A piezoelectric material piezoelectric constant measuring device

Abstract

The application relates to the technical field of piezoelectric constant measurement of piezoelectric materials, and discloses a piezoelectric constant measurement device for piezoelectric materials, which comprises a machine body, a measurement mechanism, a static force applying mechanism and a dynamic force applying mechanism. The measurement mechanism comprises a first conductive part, a second conductive part and a measurement assembly. The first conductive part is arranged in a spaced mode with the second conductive part. The measurement assembly is electrically connected with the first conductive part and the second conductive part, and is used for measuring the charge amount released by the piezoelectric material when the piezoelectric material is pressed. The static force applying mechanism is connected with the first conductive part and the machine body, and is used for applying a static force to the piezoelectric material through the first conductive part. The dynamic force applying mechanism comprises a dynamic force sensor and a vibration exciter. The vibration exciter is connected with the machine body and the dynamic force sensor, and is connected with the second conductive part through the dynamic force sensor, and is used for applying a dynamic force to the piezoelectric material. The piezoelectric constant of the piezoelectric material can be accurately measured, and the interference of the error of the reference material on the piezoelectric constant measurement of the piezoelectric material is avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of piezoelectric constant measurement of piezoelectric material, and particularly relates to a piezoelectric constant measurement device of piezoelectric material. BACKGROUND

[0002] As a functional material of mutual conversion between mechanical performance and electrical performance, piezoelectric ceramics are widely used in communication, measurement, biology, aerospace and other fields. In the process of piezoelectric ceramic production, the piezoelectric parameters of the produced piezoelectric ceramics need to be measured.

[0003] The commonly used piezoelectric constant measurement device includes electromagnetic drive, two conductive parts, reference sample, insulating house and probe. Specifically, the measured sample is fixed between the two conductive parts, vibration is generated by the alternating signal of electromagnetic drive, the force on the measured sample changes regularly, and the piezoelectric coefficient of the sample is obtained by comparing the relationship between the electrical signal generated by the measured sample and the electrical signal generated by the reference sample with known piezoelectric coefficient.

[0004] However, since the D33 piezoelectric coefficient of the reference sample itself may have errors, the piezoelectric constant of the new piezoelectric ceramic cannot be measured by the reference sample with possible errors, and it is impossible to determine whether the measured piezoelectric constant of the piezoelectric ceramic is correct. SUMMARY

[0005] The present application aims to overcome the above technical deficiencies, and provides a piezoelectric constant measurement device of piezoelectric material, which solves the technical problem of inaccurate measurement of piezoelectric constant of piezoelectric ceramic by the reference sample in the prior art.

[0006] To achieve the above technical purpose, the present application adopts the following technical scheme:

[0007] The present application provides a piezoelectric constant measurement device of piezoelectric material, which comprises a body, a measurement mechanism, a static force applying mechanism and a dynamic force applying mechanism. The measurement mechanism comprises a first conductive part, a second conductive part and a measurement assembly. The first conductive part and the second conductive part are arranged at intervals. The measurement assembly is electrically connected with the first conductive part and the second conductive part, and is used for measuring the amount of charge released by the piezoelectric material when it is pressed. The static force applying mechanism is connected with the first conductive part and the body, and is used for applying static force to the piezoelectric material through the first conductive part. The dynamic force applying mechanism comprises a dynamic force sensor and a vibration exciter. The vibration exciter is connected with the body and the dynamic force sensor, and is connected with the second conductive part through the dynamic force sensor, and is used for applying dynamic force to the piezoelectric material.

[0008] In some embodiments, the vibration exciter comprises a fixed part, a permanent magnet, a movable part, a vibration coil and a power supply, the fixed part is connected to the fixed part, the permanent magnet is connected to the fixed part, the movable part is slidingly connected to the fixed part, and the movable part is connected to the dynamic force sensor and connected to the second conductive part through the dynamic force sensor, the vibration coil is connected to the movable part, the power supply is electrically connected to the vibration coil, and the power supply outputs a driving electrical signal to the vibration coil to drive the vibration coil to drive the movable part to apply a dynamic force to the piezoelectric material.

[0009] In some embodiments, the measuring mechanism further comprises a phase-locked loop module, which is electrically connected to the measuring component and the dynamic force sensor, and is used to detect the phase of the force signal collected by the dynamic force sensor and the phase of the charge signal collected by the measuring component.

