CN110779991A

CN110779991A - Porous material sound absorption and insulation test method and adjustable deflection test device thereof

Info

Publication number: CN110779991A
Application number: CN201910876729.8A
Authority: CN
Inventors: 黄丹; 原房彤; 李卓; 赵武; 赵钊; 刘旭豪
Original assignee: Henan University of Technology
Current assignee: Henan University of Technology
Priority date: 2019-09-17
Filing date: 2019-09-17
Publication date: 2020-02-11
Anticipated expiration: 2039-09-17
Also published as: CN110779991B

Abstract

The invention discloses a sound absorption and insulation test method for porous materials and an adjustable deflection test device thereof, wherein the device comprises a lifting moving unit, a cavity unit and an adjustable deflection test unit; the lifting moving unit consists of an electric cylinder and a linear motor, the electric cylinder and the linear motor ensure the close fit of an upper cavity and a lower cavity, and six test boards form a test cabin for placing porous material samples; the cavity body consists of an upper cavity body and a lower cavity body and forms a closed cavity; the adjustable deflection test unit comprises a transposition module, an upper test module and an adjustable lower test module, and can meet the requirement of multi-surface sound absorption and sound insulation performance test of the porous material sample. The test method is to use the device to completely test the sound absorption and insulation performance of the porous material in sequence, the invention has simple operation, the size of the porous material sample can be adjusted, two test methods are provided, the test efficiency is high, the test result is accurate, the manual operation in the test process is not needed, and the automatic integrated control is realized.

Description

Porous material sound absorption and insulation test method and adjustable deflection test device thereof

Technical Field

The invention relates to the technical field of porous material experimental tests, in particular to a sound absorption and insulation test method for a porous material and an adjustable deflection test device thereof.

Background

An excellent sound insulation and absorption material in porous materials is widely used in devices with special requirements on sound insulation and absorption in the environmental protection field, but the testing device of the porous materials is quite monotonous, few and few. The existing sound absorption and insulation performance test of the material mainly comprises two modes, one mode is a test mode through a standing wave tube, the test principle of the standing wave tube is that standing waves are formed in the tube through the direction and phase difference of incident waves and reflected waves formed by the reflection of the surface of the material, and the sound absorption coefficient of the material is determined through the sound level difference of maximum sound pressure and minimum sound pressure; and the other method is to test through an impedance tube, wherein the impedance tube test principle is to measure sound pressure at two positions close to a sample, obtain the sound transfer function of two microphone signals, and calculate the normal incidence complex reflection factor, the normal incidence sound absorption coefficient and the sound impedance rate of the sample through the function. The two testing methods both require that the shape of the sample is cylindrical, and require that the diameter of the material sample is fixed, and the thickness can be adjustable, if the shape specification and the dimension specification of the material are changed, the two methods can not complete the sound absorption and insulation performance test of the porous material.

On the other hand, for the performance of the porous material, the porous material is an internal porous structure which is specially designed, and the material performances shown in different directions are different, so that the measurement needs to be carried out in different directions.

Disclosure of Invention

The invention aims to provide a sound absorption and insulation test method for porous materials and an adjustable deflection test device thereof aiming at the defects of the prior art, so that the limitation of the existing sound absorption and insulation test device for porous materials is solved, the test time is reduced, and the experiment period is shortened.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

an adjustable deflection test device at least comprises an adjustable deflection test unit, wherein the adjustable deflection test unit at least comprises a test module; the test module comprises an upper test module and a lower test module which can be close to or far away and can be matched in an adjustable way; the upper test module is a liftable module, is far away from or close to the lower test module through lifting, and comprises a fourth test board, a fifth test board and a sixth test board which are mutually intersected to form a right angle, and the relative positions of the fourth test board, the fifth test board and the sixth test board are fixed to form a concave-upward semi-surrounding structure; the lower test module is a rotatable position-changing module and comprises a first test board, a second test board and a third test board which are mutually intersected to form a right angle, and the first test board, the second test board and the third test board can relatively move and form a concave semi-surrounding structure; one of the fourth test board, the fifth test board and the sixth test board is provided with a wave generator, and the other two test boards, the first test board, the second test board and the third test board are provided with surface acoustic wave sensors;

when the upper test module descends to be fit with the lower test module, the first test board, the second test board, the third test board, the fourth test board, the fifth test board and the sixth test board form a test cabin of a surrounding structure, the porous material of a cuboid structure is arranged in the test cabin by the test sample and clamped by the upper test module and the lower test module, the wave generator loads stress waves on one surface of the porous material tested sample, the stress waves emitted by the wave generator are absorbed and lost by the porous tested sample in all directions of the material, and the rest stress waves in all directions are received by the surface acoustic wave sensors on the opposite sides of the wave generator and the rest surface acoustic wave sensors in other directions, so that the sound absorption and sound insulation performance test of the porous material tested sample in the first direction is completed; after the lower test module rotates and shifts, a first test board, a second test board, a third test board, a fourth test board, a fifth test board and a sixth test board which are opposite to each other are transposed to form a test chamber of a surrounding structure, and then the sound absorption and sound insulation performance test of the porous material to be tested in the second direction is completed; then, transposition is carried out again to sequentially complete the sound absorption and sound insulation performance test of the porous material sample to be tested in the third direction; the relative translation of the first test board, the second test board and the third test board can change the size of the test chamber to adapt to the change of the size of the sample to be tested; when the upper test module rises away from the lower test module, the sample to be tested of the porous material can be taken out or placed.

As an improvement to the above technical solution, the adjustable deflection test unit further comprises a deflection module; the transposition module comprises a supporting platform, a rotatable rotating platform arranged on the supporting platform, a supporting block and a supporting plate fixed on the rotating platform, and two commutators fixed on the periphery of the rotating platform, wherein the included angle between the centers of the two commutators and the center of the rotating platform is 120 degrees; the first test board is fixed on the supporting block and the supporting plate, and the second test board and the third test board are respectively arranged on the corresponding commutators and ascend or descend relative to the respective commutators so as to ensure the relative displacement of the first test board, the second test board and the third test board; dihedral angles between the test surfaces of the first test board, the second test board and the third test board and a horizontal plane are all 45 degrees; dihedral angles between the test surfaces of the corresponding fourth test board, the corresponding fifth test board and the corresponding sixth test board and a horizontal plane are all 45 degrees; when the upper test module is close to the lower test module, the test surfaces of the first test board, the second test board, the third test board, the fourth test board, the fifth test board and the sixth test board can be tightly matched to form a closed test chamber.

