Acceleration sensor

Abstract

The utility model belongs to the technical field of sensors, and particularly relates to an acceleration sensor, which comprises a shell, a piezoelectric component, an integrated amplification module and a signal interface, and is characterized in that the shell comprises a base and an assembly cavity, and the center of the base is fixedly connected with the piezoelectric component; the base is fixed on the to-be-measured object, and the piezoelectric assembly is fixed at the center of the base, so that the to-be-measured object can be directly and accurately monitored, and the influence of deformation of the middle structure on monitoring is avoided. The piezoelectric assembly comprises a stud, the stud and the base are integrally formed, the stud is sequentially sleeved with a first mass block, a piezoelectric element, a second mass block and a locking nut, and the piezoelectric element is in circuit connection with the integrated amplification module; the first mass block and the second mass block are fixed to the two sides of the piezoelectric element through cooperation of the locking nut and the stud, one mass block can extrude the piezoelectric element through acceleration movement in any direction of the axis of the stud, monitoring of the piezoelectric element is facilitated, the structure is reasonable, interference of an amplifier circuit can be reduced, and the reliability of the piezoelectric element is improved. And rapid assembly is facilitated.

Description

Technical Field

[0001] The utility model belongs to the technical field of sensors, and particularly relates to an acceleration sensor. Background Art

[0002] IEPE (Integrated Electronics Piezo-Electric) acceleration sensor, that is, piezoelectric integrated circuit acceleration sensor, is an acceleration sensor with a built-in charge amplifier or voltage amplifier.

[0003] The working principle of the IEPE acceleration sensor is mainly based on the piezoelectric effect. When the piezoelectric crystals inside the sensor are subjected to the acceleration caused by external vibration, they will generate charges, and then generate a voltage signal. This voltage signal is proportional to the acceleration of the vibration, so the acceleration of the vibration can be indirectly measured by measuring the voltage signal.

[0004] Since the charge generated by the acceleration sensor is very small and is easily affected by noise interference, sensitive electronic devices are integrated inside the IEPE acceleration sensor. The piezoelectric transducer in the sensor part converts the mechanical vibration signal into a charge signal, and the charge signal is input into the junction field effect transistor (JEFT) module. The JEFT module amplifies the charge signal and converts it into a voltage signal to ensure the stability and accuracy of the signal. The IEPE acceleration sensor has the advantages of high sensitivity, good stability, easy operation, etc., so it is widely used in mechanical equipment, aerospace engineering, building structure monitoring, earthquake monitoring, etc.

[0005] The principle of the IEPE acceleration sensor is that the piezoelectric crystal generates charges due to external pressure deformation and then generates a voltage signal. It mainly consists of a voltage amplifier circuit, a piezoelectric component and a housing. The existing small IEPE acceleration sensor parts are modularly designed. Due to the unreasonable highly integrated layout, the piezoelectric component is easily interfered by the voltage amplifier circuit, and the sensor is inconvenient to install. Content of the Utility Model

[0006] The purpose of the utility model is to provide an acceleration sensor with a reasonable structure, which can not only reduce the interference of the amplifier circuit, but also facilitate rapid assembly.

[0007] To achieve the above technical purpose, the technical scheme adopted by the utility model is as follows:

[0008] An acceleration sensor includes a housing, a piezoelectric component, an integrated amplification module and a signal interface. The housing includes a base and an assembly cavity. The center of the base is fixedly connected with the piezoelectric component; the base is fixed on the object to be measured, and the piezoelectric component is fixed at the center of the base, which can directly and accurately monitor the object to be measured and avoid the influence of the deformation of the intermediate structure on the monitoring.

[0009] The piezoelectric component includes a stud, which is integrally formed with the base. The studs are successively sleeved with a first mass block, a piezoelectric element, a second mass block, and a locking nut. The first mass block, the piezoelectric element, the second mass block, and the locking nut are all suspended. The first mass block and the second mass block have the same shape and mass. The piezoelectric element is circuit-connected to the integrated amplification module. The first mass block and the second mass block are fixed on both sides of the piezoelectric element through the cooperation of the locking nut and the stud. When accelerating in any direction along the axis of the stud, one of the mass blocks can squeeze the piezoelectric element, facilitating the monitoring of the piezoelectric element.

