CN112729818B - Testing device and method for torsional vibration modal test of gear box - Google Patents
Testing device and method for torsional vibration modal test of gear box Download PDFInfo
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- CN112729818B CN112729818B CN202110158249.5A CN202110158249A CN112729818B CN 112729818 B CN112729818 B CN 112729818B CN 202110158249 A CN202110158249 A CN 202110158249A CN 112729818 B CN112729818 B CN 112729818B
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/02—Gearings; Transmission mechanisms
- G01M13/021—Gearings
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M13/00—Testing of machine parts
- G01M13/02—Gearings; Transmission mechanisms
- G01M13/028—Acoustic or vibration analysis
Abstract
The invention discloses a testing device and a testing method for a torsional vibration modal test of a gear box, belonging to the technical field of structural dynamics vibration tests, and the device comprises: the device comprises a bottom plate, a gear box, a speed reducer plate, an input shaft sleeve, an output shaft sleeve, two mounting plates, an L-shaped support, a T-shaped support, a square rod, four spring hooks, two lifting ring screws, two springs, three acceleration sensors, a force sensor and an ICP type force hammer; the device enables the gear box to be in a torsional state by pre-tightening two springs, oscillography sampling is carried out by adopting a signal triggering sampling mode, an ICP type force hammer is used for hammering the shell of the gear box in parallel to give an excitation signal to a measuring device, a multi-channel vibration meter is used for collecting a response signal of a sensor, and a computer is used for recording; the invention can measure the torsional vibration of the gear box and obtain the inherent characteristics and the vibration response of the gear box during the torsional vibration.
Description
Technical Field
The invention belongs to the technical field of structural dynamics vibration testing, and particularly relates to a testing device and method for a torsional vibration modal test of a gear box.
Background
The torsional vibration is the main form of vibration of the gear, and therefore, the problem caused by the torsional vibration is considered when the gear is actually operated. The inherent nature of the torsional vibration of a gear system depends on the stiffness and moment of inertia of all the shafts, gears, and the like of the system. Furthermore, for a complex gear system, many inherent modes of vibration may occur within its rotational speed. When the frequency of the applied torque causing the gear system to twist is equal to or close to the natural frequency of the gear system twist, resonances can occur that severely disrupt system operation or completely fail. Research shows that under the condition of severe resonance, torque is reversed, so that internal gear teeth in the gear system are disengaged, and faults and noises are generated. At present, a device and a method for testing a vibration mode of a gearbox are basically based on free vibration of a gear system, a three-point hammering method is selected, and the method is not suitable for testing the mode of torsional vibration.
Disclosure of Invention
In view of the above, the present invention provides a device and a method for testing a torsional vibration mode of a gearbox, which can obtain the inherent characteristics and the vibration response of the gearbox during torsional vibration.
The invention is realized by the following technical scheme:
a test device for a torsional vibration modal test of a gear box comprises an input end tangential force and motion measuring device, an output end tangential force and motion measuring device, a gear box shell measuring device, an excitation device, a signal acquisition and analysis device and the gear box for testing;
the input tangential force and motion measurement apparatus comprises: the input shaft comprises an input shaft sleeve, an input end spring hook, a force sensor, two lifting eye screws, an input end spring, an L-shaped support, an input end mounting plate and an input end acceleration sensor;
the output tangential force and motion measuring device comprises: the output end acceleration sensor, the square rod, the output end spring hook, the output end spring, the T-shaped support, the output end mounting plate and the output shaft sleeve are arranged on the output end;
the vibration excitation device is an ICP type force hammer;
the gearbox shell measuring device is a shell acceleration sensor;
the input end spring and the force sensor are connected in series through two lifting ring screws and two input end spring hooks, and the two input end spring hooks are respectively arranged on the input shaft sleeve and the L-shaped bracket;
the output end spring is arranged at the output end of the gear box through two output end spring hooks, and the two output end spring hooks are respectively arranged on the square rod and the T-shaped bracket;
the overall connection relationship is as follows: the gear box is arranged on the speed reducer plate, and the speed reducer plate is fixed in the middle of the bottom plate; the input shaft sleeve and the output shaft sleeve are respectively arranged on an input shaft and an output shaft of the gear box; the square rod is arranged in a cylindrical hole of the output shaft sleeve through a screw; the input end mounting plate and the output end mounting plate are respectively mounted on the bottom plate, and the L-shaped bracket and the T-shaped bracket are respectively mounted on the input end mounting plate and the output end mounting plate and are fixed through screws; the input end spring, the force sensor are connected in series through two lifting ring screws and two input end spring hooks, and the two input end spring hooks are respectively arranged on the input shaft sleeve and the L-shaped bracket; the output end spring is arranged at the output end of the gear box through two output end spring hooks, and the two output end spring hooks are respectively arranged on the square rod and the T-shaped bracket;
the three acceleration sensors are respectively arranged on the input shaft sleeve, the square rod and the gear box shell, are parallel to the tangential direction of each shaft of the gear box and are used for measuring vibration response signals;
the ICP type force hammer is used for giving a hammering exciting signal to the gearbox, and the hammering direction is parallel to the measured acceleration direction of the shell acceleration sensor.