As an improvement to the above technical solution, the second test board is provided with a Z-shaped empty slot, and the first test board, the third test board and the slider are embedded in the Z-shaped empty slot; the sliding block is I-shaped, and the sliding fit of the sliding block and the groove shape is realized along the horizontal direction empty groove of the second test board, so that the sliding block slides along the horizontal groove shape of the second test board in a guiding manner; the back surface of the first test board is provided with a dovetail bulge structure, and the second test board is provided with a dovetail empty groove matched with the dovetail bulge structure in the vertical direction so as to realize sliding fit with the dovetail bulge structure of the first test board along the vertical direction of the second test board; the back that the third surveyed the board is provided with forked tail protruding structure, the slider is corresponding be provided with the third survey the dovetail that surveys board forked tail protruding structure looks adaptation, with the third test board realize the sliding fit of dovetail in the slider, the forked tail length direction that the third surveyed the board parallels with first survey test board forked tail length direction.

As an improvement to the above technical solution, the commutator includes a commutator housing and two angular contact bearings disposed in the commutator housing, the two angular contact bearings are respectively and correspondingly provided with a rotating rod supporting a first gear and a screw rod supporting a second gear, the first gear is engaged with the second gear, the rotating rod is in interference connection with the first gear, and the rotating rod extending out of the commutator is coaxially provided with a scale knob; the screw rod is in interference connection with the second gear, and the screw rod extending out of the commutator is provided with threads and is coaxially connected with a loop bar through the threads; the second test board and the third test board are respectively fixed at the tops of the loop bars of the corresponding commutators, and the staggered angle between the axis direction of the screw rod of the commutators and the upper plane of the rotating platform is 45 degrees; when the rotating rod rotates, the rotating rod and the screw rod driven by the rotating rod gear rotate synchronously, the sleeve rod on the screw rod is moved linearly, and finally the second test plate or the third test plate at the top of the sleeve rod is pushed to move linearly in an obliquely upward or obliquely downward mode.

As an improvement to the above technical solution, the adjustable deflection test device further comprises a cavity unit; the cavity unit comprises an upper cavity and a lower cavity which can be separately matched, wherein a spigot matched with the upper end surface of the lower cavity is arranged on the bottom end surface of the upper cavity so as to ensure that a closed cavity is formed when the upper cavity is matched with the lower cavity; the upper cavity and the lower cavity respectively comprise an open outer cavity and an inner cavity arranged in the inner cavity of the outer cavity, and a sound absorption and vibration reduction layer is arranged between the inner cavity and the outer cavity; the upper end surface of the lower cavity and the spigot end surface of the upper cavity are respectively covered with a sealing layer; go up test module's fourth survey test panel, fifth survey test panel, sixth survey test panel and set up in last cavity and fix the interior cavity bottom at last cavity through the base, test module's first survey test panel, second survey test panel, third survey test panel setting down in the interior cavity of cavity, servo motor, stand are fixed on the interior cavity bottom surface of cavity down.

As an improvement to the above technical solution, the outer cavity and the inner cavity respectively comprise a circular bottom plate and an annular closed cylinder, the circular bottom plate is provided with a groove at the joint with the closed cylinder, the closed cylinder and the circular bottom plate are buckled together by the matching of the grooves and are fixedly connected by a jackscrew penetrating the wall thickness of the two in the radial direction; the sound absorption and vibration reduction layer consists of an inner asbestos vibration reduction layer, a middle organic fiber noise reduction structure layer and an outer porous foam sound insulation layer from inside to outside; the sound absorption and vibration reduction layer is provided with an outer cavity, a closed cylinder of an inner cavity, and a circular bottom plate of the outer cavity and the inner cavity.

As an improvement to the above technical solution, the adjustable deflection test unit further comprises a support platform disposed below the rotary platform, a servo motor fixed below the support platform, and a coupler coaxially connected to the servo motor, wherein the support platform is provided with a central stepped through hole provided with a thrust bearing, the rotary platform is a circular platform, the center of the rotary platform is provided with a rotating shaft connected through a key, the rotating shaft is a stepped shaft, and the rotating shaft penetrates through the thrust bearing and is connected to the coupler; the supporting platform and the upright columns are fixedly arranged on the bottom end face of the inner cavity of the lower cavity.

As an improvement to the above technical solution, the adjustable deflection testing device further comprises a lifting moving unit; the lifting moving unit comprises a bottom plate, a linear motor arranged in the middle of the bottom plate, electric cylinders arranged on the periphery of the bottom plate and a connecting plate connected with piston rods of the electric cylinders, the upper cavity is fixedly connected to the connecting plate, and the lower cavity is fixedly connected to the linear motor.

As an improvement on the technical scheme, position detection sensors are arranged at the top of the upper cavity and the bottom of the lower cavity to ensure that the upper cavity and the lower cavity are relatively parallel.

As an improvement to the above technical solution, an elastic sealing cover is disposed on the back of the second test board, and elastic sealing strips are disposed around the first test board, the second test board, the third test board, the fourth test board, the fifth test board, and the sixth test board to form a closed test chamber when the upper test module and the lower test module are closed, so as to avoid overflow loss of stress waves during the test process; and the inner walls of the inner cavities of the upper cavity and the lower cavity are provided with surface acoustic wave sensors to detect the dissipation effect of the sound absorption and insulation performance testing device for the porous material.