[0010] When the polarities of the phases of the force signal and the charge signal are the same, the piezoelectric material is facing upwards;

[0011] When the polarities of the phases of the force signal and the charge signal are opposite, the piezoelectric material is facing downwards.

[0012] In some embodiments, the phase-locked loop module is further electrically connected to the power supply and is used to detect the phase difference between the force signal and the charge signal in real time, lock the phase difference, and output a phase adjustment signal to the control module of the power supply.

[0013] In some embodiments, the power supply can output electrical signals of different sizes and different frequencies to the vibration coil, so as to adjust the frequency and size of the dynamic force output by the vibration coil.

[0014] In some embodiments, the static force applying mechanism comprises a transmission assembly and a driving motor, the transmission assembly is connected to the first conductive part, and the driving motor is connected to the transmission assembly and the machine body, and is used to connect the first conductive part through the transmission assembly to drive the first conductive part to move linearly.

[0015] In some embodiments, the static force applying mechanism further comprises a static force sensor, the transmission assembly is connected to the first conductive part through the static force sensor, and the static force sensor is used to measure the static force applied to the piezoelectric material.

[0016] In some embodiments, the dynamic force applying mechanism further comprises at least one first elastic sheet, the first elastic sheet is connected to the fixed part and the movable part, and is used to provide elastic force for resetting the movable part after movement.

[0017] In some embodiments, the dynamic force applying mechanism further comprises a second elastic sheet connecting the second conductive part and the fixing member, and the rigidity of the second elastic sheet is greater than that of the first elastic sheet, and the dynamic force sensor is connected to the second elastic sheet and connected to the second conductive part through the second elastic sheet.

[0018] In some embodiments, the first conductive part and the second conductive part are coaxial, and the opposite ends are spherical.

[0019] Compared with the prior art, the piezoelectric constant measuring device for piezoelectric material provided by the application measures the piezoelectric constant of piezoelectric ceramic, sets the piezoelectric material between the first conductive part and the second conductive part, applies static force to the piezoelectric ceramic through the static force applying mechanism, and then applies dynamic force with varying size to the piezoelectric material through the dynamic force applying mechanism.

[0020] The piezoelectric constant measurement formula of the piezoelectric ceramic is:

[0021] D33=Q / F

[0022] In the formula, Q is the released charge of the sample, and F is a low-frequency alternating vibration force applied to both ends of the sample.

[0023] The dynamic force F borne by the piezoelectric ceramic is detected by the dynamic force sensor, and the amount of charge Q released by the piezoelectric ceramic when subjected to pressure is detected by the measuring assembly, so that the actual piezoelectric constant of the piezoelectric material can be obtained, the influence of the pressure change caused by human factors on the D33 value is effectively eliminated, and the influence of the error of the reference sample on the measurement accuracy of the piezoelectric ceramic is effectively eliminated. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 is a structural schematic view of the piezoelectric constant measuring device for piezoelectric material provided by an embodiment of the application;

[0025] Figure 2 is a structural schematic view of the piezoelectric constant measuring device for piezoelectric material provided by an embodiment of the application;

[0026] Figure 3 is Figure 2 is a partial enlarged view of position A in FIG. 1;

[0027] Figure 4 is a sectional view of the measuring mechanism, the static force applying mechanism and the dynamic force applying mechanism in the piezoelectric constant measuring device for piezoelectric material provided by an embodiment of the application;

[0028] Figure 5 is Figure 4 is a partial enlarged view of position B in FIG. 2;

[0029] Figure 6Figure 1 is a structural schematic diagram of two first elastic sheets, a fixed block and a connecting portion in a piezoelectric material piezoelectric constant measuring device according to an embodiment of the present application;

[0030] Figure 7 Figure 2 is a structural schematic diagram of a first elastic sheet in a piezoelectric material piezoelectric constant measuring device according to an embodiment of the present application;

[0031] Figure 8 Figure 3 is a sectional view of a measuring mechanism, a static force applying mechanism and a dynamic force applying mechanism in a piezoelectric material piezoelectric constant measuring device according to an embodiment of the present application;

[0032] Figure 9 Figure 4 is a circuit connection principle diagram among a measuring mechanism, a dynamic force sensor, a power supply and an excitation coil in a piezoelectric material piezoelectric constant measuring device according to an embodiment of the present application;

[0033] Figure 10 Figure 5 is a sectional view of a part structure of an excitation vibrator in a piezoelectric material piezoelectric constant measuring device according to an embodiment of the present application.

