship:

[0049] (X1-X0) 2 +(Y1-Y0) 2 =(X2-X0) 2 +(Y2-Y0) 2 =(X3-X0) 2 +(Y3-Y0) 2

[0050] Furthermore, the actual diameter D of the laser receivable area is calculated based on the actual center (X0, Y0) of the laser receivable area:

[0051]

[0052] The standard center of the laser receiving area (X0 s ,Y0 s ) on the laser receiving target has the corresponding coordinate (0,0), and the standard diameter D s =0; the actual circle center (X0, Y0) of the laser receiving area and the standard circle center (X0 s ,Y0 s ) and the actual diameter D and the standard diameter D s Compare and conduct error analysis.

[0053] The beneficial effects of the present invention are:

[0054] The centering device of the present invention has a compact structure, is small and portable, is easy to install and easy to operate, and can realize arbitrary switching between one-dimensional centering mode and two-dimensional centering mode, thereby meeting the centering and debugging of various forms of uniaxial or biaxial in-situ tension and compression testing machines; its calibration method can quantify the centering test results by emitting laser and identifying the laser point position by the laser receiving target in one-dimensional centering mode and two-dimensional centering mode; combined with error analysis, the centering and debugging of the in-situ testing machine can be accurately completed, which can not only realize the precise coaxial installation of two relative motor shafts, but also realize the precise coplanar installation of four motor shafts. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] Figure 1 This is a schematic diagram of the assembly of the two-dimensional centering mode of the in-situ biaxial testing machine centering device provided by the present invention;

[0056] Figure 2 This is a schematic diagram of the assembly of a one-dimensional centering mode of the in-situ biaxial testing machine centering device provided by the present invention;

[0057] Figure 3 This is a schematic structural diagram of the motor connector in the device provided by the present invention;

[0058] Figure 4 This is a schematic structural diagram of the fixed plate in the device provided by the present invention;

[0059] Figure 5 This is a schematic diagram of the connection between the fixed plate and the motor connector in the device provided by the present invention;

[0060] Figure 6 This is a schematic structural diagram of the stud bolt shaft in the device provided by the present invention;

[0061] Figure 7 This is a schematic structural diagram of the rotating connecting member in the device provided by the present invention;

[0062] Figure 8 This is a schematic structural diagram of the laser instrument clamping mechanism in the device provided by the present invention;

[0063] Figure 9 This is a schematic structural diagram of the laser receiving target in the device provided by the present invention;

[0064] Figure 10 This is a schematic diagram of the laser receiving area on the laser receiving target in the device provided by the present invention.

[0065] In the above figure: 1. Motor shaft; 2. Motor connecting part, 201. Hollow section, 202. Solid section, 203. First threaded hole, 204. Second threaded hole, 205. Third threaded hole; 3. First locking bolt; 4. Fixed plate, 401. Plate body, 402. Connecting column, 403. Circular through hole, 404. Key structure; 5. Stud bolt rotating shaft, 501. Optical axis, 502. External thread, 503. Full-length keyway; 6. Hand nut; 7. Second locking bolt; 8. Rotating connecting part, 801. Internal thread, 802. Radial through hole, 803. Fourth threaded hole; 9. Laser instrument clamping mechanism, 901. Connecting part, 902. Clamping part; 10. Laser instrument; 11. Fixing buckle; 12. Laser receiving target. DETAILED DESCRIPTION

[0066] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0067] like Figure 1 and Figure 2 As shown, the present invention provides an in-situ biaxial testing machine alignment device, which is mainly composed of a motor connector 2, a fixed plate 4, a stud shaft 5, a rotating connector 8, a laser clamping mechanism 9, and a laser 10. Different installation methods can be used to achieve a two-dimensional alignment mode or a one-dimensional alignment mode. Based on the fact that light propagates in a straight line, in the one-dimensional alignment mode, the laser 10 emits a laser, the laser receiving target 12 identifies the laser point position, and performs error analysis to achieve the alignment installation of two relative motor shafts 1. In the two-dimensional alignment mode, the laser 10 emits a laser, the laser receiving target 12 identifies the laser point position, and performs error analysis to achieve the coplanar installation of the four motor shafts 1.