The invention also provides a sound absorption and insulation test method for the porous material, which is based on the adjustable deflection test device to complete the sound absorption and insulation performance test of the porous material, and the test method comprises the following steps:

s1, completing installation of the adjustable deflection testing device, and performing leveling calibration treatment;

s2, placing a cuboid or a cube of a tested porous material sample which is processed in advance according to requirements into a concave cavity formed by a first test plate, a second test plate and a third test plate;

s3, the rotor of the linear motor rotates, drives the whole lower cavity, the rotating module and the lower testing module in the lower cavity to move, and stops moving after being accurately positioned to a set position;

s4, simultaneously descending the extension rods of the four electric cylinders to a preset position, completely closing the upper cavity and the lower cavity, simultaneously completely closing six test boards inside to form a test chamber, and tightly attaching the surfaces of the test boards to the surface of a test sample;

s5, the wave generator emits sound intensity, after passing through the porous material sample, the sensor on the surface of the test board receives signals, and the signals are transmitted to the collecting device through a lead and then transmitted to the computer;

s6, the extension rods of the four electric cylinders rise simultaneously and rise to a set position, a servo motor in the rotating module drives the whole lower testing module to rotate 120 degrees clockwise to reach the set position, the steps S4 and S5 are repeated in sequence to finish the testing of the testing module in the second direction, the testing module rotates 120 degrees clockwise to reach the set position, the steps S4 and S5 are repeated in sequence to finish the testing of the testing module in the third direction, finally, the testing module rotates 120 degrees clockwise to the last position, namely the initial position, and after the testing is finished, the state of the testing device is consistent with the state of the testing device at the beginning of the steps;

in the third rotation displacement, the relative positions of three test boards in the lower test module are adjusted through two commutators to enable the three test boards to be respectively opposite to three test boards of the upper test module so as to form a test chamber, when four electric cylinders descend, the upper cavity and the lower cavity are completely closed, six internal test boards are also completely closed to form the test chamber, and the surfaces of the test boards are tightly attached to the surface of a sample;

s7, the mover of the linear motor drives the whole lower cavity, the rotating module and the lower testing module in the lower cavity to move, and the mover returns to the position of the initial state; and taking out the sample, and finishing the test.

The test principle of the invention is as follows: the method comprises the steps of manufacturing a porous material to be tested into a cuboid structure, loading stress waves on one surface of a cuboid through a wave generator in the testing of a cuboid sample, enabling the stress waves to have field intensity loss after passing through the porous material, receiving the stress waves through an acoustic surface wave sensor on the opposite surface of a selected surface, and measuring the sound absorption and sound insulation performance of the porous material through the relation established by a transfer function through the field intensity difference between the initial stress waves and the received stress waves.

The invention ensures the close fit of the upper cavity and the lower cavity through the electric cylinder and the linear motor and ensures that six test boards form a cavity for placing the porous material sample; the cavity is a closed test chamber; the adjustable deflection test unit comprises a transposition module, an upper test module and an adjustable lower test module, can meet the requirement of multi-surface sound absorption and sound insulation performance test of porous material samples, and can meet the requirement of performance test of samples with different sizes by adjusting the scale knob.

Compared with the prior art, the invention has the following beneficial effects:

1. the invention relates to a sound absorption and insulation test method of a porous material and an adjustable deflection test device thereof, which change the traditional sound absorption and insulation performance test mode of the porous material, the device loads stress waves on the selected surface of a tested sample of the porous material of a cuboid through a wave generator, receives the stress waves through a surface acoustic wave sensor on the opposite surface of the selected surface or other surfaces outside the selected surface, and measures the sound absorption and insulation performance of the porous material through the field intensity difference between the initial stress waves and the received stress waves and the relationship established by a transfer function, so that the test result of the device is more accurate;

2. according to the sound absorption and insulation test method for the porous material and the adjustable displacement test device thereof, the specification and size of the tested sample of the porous material are changed in the test process, the tested sample of the porous material is made into a cuboid, stress wave loading can be carried out on the surfaces of the tested sample of the porous material in three directions, test receiving is carried out on the corresponding surfaces or the other surfaces so as to finish the test of the sound absorption and insulation performance of the tested sample of the porous material in the three directions, the sound absorption and insulation performance of the porous material can be known from the multiple directions, so that a user can use the porous material better, and the sound absorption and insulation performance of the porous material can be brought into full play;

3. according to the sound absorption and insulation test method for the porous material and the adjustable displacement test device thereof, in the test process, the multi-direction performance test of porous materials with different specifications and sizes to be tested is realized through the relative translation adjustment of the first test board, the second test board and the third test board in the lower test module and the displacement adjustment of the displacement module, and the test time is saved through automatic control;

4. according to the sound absorption and insulation test method for the porous material and the adjustable deflection test device for the sound absorption and insulation test method for the porous material, disclosed by the invention, the test cabin consisting of the upper test module and the lower test module and the closed cavity formed when the upper cavity and the lower cavity are matched can prevent the overflow loss of sound waves during testing and the interference of external sound waves on the test device, so that the test result of the device is more accurate.

Generally, the method and the device are simple to operate, the size of the porous material sample can be adjusted, two testing methods are provided, the testing efficiency is high, the testing result is accurate, manual operation in the testing process is not needed, and automatic integrated control is achieved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a top view of the present invention;

FIG. 2 is a cross-sectional view taken along line A-A of FIG. 1;

FIG. 3 is a left side view of the present invention;

FIG. 4 is a bottom view of the upper chamber;

fig. 1-4 illustrate the initial state of the invention, with the sample being measured as a cube of 30mm by 30 mm;

FIG. 5 is a view in the direction E of FIG. 1;

FIG. 6 is a view from direction F of FIG. 1;

FIG. 7 is a view from direction G of FIG. 1;

FIGS. 5-7 are position views of three test plates in the lower chamber, as viewed in the direction E, F, G, when the test specimens of the present invention are rectangular blocks of 50mm by 40mm by 30mm

FIG. 8 is a partial view C of FIG. 2;