[0034] Legend of reference signs:

[0035] Machine body 1;

[0036] Measuring mechanism 2;

[0037] First conductive portion 21;

[0038] Second conductive portion 22;

[0039] Measuring assembly 23;

[0040] Phase-locked loop module 24;

[0041] Static force applying mechanism 3;

[0042] Transmission assembly 31;

[0043] Driving motor 32;

[0044] Static force sensor 33;

[0045] Dynamic force applying mechanism 4;

[0046] Dynamic force sensor 41;

[0047] Excitation vibrator 42;

[0048] Fixing member 421;

[0049] Shell 4211;

[0050] Fixed block 4212;

[0051] Permanent magnet 422;

[0052] The moving part 423;

[0053] The fixed ring 423a;

[0054] The exciting coil 424;

[0055] The power supply 425;

[0056] The first elastic sheet 426;

[0057] The fixed ring 4261;

[0058] The elastic sheet 4262;

[0059] The fixed groove 426a;

[0060] The fixed hole 426b;

[0061] The connecting part 427;

[0062] The magnetic core 428;

[0063] The second elastic sheet 429. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below in combination with the drawings and examples. It should be understood that the specific examples described herein are only used to explain the present application and do not limit the present application.

[0065] In order to solve the technical problem that the piezoelectric constant of the piezoelectric ceramic is not accurate by referring to the sample sheet in the prior art, the present application provides a piezoelectric material piezoelectric constant measuring device, which can measure the piezoelectric constant of the piezoelectric material in real time and accurately.

[0066] It should be noted that the piezoelectric material piezoelectric constant measuring device described in the present application is used for but not limited to the measurement of the piezoelectric constant of the piezoelectric ceramic, etc. In order to facilitate the description, in the present application, only the piezoelectric material piezoelectric constant measuring device is applied to the measurement of the piezoelectric constant of the piezoelectric ceramic as an example for description, and the principle of the piezoelectric material piezoelectric constant measuring device applied to the measurement of other types of materials is the same as the measurement principle of the piezoelectric ceramic, which is not described here.

[0067] Please refer to Figure 1 shown, Figure 1As a structural schematic view of the piezoelectric constant measuring device for piezoelectric material in an embodiment of the present application, the piezoelectric constant measuring device for piezoelectric material comprises a body 1, a measuring mechanism 2, a static force applying mechanism 3 and a dynamic force applying mechanism 4. The measuring mechanism 2 comprises a first conductive part 21, a second conductive part 22 and a measuring assembly 23. The first conductive part 21 is arranged apart from the second conductive part 22. The measuring assembly 23 is electrically connected with the first conductive part 21 and the second conductive part 22, and is used for measuring the amount of electric charge released by the piezoelectric material when it is pressed. The static force applying mechanism 3 is connected with the first conductive part 21 and the body 1, and is used for applying a static force to the piezoelectric material through the first conductive part 21. The dynamic force applying mechanism 4 comprises a dynamic force sensor 41 and an exciter 42. The exciter 42 is connected with the body 1 and the dynamic force sensor 41, and is connected with the second conductive part 22 through the dynamic force sensor 41, and is used for applying a dynamic force to the piezoelectric material.

[0068] Specifically, when measuring the piezoelectric constant of the piezoelectric ceramic, the piezoelectric material is arranged between the first conductive part 21 and the second conductive part 22. The static force applying mechanism 3 is used for applying a static force to the piezoelectric ceramic. Then the dynamic force applying mechanism 4 is used for applying a dynamic force with varying size to the piezoelectric material.

[0069] The piezoelectric constant measuring formula of the piezoelectric ceramic is as follows:

[0070] D33=Q / F

[0071] In the formula, Q is the amount of electric charge released by the sample, and F is a low-frequency alternating vibration force applied to both ends of the sample.

[0072] The dynamic force F borne by the piezoelectric ceramic is detected by the dynamic force sensor 41, and the amount of electric charge Q released by the piezoelectric ceramic when it is pressed is detected by the measuring assembly 23. Thus, the actual piezoelectric constant of the piezoelectric material can be obtained. The influence of the pressure change caused by human factors on the value of D33 is effectively eliminated, and the influence of the error of the reference sample on the measurement accuracy of the piezoelectric ceramic is effectively eliminated.