[0010] The assembly cavity includes a first installation cavity, a shielding plate, and a second installation cavity for fixing the integrated amplification module. The opening of the first installation cavity matches the base, and the opening of the second installation cavity matches the signal interface. A wire passing hole is provided in the center of the shielding plate. The piezoelectric element and the integrated amplification module are electrically connected through the wire passing hole. One end of the signal interface is electrically connected to the integrated amplification module. The assembly cavity is provided with two cavities, the first installation cavity and the second installation cavity, and is isolated by the shielding plate, which can avoid the signal of the integrated amplification module interfering with the piezoelectric element. The integrated amplification module is fixed in the second installation cavity, and the circuit is easy to install and connect through the wire passing hole.

[0011] The shielding plate is provided with threaded studs, and the integrated amplification module is provided with through holes matching the threaded studs. The threaded studs pass through the through holes and are connected with nuts.

[0012] The diameters of the first installation cavity and the second installation cavity are different.

[0013] The rear part of the base is provided with internal threads, and a protective cover is threadedly connected to the internal threads.

[0014] The base is provided with a first installation boss matching the opening of the first installation cavity, and the second installation cavity is provided with a second installation boss matching the signal interface.

[0015] The structure of the utility model is reasonable, which can not only reduce the interference of the amplifier circuit but also facilitate rapid assembly. Brief Description of the Drawings

[0016] The utility model can be further illustrated by the non-limiting embodiments given in the drawings;

[0017] Figure 1 is a schematic structural view of an acceleration sensor of the utility model Figure 1 ;

[0018] Figure 2 is a schematic structural view of an acceleration sensor of the utility model Figure 2 ;

[0019] Figure 3Schematic cross-sectional structure diagram of an acceleration sensor of the present utility model;

[0020] Descriptions of main component symbols are as follows:

[0021] Housing 1, base 11, internal thread 111, protective cover 112, first mounting boss 113, assembly cavity 12, first mounting cavity 121, shielding plate 122, wire passing hole 1221, threaded post 1222, second mounting cavity 123, second mounting boss 1231, piezoelectric component 2, stud 21, first mass block 22, piezoelectric element 23, second mass block 24, locking nut 25, integrated amplification module 3, signal interface 4 Specific embodiments

[0022] In order to enable those skilled in the art to better understand the present utility model, the technical solution of the present utility model will be further described below in conjunction with the drawings and embodiments.

[0023] As Figures 1-3 shown, an acceleration sensor of the present utility model includes a housing 1, a piezoelectric component 2, an integrated amplification module 3, and a signal interface 4. The housing 1 includes a base 11 and an assembly cavity 12, and the center of the base 11 is fixedly connected to the piezoelectric component 2.

[0024] The connection and working principle of the piezoelectric component 2, the integrated amplification module 3, and the signal interface 4 belong to the prior art and will not be described in detail here. The housing 1 is split into a base 11 and an assembly cavity 12 for convenient installation of components. The base 11 is fixed on the object to be measured, and the piezoelectric component 2 is fixed at the center of the base 11, which can directly and accurately monitor the object to be measured, reduce the intermediate structure, and avoid the influence of other deformations on the monitoring. The outside of the base 11 is hexagonal, which is convenient for using tools to apply force during installation.

[0025] The piezoelectric component 2 includes a stud 21, which is integrally formed with the base 11. The stud 21 is sequentially sleeved with a first mass block 22, a piezoelectric element 23, a second mass block 24, and a locking nut 25. The first mass block 22, the piezoelectric element 23, the second mass block 24, and the locking nut 25 are all suspended. The first mass block 22 and the second mass block 24 have the same shape and mass, and the piezoelectric element 23 is electrically connected to the integrated amplification module 3.

[0026] The stud 21 is integrally formed with the base 11, reducing assembly and deformation interference. The first mass block 22 and the second mass block 24 are fixed on both sides of the piezoelectric element 23 through the cooperation of the locking nut 25 and the stud 21. Any acceleration movement along the axis of the stud 21 can cause one of the mass blocks to squeeze the piezoelectric element 23, facilitating the monitoring of the piezoelectric element 23.

[0027] The assembly cavity 12 includes a first mounting cavity 121, a shielding plate 122, and a second mounting cavity 123 for fixing the integrated amplifier module 3. The opening of the first mounting cavity 121 matches the base 11, and the opening of the second mounting cavity 123 matches the signal interface 4. A wire passing hole 1221 is provided at the center of the shielding plate 122. The piezoelectric element 23 and the integrated amplifier module 3 are electrically connected by wires through the wire passing hole 1221. One end of the signal interface 4 is electrically connected to the integrated amplifier module 3.

[0028] The first mounting cavity 121 and the base 11 cooperate to seal and wrap the piezoelectric assembly 2 for protection and interference reduction. The integrated amplifier module 3 is independently placed in the second mounting cavity 123, and the second mounting cavity 123 is closed by the signal interface 4. In this way, during assembly, it can be first assembled in three parts, namely the housing 1 and the piezoelectric assembly 2, the integrated amplifier module 3 and the assembly cavity 12, and the signal interface 4. After the three parts are classified and produced, the piezoelectric element 23, the integrated amplifier module 3, and the signal interface 4 are respectively connected by circuit welding, and finally, unified glue encapsulation is carried out. Such modular production and processing can improve the assembly efficiency and production capacity.

[0029] The shielding plate 122 is provided with threaded posts 1222, and the integrated amplifier module 3 is provided with through holes matching the threaded posts 1222. The threaded posts 1222 pass through the through holes and are connected with nuts. Using the threaded posts 1222 not only raises the integrated amplifier module 3 to help with heat dissipation, but also insulating posts can be added to prevent electric leakage.

[0030] The diameters of the first mounting cavity 121 and the second mounting cavity 123 are different. This can quickly distinguish the first mounting cavity 121 and the second mounting cavity 123 and improve the assembly efficiency.

[0031] The rear part of the base 11 is provided with an internal thread 111, and a protective cover 112 is threadedly connected to the internal thread 111. The internal thread 111 facilitates the installation of the acceleration sensor. The protective cover 112 protects the thread of the internal thread 111 when the acceleration sensor is not installed, and the protective cover 112 is provided with a handle for easy disassembly.

[0032] The base 11 is provided with a first mounting boss 113 matching the opening of the first mounting cavity 121, and the second mounting cavity 123 is provided with a second mounting boss 1231 matching the signal interface 4. The first mounting boss 113 and the second mounting boss 1231 not only facilitate positioning but also provide a platform for glue bonding.

[0033] The structure of the present utility model is reasonable, which can not only reduce the interference of the amplifier circuit but also facilitate rapid assembly.

[0034] The above embodiments are only used to exemplarily illustrate the principles and effects of the present utility model, rather than to limit the present utility model. Any person familiar with this technology can modify or change the above embodiments without departing from the spirit and scope of the present utility model. Therefore, all equivalent modifications or changes completed by those with ordinary knowledge in the technical field without departing from the spirit and technical idea disclosed by the present utility model should still be covered by the claims of the present utility model.

Claims

1. An acceleration sensor, comprising a housing (1), a piezoelectric component (2), an integrated amplification module (3) and a signal interface (4), characterized in that: The housing (1) comprises a base (11) and an assembly cavity (12), and the center of the base (11) is fixedly connected to the piezoelectric component (2); The piezoelectric component (2) comprises a stud (21), the stud (21) and the base (11) are integrally formed, the stud (21) is sequentially sleeved with a first mass block (22), a piezoelectric element (23), a second mass block (24) and a locking nut (25), the first mass block (22), the piezoelectric element (23), the second mass block (24) and the locking nut (25) are all suspended in the air, the first mass block (22) and the second mass block (24) have the same shape and mass, and the piezoelectric element (23) is connected to the circuit of the integrated amplifier module (3); The assembly cavity (12) comprises a first installation cavity (121), a shielding plate (122) and a second installation cavity (123) for fixing the integrated amplifier module (3); the opening of the first installation cavity (121) matches the base (11); the opening of the second installation cavity (123) matches the signal interface (4); a wire hole (1221) is provided at the center of the shielding plate (122); the piezoelectric element (23) is connected to the integrated amplifier module (3) by wires through the wire hole (1221); and one end of the signal interface (4) is electrically connected to the integrated amplifier module (3).

2. An acceleration sensor according to claim 1, characterized in that: The shielding plate (122) is provided with a threaded column (1222), the integrated amplification module (3) is provided with a through hole matching the threaded column (1222), and the threaded column (1222) passes through the through hole and is connected with a nut.

3. An acceleration sensor according to claim 1, characterized in that: The diameters of the first installation cavity (121) and the second installation cavity (123) are different.

4. The acceleration sensor according to claim 1, characterized in that: The rear portion of the base (11) is provided with an internal thread (111), and the internal thread (111) is threadedly connected to a protective cover (112).

5. The acceleration sensor according to claim 1, characterized in that: The base (11) is provided with a first mounting boss (113) matching with the opening of the first mounting cavity (121), and the second mounting cavity (123) is provided with a second mounting boss (1231) matching with the signal interface (4).

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