FIG. 9 is a perspective view of the position relationship between the slider and the first, second, and third test boards;

fig. 10 is an internal structural view of the commutator;

reference numerals: 1. a base plate; 2. a linear motor; 3. an electric cylinder; 4. a connecting plate; 5-1, an upper cavity; 5-2, lower cavity; 5-3, inner cavity; 5-4, an outer cavity; 5-5, sound absorption and vibration reduction layer; 5-6, sealing layer; 6. a level sensor; 7. a column; 8. a servo motor; 9. a coupling; 10. a support platform; 11. a thrust bearing; 12. a rotating shaft; 13. rotating the platform; 14. a commutator; 14-1, a first gear; 14-2, a second gear; 14-3, angular contact bearings; 15. rotating the rod; 16. a screw; 17. a scale knob; 18. a first test board; 19. a slider; 20. a third test board; 21. a second test board; 22. a support block; 23. a support plate; 24. an elastic sealing cover; 25. an elastic sealing strip; 26. a wave generator; 27. a fourth test board; 28. a fifth test board; 29. a sixth test board; 30. a base; 31. 32, a surface acoustic wave sensor; 33. a loop bar; 551. an asbestos vibration-damping layer; 552. an organic fiber noise reduction structure layer; 553. a porous foam sound insulating layer.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "inside", "outside", "left", "right", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, or the orientations or positional relationships that the products of the present invention are conventionally placed in use, or the orientations or positional relationships that are conventionally understood by those skilled in the art, and are used for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

Furthermore, the terms "first," "second," and the like are used merely to distinguish one description from another, and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it is also to be noted that, unless otherwise explicitly stated or limited, the terms "disposed" and "connected" are to be interpreted broadly, and for example, "connected" may be a fixed connection, a detachable connection, or an integral connection; can be mechanically or electrically connected; the connection may be direct or indirect via an intermediate medium, and may be a communication between the two elements. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

As shown in fig. 1-10, the adjustable deflection testing apparatus of the present invention includes an indexing module and an indexing module.

The indexing module comprises a supporting platform 10, a rotatable rotating platform 13 arranged on the supporting platform 10 and a commutator 14 fixed on the periphery of the rotating platform 13, wherein the rotating platform 13 is fixedly provided with a supporting block 22 and a supporting plate 23 which are separated from each other, and the commutator 14 is a gear type commutator;

the indexing module comprises a lower testing module carried on a rotating platform 13 (the rotating platform 13 is superposed on a supporting platform 10, the supporting platform 10 is carried in a lower cavity, and the specific structure of the part is mentioned later); the upper testing module is opposite to the lower testing module and is carried in the upper cavity 5-1; the upper cavity and the lower cavity can be separated and matched, so that the upper test module and the lower test module are sealed, and the leakage of stress waves is prevented;

the second test board 21 is provided with a Z-shaped empty slot, and a first test board 18, a third test board 20 and a slide block 19 are embedded in the Z-shaped empty slot; the slide block 19 is I-shaped, and the slide block 19 is in sliding fit with the groove shape along the horizontal direction empty groove of the second test board 21, so that the slide block 19 slides along the horizontal groove shape of the second test board 21 in a guiding manner; the back surface of the first test board 18 is provided with a dovetail protrusion structure, and the second test board 21 is provided with a dovetail empty slot matched with the dovetail protrusion structure in the vertical direction so as to realize sliding fit with the dovetail protrusion structure of the first test board 18 along the vertical direction of the second test board 21; the back of the third test board 20 is provided with a dovetail protrusion structure, the slider 19 is correspondingly provided with a dovetail groove matched with the dovetail protrusion structure of the third test board 20, the dovetail groove is in sliding fit with the third test board 20 in the slider 19, and the dovetail length direction of the third test board 20 is parallel to the dovetail length direction of the first test board 18. The first test board 18, the second test board 21 and the third test board 20 are perpendicular to each other in pairs so that the test surfaces of the three test boards form a semi-surrounding structure, and the surface acoustic wave sensors 31 are arranged on the test surfaces of the first test board 18, the second test board 21 and the third test board 20.

The upper test module comprises a base 30, a fourth test board 27, a fifth test board 28 and a sixth test board 29 are fixedly arranged on the lower end surface of the base 30, the fourth test board 27, the fifth test board 28 and the sixth test board 29 are vertical in pairs so that test surfaces of the three test boards form a semi-surrounding structure, surface acoustic wave sensors 31 are arranged on the test surfaces of the fourth test board 27, the fifth test board 28 and the sixth test board 29, and a wave generator 26 is arranged on one of the fourth test board 27, the fifth test board 28 and the sixth test board 29;

when the upper test module is matched with the lower test module, a test surrounding structure with a cuboid test cavity is continuously formed between the surfaces of the first to sixth test boards, and the porous material is placed in a test cabin formed by the test cavity in the test sample to complete the sound absorption and sound insulation performance test of the porous material to be tested.

The back surface of the first test board 18 is provided with a dovetail, and the second test board 21 is provided with a dovetail groove outside the Z-shaped hollow groove so as to be in sliding fit with the first test board 18; the back surface of the third test board 20 is provided with a dovetail, the slide block 19 is correspondingly provided with a dovetail groove to be in sliding fit with the third test board 20, and the length direction of the dovetail of the third test board 20 is parallel to the length direction of the dovetail of the first test board 18; the slider 19 is i-shaped, and the second test board 21 is in sliding fit with the i-shaped slider in the Z-shaped empty slot, so that the slider 19 slides along the guide of the second test board 21. The dihedral angles of the first test board 18, the second test board 21, the third test board 20 and the plane on the rotary platform 13 are all 45 degrees; the dihedral angles of the fourth test plate 27, the fifth test plate 28, the sixth test plate 29 and the plane on the rotary platform 13 are also 45 degrees.