[0073] In the embodiment, the body 1 can be a support mechanism formed by various structural combinations of various profiles, plates, standard parts and non-standard parts, etc.

[0074] In the embodiment, the measuring assembly 23 can be a data collector provided with a charge amplifier, a piezoelectric analyzer, etc.

[0075] It should be understood that the exciter 42 can be an electromagnetic exciter 42, an electric vibration table, etc. In one of the embodiments, as shown in Figure 4 Figure 5 and Figure 10 ​As shown, the exciter 42 comprises a fixed part 421, a permanent magnet 422, a movable part 423, an excitation coil 424 and a power supply 425. The fixed part 421 is connected to the fixed part 421. The permanent magnet 422 is connected to the fixed part 421. The movable part 423 is slidingly connected to the fixed part 421 and is connected to the dynamic force sensor 41 and the second conductive part 22 through the dynamic force sensor 41. The excitation coil 424 is connected to the movable part 423. The power supply 425 is electrically connected to the excitation coil 424 and is configured to output a driving electrical signal to the excitation coil 424 to drive the excitation coil 424 to drive the movable part 423 to apply a dynamic force to the piezoelectric material.

[0076] When it is necessary to apply a dynamic force to the piezoelectric ceramic through the dynamic force applying mechanism 4, the power supply 425 outputs an electrical signal to the excitation coil 424. The excitation coil 424 generates a magnetic field which interacts with the permanent magnet 422 to generate a magnetic force. The magnetic force drives the movable part 423 to move up and down, thereby achieving dynamic force application to the piezoelectric material. The dynamic force sensor 41 can detect the dynamic force applied to the piezoelectric ceramic and feed back to the power supply 425, forming a closed loop control to more accurately control the dynamic force applied to the piezoelectric ceramic.

[0077] In one embodiment, as shown in Figure 9 The measuring mechanism 2 further comprises a phase-locked loop module 24 which is electrically connected to the measuring assembly 23 and the dynamic force sensor 41. The phase-locked loop module 24 is configured to detect the phase of the force signal collected by the dynamic force sensor 41 and the phase of the charge signal collected by the measuring assembly 23. When the polarities of the phases of the force signal and the charge signal are the same, the front surface of the piezoelectric material is upward. When the polarities of the phases of the force signal and the charge signal are opposite, the back surface of the piezoelectric material is upward.

[0078] As shown in Figure 9 In one embodiment, the phase-locked loop module 24 is further electrically connected to the power supply 425 and is configured to detect the phase difference between the force signal and the charge signal in real time, lock the phase difference and output a phase adjustment signal to the control module of the power supply 425.

[0079] The dynamic force sensor 41 is responsible for collecting the force signal generated by the piezoelectric ceramic when it is under stress. The measuring assembly 23 is responsible for collecting the charge signal generated by the piezoelectric ceramic during deformation. The phase detector in the phase-locked loop module 24 compares the phases of the force signal and the charge signal. The phase detector uses an analog multiplier circuit to convert the phase difference into a voltage signal output. By comparing the phase polarities of the force signal and the charge signal, the orientation of the piezoelectric ceramic can be determined. When the phase polarities of the force signal and the charge signal are the same, it indicates that the front surface of the piezoelectric material is upward. When the phase polarities of the force signal and the charge signal are opposite, it indicates that the back surface of the piezoelectric material is upward.

[0080] In one of the embodiments, the power supply 425 can output electric signals of different sizes and different frequencies to the vibration coil 424, so as to adjust the frequency and size of the dynamic force output by the vibration coil 424.

[0081] By outputting electric signals of different frequencies to the vibration coil 424 by the power supply 425, the vibration coil 424 can form vibration forces of different frequencies, and the piezoelectric material is tested by the vibration forces of different frequencies; by outputting electric signals of different sizes to the vibration coil 424, the vibration coil 424 outputs dynamic forces of different sizes and amplitudes, and the test scene is increased and enriched.

[0082] It should be understood that the power supply 425 can be a power supply 425 regulated by PWM (pulse width modulation), or a power supply 425 changing the frequency of the output current by adjusting the capacitance, or a power supply 425 provided with a frequency converter to adjust the frequency and size of the output current.

[0083] It should be understood that the static force applying mechanism 3 can be a manually driven static force applying mechanism, or a static force applying mechanism driven by a motor, an air cylinder or a hydraulic cylinder. In one of the embodiments, as shown in Figure 8 the static force applying mechanism 3 includes a transmission assembly 31 connected to the first conductive part 21 and a driving motor 32 connected to the transmission assembly 31 and the body 1, which is used to connect the first conductive part 21 through the transmission assembly 31 to drive the first conductive part 21 to move linearly.

[0084] By providing the driving motor 32 and the transmission assembly 31, the driving motor 32 can drive the first conductive part 21 to move through the transmission assembly 31 and control the first conductive part 21 to output static force, without manually applying static force to the first conductive part 21, and by applying static force of different sizes, the piezoelectric constant of the piezoelectric ceramic under the action of different static forces can be measured.

[0085] It should be understood that the transmission assembly 31 can be a lead screw nut mechanism, or a gear and rack structure, etc. In one of the embodiments, as shown in Figure 8 the transmission assembly 31 is a lead screw nut mechanism, and the lead screw in the lead screw nut mechanism is connected to the output shaft of the driving motor 32 through a belt, and the nut is indirectly connected to the first conductive part 21.

[0086] In one of the embodiments, as shown in Figure 8 the static force applying mechanism 3 further includes a static force sensor 33, and the transmission assembly 31 is connected to the first conductive part 21 through the static force sensor 33, and the static force sensor 33 is used to measure the static force applied to the piezoelectric material.

[0087] The static force sensor 33 can detect and record the static force applied to the piezoelectric material in real time; these data can be transmitted to the external data processing part through the interface of the static force sensor 33 and stored.

[0088] In one embodiment, as shown in Figure 5 The dynamic force applying mechanism 4 further comprises at least one first elastic sheet 426 connected between the fixed part 421 and the movable part 423, for providing elastic force for resetting the movable part 423 after movement.

[0089] By setting the first elastic sheet 426, when the dynamic force is output by the excitation coil 424, the excitation coil 424 drives the movable part 423 to move, and the movable part 423 drives the first elastic sheet 426 to deform. The deformed first elastic sheet 426 has elastic force for resetting the moved movable part 423. The existence of the first elastic sheet 426 can quickly respond to the dynamic change of the excitation coil 424, help the excitation coil 424 and the movable part 423 quickly return to the initial position or the predetermined working state. This quick response helps to reduce the delay time of the system and improve the overall working efficiency of the exciter 42. The use of the first elastic sheet 426 can reduce the energy loss and performance decline caused by mechanical friction and wear, prolong the service life and reliability of the mechanism. The first elastic sheet 426 as an elastic element, its mechanical properties can be flexibly adjusted and optimized according to actual needs, so that the dynamic force applying mechanism 4 can adapt to different working scenes and load requirements.

[0090] It should be understood that the material of the first elastic sheet 426 can be spring steel, thin steel sheet, etc.

[0091] It should be understood that the number of the first elastic sheet 426 can be one, two, three, etc. In one embodiment, as shown in Figure 5 The number of the first elastic sheet 426 is two, and the two first elastic sheets 426 are arranged at the two ends of the movable part 423 along the sliding direction.

[0092] By setting two elastic sheets, both of them can limit the sliding of the movable part 423, avoiding the deflection of the sliding direction during the sliding of the movable part 423.

[0093] In one embodiment, as shown in Figure 6 and Figure 7As shown, the first elastic sheet 426 comprises a fixing ring 4261 and two elastic sheets 4262, the fixing ring 4261 is sleeved on the movable element 423, the two elastic sheets 4262 are respectively arranged on the two sides of the fixing ring 4261, and the two ends of the elastic sheet 4262 are connected with the fixing ring 4261; the dynamic force applying mechanism 4 further comprises at least two connecting parts 427, the at least two connecting parts 427 are connected with the fixing element 421 and respectively connected with one side of the two elastic sheets 4262.

[0094] The fixing ring 4261 is sleeved on the movable element 423, plays a role of fixing and supporting, and enables the elastic sheet to stably deform along with the movement of the movable element 423; through the fixing ring 4261 and the elastic sheet 4262 connected with each other and the elastic sheet 4262 connected with the movable element 423, the connection between the movable element 423 and the fixing element 421 is realized, through arranging the elastic sheet 4262 on the two sides of the movable element 423, when the movable element 423 moves, the elastic sheet 4262 on the two sides can provide elastic support and guidance for the movable movable element 423; since one side of the elastic sheet 4262 is fixed on the fixing element 421 by the connecting part 427, when the movable element 423 drives the fixing ring 4261 to move, the fixing ring 4261 drives the elastic sheet 4262 to move, so that the elastic sheet 4262 deforms, has a restoring elastic force, and the deformed elastic sheet 4262 can push the movable element 423 to reset.

[0095] It should be understood that the connecting part 427 can be a bolt, a screw, a buckle or the like.

[0096] In one of the embodiments, as shown in Figure 7 The end of the elastic sheet 4262 gradually increases in size along the direction close to the fixing ring 4261, the two elastic sheets 4262 are symmetrically arranged on the two sides of the fixing ring 4261, the ends of the two elastic sheets 4262 and the fixing ring 4261 jointly form a fixing groove 426a and a fixing hole 426b, the fixing groove 426a gradually decreases in size along the direction close to the fixing ring 4261, the fixing hole 426b is in communication with the fixing groove 426a, and the size of the communication part of the fixing hole 426b and the fixing groove 426a is smaller than the diameter of the fixing hole 426b.

[0097] By setting the end of the elastic sheet 4262 to gradually increase in size in the direction close to the fixed ring 4261, the connection strength of the connection between the elastic sheet 4262 and the fixed ring 4261 can be enhanced, and fatigue failure of the connection between the elastic sheet 4262 and the fixed ring 4261 can be avoided; by setting the fixed groove 426a, the fixed groove 426a gradually increases in size in the direction away from the fixed ring 4261, so that when the elastic sheet 4262 is stretched by the fixed ring 4261, the stress position deviates to both sides of the fixed ring 4261, and the two elastic sheets 4262 are symmetrically arranged on both sides of the fixed ring 4261, so that the elastic force symmetrically appears on both sides of the fixed ring 4261, and the elastic force on both sides deviates from the central symmetry line, which can provide stable support and reset elastic force for the movement of the fixed ring 4261, so that the movable part 423 only slides relative to the fixed part 421; by setting the fixed hole 426b, under the condition that the elastic sheet 4262 gradually increases in size in the direction close to the fixed ring 4261, the size of the end of the elastic sheet can be extended, and the size of the root of the elastic sheet 4262 can be reduced, which is beneficial to control the position of the deformation of the elastic sheet 4262 when driven by the fixed ring 4261, so that the deformation position of the elastic sheet 4262 is controlled at the end of the elastic sheet 4262.

[0098] In one embodiment, as shown in Figure 5 and Figure 10 The dynamic force applying mechanism 4 further includes a magnetic guide core 428 connected to the permanent magnet 422, the movable part 423 is sleeved on the magnetic guide core 428, and the number of the vibration coils 424 is two, and the two vibration coils 424 are distributed along the sliding direction of the movable part 423.

[0099] By connecting the magnetic guide core 428 with the permanent magnet 422, the magnetic field is guided and enhanced. The magnetic field acting on the vibration coil 424 is enhanced, and the magnetic field is uniformly distributed in the mechanism, thereby improving the effect between the magnetic field and the vibration coil 424; the movable part 423 is sleeved on the magnetic guide core 428, which enables the movable part 423 to slide stably and accurately under the guidance of the magnetic guide core 428; by distributing the two vibration coils 424 along the sliding direction of the movable part 423, the two vibration coils 424 jointly form a dynamic force with the magnetic field of the permanent magnet 422 when energized, and the dynamic force formed by the two vibration coils 424 acts on both ends of the sliding direction of the movable part 423, so that the movable part 423 can quickly respond on the basis of being sleeved on the magnetic guide core 428, and the stress direction of the vibration coil 424 applied to the movable part 423 deviates from the axis, so that the dynamic force applying mechanism 4 can more accurately control the movement of the movable part 423.

[0100] Since the moving part 423 is connected to the vibration coil 424, the second conductive part 22 and the dynamic force sensor 41, the gravity of the vibration coil 424, the second conductive part 22 and the dynamic force sensor 41 all acts on the moving part 423. When the vibration coil 424 is energized to drive the moving part 423 to move, the gravity of the vibration coil 424, the second conductive part 22 and the dynamic force sensor 41 needs to be overcome first, and then the moving part 423 can output dynamic force outward, which reduces the sensitivity and response speed of the moving part 423 to output dynamic force. Therefore, in one of the embodiments, as shown in Figure 4 the dynamic force applying mechanism 4 further comprises a second elastic sheet 429 connected to the second conductive part 22 and the fixed part 421, and the rigidity of the second elastic sheet 429 is greater than that of the first elastic sheet 426. The dynamic force sensor 41 is connected to the second elastic sheet 429, and the second conductive part 22 is connected through the second elastic sheet 429.

[0101] By arranging the second elastic sheet 429, the second elastic sheet 429 is connected to the fixed part 421 and the second conductive part 22, and the dynamic force sensor 41, the moving part 423 and the vibration coil 424 are connected through the second conductive part 22. The second elastic sheet 429 can offset and bear the gravity of the second conductive part 22, the dynamic force sensor 41, the moving part 423 and the vibration coil 424, so that when the vibration coil 424 is energized to form dynamic force, the moving part 423, the dynamic force sensor 41 and the second conductive part 22 can be quickly driven to move, and the sensitivity and response speed of the moving part 423 and the second conductive part 22 to output dynamic force can be increased. Secondly, by setting the rigidity of the second elastic sheet 429 to be greater than that of the first elastic sheet 426, or causing the support effect of the second elastic sheet 429 to be less than that of the first elastic sheet 426. Therefore, in this embodiment, the rigidity of the second elastic sheet 429 is set to be greater than that of the first elastic sheet 426, so as to distinguish the effects of the second elastic sheet 429 and the first elastic sheet 426. The elastic force of the second elastic sheet 429 realizes the balance between the gravity of the second conductive part 22, the dynamic force sensor 41, the moving part 423 and the vibration coil 424, while the first elastic sheet 426 plays a role in quickly resetting the moving part 423 after movement. The two work together to enhance the response speed and sensitivity of the second conductive part 22 to output dynamic force.

[0102] It should be understood that the fixed part 421 can be various housings 4211, supports and the like that can play a fixing role. In one of the embodiments, as shown in Figure 5As shown, the fixing member 421 comprises a shell 4211 and an annular fixing block 4212, the shell 4211 is hollow inside, a through hole is formed in the top of the shell 4211, the shell 4211 is connected to the machine body 1 and is sleeved on the second conductive part 22 through the through hole; the dynamic force sensor 41, the movable member 423 and the permanent magnet 422 are sequentially arranged in the shell 4211 in the vertical direction, the fixing block 4212 is arranged in the shell 4211 and is sleeved on the movable member 423, two first elastic sheets 426 are connected to the fixing block 4212 through the connecting part 427 and are arranged at both ends of the fixing block 4212, the vibration exciter 42 further comprises two fixing rings 423a, the two fixing rings 423a are arranged at both ends of the fixing block 4212 and are arranged on the side opposite to the two first elastic sheets 426, for fixing the first elastic sheets 426 to the movable member 423.

[0103] It should be understood that the fixing ring 423a and the movable member 423 can be fixedly connected, can be threadedly connected, and can be connected through a bolt, a screw or a buckle.

[0104] In one of the embodiments, as shown in Figure 2 and Figure 3 The first conductive part 21 and the second conductive part 22 are coaxial, and the opposite ends are in a ball head shape.

[0105] It should be understood that the first conductive part 21 and the second conductive part 22 can be an electrode, a conductive column and a conductive block.

[0106] By coaxially arranging the first conductive part 21 and the second conductive part 22 and setting the opposite ends of the first conductive part 21 and the second conductive part 22 in a ball head shape, the contact between the first conductive part 21 and the second conductive part 22 and the piezoelectric ceramic is point contact, the two points of the point contact are in a straight line, the straight line is coaxial with the first conductive part 21 and the second conductive part 22, the direction of the pressure is parallel to the polarization axis of the piezoelectric ceramic, by the point contact between the first conductive part 21 and the second conductive part 22 and the piezoelectric ceramic, the sample deformation is small, and each measurement point is more uniform.

[0107] The specific embodiments of the application described above do not constitute a limitation on the protection scope of the application. Any various other corresponding changes and modifications made according to the technical concept of the application should be included in the protection scope of the claims of the application.

Claims

1. A piezoelectric material piezoelectric constant measuring device characterized by comprising: The device comprises: a body; a measuring mechanism, which comprises a first conductive part, a second conductive part and a measuring component, the first conductive part is spaced apart from the second conductive part, the measuring component is electrically connected with the first conductive part and the second conductive part, and is used for measuring the amount of charge released by the piezoelectric material when it is pressed; a static force applying mechanism, which is connected with the first conductive part and the body, and is used for applying a static force to the piezoelectric material through the first conductive part; and a dynamic force applying mechanism, which comprises a dynamic force sensor and a vibration exciter, the vibration exciter is connected with the body and the dynamic force sensor, and is connected with the second conductive part through the dynamic force sensor, and is used for applying a dynamic force to the piezoelectric material; the vibration exciter comprises a fixed part, a permanent magnet, a movable part, a vibration coil and a power supply, the fixed part is connected with the fixed part, the permanent magnet is connected with the fixed part, the movable part is slidingly connected with the fixed part, and the movable part is connected with the dynamic force sensor and the second conductive part through the dynamic force sensor, the vibration coil is connected with the movable part, and the power supply is electrically connected with the vibration coil, and is used for outputting a driving electric signal to the vibration coil to drive the vibration coil to drive the movable part to apply a dynamic force to the piezoelectric material; the dynamic force applying mechanism further comprises at least one first elastic sheet, the first elastic sheet is connected with the fixed part and the movable part, and is used for providing an elastic force for resetting the movable part after the movable part is moved; the first elastic sheet comprises a fixed ring and two elastic sheets, the fixed ring is sleeved on the movable part, the two elastic sheets are respectively arranged on the two sides of the fixed ring, and the two ends of the elastic sheet are connected with the fixed ring; the end of the elastic sheet gradually increases in size along the direction close to the fixed ring, the two elastic sheets are symmetrically arranged on the two sides of the fixed ring, the ends of the two elastic sheets and the fixed ring form a fixed groove and a fixed hole, the fixed groove gradually decreases in size along the direction close to the fixed ring, the fixed hole is in communication with the fixed groove, and the size of the communication part of the fixed hole and the fixed groove is smaller than the diameter of the fixed hole.

2. The piezoelectric constant measuring device for piezoelectric material according to claim 1, wherein: the measuring mechanism further comprises a phase-locked loop module, the phase-locked loop module is electrically connected with the measuring component and the dynamic force sensor, and is used for detecting the phase of the force signal collected by the dynamic force sensor and the phase of the charge signal collected by the measuring component; when the polarities of the phases of the force signal and the charge signal are the same, at this time, the piezoelectric material is front-up; when the polarities of the phases of the force signal and the charge signal are opposite, at this time, the piezoelectric material is back-up.

3. The piezoelectric constant measuring device for piezoelectric material according to claim 2, wherein: the phase-locked loop module is further electrically connected with the power supply, and is further used for detecting the phase difference between the force signal and the charge signal in real time, locking the phase difference, and outputting a phase adjustment signal to the control module of the power supply.

4. The piezoelectric constant measuring device for piezoelectric material according to claim 1, wherein, The power supply can output electric signals of different sizes and different frequencies to the exciting coil, so as to adjust the frequency and size of the dynamic force output by the exciting coil. 5.The piezoelectric material piezoelectric constant measuring device according to claim 1, wherein, The static force applying mechanism comprises a transmission assembly and a driving motor, the transmission assembly is connected to the first conductive part, and the driving motor is connected to the transmission assembly and the machine body, and is used for driving the first conductive part to move linearly through the transmission assembly.

6. The piezoelectric material piezoelectric constant measuring apparatus according to claim 5, wherein The static force applying mechanism further comprises a static force sensor, the transmission assembly is connected to the first conductive part through the static force sensor, and the static force sensor is used for measuring the static force applied to the piezoelectric material. 7.The piezoelectric material piezoelectric constant measuring device according to claim 1, wherein, The dynamic force applying mechanism further comprises a second elastic sheet, the second elastic sheet is connected to the second conductive part and the fixing part, the rigidity of the second elastic sheet is greater than that of the first elastic sheet, the dynamic force sensor is connected to the second elastic sheet, and the second elastic sheet is connected to the second conductive part. 8.The piezoelectric material piezoelectric constant measuring device according to claim 1, wherein, The first conductive part and the second conductive part are coaxial, and the opposite ends thereof are in spherical head shape.

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