[0068] like Figure 3 As shown, the motor connector 2 is a cylinder, including a hollow section 201 and a solid section 202 that are integrally connected. The end face of the hollow section 201 is open, and is used to be sleeved on the outside of the motor shaft 1 and have an interference fit with the motor shaft 1. A first threaded hole 203 is provided on the side wall of the hollow section 201. The axis of the first threaded hole 203 is arranged along the radial direction of the motor connector 2, and is used to install the first locking bolt 3. A second threaded hole 204 is provided at the center of the end face of the solid section 202. The second threaded hole 204 is coaxial with the motor connector 2 and is used to be threadedly connected to the laser clamping mechanism 9 to realize the assembly of the one-dimensional centering mode. Two third threaded holes 205 are symmetrically provided on both sides of the second threaded hole 204. The axis of the third threaded hole 205 is parallel to the axis of the motor connector 2, and is used to connect the two fixed plates 4 to realize the assembly of the two-dimensional centering mode.

[0069] The first locking bolt 3 passes through the first threaded hole 203 defined in the hollow section 201 and is threadedly connected, with the end of the first locking bolt 3 abutting against the motor shaft 1. Thus, based on the interference fit between the motor connector 2 and the motor shaft 1, the first locking bolt 3 further ensures the reliability of the coaxial connection between the two.

[0070] The solid section 202 of the motor connector 2 can be connected to the rotating connector 8 through two fixed plates 4 and a stud shaft 5 to achieve assembly in a two-dimensional centering mode; it can also be directly connected to the laser clamping mechanism 9 to achieve assembly in a one-dimensional centering mode.

[0071] like Figure 4 and Figure 5 As shown, the fixing plate 4 includes a plate body 401 and a connecting post 402 connected to one end of the plate body 401. The connecting post 402 is provided with an external thread for mating with the third threaded hole 205 of the motor connector 2 for threaded connection. The plate body 401 defines a circular through-hole 403 for passing the end of the stud shaft 5. A key structure 404 is provided inside the circular through-hole 403. This key structure 404 is designed to mate with a keyway 503 of the stud shaft 5 to prevent relative rotation between the stud shaft 5 and the fixing plate 4.

[0072] like Figure 6 As shown, the main body of the stud shaft 5 is a solid cylindrical structure with a central axis 501 and external threads 502 at both ends for threaded connection with the hand nut 6. Furthermore, the stud shaft 5 is provided with a full-length keyway 503 extending axially for mating with the key structure 404 of the fixing plate 4.

[0073] like Figure 7 As shown, the main body of the rotating connector 8 is a hollow cylindrical structure. One end is provided with an internal thread 801 for threaded connection with the laser instrument clamping mechanism 9 in two-dimensional alignment mode, thereby achieving coaxial connection between the rotating connector 8 and the laser instrument clamping mechanism 9. The other end is provided with a radial through hole 802 and two fourth threaded holes 803. The axis of the radial through hole 802 is arranged radially along the rotating connector 8. The radial through hole 802 is used to pass through the stud shaft 5, and the rotating connector 8 can rotate around the stud shaft 5. The two fourth threaded holes 803 are respectively provided on either side of the radial through hole 802 for receiving the second locking bolt 7. The axis of the fourth threaded hole 803 is arranged radially along the rotating connector 8 and is preferably perpendicular to the axis of the radial through hole 802. The two fourth threaded holes 803 are arranged at an angle of 180°.

[0074] After the rotating connector 8 is rotated to a suitable position around the stud shaft 5, tightening the second locking bolts 7 can fix the rotating connector 8 to the stud shaft 5. The two second locking bolts 7 pass through the fourth threaded holes 803 and are threadedly connected thereto, with their ends abutting against the stud shaft 5 to clamp the stud shaft 5.

[0075] The stud shaft 5 passes through the radial through-hole 802 of the rotating connector 8 and the fixed plates 4 at either end. The key structure of the fixed plates 4 engages with the full-length keyway 503 of the stud shaft 5, restricting its rotation. Thumb nuts 6 are mounted on the outer sides of the two fixed plates 4, threadedly engaging the external threads 502 at either end of the stud shaft 5. During commissioning of the two-dimensional alignment device, adjusting the tightness of the two thumb nuts 6 effectively adjusts the coaxial connection between the rotating connector 8 and the motor connector 2.

[0076] The laser instrument clamping mechanism 9 can be threadedly connected to the rotating connector 8 to realize assembly in a two-dimensional centering mode; it can also be threadedly connected to the motor connector 2 to realize assembly in a one-dimensional centering mode.

[0077] like Figure 8 As shown, the laser instrument clamping mechanism 9 is a hollow cylindrical structure, comprising a connecting portion 901 and a clamping portion 902. The connecting portion 901 is provided with external threads for mating with the internal threads 801 of the rotating connector 8 or the second threaded hole 204 of the motor connector 2, thereby achieving a coaxial connection between the laser instrument clamping mechanism 9 and the rotating connector 8 or the motor connector 2. The clamping portion 902 is provided with a notch, which allows the inner diameter of the clamping portion 902 to expand and retract, thereby clamping the laser instrument 10.

[0078] The rear end of the laser instrument 10 is inserted into the clamping portion 902 of the laser instrument clamping mechanism 9. Due to the presence of the notch, the laser instrument clamping mechanism 9 can clamp the laser instrument 10. Two fixing buckles 11 are sheathed on the outside of the clamping portion 902. By adjusting the tightness of the two fixing buckles 11, the laser instrument 10 can be adjusted to be coaxially connected to the laser instrument clamping mechanism 9. The above connection enables the laser instrument clamping mechanism 9 to drive the laser instrument 10 to rotate around the axis of the motor shaft 1. In addition, the power supply line of the laser instrument 10 can also pass through the notch of the clamping portion 902 to prevent the presence of the power supply line from affecting the coaxiality of the laser instrument 10 and the laser instrument clamping mechanism 9.

[0079] The laser light emitted by the laser instrument 10 of the present invention is coaxial with the laser instrument 10. The laser instrument 10 is a mature device in the prior art, and a cylindrical laser of suitable size can be purchased directly from the market. For example, the KYD650N5 red point laser produced by Shenzhen Xinkunyang Technology Co., Ltd. can be used. The fixing clip 11 of this embodiment uses the Murray KLSS series throat clamp, but the present invention can use any throat clamp of suitable size and having the same function.

[0080] The laser emitted by the laser instrument 10 can be received by the laser receiving target 12 installed on the other motor shaft 1. The laser receiving target 12 can identify the position of the laser point formed by the laser on the laser receiving target 12 and output it as a coordinate value (X n ,Y n ) is used for error analysis.

[0081] The laser receiving target 12 and the motor shaft 1 are fitted with an interference fit to ensure coaxiality. Figure 9 As shown, a coordinate grid is provided on the laser receiving target 12 to facilitate the coordinate collection of the laser point.

[0082] like Figure 10 As shown, the in-situ biaxial testing machine alignment device is installed behind the motor shaft 1. Laser instrument 10 emits laser light, and laser receiver 12 identifies the laser point position. By rotating the laser instrument clamping mechanism 9 twice, three actual output positions (X1, Y1), (X2, Y2), and (X3, Y3) are acquired. The rotation range of the laser instrument clamping mechanism 9 is generally within 90°, which does not affect coaxiality.

[0083] The actual center of the laser receiving area (X0, Y0) and the three actual output positions (X1, Y1), (X2, Y2), and (X3, Y3) satisfy the following relationship:

[0084] (X1-X0) 2 +(Y1-Y0) 2 =(X2-X0) 2 +(Y2-Y0) 2 =(X3-X0) 2 +(Y3-Y0) 2

[0085] After determining the actual center (X0, Y0) of the laser receivable area, the actual diameter D of the laser receivable area can be calculated:

[0086]

[0087] Standard diameter D of the laser receiving area s With the standard center (X0 s ,Y0 s) are 0 and (0,0) respectively (calibrated on the laser receiving target 12), and the allowable error is 0.5mm.

[0088] Using the above-mentioned in-situ biaxial testing machine alignment method, proceed as follows:

[0089] For ease of description, in the centering method, the four motor shafts 1 of the biaxial testing machine are defined in the clockwise or counterclockwise direction as: the first motor shaft 1, the second motor shaft 1, the third motor shaft 1, and the fourth motor shaft 1. With the first motor shaft 1 as a reference, the other three motor shafts 1 are adjusted to achieve centering installation. Those skilled in the art will appreciate that when the present invention is actually used, the first motor shaft 1 can be any one of the four motor shafts 1 of the biaxial testing machine and is not limited to a specific orientation of up, down, left, right, or front, back, left, or right.

[0090] (1) Align the centering device according to Figure 2 The one-dimensional alignment mode shown is installed on the first motor shaft 1 , and the laser receiving target 12 is installed on the third motor shaft 1 , and the third motor shaft 1 is opposite to the first motor shaft 1 .