Two angular contact bearings 14-3 are arranged in the box body of the commutator 14, a rotating rod 15 for supporting a first gear 14-1 and a screw 16 for supporting a second gear 14-2 are respectively arranged on the two angular contact bearings 14-3, the first gear 14-1 is meshed with the second gear 14-2, a key groove is arranged on the rotating rod 15 and is in interference connection with the first gear 14-1 through a key, the first gear 14-1 and part of the rotating rod are positioned in the commutator 14, and a scale knob 17 is coaxially arranged on the rotating rod 15 extending out of the commutator 14; the screw 16 is provided with a key groove and is in interference fit connection with the second gear 14-2 through a key, the second gear 14-2 and part of the screw 16 are positioned in the commutator, the screw 16 extending out of the commutator 14 is provided with threads, and the screw is coaxially provided with a loop bar 33 in threaded connection with the screw; the other end of the loop bar 33 of one commutator is fixed on the second test board 21 through a screw, and the other end of the loop bar 33 of the other commutator is fixed on the back surface of the third test board 20 through a screw; the stagger angle between the axial direction of the screw rod 16 of the commutator and the upper plane of the rotating platform 13 is 45 degrees.

The adjustable deflection test unit further comprises a supporting platform 10 arranged below the rotating platform 13, a servo motor 8 fixed below the supporting platform 10 and a coupler 9 coaxially connected with the servo motor 8, wherein the supporting platform 10 is provided with a central stepped through hole, the central stepped through hole is provided with a thrust bearing 11, the rotating platform 13 is a circular platform, the center of the rotating platform is provided with a rotating shaft 12 connected through a key, the rotating shaft 12 is a stepped shaft and penetrates through the thrust bearing 11 to be connected with the coupler 9; the supporting platform 10 is provided with a vertical column 7 under the periphery.

The adjustable deflection testing device also comprises a cavity unit; the cavity unit comprises an upper cavity 5-1 and a lower cavity 5-2 which can be separately matched, wherein a spigot matched with the upper end surface of the lower cavity 5-2 is arranged on the end surface of the bottom of the upper cavity 5-1 so as to ensure that a closed cavity is formed when the upper cavity 5-1 is matched with the lower cavity 5-2; the upper cavity 5-1 and the lower cavity 5-2 both comprise an open outer cavity 5-4 and an inner cavity 5-3 arranged in the inner cavity of the outer cavity 5-4, and a sound absorption and vibration reduction layer 5-5 is arranged between the inner cavity 5-3 and the outer cavity 5-4; the upper end surface of the lower cavity 5-2 and the spigot end surface of the upper cavity 5-1 are respectively covered with a sealing layer 5-6; the upper testing module is arranged in an inner cavity 5-3 of the upper cavity 5-1, the lower testing module is arranged in the inner cavity 5-3 of the lower cavity 5-2, and the servo motor 8 and the upright post 11 are fixed on the bottom surface of the inner cavity 5-3 of the lower cavity 5-2.

The outer cavity 5-4 and the inner cavity 5-3 are respectively formed by inserting a closed cylinder end face into a bottom plate with an end plane provided with a circular groove and buckling, a groove is arranged at the joint of the bottom plate and the closed cylinder, the closed cylinder and the bottom plate are buckled together through the matching of the grooves and are fixedly connected by a jackscrew penetrating through the wall thickness of the closed cylinder and the bottom plate along the radial direction; the sound absorption and vibration reduction layer 5-5 consists of an inner asbestos vibration reduction layer 551, a middle organic fiber noise reduction structure layer 552 and an outer porous foam sound insulation layer 553 from inside to outside.

The adjustable deflection testing device also comprises a lifting moving unit; the lifting moving unit comprises a bottom plate 1, a linear motor 2 arranged in the middle of the bottom plate 1, electric cylinders 3 arranged around the bottom plate 1 and a connecting plate 4 connected with piston rods of the electric cylinders 3, wherein the electric cylinders 3 are fixed on the bottom plate 1 through flanges at the bottom by screws, an upper cavity 5-1 is fixedly connected on the connecting plate 4 by bolts and nuts, and a lower cavity 5-2 is fixedly connected on the linear motor 2 by screws. And position detection sensors 6 are arranged at the top of the upper cavity 5-1 and the bottom of the lower cavity 5-2 to ensure that the upper cavity and the lower cavity are relatively parallel.

An elastic sealing cover 24 is arranged on the back surface of the second test board 21, and elastic sealing strips 25 are arranged on the peripheries of the first test board 18, the second test board 21, the third test board 20, the fourth test board 27, the fifth test board 28 and the sixth test board 29 so as to form a closed test chamber when the upper test module and the lower test module are closed, thereby avoiding the overflow loss of stress waves in the test process; and the inner walls of the inner cavities 5-3 of the upper cavity 5-1 and the lower cavity 5-2 are provided with the surface acoustic wave sensors 32 so as to detect the dissipation effect of the sound absorption and insulation performance testing device for the porous material.

This testing arrangement can test the cuboid and include the square sample, the test range of cuboid sample:

length: 20 mm-50 mm, the second test plate 21 controlling its length;

width: 30 mm-40 mm, the length of which is controlled by a third test plate 20;

high: 30 mm.

The dimensions of the porous material sample in the three directions may be arbitrarily combined within the above range, for example: rectangular and square specimens 50mm by 40mm by 30mm and 30mm by 30 mm.

Electric jar 3 has four, and specification parameter is the same, and electric jar 3 bilateral symmetry arranges on bottom plate 1, and two on the left side, two on the right, and it is perpendicular to keep with bottom plate 1 to electric jar 3 bottoms have the flange, and threaded hole is gone up to bottom plate 1, and electric jar 3 is installed fixedly through the bolt for the flange. The linear motor is arranged at the central symmetry position of the left electric cylinder 3 and the right electric cylinder 3, the stator is fixed on the bottom plate 1, the rotor and the rotor seat are connected with the outer cavity 5-4 of the lower cavity 5-2, the lower cavity 5-2 and the adjustable deflection test unit inside the lower cavity can be accurately positioned under the upper cavity 5-1, and the upper cavity 5-1 and the lower cavity 5-2 are driven by the electric cylinder 3 to form close fit.