Furthermore, the force sensor adopts a bidirectional tension and compression piezoelectric sensor, and the acceleration sensor adopts a piezoelectric acceleration sensor.
Furthermore, the positions of the input end spring and the output end spring after being pre-tightened are parallel to the horizontal plane.
Further, the input end spring is positioned between the input shaft and the output shaft of the gear box.
A test method for a torsional vibration modal test of a gearbox is based on the device and comprises the following steps:
firstly, connecting a force sensor, an acceleration sensor and an ICP type force hammer in the device with a multi-channel vibration meter, and connecting the multi-channel vibration meter with a computer;
secondly, oscillography sampling is carried out in a signal triggering sampling mode, an ICP type force hammer is used for hammering the shell of the gear box in parallel to give an excitation signal to a measuring device, a multi-channel vibration meter is used for collecting a response signal of a sensor, and a computer is used for recording;
and thirdly, performing frequency spectrum analysis according to the data of the three acceleration sensors, the force sensor and the ICP type force hammer signals obtained in the second step, and extracting the natural frequency, the phase and the coherence coefficient of the torsional vibration of the gearbox.
Has the advantages that: the invention provides a testing device and a testing method for a torsional vibration modal test of a gear box, which adopt signal triggering to ensure that each channel of a sensor meets sampling conditions after reaching a trigger level, can accurately measure acceleration response signals of an input shaft, an output shaft and a shell of the gear box, and obtain the inherent characteristics of the gear box during torsional vibration.
Drawings
FIG. 1 is a schematic structural composition of the present invention;
FIG. 2 is a schematic view of an input shaft sleeve of the present invention;
FIG. 3 is a schematic view of an output shaft sleeve;
FIG. 4 is a schematic view of a square bar;
FIG. 5 is a schematic view of an input mounting plate;
FIG. 6 is a schematic view of an output mounting plate;
FIG. 7 is a schematic view of an output end snap hook;
FIG. 8 is the results of self-spectroscopic analysis of three accelerations;
FIG. 9 is a hammer input force self-spectral analysis of test number 2;
FIG. 10 is a transfer function of hammer input force versus input shaft acceleration vibration response for test number 2;
FIG. 11 is a transfer function of hammer input force versus output shaft acceleration vibration response for test number 2;
wherein, 1-a bottom plate; 2-a retarder plate; 3-a gearbox; 4-an input shaft sleeve; 5-input end spring hook; 6-a force sensor; 7-a lifting eye screw; 8-input end spring; a 9-L shaped scaffold; 10-an output end acceleration sensor; 11-square bar; 12-output end spring hook; 13-output end spring; 14-a nut; 15-T-shaped stents; 16-a screw; 17-an output end mounting plate; an 18-ICP type force hammer; 19-housing acceleration sensor; 20-an output shaft sleeve; 21-input mounting plate; 22-input acceleration sensor;
Detailed Description
The invention is described in detail below by way of example with reference to the accompanying drawings.
Example 1:
the embodiment provides a test device for a torsional vibration mode test of a gearbox, referring to fig. 1, comprising: the device comprises a bottom plate 1, a speed reducer plate 2, a gear box 3, an input shaft sleeve 4, an input end spring hook 5, a force sensor 6, two lifting eye screws 7, an input end spring 8, an L-shaped support 9, an output end acceleration sensor 10, a square rod 11, an output end spring hook 12, an output end spring 13, a nut 14, a T-shaped support 15, a screw 16, an output end mounting plate 17, an ICP type force hammer 18, a gear box shell acceleration sensor 19, an output shaft sleeve 20, an input end mounting plate 21 and an input end acceleration sensor 22, wherein the gear box to be measured is 3 in the embodiment;
the force sensor 6 adopts a bidirectional tension-compression piezoelectric type sensor, and the output end acceleration sensor 10, the shell acceleration sensor 19 and the input end acceleration sensor 22 adopt piezoelectric type acceleration sensors;
referring to fig. 2, the ear of the input shaft sleeve 4 is provided with a through hole for mounting the spring hook 5;
referring to fig. 3, a cylindrical hole is formed in an ear of the output shaft sleeve 20 for mounting the square rod 11;
referring to fig. 4, the square rod 11 is provided with a through hole and a threaded hole for respectively matching with the output shaft sleeve 20 and installing the spring hook 12 and the acceleration sensor 10;
referring to fig. 5, the input end mounting plate 21 is installed between the input shaft and the output shaft of the gear box 3, and is T-shaped in structure, and a rectangular weight reduction groove is formed in the middle;
referring to fig. 6, the output end mounting plate 17 is a T-shaped structure, a rectangular weight reduction groove is formed in the middle, and a rectangular groove is formed in the upper surface of the output end mounting plate and used for mounting the T-shaped bracket 15;
referring to fig. 6, the output end spring hook 12 is composed of a bolt part and a fixing hook;
the overall connection relationship is as follows: the gear box 3 is arranged on the speed reducer plate 2, and the speed reducer plate 2 is fixed in the middle of the bottom plate 1; the input shaft sleeve 4 and the output shaft sleeve 20 are respectively arranged on the input shaft and the output shaft of the gear box; the square rod 11 is arranged in a cylindrical hole of the output shaft sleeve 20 through a screw; the input end mounting plate 21 and the output end mounting plate 17 are respectively mounted on the bottom plate 1, and the L-shaped bracket 9 and the T-shaped bracket 15 are respectively mounted on the input end mounting plate 21 and the output end mounting plate 17 and fixed through screws; the input end spring 8 and the force sensor 6 are connected in series through two lifting ring screws 7 and two input end spring hooks 5, and the two input end spring hooks 5 are respectively arranged on the input shaft sleeve 4 and the L-shaped bracket 9; the output end spring 13 is arranged at the output end of the gear box 3 through two output end spring hooks 12, and the two output end spring hooks 12 are respectively arranged on the square rod 11 and the T-shaped bracket 15; the two springs are parallel to the ground;
the input end acceleration sensor 22 and the gearbox 3 shell acceleration sensor 19 are respectively arranged on the input shaft sleeve 4 ear and the gearbox 3 shell through magnetic suction seats, the other output end acceleration sensor 10 is arranged on the square rod 11 through screws, and the three acceleration sensors are used for measuring vibration response signals under excitation signals.
Example 2:
the embodiment provides a test method for a torsional vibration mode test of a gearbox based on the device in the embodiment 1, and the method comprises the following steps:
the first step, the device of example 1 is assembled, wherein the nut is tightened by a wrench to place the spring in a pre-tensioned state;
secondly, connecting a sensor in the device in the first step into a multi-channel vibration meter, wherein the multi-channel vibration meter is connected with a computer;
thirdly, oscillography sampling is carried out in a signal triggering sampling mode, an ICP type force hammer is used for hammering the shell of the gear box in parallel to give an excitation signal to a measuring device, a multi-channel vibration meter is used for collecting a response signal of a sensor, and a computer is used for recording the response signal;
fourthly, performing spectrum analysis according to the data of the signals of the three acceleration sensors, the force sensor and the ICP type force hammer sensor obtained in the third step, and extracting the natural frequency, the phase and the coherence coefficient of the torsional vibration of the gearbox, wherein the processing result is as follows:
from the 15 repeatability tests performed, three spectra of accelerations were obtained, see fig. 8, from which the first 6 modes were found;
performing transfer function FRF analysis on the test result, taking a test number 2 as an example, referring to FIG. 9, as a self-spectrum analysis result of the hammering input force, the hammering input force is attenuated to be the lowest at 3KHz, the peak value of the transfer function in the test number 2 appears at 3037.5Hz, and the coherence coefficient of the input force signal and the acceleration vibration signal is only 0.66, which indicates that the hammering input force signal excites a certain order natural frequency of torsional vibration of the gear system in the attenuation process, wherein the natural frequency is not influenced by forced vibration and belongs to the natural frequency of the system, and the frequency is close to a 3-order mode through analysis;
referring to fig. 10, a transfer function of a hammer input force versus input shaft acceleration vibration response is shown;
referring to fig. 11, the transfer function of the hammer input force versus output shaft acceleration vibration response is shown;
in summary, the above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. A test device for a torsional vibration modal test of a gear box is characterized by comprising an input end tangential force and motion measuring device, an output end tangential force and motion measuring device, a gear box shell measuring device, an excitation device, a signal acquisition and analysis device and the gear box for testing;
the input tangential force and motion measurement apparatus comprises: the device comprises an input shaft sleeve (4), an input end spring hook (5), a force sensor (6), two lifting eye screws (7), an input end spring (8), an L-shaped support (9), an input end mounting plate (21) and an input end acceleration sensor (22);
the output tangential force and motion measuring device comprises: the device comprises an output end acceleration sensor (10), a square rod (11), an output end spring hook (12), an output end spring (13), a T-shaped support (15), an output end mounting plate (17) and an output shaft sleeve (20);
the vibration excitation device is an ICP type force hammer (18);
the gearbox shell measuring device is a shell acceleration sensor (19);
the overall connection relationship is as follows: the gear box (3) is arranged on the speed reducer plate (2), and the speed reducer plate (2) is fixed in the middle of the bottom plate (1); the input shaft sleeve (4) and the output shaft sleeve (20) are respectively arranged on an input shaft and an output shaft of the gear box (3); the square rod (11) is arranged in a cylindrical hole of the output shaft sleeve (20) through a screw; an input end mounting plate (21) and an output end mounting plate (17) are respectively mounted on the bottom plate (1), and an L-shaped bracket (9) and a T-shaped bracket (15) are respectively mounted on the input end mounting plate (21) and the output end mounting plate (17) and fixed through screws (16); the input end spring (8) and the force sensor (6) are connected in series through two lifting eye screws (7) and two input end spring hooks (5), and the two input end spring hooks (5) are respectively arranged on the input shaft sleeve (4) and the L-shaped bracket (9); an output end spring (13) is arranged at the output end of the gear box (3) through two output end spring hooks (12), and the two output end spring hooks (12) are respectively arranged on the square rod (11) and the T-shaped bracket (15);
the input end acceleration sensor (22), the output end acceleration sensor (10) and the shell acceleration sensor (19) are respectively arranged on the input shaft sleeve (4), the square rod (11) and the shell of the gear box (3), are parallel to the tangential direction of each shaft of the gear box (3) and are used for measuring vibration response signals;
the ICP type force hammer (18) is used for giving a hammering exciting signal to the gear box (3), and the hammering direction is parallel to the measuring acceleration direction of the shell acceleration sensor (19).
2. The testing device for the torsional vibration mode test of the gearbox as defined in claim 1, wherein the force sensor (6) is a bidirectional tension and compression piezoelectric type sensor, and the output end acceleration sensor (10), the shell acceleration sensor (19) and the input end acceleration sensor (22) are piezoelectric type acceleration sensors.
3. The test device for the torsional vibration mode test of the gearbox as claimed in claim 1, characterized in that the pre-tensioned positions of the input end spring (8) and the output end spring (13) are parallel to the horizontal plane.
4. A gearbox torsional vibration mode test testing arrangement as defined in claim 1, characterized in that said input end spring (8) is located between the input shaft and the output shaft of the gearbox (3).
5. A test method for a torsional vibration mode test of a gearbox is based on the test device for the torsional vibration mode test of the gearbox of claim 1, and is characterized by comprising the following steps:
firstly, connecting a force sensor (6), an output end acceleration sensor (10), a shell acceleration sensor (19), an input end acceleration sensor (22) and an ICP type force hammer (18) in the gearbox torsional vibration modal test testing device with a multi-channel vibration meter, wherein the multi-channel vibration meter is connected with a computer;
secondly, oscillography sampling is carried out in a signal triggering sampling mode, an ICP type force hammer (18) is used for hammering the shell of the gear box (3) in parallel to give an excitation signal to a measuring device, a multichannel vibration meter is used for collecting a response signal of a sensor, and a computer is used for recording;
and thirdly, performing frequency spectrum analysis according to the data of the response signals of the output end acceleration sensor (10), the shell acceleration sensor (19), the input end acceleration sensor (22), the force sensor (6) and the ICP type force hammer (18) obtained in the second step, and extracting the natural frequency, the phase and the coherence coefficient of the torsional vibration of the gearbox.
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| CN202110158249.5A CN112729818B (en) | 2021-02-04 | 2021-02-04 | Testing device and method for torsional vibration modal test of gear box |
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| CN114152436A (en) * | 2021-11-22 | 2022-03-08 | 中南大学 | Gear shaft modal test testing device and method under constraint condition |
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