[0091] (2) Rotate the laser instrument clamping mechanism 9 so that it drives the laser instrument 10 to rotate twice around the motor connector 2, and collect the laser point positions (X1, Y1), (X2, Y2), and (X3, Y3) three times on the laser receiving target 12 to obtain the actual center (X0, Y0) and actual diameter D of the laser receivable area.

[0092] (3) Determine whether the actual diameter D of the laser receivable area is within the allowable error range; if not, proceed to step (4); if so, the laser emitted by the laser instrument 10 installed on the first motor shaft 1 is collinear with the axis of the first motor shaft 1, and proceed to step (5).

[0093] (4) After adjusting the tightness of the two fixing buckles 11, repeat steps (2) and (3).

[0094] (5) At this time, the centering device of the one-dimensional centering mode is debugged and step (2) is repeated; it is determined whether the actual center (X0, Y0) and the actual diameter D of the laser receivable area are within the allowable error range; if not, step (6) is performed; if so, the axis of the third motor shaft 1 is collinear with the axis of the first motor shaft 1, and step (7) is performed.

[0095] (6) After adjusting the installation position of the third motor shaft 1, repeat step (5).

[0096] (7) At this point, the alignment and installation of the third motor shaft 1 is completed.

[0097] The centering device is Figure 2The one-dimensional alignment mode shown is adjusted to Figure 1 The two-dimensional alignment mode shown is mounted on the first motor shaft 1 , and the laser receiving target 12 is still mounted on the third motor shaft 1 .

[0098] (8) Rotate the laser instrument clamping mechanism 9 so that it drives the laser instrument 10 to rotate twice around the rotating connector 8, and collect the laser point positions (X1, Y1), (X2, Y2), and (X3, Y3) three times on the laser receiving target 12 to obtain the actual center (X0, Y0) and actual diameter D of the laser receivable area.

[0099] (9) Determine whether the actual diameter D of the laser receivable area is within the allowable error range; if not, proceed to step (10); if so, the axes of the laser instrument clamping mechanism 9 and the rotating connecting member 8 are collinear, and proceed to step (11).

[0100] (10) After adjusting the tightness of the two fixing buckles 11, repeat steps (8) and (9).

[0101] (11) Determine whether the actual center (X0, Y0) of the laser receivable area is within the allowable error range; if not, proceed to step (12); if so, the laser emitted by the laser instrument 10 installed on the first motor shaft 1 is collinear with the axis of the first motor shaft 1, and proceed to step (13).

[0102] (12) After adjusting the tightness of the two hand nuts 6, repeat step (11).

[0103] (13) At this point, the centering device debugging of the two-dimensional centering mode is completed.

[0104] Install the laser receiving target 12 on the second motor shaft 1, loosen the second locking bolt 7, rotate the rotating connector 8 around the stud shaft 5 until the laser emitted by the laser instrument 10 is directed toward the laser receiving target 12 and as close to the center of the laser receiving target 12 as possible, and then tighten the second locking bolt 7.

[0105] (14) Repeat step (8) and determine whether the actual center (X0, Y0) and actual diameter D of the laser receivable area are within the allowable error range; if not, proceed to step (15); if so, the coplanar installation of the second motor shaft 1 is completed, and proceed to step (16).

[0106] (15) After adjusting the installation position of the second motor shaft 1, repeat step (14).

[0107] (16) Install the laser receiving target 12 on the fourth motor shaft 1, loosen the second locking bolt 7, rotate the rotating connector 8 around the stud shaft 5 until the laser emitted by the laser instrument 10 is directed toward the laser receiving target 12 and as close to the center of the laser receiving target 12 as possible, and then tighten the second locking bolt 7.

[0108] (17) Repeat step (8) and determine whether the actual center (X0, Y0) and actual diameter D of the laser receivable area are within the allowable error range; if not, proceed to step (18); if so, the coplanar installation of the fourth motor shaft 1 is completed, and proceed to step (19).

[0109] (18) After adjusting the installation position of the fourth motor shaft 1, repeat step (17).

[0110] (19) At this time, the first motor shaft 1, the second motor shaft 1, the third motor shaft 1, and the fourth motor shaft 1 are coplanar, and the first motor shaft 1 and the third motor shaft 1 are coaxial.

[0111] The centering device is Figure 1 The two-dimensional alignment mode shown is adjusted to Figure 2 The one-dimensional alignment mode shown is mounted on the second motor shaft 1 , and the laser receiving target 12 is still mounted on the fourth motor shaft 1 .

[0112] (20) Repeat step (2) and determine whether the actual diameter D of the laser receivable area is within the allowable error range; if not, proceed to step (21); if so, the laser emitted by the laser instrument 10 installed on the second motor shaft 1 is collinear with the axis of the second motor shaft 1, and proceed to step (22).

[0113] (21) After adjusting the tightness of the two fixing buckles 11, repeat step (20).

[0114] (22) At this point, the centering device of the one-dimensional centering mode is debugged and step (2) is repeated; determine whether the actual center (X0, Y0) and actual diameter D of the laser-receivable area are within the error tolerance range; if not, proceed to step (23); if so, the axes of the fourth motor shaft 1 and the second motor shaft 1 are collinear, and the centering installation of the fourth motor shaft 1 and the second motor shaft 1 is complete. At this point, the first motor shaft 1, the second motor shaft 1, the third motor shaft 1, and the fourth motor shaft 1 are coplanar, and the first motor shaft 1 and the third motor shaft 1 are coaxial, and the second motor shaft 1 and the fourth motor shaft 1 are coaxial.

[0115] (23) After adjusting the installation position of the fourth motor shaft 1, repeat step (22); the adjustment of the installation position of the fourth motor shaft 1 in this step is limited to adjustment within the plane, which refers to the plane where the first motor shaft 1, the second motor shaft 1, the third motor shaft 1, and the fourth motor shaft 1 are coplanar.

[0116] Finally, the first motor shaft 1 , the second motor shaft 1 , the third motor shaft 1 , and the fourth motor shaft 1 are precisely located in the same installation plane, and the first motor shaft 1 and the third motor shaft 1 , the second motor shaft 1 and the fourth motor shaft 1 are precisely coaxial, completing the installation.

[0117] Although the preferred embodiments of the present invention have been described above in conjunction with the accompanying drawings, the present invention is not limited to the above-mentioned specific embodiments. The above-mentioned specific embodiments are merely illustrative and not restrictive. Under the guidance of the present invention, ordinary technicians in this field can also make many forms of specific changes without departing from the scope of protection of the invention and the claims. These all fall within the scope of protection of the present invention.

Claims

1. An in-situ biaxial testing machine centering device, characterized in that: It includes a motor connector, a laser instrument clamping mechanism, a laser instrument, a fixed plate, a stud bolt rotating shaft, and a rotating connector; the motor connector, the laser instrument clamping mechanism, and the laser instrument are connected to form a one-dimensional alignment mode for achieving coaxial installation of two relative motor shafts; the motor connector, the fixed plate, the stud bolt rotating shaft, the rotating connector, the laser instrument clamping mechanism, and the laser instrument are connected to form a two-dimensional alignment mode for achieving coplanar installation of four motor shafts; The motor connector is sleeved on the outside of the motor shaft and has an interference fit with the motor shaft, and the motor connector and the motor shaft are fixed by a first locking bolt to achieve coaxial connection between the motor connector and the motor shaft; The laser instrument clamping mechanism includes a connecting portion and a clamping portion, wherein the connecting portion is used to be threadedly connected to the motor connector or the rotating connector, and the clamping portion is used to clamp the laser instrument. The clamping portion is externally sleeved with two fixing buckles. By adjusting the tightness of the two fixing buckles, the laser instrument can be adjusted to be coaxially connected to the laser instrument clamping mechanism; The laser emitted by the laser instrument can be received by a laser receiving target installed on another motor shaft, and the laser receiving target is coaxially arranged with the motor shaft to which it is connected; the laser receiving target can identify the position of the laser point and output the coordinate value for error analysis; The rotating connection member is coaxially arranged with the laser instrument clamping mechanism, one end of which is used for threaded connection with the laser instrument clamping mechanism in a two-dimensional alignment mode, and the other end of which is used for passing the stud bolt shaft; the rotating connection member can rotate around the stud bolt shaft, and after being rotated into place, the rotating connection member and the stud bolt shaft are fixed by a second locking bolt; one end of the rotating connection member is provided with an internal thread, which is used to connect to the laser instrument clamping mechanism; the other end is provided with a radial through hole and two fourth threaded holes, the axis of the radial through hole is used to pass through the stud bolt shaft; the two fourth threaded holes are respectively provided on both sides of the radial through hole for mounting the second locking bolt; The stud bolt shaft passes through the rotating connector and the fixed plate, and both ends of the stud bolt shaft are respectively threadedly connected to the hand nuts; the middle part of the stud bolt shaft is a smooth axis for passing through the rotating connector and the fixed plate; both ends of the stud bolt shaft are provided with external threads for mounting the hand nuts; and the stud bolt shaft is provided with a full-length keyway extending in the axial direction for mating with the key structure provided on the fixed plate; The two fixing plates are respectively located between the two hand-tightening nuts and the rotating connecting piece, and are symmetrically arranged with the axis of the rotating connecting piece as the center line; the fixing plate is fixedly connected to the motor connecting piece and the stud bolt shaft; the fixing plate includes a plate body and a connecting column connected to one end of the plate body, the axis of the connecting column is parallel to the axis of the motor connecting piece; the connecting column is provided with an external thread for threaded connection with the motor connecting piece; the plate body is provided with a circular through hole, the circular through hole is used to allow the end of the stud bolt shaft to pass through; a key structure is provided on the inner side of the circular through hole, and the key structure is used to cooperate with the keyway of the stud bolt shaft; Thus, the motor connector is connected to the rotating connector through the two fixed plates and the stud bolt shaft, and the rotating connector is connected to the laser instrument through the laser instrument clamping mechanism, forming a two-dimensional alignment mode; the motor connector is directly connected to the laser instrument through the laser instrument clamping mechanism, forming a one-dimensional alignment mode.

2. The in-situ biaxial testing machine centering device according to claim 1, characterized in that: The motor connector is a cylinder, including a hollow section and a solid section that are integrally connected; the end face of the hollow section is open, and is used to be sleeved on the outside of the motor shaft and interference fit with the motor shaft; the side wall of the hollow section is provided with a first threaded hole, and the axis of the first threaded hole is arranged along the radial direction of the motor connector, for installing the first locking bolt; the end face of the solid section is provided with a second threaded hole and two third threaded holes, and the second threaded hole is coaxial with the motor connector, and is used to connect the laser clamping mechanism in a one-dimensional centering mode; the two third threaded holes are symmetrically arranged on both sides of the second threaded hole, and the axis of the third threaded hole is parallel to the axis of the motor connector, and are respectively used to connect the two fixed plates.

3. The in-situ biaxial testing machine centering device according to claim 1, characterized in that: The first locking bolt passes through the first threaded hole of the motor connector and is threadedly connected, and the end of the first locking bolt abuts against the motor shaft.

4. The in-situ biaxial testing machine centering device according to claim 1, characterized in that: The connecting part of the laser instrument clamping mechanism is provided with an external thread for threaded connection with the rotating connecting part or the motor connecting part; the clamping part of the laser instrument clamping mechanism is provided with a notch, through which the inner diameter of the clamping part can be expanded and retracted to achieve clamping of the laser instrument.

5. The in-situ biaxial testing machine centering device according to claim 1, characterized in that: The second locking bolt passes through the rotating connector and is threadedly connected to the rotating connector, and its end abuts against the stud bolt shaft; the axis of the second locking bolt is arranged along the radial direction of the rotating connector and is perpendicular to the axis of the radial through hole of the rotating connector; the two second locking bolts are arranged with an axis angle of 180°.

6. A method for calibrating an in-situ biaxial testing machine based on the centering device according to any one of claims 1 to 5, characterized in that: Taking any selected first motor shaft as a reference, adjust the second motor shaft, the third motor shaft, and the fourth motor shaft to achieve centering installation; wherein the first motor shaft is opposite to the third motor shaft, and the second motor shaft is opposite to the fourth motor shaft; The steps include: (1) Installing the centering device on the first motor shaft according to the one-dimensional centering mode, and installing the laser receiving target on the third motor shaft; (2) Rotate the laser instrument clamping mechanism so that it drives the laser instrument to rotate twice around the motor connector, collect the laser point position three times on the laser receiving target, and obtain the actual center of the laser receiving area and actual diameter ; (3) Determine the actual diameter of the laser-receivable area Is it within the allowable error range? If not, proceed to step (4); if so, the laser instrument mounted on the first motor shaft is coaxial with the first motor shaft, proceed to step (5); (4) After adjusting the tightness of the two fixing buckles, repeat steps (2) and (3); (5) At this time, the one-dimensional centering mode centering device debugging is completed, and step (2) is repeated; the actual center of the laser receiving area is determined. and actual diameter Is it within the allowable error range? If not, proceed to step (6); if so, the third motor shaft is coaxial with the first motor shaft 1, proceed to step (7); (6) After adjusting the installation position of the third motor shaft, repeat step (5); (7) At this time, the alignment installation of the third motor shaft is completed, and the alignment device is adjusted from the one-dimensional alignment mode to the two-dimensional alignment mode and installed on the first motor shaft; (8) Rotate the laser instrument clamping mechanism so that it drives the laser instrument to rotate twice around the rotating connector, collect the laser point position three times on the laser receiving target, and obtain the actual center of the laser receiving area and actual diameter ; (9) Determine the actual diameter of the laser-receivable area Is it within the allowable error range? If not, proceed to step (10); if so, the laser instrument clamping mechanism and the rotating connecting member are coaxial, proceed to step (11); (10) After adjusting the tightness of the two fixing buckles, repeat steps (8) and (9); (11) Determine the actual center of the laser receiving area Is it within the allowable error range? If not, proceed to step (12); if so, the laser instrument installed on the first motor shaft is coaxial with the first motor shaft, proceed to step (13); (12) After adjusting the tightness of the two hand nuts, repeat step (11); (13) At this time, the centering device of the two-dimensional centering mode is debugged, the laser receiving target is installed on the second motor shaft, the second locking bolt is loosened, and the rotating connector is rotated around the stud bolt shaft until the laser emitted by the laser instrument is directed toward the laser receiving target and as close to the center of the laser receiving target as possible, and then the second locking bolt is tightened; (14) Repeat step (8) and determine the actual center of the laser receiving area. and actual diameter Is it within the allowable error range? If not, proceed to step (15); if so, the coplanar installation of the second motor shaft is completed, proceed to step (16); (15) After adjusting the installation position of the second motor shaft, repeat step (14); (16) Install the laser receiving target on the fourth motor shaft, loosen the second locking bolt, rotate the rotating connector around the stud shaft until the laser emitted by the laser instrument is directed toward the laser receiving target and as close to the center of the laser receiving target as possible, and then tighten the second locking bolt; (17) Repeat step (8) and determine the actual center of the laser receiving area. and actual diameter Is it within the allowable error range? If not, proceed to step (18); if so, the fourth motor shaft is coplanarly installed and proceed to step (19); (18) After adjusting the installation position of the fourth motor shaft, repeat step (17); (19) At this time, the first motor shaft, the second motor shaft, the third motor shaft, and the fourth motor shaft are coplanar, and the first motor shaft and the third motor shaft are coaxial; the centering device is adjusted from a two-dimensional centering mode to a one-dimensional centering mode, and is installed on the second motor shaft; (20) Repeat step (2) and determine the actual diameter of the laser-receivable area. Is it within the allowable error range? If not, proceed to step (21); if so, the laser instrument installed on the second motor shaft is coaxial with the second motor shaft, proceed to step (22); (21) After adjusting the tightness of the two fixing buckles, repeat step (20); (22) At this point, the one-dimensional centering mode centering device is debugged and step (2) is repeated; the actual center of the laser receiving area is determined. and actual diameter Is it within the allowable error range? If not, proceed to step (23); if so, the fourth motor shaft is coaxial with the second motor shaft. At this point, the first motor shaft, the second motor shaft, the third motor shaft, and the fourth motor shaft are in the same installation plane, and the first motor shaft and the third motor shaft, the second motor shaft and the fourth motor shaft are coaxial, and the installation is completed. (23) After adjusting the installation position of the fourth motor shaft, repeat step (22); The adjustment of the installation position of the fourth motor shaft in this step is limited to adjustment within the plane, which refers to the plane where the first motor shaft, the second motor shaft, the third motor shaft, and the fourth motor shaft are coplanar.

7. The in-situ biaxial testing machine calibration method according to claim 6, characterized in that: Rotate the laser instrument clamping mechanism twice and collect three laser point positions on the laser receiving target. 、 、 ;The actual center of the laser receiving area With three actual output positions 、 、 The following relations are satisfied: ； And, according to the actual center of the laser receiving area Calculate the actual diameter of the laser-receivable area : ； Standard center of the laser receiving area The corresponding coordinates on the laser receiving target are , standard diameter 0; passes through the actual center of the laser receiving area With the standard center Comparison and actual diameter With standard diameter Compare and conduct error analysis.

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