An extension rod of the electric cylinder 3 is an external thread, and a through hole is formed in the upper cavity connecting plate 4 and is fixed through a gasket nut; the upper cavity connecting plate 4 is connected with the upper cavity 5-1 through a stud, a threaded hole is formed in the outer cavity 5-4 of the upper cavity 5-1, and the threaded hole does not penetrate through the sound insulation and vibration reduction layer 5-5; the mouths of the upper cavity 5-1 and the lower cavity 5-2 are rabbets, and the outer cavity 5-3 at the mouth of the upper cavity 5-1 just wraps the lower cavity 5-2; the upper cavity and the lower cavity can be separated and matched through simultaneous lifting of the four electric cylinders 3, and the stroke of the electric cylinders 3 is larger than the sum of the height of the upper cavity and the lifting height of the upper cavity 5-1; the top of the upper cavity 5-1 is provided with a horizontal sensor 6, and the upper cavity 5-1 and the lower cavity 5-2 are kept parallel through the respective ascending and descending of the four electric cylinders 3.

The inner cavity 5-1 is similar to the outer cavity 5-2 and is formed by inserting a closed cylinder end face into a bottom plate with an end plane provided with a circular groove and buckling, a groove is arranged at the joint of the bottom plate and the closed cylinder, the closed cylinder and the bottom plate are buckled together through the matching of the groove and are fixedly connected by a jackscrew penetrating through the wall thickness of the closed cylinder and the bottom plate along the radial direction; the sound absorption and vibration reduction layer 5-5 consists of an inner asbestos vibration reduction layer 551, a middle organic fiber noise reduction structure layer 552 and an outer porous foam sound insulation layer 553 from inside to outside. The purpose of such a structure is to reduce the influence of the outside world on the experiment.

The supporting platform 10 of the rotating module is a circular platform and is fixed on the bottom surface inside the lower cavity 5-2 through four circular uniformly distributed stand columns 7, the lower ends of the stand columns 7 only penetrate through the inner cavity 5-3 of the lower cavity 5-2 and do not penetrate through the vibration reduction and sound absorption layer 5-4, and the upper ends of the stand columns are matched with threaded blind holes of the supporting platform; the servo motor 8 is arranged below the supporting platform and is fixed on the inner cavity 5-3 of the lower cavity 5-2 through a screw, a stepped through hole is formed in the center of the supporting platform 10, a thrust bearing 11 is installed and penetrates through a rotating shaft 12, the thrust bearing 11 bears the rotating shaft 12 and bears the gravity of the whole lower testing module, the lower end of the rotating shaft 12 is connected with the servo motor 8 through a coupler, and the upper end of the rotating shaft is connected with a rotating platform 13 through a key connection; the indexing angle of the servo motor in the device needs to be matched with the overall requirements of the device, and the indexing angle is 0 degree, 120 degrees, 240 degrees and 360 degrees.

The supporting block 22 and the supporting plate 23 are fixed on the rotary platform 13, the first testing plate 18 is fixed on the supporting block 22 and the supporting plate 23, a dovetail structure is arranged on the first testing plate 18 and is matched with a dovetail groove of the second testing plate 21, the first testing plate 21 has a supporting function and has a guiding function when the second testing plate 21 moves; the third test board 20 also has a dovetail and is matched with a dovetail groove in the thickness direction of the slide block 19, the slide block 19 is I-shaped along the lifting direction of the slide block 19, a square empty groove is arranged on the edge of the L-shaped empty groove of the second test board 21 so as to be in sliding fit with the I-shaped of the slide block, so that the slide block slides along the guide direction of the second test board 21, and the sliding distance is 10 mm; the upper side of the second test board 21 is provided with a hole which is connected together in a fixed shape, and mounting positions are reserved for the first test board 18, the slide block 19 and the third test board 20; the first test board 18, the third test board 20 and the second test board 21 are perpendicular to each other two by two, and the first test board 18 and the third test board 20 penetrate the second test board 21 through the L-shaped empty groove, and the upper surface of the first test board 18 and the side surface of the third test board 20 are attached together. The surface acoustic wave sensors 31 are uniformly distributed on the surfaces of the test positions of the three test boards (namely, the test surfaces, and the opposite surfaces are called as back surfaces), and receive the residual stress waves after passing through the test sample, and the dihedral angles of the three test boards and the upper plane of the rotary platform 13 are all 45 degrees.

The shape of the porous material tested sample is cuboid or cube, the size of the porous material tested sample is adjustable and not fixed, when the sizes of the tested samples are different, the positions of three test plates are changed through the adjusting device, so that the size of a cavity containing the sample is changed, and the surface of the sample is tightly attached to the surface of the test plate. The lower testing module needs to move the third testing board 20 and the second testing board 21, so two sets of adjusting devices are needed, each set of adjusting device is composed of a commutator 14, a rotary rod 15, a screw rod 16, a scale knob 17 and a loop bar 33, the rotary motion of the rotary rod 15 is converted into the rotary motion of the screw rod 16 through the commutator 14, the axis of the rotary rod 15 is perpendicular to the rotary platform 13, the axis of the screw rod 16 is in the normal direction of the third testing board 20 or the second testing board 21, the included angle between the axis of the rotary rod 15 and the axis of the screw rod 16 is 45 degrees, the inside of the commutator 14 is gear meshing motion, the stagger angle is 45 degrees, the screw rod 16 is coaxially in threaded connection with the loop bar 33, the other end of the loop bar 33 is fixed on the back of the second testing board 21 and the third testing board 20 through a screw, the rotary motion of the screw rod 16 is converted into linear motion through the loop bar 33 to push the second, the purpose of adjustment is achieved.

The wave generator 26 is embedded into a circular hole of the fourth test board 27, the surface of the wave generator 26 is overlapped with the upper surface of the fourth test board 27, and stress waves are emitted in the test process; the fourth test board 27, the fifth test board 28 and the sixth test board 29 have the same length, width and height, are square, have saw sensors 31 uniformly distributed on the surfaces, are perpendicular to each other in pairs to form three faces of the square, have diagonal lines perpendicular to the bottom surface of the upper cavity 5-1, and have dihedral angles of 45 degrees with the bottom surface of the upper cavity 5-1. The test boards are all mounted on a base 30 and fixed on the inner cavities 5-3 by screws.

