A composite sensor

Abstract

This application discloses a composite sensor, relating to the field of mechanical detection sensor technology, aiming to solve the problems that a single sensor cannot simultaneously meet the needs of dynamic and static force measurement, and that traditional spliced ​​composite sensors have low integration and compromised accuracy. The sensor includes a piezoelectric sensing unit, a resistance sensing unit, double-sided adhesive tape, and an outer encapsulation layer. The piezoelectric sensing unit comprises a piezoelectric positive electrode, a piezoelectric material, and a piezoelectric negative electrode stacked sequentially, and a piezoelectric terminal electrically connected to the piezoelectric negative electrode is provided via the terminal support tape. The resistance sensing unit comprises a resistive material, a resistive electrode, and a PET sheet stacked sequentially, with a piezoresistive terminal electrically connected to the resistive electrode on the surface of the PET sheet. The insulating double-sided adhesive tape is sandwiched between the piezoelectric positive electrode and the resistive material, bonding them together to form an integrated structure. Through this integrated stacked design, the sensor can simultaneously and accurately detect dynamic forces (such as vibration and impact) and static forces (such as constant pressure).

Description

Technical Field

[0001] This application relates to the field of mechanical detection sensor technology, and in particular to a composite sensor. Background Technology

[0002] In the current field of sensor technology, piezoelectric sensors and resistive sensors are two widely used mainstream sensing devices. They sense external physical quantities based on different working principles and play important roles in their respective applicable scenarios. The core working mechanism of piezoelectric sensors relies on the piezoelectric effect of piezoelectric materials—when a piezoelectric material is subjected to external dynamic forces (such as vibration, impact, instantaneous pressure, etc.), polarization occurs within it, generating a detectable electrical signal, thus converting mechanical energy into electrical energy. Due to this characteristic, piezoelectric sensors have significant advantages in terms of fast response speed and high sensitivity. Therefore, they are widely used in fields with high real-time signal requirements, such as dynamic force measurement, vibration monitoring, and acoustic detection, including scenarios like automotive engine vibration monitoring and industrial equipment fault diagnosis.

[0003] Resistive sensors achieve their sensing function based on the resistance-strain effect of conductive materials. When the sensor is subjected to an external static or quasi-static force (such as constant pressure or slow deformation), the resistance of its internal resistive material changes with stress or strain. By detecting this change in resistance, the magnitude of the external force can be deduced. These sensors are characterized by their simple structure, mature manufacturing process, and low cost, and are widely used in scenarios such as static pressure measurement, weight detection, and structural deformation monitoring, including pressure sensing in electronic scales and static stress monitoring in building structures.

[0004] However, with the rapid development of industries such as the Internet of Things, intelligent manufacturing, and high-end equipment monitoring, practical application scenarios have placed higher demands on the functional integration and comprehensive performance of sensors. In many complex working conditions, such as force feedback control of industrial robot end effectors (which requires simultaneous monitoring of instantaneous impact force and constant clamping force) and pressure detection of smart device buttons (which requires simultaneous recognition of rapid pressing dynamic signals and long-press static signals), relying on a single type of sensor is no longer sufficient. If a piezoelectric sensor is used alone, although it can efficiently capture dynamic signals, its measurement accuracy for static or quasi-static forces is extremely low, and it may even be unable to achieve effective detection. If a resistive sensor is used alone, although it can accurately measure static forces, its dynamic response speed is slow, making it difficult to capture instantaneously changing force signals in real time.

[0005] To address this issue, existing technologies have attempted to combine independently packaged piezoelectric sensors with resistive sensors through mechanical splicing, aiming to simultaneously achieve dynamic and static measurement capabilities. However, this approach has significant drawbacks: firstly, the two separate packaging processes result in a large overall structure with low integration, making it difficult to adapt to the installation requirements of miniaturized and lightweight equipment; secondly, the mechanical splicing method increases the number of parts and assembly steps, not only raising manufacturing costs but also potentially affecting measurement accuracy and structural stability due to issues such as splicing gaps and relative displacement between components, failing to meet the comprehensive requirements of "miniaturization, low cost, high integration, and high precision" for sensors under complex working conditions.

[0006] In summary, the current sensor technology field urgently needs a new composite sensor structure that can effectively integrate the advantages of piezoelectric sensors and resistive sensors, while avoiding the defects of using them alone and traditional splicing schemes, and achieving both high dynamic response and high static accuracy. Utility Model Content

[0007] To overcome the aforementioned technical problems, this application provides a composite sensor.

[0008] A composite sensor includes a piezoelectric sensing unit, a resistance sensing unit, double-sided tape, and an outer encapsulation layer; the piezoelectric sensing unit includes a piezoelectric positive electrode, the resistance sensing unit includes a resistive material, the double-sided tape is sandwiched between the piezoelectric positive electrode and the resistive material and bonds the two together, and the outer encapsulation layer encapsulates the piezoelectric sensing unit and the resistance sensing unit into an integrated structure.

[0009] By adopting the above technical solution, the piezoelectric sensing unit and the resistance sensing unit are bonded together with double-sided adhesive tape, and the outer encapsulation layer encapsulates the piezoelectric sensing unit and the resistance sensing unit into an integrated structure, which can replace the traditional mechanical splicing method, eliminate the risk of splicing gaps and relative displacement of components, greatly improve the overall integration of the sensor, and lay the structural foundation for the independent acquisition of the two types of sensing signals in the future.

[0010] Preferably, the resistance sensing unit further includes a resistance electrode, which is stacked on the side of the resistive material opposite to the double-sided tape and is laminated and bonded to the resistive material.

[0011] By adopting the above technical solution, the resistive electrode and the resistive material form a tight laminated structure, which can directly receive the resistance change signal generated by the resistive material under force, reduce signal loss during transmission, ensure the accuracy of resistance signal acquisition during static force measurement, and provide a reliable signal source for the accurate back-calculation of the magnitude of the static force.

[0012] Preferably, the resistance sensing unit further includes a PET sheet, which covers and encapsulates the side of the resistive electrode opposite to the resistive material, and is laminated and bonded to the resistive electrode.

[0013] By adopting the above technical solution, the PET sheet can provide physical protection for the resistive electrode, isolating it from damage caused by external dust and slight friction. On the other hand, it has a certain rigidity and force transmission, which can uniformly transmit the static force applied by the outside to the resistive material below, avoiding uneven resistance changes caused by local stress concentration, and further improving the stability of static measurement.

[0014] Preferably, the resistance sensing unit further includes at least one piezoresistive terminal, which is attached to the surface of the PET sheet and electrically connected to the resistive electrode.

[0015] By adopting the above technical solution, the piezoresistive terminal constructs a stable interface between the resistance sensing unit and the external signal processing circuit, enabling the static resistance signal collected by the resistance electrode to be directly and without interference transmitted to the external circuit. At the same time, the mating installation design simplifies the assembly process, reduces the number of parts, and lowers the overall manufacturing cost of the sensor.

[0016] Preferably, the piezoelectric sensing unit further includes a piezoelectric material and a piezoelectric negative electrode, wherein the piezoelectric material and the piezoelectric negative electrode are stacked sequentially on the side of the piezoelectric positive electrode away from the double-sided tape.

[0017] By adopting the above technical solution, the piezoelectric sensing unit forms a symmetrical stacked structure of piezoelectric positive electrode, piezoelectric material and piezoelectric negative electrode. When external dynamic force is applied, the piezoelectric material can uniformly generate polarized charge between the two electrodes, improve the generation efficiency and uniformity of dynamic charge signal, and ensure the high sensitivity detection of dynamic forces such as vibration and impact by the piezoelectric sensing unit.

[0018] Preferably, the piezoelectric sensing unit further includes at least one piezoelectric terminal, which is bonded to the piezoelectric negative electrode by a terminal support tape and electrically connected to the piezoelectric negative electrode.

[0019] By adopting the above technical solution, the terminal support tape can provide a stable installation position for the piezoelectric terminal, preventing it from shifting or falling off during sensor stress or vibration, ensuring the continuity and stability of the electrical connection between the piezoelectric terminal and the piezoelectric negative electrode, and thus ensuring the reliability of the transmission of dynamic charge signals to external circuits.

[0020] Preferably, the outer encapsulation layer covers the outer side of the PET sheet opposite to the resistive electrode and the outer side of the piezoelectric negative electrode opposite to the piezoelectric material.

[0021] By adopting the above technical solution, the outer encapsulation layer provides all-round protection for the core components inside the sensor (resistive electrodes, piezoelectric materials, terminals, etc.), effectively preventing moisture, dust and other impurities from entering the interior and causing component corrosion or short circuits; at the same time, it enhances the mechanical strength of the overall sensor structure, improves its impact and deformation resistance under complex working conditions, and extends its service life.

[0022] Preferably, the double-sided tape is an insulating material used to keep the resistive electrode and the piezoelectric positive electrode insulated.

[0023] By adopting the above technical solution, the insulation properties of double-sided tape can block the electrical conduction path between the dynamic charge signal on the piezoelectric positive electrode and the static resistance signal on the resistive electrode, completely avoiding mutual interference between the two types of signals. This ensures that the piezoelectric sensing unit can independently detect dynamic force and the resistive sensing unit can independently detect static force, greatly improving the accuracy of the two types of measurement data.

[0024] In summary, this application includes at least one of the following beneficial technical effects:

[0025] 1. Through an integrated stacked design, it has the ability to measure both dynamic force (vibration, impact) and static force (constant pressure), which makes up for the functional defects of a single sensor. It can be adapted to complex working conditions such as force feedback of industrial robots and button detection of smart devices, thus broadening the application scenarios of the sensor.

[0026] 2. By integrating double-sided tape bonding with the outer packaging layer, the traditional mechanical splicing scheme is replaced, reducing the number of independent packaging processes and parts, making the overall sensor smaller and lighter, meeting the requirements of miniaturized and lightweight installation of equipment, while reducing manufacturing costs and assembly difficulty.

[0027] 3. By utilizing the insulating properties of double-sided tape, the uniform force transmission of PET sheet, and the positioning function of terminal support tape, performance is optimized from three dimensions: signal isolation, force transmission, and structural stability. This effectively avoids problems such as signal interference, local stress error, and terminal displacement, thereby improving the sensor's measurement accuracy and long-term operational stability. Attached Figure Description

[0028] Figure 1 This is an exploded view of the sensor, mainly showing its specific structure.

[0029] Explanation of reference numerals in the attached drawings: 1. Terminal support tape; 11. Piezoelectric terminal; 2. Piezoelectric negative electrode; 3. Piezoelectric material; 4. Piezoelectric positive electrode; 5. Resistive material; 6. Resistive electrode; 7. PET sheet; 8. Piezoresistive terminal; 9. Double-sided tape; 10. Outer encapsulation layer; 100. Piezoelectric sensing unit; 200. Resistive sensing unit. Detailed Implementation

[0030] The present application will be further described in detail below with reference to the accompanying drawings.

[0031] This application discloses a composite sensor, referring to... Figure 1 The sensor integrates a piezoelectric sensing unit 100 and a resistance sensing unit 200 through an integrated stacked structure. The sensor mainly consists of the piezoelectric sensing unit 100, the resistance sensing unit 200, double-sided adhesive tape 9, and an outer encapsulation layer 10. The piezoelectric sensing unit 100 includes a piezoelectric positive electrode 4, a piezoelectric negative electrode 2, a piezoelectric material 3, a piezoelectric terminal 11, and a terminal support tape 1. The resistance sensing unit 200 includes a resistive material 5, a resistive electrode 6, a PET sheet 7, and a piezoresistive terminal 8. The outer encapsulation layer 10 encapsulates the piezoelectric sensing unit 100 and the resistance sensing unit 200 into a single integrated structure.

[0032] The double-sided tape 9 is made of insulating material and is sandwiched between the piezoelectric positive electrode 4 of the piezoelectric sensing unit 100 and the resistive material 5 of the resistance sensing unit 200. One side is firmly bonded to the resistive material 5, and the other side is firmly bonded to the piezoelectric positive electrode 4. Through physical bonding, the two originally independent sensing units are integrated into an inseparable structure, avoiding the gap and displacement problems caused by traditional mechanical splicing. The double-sided tape 9, relying on its own insulating properties, can effectively block the electrical conduction path between the piezoelectric positive electrode 4 and the resistive electrode 6, preventing the dynamic charge signal generated by the piezoelectric sensing unit 100 from interfering with the static resistance signal generated by the resistance sensing unit 200, thus providing a basic guarantee for the independent acquisition and transmission of the two types of signals.

[0033] The resistance sensing unit 200 is used for static or quasi-static force measurement and adopts a stacked structure. The resistive material 5 serves as the source of the static force signal, and is attached to the side of the resistance sensing unit 200 facing the double-sided tape 9. The resistive electrode 6 performs the function of collecting and transmitting the resistance signal, ensuring that the resistance change signal generated by the resistive material 5 can be transmitted to the electrode without loss. The PET sheet 7 is a protective and force transmission component of the resistance sensing unit 200, covering and encapsulating the resistive electrode 6 on the outside away from the resistive material 5, forming a wrap-around protection for the resistive electrode 6 and the resistive material 5. The piezoresistive terminal 8 is the interface for transmitting the resistance signal to external circuits, and is attached to a pre-set conductive window on the surface of the PET sheet 7 with conductive adhesive. It is used to interface with the signal processing circuit, ultimately forming a complete static signal transmission loop, allowing the resistance signal to be acquired and processed by subsequent signal circuits.

[0034] The piezoelectric sensing unit 100, used for measuring dynamic force, also adopts a stacked structure, arranged sequentially along the direction away from the double-sided adhesive tape 9. The piezoelectric positive electrode 4 and piezoelectric negative electrode 2, serving as charge collection components, are respectively attached to both sides of the piezoelectric material 3, forming a symmetrical electrode structure. The piezoelectric material 3, used for generating dynamic force signals, is attached between the piezoelectric positive electrode 4 and the piezoelectric negative electrode 2, ensuring that external dynamic force is transmitted to the piezoelectric material 3 quickly and without delay. The terminal support tape 1 is attached to the outer edge of the piezoelectric negative electrode 2 away from the piezoelectric material 3, used for mounting the piezoelectric terminal 11, preventing the terminal from shifting under force or vibration.

[0035] The outer encapsulation layer 10 serves as the overall protective component of the sensor. One side covers and encapsulates the outer surface of the PET sheet 7 facing away from the resistive electrode 6, and the other side covers and encapsulates the outer surface of the piezoelectric negative electrode 2 facing away from the piezoelectric material 3. The outer encapsulation layer 10 provides waterproof and dustproof protection, preventing external liquids and dust from entering the sensor and corroding the components. The outer encapsulation layer 10 also enhances the overall integrity of the stacked structure through mechanical reinforcement.

[0036] The implementation principle of this application embodiment is as follows: when the sensor is subjected to a combined force including dynamic force (such as impact, vibration) and static force (such as constant pressure), each unit and component works together to achieve signal acquisition and transmission. The insulating properties of the double-sided adhesive tape 9 ensure that the dynamic charge signal and the static resistance signal do not interfere with each other, the outer encapsulation layer 10 ensures structural stability, and the integrated stacked design reduces the encapsulation process and volume, ultimately achieving complementary integration of dynamic and static measurements.

[0037] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A composite sensor, characterized in that: The device includes a piezoelectric sensing unit (100), a resistance sensing unit (200), double-sided tape (9), and an outer encapsulation layer (10). The piezoelectric sensing unit (100) includes a piezoelectric positive electrode (4), and the resistance sensing unit (200) includes a resistive material (5). The double-sided tape (9) is sandwiched between the piezoelectric positive electrode (4) and the resistive material (5) and bonds them together. The outer encapsulation layer (10) encapsulates the piezoelectric sensing unit (100) and the resistance sensing unit (200) into an integrated structure.

2. The composite sensor according to claim 1, characterized in that: The resistance sensing unit (200) further includes a resistance electrode (6), which is stacked on the side of the resistive material (5) away from the double-sided tape (9) and is laminated and bonded to the resistive material (5).

3. A composite sensor according to claim 2, characterized in that: The resistance sensing unit (200) further includes a PET sheet (7), which covers and encapsulates the side of the resistance electrode (6) away from the resistance material (5) and is laminated and bonded to the resistance electrode (6).

4. A composite sensor according to claim 3, characterized in that: The resistance sensing unit (200) further includes at least one piezoresistive terminal (8), which is attached to the surface of the PET sheet (7) and electrically connected to the resistive electrode (6).

5. A composite sensor according to claim 1, characterized in that: The piezoelectric sensing unit (100) further includes a piezoelectric material (3) and a piezoelectric negative electrode (2), wherein the piezoelectric material (3) and the piezoelectric negative electrode (2) are stacked sequentially on the side of the piezoelectric positive electrode (4) away from the double-sided tape (9).

6. A composite sensor according to claim 5, characterized in that: The piezoelectric sensing unit (100) further includes at least one piezoelectric terminal (11), which is bonded to the piezoelectric negative electrode (2) by a terminal support tape (1) and electrically connected to the piezoelectric negative electrode (2).

7. A composite sensor according to claim 1, characterized in that: The resistance sensing unit (200) further includes a PET sheet (7) and a resistance electrode (6), and the piezoelectric sensing unit (100) further includes a piezoelectric material (3) and a piezoelectric negative electrode (2); the outer encapsulation layer (10) covers the outer side of the PET sheet (7) away from the resistance electrode (6) and the outer side of the piezoelectric negative electrode (2) away from the piezoelectric material (3), respectively.

8. A composite sensor according to claim 2, characterized in that: The double-sided tape (9) is an insulating material used to keep the resistive electrode (6) and the piezoelectric positive electrode (4) insulated.

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