The elastic sealing strips 25 are inlaid in the gaps and the side faces of the test board, so that when the upper test module and the lower test module are closed, a closed cavity is formed, and the sound waves cannot overflow and lose in the test process. A surface acoustic wave sensor 32 is arranged on the inner wall of the inner cavity for detecting the dissipative effect of the device.

The testing principle of the device is as follows: for testing a cuboid sample, a surface A of the cuboid is loaded by a wave generator, the stress wave passes through a porous material and then generates field intensity loss of the stress wave, and a surface B of the opposite surface of the surface A receives the stress wave through a surface acoustic wave sensor, so that the sound absorption and sound insulation performance of the porous material is measured. The test mode of the invention has two types; for testing a cuboid sample, loading the surface A and receiving the surface B; the final test results are the same as for B-side loading and a-side reception. The first test method comprises the following steps: the method comprises the steps of emitting stress waves on one surface of a sample, receiving the stress waves on the opposite surface of the sample, conducting transposition at 0 degree, 120 degrees and 240 degrees through electric cylinder lifting and a servo motor, realizing performance tests on three surfaces, and carrying out various comparison modes on test data to explore the performance of the porous material; the second test method comprises the following steps: and (3) adding a carrier wave on one surface of the sample, testing and receiving the other five surfaces, loading one surface and receiving five surfaces by lifting and rotating 120 degrees and 240 degrees.

According to the invention, only when the size of the sample is adjusted, manual operation is needed, and in the rest measuring process, the electric cylinder drives the upper cavity to lift, the linear motor rotor drives the lower cavity to move, and the servo motor rotates, so that automatic control can be performed through programs, the time is saved, and the time consumed for always disassembling the sample is avoided.

Procedure when the invention works in the initial state

[1] Taking fig. 2 and fig. 3 as an example for explanation, after the device is connected with the collecting device and the computer and other equipment, the computer software is firstly opened to perform leveling calibration processing;

[2] preparing a 30mm by 30mm square sample of the porous material and loading it into the recessed cavities formed by the first test plate 18, the third test plate 20 and the second test plate 21;

[3] selecting a test mode, clicking a start button, driving the whole lower cavity 5-2, a rotating module inside the lower cavity and a lower test module to move by a rotor of the linear motor 2, and stopping the rotor after the rotor is accurately positioned to a set position;

[4] the extension rods of the four electric cylinders 3 descend simultaneously to a preset position, the upper cavity 5-1 and the lower cavity 5-2 are completely closed, meanwhile, the six test boards inside are also completely closed to form a test chamber, and the surfaces of the test boards are tightly attached to the surface of a sample.

[5] The wave generator 26 emits sound intensity, and after passing through the porous material sample, the sensor 31 on the surface of the test board receives signals, and transmits the signals to the collecting device through a lead and then to the computer.

[6] The extension rods of the four electric cylinders 3 rise simultaneously to reach a set position, and the servo motors 8 in the rotating module drive the whole lower testing module to rotate 120 degrees clockwise to reach the set position.

[7] Repeating the steps (4), (5) and (6) twice in sequence.

[8] At this time, the state of the testing device is consistent with the state after the step [3] is finished.

[9] The mover of the linear motor drives the whole lower cavity 5-2 and the rotating module and the lower testing module inside the whole lower cavity to move and return to the position of the initial state.

[10] And taking out the sample, and finishing the test.

When the size of the porous material sample is not 30mm cube, the operation process only needs to change the operation step [2] in the initial state into:

[11] the size value of the sample is within the measuring range of the testing device, the two scale knobs 17 are adjusted to rotate to the same size as the sample, the third testing plate 20 and the second testing plate 21 are moved to form a cavity matched with the sample, and then the sample is placed in the cavity.

For example: when the size of the sample of porous material is a cuboid of 50mm 40mm 30mm, the scale knob is rotated to control the knob of the second test plate 21 to rotate to the scale of 50, and the knob of the third test plate 20 to rotate to the scale of 40, and fig. 5, 6 and 7 are position diagrams of the first test plate 18, the third test plate 20 and the second test plate 21 in the direction of E, F, G, and the sample is placed in the position diagrams for testing.

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

Claims

1. An adjustable deflection test device is characterized by at least comprising an adjustable deflection test unit, wherein the adjustable deflection test unit at least comprises a test module; the test module comprises an upper test module and a lower test module which can be close to or far away and can be matched in an adjustable way; the upper test module is a liftable module, is far away from or close to the lower test module through lifting, and comprises a fourth test board, a fifth test board and a sixth test board which are mutually intersected to form a right angle, and the relative positions of the fourth test board, the fifth test board and the sixth test board are fixed to form a concave-upward semi-surrounding structure; the lower test module is a rotatable position-changing module and comprises a first test board, a second test board and a third test board which are mutually intersected to form a right angle, and the first test board, the second test board and the third test board can relatively move and form a concave semi-surrounding structure; one of the fourth test board, the fifth test board and the sixth test board is provided with a wave generator, and the other two test boards, the first test board, the second test board and the third test board are provided with surface acoustic wave sensors;

2. The adjustable deflection testing device of claim 1, wherein: the adjustable deflection test unit also comprises a transposition module; the transposition module comprises a supporting platform, a rotatable rotating platform arranged on the supporting platform, a supporting block and a supporting plate fixed on the rotating platform, and two commutators fixed on the periphery of the rotating platform, wherein the included angle between the centers of the two commutators and the center of the rotating platform is 120 degrees; the first test board is fixed on the supporting block and the supporting plate, and the second test board and the third test board are respectively arranged on the corresponding commutators and ascend or descend relative to the respective commutators so as to ensure the relative displacement of the first test board, the second test board and the third test board; dihedral angles between the test surfaces of the first test board, the second test board and the third test board and a horizontal plane are all 45 degrees; dihedral angles between the test surfaces of the corresponding fourth test board, the corresponding fifth test board and the corresponding sixth test board and a horizontal plane are all 45 degrees; when the upper test module is close to the lower test module, the test surfaces of the first test board, the second test board, the third test board, the fourth test board, the fifth test board and the sixth test board can be tightly matched to form a closed test chamber.

3. The adjustable deflection testing device of claim 2, wherein: the second test board is provided with a Z-shaped empty groove, and a first test board, a third test board and a slide block are embedded in the Z-shaped empty groove; the sliding block is I-shaped, and the sliding fit of the sliding block and the groove shape is realized along the horizontal direction empty groove of the second test board, so that the sliding block slides along the horizontal groove shape of the second test board in a guiding manner; the back surface of the first test board is provided with a dovetail bulge structure, and the second test board is provided with a dovetail empty groove matched with the dovetail bulge structure in the vertical direction so as to realize sliding fit with the dovetail bulge structure of the first test board along the vertical direction of the second test board; the back that the third surveyed the board is provided with forked tail protruding structure, the slider is corresponding be provided with the third survey the dovetail that surveys board forked tail protruding structure looks adaptation, with the third test board realize the sliding fit of dovetail in the slider, the forked tail length direction that the third surveyed the board parallels with first survey test board forked tail length direction.

4. The adjustable deflection testing device of claim 3, wherein: the commutator comprises a commutator box body and two angular contact bearings arranged in the commutator box body, wherein a rotary rod for supporting a first gear and a screw rod for supporting a second gear are respectively and correspondingly arranged on the two angular contact bearings, the first gear is meshed with the second gear, the rotary rod is in interference connection with the first gear, and a scale knob is coaxially arranged on the rotary rod extending out of the commutator; the screw rod is in interference connection with the second gear, and the screw rod extending out of the commutator is provided with threads and is coaxially connected with a loop bar through the threads; the second test board and the third test board are respectively fixed at the tops of the loop bars of the corresponding commutators, and the staggered angle between the axis direction of the screw rod of the commutators and the upper plane of the rotating platform is 45 degrees; when the rotating rod rotates, the rotating rod and the screw rod driven by the rotating rod gear rotate synchronously, the sleeve rod on the screw rod is moved linearly, and finally the second test plate or the third test plate at the top of the sleeve rod is pushed to move linearly in an obliquely upward or obliquely downward mode.

5. The adjustable deflection testing device of claim 4, wherein: the adjustable deflection testing device also comprises a cavity unit; the cavity unit comprises an upper cavity and a lower cavity which can be separately matched, wherein a spigot matched with the upper end surface of the lower cavity is arranged on the bottom end surface of the upper cavity so as to ensure that a closed cavity is formed when the upper cavity is matched with the lower cavity; the upper cavity and the lower cavity respectively comprise an open outer cavity and an inner cavity arranged in the inner cavity of the outer cavity, and a sound absorption and vibration reduction layer is arranged between the inner cavity and the outer cavity; the upper end surface of the lower cavity and the spigot end surface of the upper cavity are respectively covered with a sealing layer; go up test module's fourth survey test panel, fifth survey test panel, sixth survey test panel and set up in last cavity and fix the interior cavity bottom at last cavity through the base, test module's first survey test panel, second survey test panel, third survey test panel setting down in the interior cavity of cavity, servo motor, stand are fixed on the interior cavity bottom surface of cavity down.

6. The adjustable deflection testing device of claim 5, wherein: the outer cavity and the inner cavity respectively comprise a circular bottom plate and an annular closed cylinder, a groove is formed in the joint of the circular bottom plate and the closed cylinder, the closed cylinder and the circular bottom plate are buckled together through the matching of the grooves and are fixedly connected by a jackscrew penetrating through the wall thickness of the closed cylinder and the circular bottom plate along the radial direction; the sound absorption and vibration reduction layer consists of an inner asbestos vibration reduction layer, a middle organic fiber noise reduction structure layer and an outer porous foam sound insulation layer from inside to outside; the sound absorption and vibration reduction layer is provided with an outer cavity, a closed cylinder of an inner cavity, and a circular bottom plate of the outer cavity and the inner cavity.

7. The adjustable deflection testing device of claim 6, wherein: the adjustable deflection test unit also comprises a supporting platform arranged below the rotating platform, a servo motor fixed below the supporting platform and a coupler coaxially connected with the servo motor, wherein the supporting platform is provided with a central stepped through hole which is provided with a thrust bearing, the rotating platform is a circular platform, the center of the rotating platform is provided with a rotating shaft connected through a key, and the rotating shaft is a stepped shaft and penetrates through the thrust bearing to be connected with the coupler; the supporting platform and the upright columns are fixedly arranged on the bottom end face of the inner cavity of the lower cavity.

8. The adjustable deflection testing device of claim 6, wherein: the adjustable deflection testing device also comprises a lifting moving unit; the lifting moving unit comprises a bottom plate, a linear motor arranged in the middle of the bottom plate, electric cylinders arranged around the bottom plate and a connecting plate connected with piston rods of the electric cylinders, the upper cavity is fixedly connected to the connecting plate, and the lower cavity is fixedly connected to the linear motor; and position detection sensors are arranged at the top of the upper cavity and the bottom of the lower cavity to ensure that the upper cavity and the lower cavity are relatively parallel.

9. The adjustable deflection testing device of claim 3, wherein: an elastic sealing cover is arranged on the back of the second test board, and elastic sealing strips are arranged on the peripheries of the first test board, the second test board, the third test board, the fourth test board, the fifth test board and the sixth test board so that a closed test chamber is formed when the upper test module and the lower test module are closed, and overflowing loss of stress waves in the test process is avoided; and the inner walls of the inner cavities of the upper cavity and the lower cavity are provided with surface acoustic wave sensors to detect the dissipation effect of the sound absorption and insulation performance testing device for the porous material.

10. A sound absorption and insulation test method for porous materials by using the adjustable deflection test device as claimed in any one of claims 1 to 9 to test the sound absorption and insulation performance of the porous materials, which is characterized in that: the testing method comprises the following steps: