Piezoelectric sensor and piezoelectric device

Abstract

The invention discloses a piezoelectric sensor and piezoelectric equipment, the piezoelectric sensor comprises a sensor body, the sensor body comprises at least one positive electrode layer, at least one middle layer and at least one negative electrode layer which are superposed, and two sides of each middle layer are respectively superposed with one positive electrode layer and one negative electrode layer; the hollow area is arranged on the sensor body and penetrates through the sensor body, a plurality of sensing strips are arranged in the hollow area, each sensing strip comprises at least one positive electrode strip, at least one piezoelectric strip and at least one negative electrode strip which are stacked, and one positive electrode strip and one negative electrode strip are stacked on the two sides of each piezoelectric strip respectively; at least one end of the sensing strip in the length direction is connected with the sensor body, so that the at least one positive electrode strip is connected with the at least one positive electrode layer in a one-to-one manner, and the at least one negative electrode strip is connected with the at least one negative electrode layer in a one-to-one manner. The intensity and the sensitivity of the electric signal can be improved, and the application requirement can be completely met.

Description

Technical Field

[0001] The present application relates to the technical field of piezoelectric sensors, and in particular to a piezoelectric sensor and a piezoelectric device. Background Art

[0002] For piezoelectric devices such as piezoelectric keyboards that use piezoelectric sensors, they are deeply favored by the market because they not only have the function of positioning touch, but also have the function of pressure sensing. Piezoelectric sensors have extremely high application value in new generation human-computer interaction, pressure sensors, electronic skin, medical (heart rate, blood pressure measurement) and other application fields.

[0003] In the related technology, conventional piezoelectric sensors are mainly composed of a piezoelectric layer, positive and negative electrode layers. As for the working principle of the piezoelectric sensor, specifically, when the piezoelectric sensor is subjected to force, the piezoelectric layer is deformed and an electrical signal is generated due to the piezoelectric effect. The magnitude of the force can be judged based on the electrical signal.

[0004] However, the conventional piezoelectric sensors mentioned above have great limitations because in normal application scenarios, conventional piezoelectric sensors do not have a large deformation space, resulting in a small deformation of the piezoelectric sensor, which in turn leads to a weak electrical signal and cannot fully meet application requirements. Summary of the invention

[0005] In view of the above-mentioned deficiencies in the related art, the present application provides a piezoelectric sensor and a piezoelectric device to solve the problem in the related art that the electrical signal is weak due to the small deformation of the piezoelectric sensor.

[0006] In order to solve the above technical problems, in a first aspect, the present application provides a piezoelectric sensor, the piezoelectric sensor comprising:

[0007] A sensor body, the sensor body comprising at least one positive electrode layer, at least one intermediate layer and at least one negative electrode layer stacked along a first direction, wherein one positive electrode layer and one negative electrode layer are stacked on both sides of each intermediate layer in the first direction respectively;

[0008] A hollow area, wherein the hollow area is arranged in the sensor body and penetrates the sensor body along the first direction, a plurality of sensor strips are arranged in the hollow area, each of the sensor strips comprises at least one positive electrode strip, at least one piezoelectric strip and at least one negative electrode strip stacked along its own thickness direction, and a positive electrode strip and a negative electrode strip are stacked on both sides of each piezoelectric strip in the thickness direction, respectively; the length directions of the positive electrode strip, the piezoelectric strip and the negative electrode strip extend in the same direction, and at least one end of the sensor strip in the length direction is connected to the sensor body, so that at least one positive electrode strip is connected one-to-one with at least one positive electrode layer, and at least one negative electrode strip is connected one-to-one with at least one negative electrode layer.

[0009] In a possible implementation manner of the first aspect, one end of the sensor strip in the length direction is connected to the sensor body, and the other end is disconnected from the sensor body.

[0010] In a possible implementation manner of the first aspect, the end of the sensor strip connected to the sensor body is a connection end, and a plurality of the connection ends are arranged in sequence along a second direction, and the second direction is parallel to the intermediate layer;

[0011] The sensor body includes a first inner side surface and a second inner side surface for enclosing the hollow area, and the first inner side surface and the second inner side surface are spaced apart and arranged relatively to each other in a direction different from the second direction; in the second direction, one of any two adjacent connection ends is connected to the first inner side surface, and the other is connected to the second inner side surface.

[0012] In a possible implementation manner of the first aspect, at least one end of the sensor bar in the length direction is a connection end connected to the sensor body, and the connection ends of the plurality of sensor bars are arranged in sequence along a second direction, and the second direction is parallel to the intermediate layer;

[0013] The sensing strips are of equal width, the width direction of the connecting ends extends along the second direction, and the width range of the connecting ends is 50um-500um; and / or, in the second direction, the spacing between two adjacent connecting ends of any two different sensing strips is less than or equal to 20um.

[0014] In a possible implementation manner of the first aspect, an insulating layer is disposed on an outer surface of the sensor bar.

[0015] In a possible implementation manner of the first aspect, at least some of the plurality of sensor bars are cross-stacked.

[0016] In a possible implementation manner of the first aspect, the sensor strip is spiral-shaped.

[0017] In a possible implementation manner of the first aspect, the plurality of sensor bars are arranged in parallel and spaced apart from each other in sequence along the second direction.

[0018] In a possible implementation manner of the first aspect, the piezoelectric sensor includes a flexible packaging layer, which is wrapped around the outer side of the sensor body to encapsulate the plurality of sensor bars in a space surrounded by the flexible packaging layer.

[0019] In a second aspect, the present application further provides a piezoelectric device, the piezoelectric device comprising:

[0020] The piezoelectric sensor according to any one of the first aspects.

[0021] Compared with the related art, this application has at least the following beneficial effects:

[0022] In the present application, when the piezoelectric sensor is used as a sensor, since a plurality of sensing strips are arranged in the hollow area that runs through the sensor body, and since each sensing strip includes a positive electrode strip, a piezoelectric strip, and a negative electrode strip stacked along its own thickness direction, when the sensing strip is subjected to an external force, the piezoelectric strip in the sensing strip will deform, and since the piezoelectric strip has a piezoelectric effect, under the influence of this deformation, the positive and negative charge centers in the piezoelectric strip will be relatively displaced, resulting in polarized charges on its surface, and the positive electrode strip and the negative electrode strip will correspondingly collect the positive and negative charges generated by the piezoelectric strip, thus generating a potential difference between the positive electrode strip and the negative electrode strip, thereby forming an electrical signal. At the same time, since the positive electrode strip is connected to the positive electrode layer and the negative electrode strip is connected to the negative electrode layer, the electrical signal generated by the sensing strip can be transmitted through the positive electrode layer and the negative electrode layer.

[0023] Compared with the complete piezoelectric sensors in the related art that do not have hollow areas and sensor strips, in the present application, since each sensor strip is independent of each other to a certain extent and there is no mutual restraint and constraint, when the sensor strip is subjected to external force, the mutual influence between adjacent sensor strips is small, so that each sensor strip can bend and stretch more freely, thereby being able to undergo greater deformation. In this way, even if the piezoelectric sensor does not have a large deformation space, the sensor strip can undergo a large deformation, thereby being able to improve the strength and sensitivity of the electrical signal, which is conducive to fully meeting application requirements.

[0024] In addition, when the piezoelectric sensor is used as a vibration feedback device, since each sensor bar is independent of each other to a certain extent, the independent sensor bars will vibrate independently of each other. In this way, through the independent vibration of each independent sensor bar, the vibration can have a richer, more diversified and multi-layered effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 A schematic diagram of a piezoelectric sensor provided in an embodiment of the present application;

[0027] Figure 2 One of the schematic diagrams of the sensor body provided in the embodiment of the present application;

[0028] Figure 3 The second schematic diagram of the sensor body provided in the embodiment of the present application;

[0029] Figure 4 The third schematic diagram of the sensor body provided in the embodiment of the present application;

[0030] Figure 5 A fourth schematic diagram of a sensor body provided in an embodiment of the present application;

[0031] Figure 6 A schematic diagram of a piezoelectric device provided in an embodiment of the present application.

[0032] Description of reference numerals:

[0033] 1-sensor body; 11-positive electrode layer; 12-intermediate layer; 13-negative electrode layer; 14-first inner side; 15-second inner side;

[0034] 2-Hollowout area;

[0035] 3-sensing strip; 31-connecting end;

[0036] 4-Flexible packaging layer;

[0037] 10- Piezoelectric sensor;

[0038] 20-substrate; 201-avoidance groove. DETAILED DESCRIPTION

[0039] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0040] In the present application, the terms "upper", "lower", "left", "right", "front", "back", "top", "bottom", "inner", "outer", "vertical", "horizontal", "lateral", "longitudinal" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings. These terms are mainly used to better describe the present application and its embodiments, and are not used to limit the indicated devices, elements or components to have a specific orientation, or to be constructed and operated in a specific orientation.

[0041] In addition, some of the above terms may be used to express other meanings in addition to indicating orientation or positional relationship. For example, the term "on" may also be used to express a certain dependency or connection relationship in some cases. For those of ordinary skill in the art, the specific meanings of these terms in this application can be understood according to specific circumstances.

[0042] In addition, the terms "installed", "set", "provided with", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral structure; it can be a mechanical connection, or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be an internal connection between two devices, elements, or components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0043] In addition, the terms "first", "second", etc. are mainly used to distinguish different devices, elements or components (the specific types and structures may be the same or different), and are not used to indicate or imply the relative importance and quantity of the indicated devices, elements or components. Unless otherwise specified, "plurality" means two or more.

[0044] As described in the background technology of this application, piezoelectric devices such as piezoelectric keyboards that use piezoelectric sensors are deeply favored by the market because they not only have the function of positioning touch but also have the function of pressure sensing. Piezoelectric sensors have extremely high application value in new generation human-computer interaction, pressure sensors, electronic skin, medical (heart rate, blood pressure measurement) and other application fields.

[0045] In the related technology, conventional piezoelectric sensors are mainly composed of a piezoelectric layer, positive and negative electrode layers. As for the working principle of the piezoelectric sensor, specifically, when the piezoelectric sensor is subjected to force, the piezoelectric layer is deformed and an electrical signal is generated due to the piezoelectric effect. The magnitude of the force can be judged based on the electrical signal.

[0046] However, the conventional piezoelectric sensors mentioned above have great limitations because in normal application scenarios, conventional piezoelectric sensors do not have a large deformation space, resulting in a small deformation of the piezoelectric sensor, which in turn leads to a weak electrical signal and cannot fully meet application requirements.

[0047] Embodiment 1

[0048] In view of the above-mentioned problems, the present application provides a piezoelectric sensor to solve the problem in the related art that the electrical signal is weak due to the small deformation of the piezoelectric sensor.

[0049] The technical solution of the present application will be further described below in conjunction with specific embodiments and drawings:

[0050] like Figure 1 , Figure 2 and Figure 3 As shown, the piezoelectric sensor 10 includes a sensor body 1 and a hollow area 2. Figure 1 As shown, the sensor body 1 includes a first direction (such as Figure 1 At least one positive electrode layer 11, at least one intermediate layer 12 and at least one negative electrode layer 13 are stacked (in the Z direction in the first direction), and a positive electrode layer 11 and a negative electrode layer 13 are stacked on both sides of each intermediate layer 12 in the first direction.

[0051] The hollow area 2 is arranged in the sensor body 1 and penetrates the sensor body 1 along the first direction. A plurality of sensor strips 3 are arranged in the hollow area 2. Each sensor strip 3 includes at least one positive electrode strip, at least one piezoelectric strip and at least one negative electrode strip (not shown in the figure) stacked along its own thickness direction. A positive electrode strip and a negative electrode strip are stacked on both sides of each piezoelectric strip in the thickness direction, respectively.

[0052] The length directions of the positive electrode strips, the piezoelectric strips and the negative electrode strips extend in the same direction, and at least one end of the sensing strip 3 in the above-mentioned length direction is connected to the sensor body 1, so that at least one positive electrode strip is connected one-to-one with at least one positive electrode layer 11, and at least one negative electrode strip is connected one-to-one with at least one negative electrode layer 13.

[0053] In the present application, when the piezoelectric sensor 10 is used as a sensor, since a plurality of sensor strips 3 are arranged in the hollow area 2 that runs through the sensor body 1, and since each sensor strip 3 includes a positive electrode strip, a piezoelectric strip, and a negative electrode strip stacked along its own thickness direction, when the sensor strip 3 is subjected to an external force, the piezoelectric strip in the sensor strip 3 will deform, and since the piezoelectric strip has a piezoelectric effect, under the influence of this deformation, the positive and negative charge centers in the piezoelectric strip will be relatively displaced, resulting in polarized charges on its surface, and the positive electrode strip and the negative electrode strip will collect the positive and negative charges generated by the piezoelectric strip accordingly, so that a potential difference will be generated between the positive electrode strip and the negative electrode strip, thereby forming an electrical signal. At the same time, since the positive electrode strip is connected to the positive electrode layer 11 and the negative electrode strip is connected to the negative electrode layer 13, the electrical signal generated by the sensor strip 3 can be transmitted through the positive electrode layer 11 and the negative electrode layer 13.

[0054] Compared with the complete piezoelectric sensor without hollow areas and sensor bars 3 in the related art, in the present application, since each sensor bar 3 is independent of each other to a certain extent and there is no mutual restraint and constraint, when the sensor bar 3 is subjected to external force, the mutual influence between adjacent sensor bars 3 is small, so that each sensor bar 3 can bend and stretch more freely, thereby being able to undergo greater deformation. In this way, even if the piezoelectric sensor 10 does not have a large deformation space, the sensor bar 3 can undergo a large deformation, thereby being able to improve the strength and sensitivity of the electrical signal, which is conducive to fully meeting application requirements.

[0055] In addition, when the piezoelectric sensor 10 is used as a vibration feedback device, since each sensor bar 3 is independent of each other to a certain extent, the independent sensor bars 3 will vibrate independently of each other. In this way, through the independent vibration of each independent sensor bar, the vibration can have a richer, more diversified and multi-layered effect.

[0056] For the piezoelectric sensor 10, in this embodiment, the piezoelectric sensor 10 is a single-layer piezoelectric structure, that is, the sensor body 1 includes a positive electrode layer 11, an intermediate layer 12 and a negative electrode layer 13, and correspondingly, each sensor strip 3 includes a positive electrode strip, a piezoelectric strip and a negative electrode strip.

[0057] In other embodiments, the piezoelectric sensor 10 can also be a multilayer piezoelectric structure, that is, the sensor body 1 includes multiple positive electrode layers 11, multiple intermediate layers 12 and multiple negative electrode layers 13, and correspondingly, each sensor strip 3 includes multiple positive electrode strips, multiple piezoelectric strips and multiple negative electrode strips.

[0058] Specifically, when the piezoelectric sensor 10 is used as a sensor, the positive electrode layer 11, the middle layer 12, the negative electrode layer 13, the middle layer 12, and the positive electrode layer 11 are stacked in sequence along the first direction. When the piezoelectric sensor 10 is used as a vibration feedback device, a positive electrode layer 11, an middle layer 12, and a negative electrode layer 13 constitute a piezoelectric unit, and a plurality of piezoelectric units are stacked in sequence along the first direction, and an isolation layer is stacked between any two adjacent piezoelectric units.

[0059] Regarding the sensor strips 3 , in one implementation, on a complete sensor body 1 , the entire sensor body 1 is cut once at a certain interval, thereby not only cutting out the hollow area 2 on the sensor body 1 , but also cutting out a plurality of sensor strips 3 located in the hollow area 2 .

[0060] The sensing strip 3 is formed by cutting, so that the sensing strip 3 and the sensor body 1 can be connected integrally, which is beneficial to ensure the reliability of the connection between the sensing strip 3 and the sensor body 1, and further beneficial to ensure that the piezoelectric sensor 10 can have a longer service life.

[0061] In another embodiment, the sensor strip 3 can be manufactured separately, and after the sensor strip 3 is manufactured, the sensor strip 3 can be connected to the hollow area 2 on the sensor body 1. Such a configuration is conducive to facilitating the formation of the sensor strip 3 to a certain extent.

[0062] In the first embodiment, the middle layer 12 is a complete piezoelectric sheet, and each piezoelectric strip of each sensor strip 3 is connected to the piezoelectric sheet. This configuration simplifies the structure of the middle layer 12 to a certain extent, which is conducive to the processing and manufacturing of the middle layer 12.

[0063] In the second embodiment, the middle layer 12 may also include a plurality of piezoelectric strips, and the plurality of piezoelectric strips in the middle layer 12 are connected to the piezoelectric strips in the plurality of sensing strips 3. In this configuration, since there is a gap between any two adjacent piezoelectric strips in the middle layer 12, the gap not only helps to reduce the weight of the middle layer 12, and thus helps to reduce the weight of the entire piezoelectric sensor 10, but also helps to reduce the amount of piezoelectric material used, which helps to reduce costs.

[0064] In the third embodiment, the middle layer 12 is not a piezoelectric layer but a filling material layer, in which case the piezoelectric strips in the sensor strips 3 may not be connected to the middle layer 12. This arrangement is conducive to further reducing the amount of piezoelectric material used, thereby further reducing costs.

[0065] Regarding the filling material layer, in the embodiment of the present application, the constituent material of the filling material layer may be an insulating material, a damping material, etc. The selection of the constituent material of the filling material layer is relatively flexible, and the embodiment of the present application does not make any specific limitation on this.

[0066] Regarding the positive electrode layer 11 and the negative electrode layer 13 , in one embodiment, the positive electrode layer 11 and the negative electrode layer 13 each include a complete electrode sheet layer, and each electrode strip of each sensing strip is connected to the corresponding electrode sheet layer.

[0067] With such a configuration, on the one hand, since the positive electrode layer 11 and the negative electrode layer 13 cannot distinguish the signal of each piezoelectric strip in this case, it is suitable for application scenarios where only the pressing pressure needs to be confirmed without confirming the pressing position; on the other hand, to a certain extent, the structure of the positive electrode layer 11 and the negative electrode layer 13 is simplified, which is conducive to facilitating the processing and manufacturing of the positive electrode layer 11 and the negative electrode layer 13.

[0068] In another embodiment, the positive electrode layer 11 and the negative electrode layer 13 respectively include multiple electrode strips, and the multiple electrode strips in the positive electrode layer 11 are connected one-to-one with the positive electrode strips in the multiple sensing strips, and the multiple electrode strips in the negative electrode layer 13 are connected one-to-one with the negative electrode strips in the multiple sensing strips.

[0069] With such arrangement, on the one hand, since the electrode strips in the positive electrode layer 11 and the negative electrode layer 13 are independent, the signal transmission of each electrode strip is also independent, so that the signal of the piezoelectric strip in each sensor strip can be distinguished separately, which is not only suitable for application scenarios of confirming the pressing pressure, but also only suitable for application scenarios of confirming the pressing position; on the other hand, since there is a gap between any two adjacent electrode strips, the gap is not only helpful to reduce the weight of the positive electrode layer 11 and the negative electrode layer 13, and thus helps to reduce the weight of the entire piezoelectric sensor 10, but also helps to reduce the material usage of the positive electrode layer 11 and the negative electrode layer 13, which helps to reduce costs.

[0070] As for the hollow area 2, in the embodiment of the present application, the hollow area 2 can be formed by a perforation set on the sensor body 1, or can be formed by a notch set on the sensor body 1, that is, in a direction perpendicular to the first direction, the hollow area 2 runs through the side of the sensor body 1. The structural setting of the hollow area 2 is relatively flexible, and the embodiment of the present application does not make specific limitations on this.

[0071] Regarding the shape of the hollow area 2, in the embodiment of the present application, the shape of the hollow area 2 can be rectangular, circular or any other shape. For example, when the shape of the hollow area 2 is circular, the inner side surface surrounding the hollow area 2 is a cylindrical surface, and in this case, the first inner side surface 14 and the second inner side surface 15 both belong to the cylindrical surface. The shape of the hollow area 2 is flexible, and the embodiment of the present application does not specifically limit this.

[0072] Regarding the shape of the piezoelectric sensor 10, in the embodiment of the present application, the shape of the piezoelectric sensor 10 can be rectangular, circular or any other shape. The shape setting of the piezoelectric sensor 10 is relatively flexible, and the embodiment of the present application does not make any specific limitation on this.

[0073] Regarding the connection between the sensor strip 3 and the sensor body 1, in a first embodiment, as Figure 2 As shown, the length direction of the sensor strip 3 (such as Figure 2 One end in the X direction (in the X direction) is connected to the sensor body 1, and the other end is disconnected from the sensor body 1.

[0074] With such a configuration, the disconnected end can move freely to a certain extent, and the end can also increase the degree of freedom of the sensor bar 3. When subjected to force, the sensor bar 3 will be subject to fewer constraints and obstacles from the surroundings, and can stretch and contract more freely, so that it can have a larger deformation, which is conducive to further improving the strength and sensitivity of the electrical signal, and at the same time, it is also conducive to further making the vibration of the sensor bar 3 have a richer, more diversified and multi-level effect.

[0075] Furthermore, in a preferred embodiment, one end of the sensor strip 3 connected to the sensor body 1 is a connecting end 31, and a plurality of connecting ends 31 are connected along the second direction (eg Figure 2 The second direction is parallel to the intermediate layer 12.

[0076] like Figure 2 As shown, the sensor body 1 includes a first inner side surface 14 and a second inner side surface 15 for enclosing the hollow area 2. The first inner side surface 14 and the second inner side surface 15 are spaced apart and arranged opposite to each other in a direction different from the second direction. In the second direction, one of any two adjacent connection ends 31 is connected to the first inner side surface 14, and the other is connected to the second inner side surface 15.

[0077] Since the two adjacent connection ends 31 are respectively connected to the two opposite inner side surfaces, the other end of the sensor strip 3 can move freely, which is also conducive to evenly distributing the sensor strip 3 in the hollow area 2. In this way, when subjected to external force, the force can also be evenly dispersed to different parts of the sensor body 1 through the sensor strip 3, which is conducive to reducing the concentration of local stress, and further conducive to improving the durability and stability of the piezoelectric sensor 10. Secondly, the uniform distribution of the sensor strip 3 enables the sensor strip 3 to more comprehensively and evenly reflect the force situation when sensing external force, which is conducive to reducing measurement errors. Furthermore, in the direction of the arrangement of the first inner side surface 14 and the second inner side surface 15, the alternating connection method of the connection end 31 makes the structure of the piezoelectric sensor 10 more symmetrical, reducing the performance deviation caused by structural asymmetry.

[0078] In another embodiment, without considering the above effects such as uniform distribution of the sensor strips 3, each connection end 31 may also be connected to the first inner side surface 14 or the second inner side surface 15. Such a configuration simplifies the connection between the sensor strips 3 and the sensor body 1 to a certain extent, which is conducive to facilitating the manufacture of the sensor body 1.

[0079] In another embodiment, two sensor bars 3 form a sensor bar group, and the multiple sensor bar groups are arranged in sequence along the second direction, and in the same sensor bar group, the connection end 31 of one sensor bar 3 is connected to the first inner side surface 14, and the connection end 31 of another sensor bar 3 is connected to the second inner side surface 15, and the two connection ends 31 are arranged opposite to each other. Such an arrangement is not only conducive to uniformly sensing and transmitting external forces from different directions, but also can effectively utilize limited space.

[0080] Furthermore, an insulating layer (not shown in the figure) is disposed on the outer surface of the sensor strip 3 .

[0081] Since one end of the sensor bar 3 can move freely, the sensor bar 3 where the end is located is likely to contact other sensor bars 3 during the movement of the end. Therefore, by providing an insulating layer on the outer surface of the sensor bar 3, a short circuit can be avoided when the sensor bars 3 contact each other, which is conducive to ensuring the normal use of the piezoelectric sensor 10.

[0082] Regarding the material of the insulating layer, in the embodiment of the present application, the material of the insulating layer can be acrylate, polyurethane, perfluororesin, etc. The material selection of the insulating layer is relatively flexible, and the embodiment of the present application does not make any specific limitation on this.

[0083] Further, regarding the arrangement of the sensor strip 3 in the hollow area 2, in the first embodiment, as Figure 4 As shown, at least some of the plurality of sensor bars 3 are cross-stacked.

[0084] The cross-stacked structure increases the gaps and spaces between the sensor bars 3, so that when subjected to external forces, these gaps and spaces provide more space for the sensor bars 3 to bend, twist and stretch, allowing them to undergo more complex and larger deformations, which is beneficial to further improve the strength and sensitivity of the electrical signal.

[0085] In this embodiment, since the disconnected end of the sensor bar 3 can move freely to a certain extent, the sensor bars 3 are arranged in a cross-stacked manner as the end moves freely. In this way, the cross-stacked arrangement of the sensor bars 3 is facilitated to a certain extent.

[0086] In the second embodiment, if Figure 5 As shown, the sensor strip 3 is spiral-shaped.

[0087] First, the spiral structure itself has greater elasticity and scalability. Compared with a linear structure, the spiral sensor strip 3 can be stretched, compressed and twisted along the spiral path when subjected to external force, thereby achieving more dimensional and larger deformations, which is beneficial to further improve the strength and sensitivity of the electrical signal.

[0088] Secondly, the layout of the spiral sensor strip 3 in space is more complex, and the contact and interaction with the surrounding environment are more diverse. When an external force acts, the spiral sensor strip 3 can not only be stretched in the axial direction, but also bend and twist in the radial direction, so that the entire space can be used to achieve deformation, increasing the possibility and amplitude of deformation.

[0089] Furthermore, the spiral design enables the sensor strip 3 to disperse stress when subjected to force. The force is not concentrated at a specific point or area, but is evenly distributed along the spiral line, which helps to avoid local excessive deformation or damage, thereby allowing the sensor strip 3 to produce a larger overall deformation as a whole.

[0090] In this embodiment, the sensor strip 3 is pulled at one end that is disconnected, and the sensor strip 3 is stretched along the length direction of the sensor strip 3, so that after the sensor strip 3 is loosened, the naturally relaxed sensor strip 3 will be in a spiral shape, which also facilitates the formation of the spiral sensor strip 3.

[0091] In the third embodiment, if Figure 2 As shown, a plurality of sensor strips 3 are arranged in parallel and spaced order along the second direction.

[0092] Such an arrangement, firstly, facilitates orderly signal transmission and processing. The parallel and spaced arrangement makes it possible for the electrical signals generated by each sensor strip 3 to interfere less with each other during the transmission process, and the subsequent signal processing circuit can more clearly distinguish and process the signals from each sensor strip 3, thereby improving the accuracy and reliability of the measurement.

[0093] Secondly, it is conducive to uniformly sensing the external force distribution. This arrangement can make the piezoelectric sensor 10 receive the external force more uniformly in the second direction, avoiding the situation where the force is concentrated locally but not effectively sensed by other parts, thereby reflecting the force condition more comprehensively and accurately.

[0094] Furthermore, it is convenient for manufacturing and installation. The parallel and spaced arrangement makes it easier to achieve standardized processes during the manufacturing process, thereby improving production efficiency and consistency of product quality.

[0095] In this embodiment, since there is a gap between any two adjacent sensor bars 3 , the sensor bars 3 may be provided with an insulating layer or may not be provided with an insulating layer, which is not specifically limited in the embodiment of the present application.

[0096] In addition, in order to ensure that the sensor bars 3 can be arranged in parallel and spaced apart along the second direction, a material with good elasticity may be filled between two adjacent sensor bars 3 . The specific material of the material is not specifically limited in the embodiment of the present application.

[0097] Regarding the connection between the sensor strip 3 and the sensor body 1, in the second embodiment, as shown in FIG. Figure 3 As shown, both ends of each sensor bar 3 in the length direction are connection ends 31 , and in the same sensor bar 3 , one of the two connection ends 31 is connected to the first inner side surface 14 , and the other is connected to the second inner side surface 15 .

[0098] This arrangement firstly enhances the stability and reliability of the sensor strip 3. The connection at both ends makes it difficult for the sensor strip 3 to shift or twist excessively when subjected to external forces, thereby reducing the risk of measurement errors or damage caused by instability.

[0099] Secondly, the force transmission efficiency is improved. The external force can be more effectively transmitted to the sensor bar 3 through the connections at both ends, so that it can more sensitively sense and respond to changes in the external force, thereby improving the measurement accuracy and sensitivity of the piezoelectric sensor 10.

[0100] When external force acts on the piezoelectric sensor 10, the two ends are connected to the opposite inner side surfaces respectively, so that the sensor strip 3 can bear the force more evenly in the length direction, avoiding the situation where one end is subjected to excessive force while the other end is subjected to too little force, and further improving the accuracy and stability of the measurement.

[0101] In this embodiment, the piezoelectric sensor 10 can be any piezoelectric sensor 10 in the first embodiment described above, and can bring the same or similar beneficial effects. For example, in this embodiment, an insulating layer can be provided on the outer surface of the sensor bar 3, at least some of the multiple sensor bars 3 can be cross-stacked, the sensor bars 3 can be spiral-shaped, and the multiple sensor bars 3 can be arranged in parallel and spaced order along the second direction, etc. This embodiment of the present application will not be elaborated in detail.

[0102] For the size of the sensor strip 3, further, as Figure 2 and Figure 3 As shown, at least one end of the sensor strip 3 in the length direction is a connection end 31 connected to the sensor body 1, and the connection ends 31 of the plurality of sensor strips 3 are connected along the second direction (eg Figure 2 The second direction is parallel to the intermediate layer 12.

[0103] like Figure 2 and Figure 3As shown, the sensor strips 3 are of equal width, the width direction of the connection end 31 extends along the second direction, and the width range of the connection end 31 is 50um-500um; and / or, in the second direction, the spacing between two adjacent connection ends 31 of any two different sensor strips 3 is less than or equal to 20um.

[0104] Since the width of the connection end 31 ranges from 50um to 500um, and since the sensor strips 3 are sensor strips 3 of equal width, the width of the sensor strips 3 ranges from 50um to 500um. With such a configuration, firstly, in terms of sensitivity, a narrower width (such as close to 50um) can make the sensor strip 3 more easily deformed, thereby being more sensitive to smaller external force changes, which is beneficial to improving the sensitivity of detection. A wider width (such as close to 500um) can ensure that the sensor strip 3 has a certain strength and stability, and is suitable for detecting larger external forces.

[0105] Secondly, from the perspective of manufacturing technology, this width range is feasible and easy to achieve with current processing technology, and can ensure high production yield and consistency.

[0106] Furthermore, in terms of space utilization, a reasonable setting of the width range can arrange more sensor strips 3 in a limited space, thereby improving detection density and resolution.

[0107] When multiple sensor bars 3 are arranged in parallel and spaced in sequence along the second direction, the spacing between any two adjacent sensor bars 3 is less than or equal to 20um. Therefore, in such a configuration, firstly, a smaller spacing can allow more piezoelectric materials to participate in sensing, thereby enabling the piezoelectric sensor 10 to more sensitively sense small external force changes and subtle physical quantity differences, thereby improving the resolution and accuracy of detection. Secondly, from the perspective of manufacturing process and cost, a spacing range of less than or equal to 20um is relatively easy to achieve under the current manufacturing technology level, which can not only ensure the feasibility and stability of production, but also control production costs.

[0108] In a preferred embodiment, the width of the connection end 31 ranges from 50um to 500um, and the distance between any two adjacent connection ends 31 of two different sensor strips 3 is less than or equal to 20um. This configuration further optimizes the size of the sensor strip 3, thereby further improving the resolution and accuracy of the detection.

[0109] In the embodiment of the present application, the width of the sensor strip 3 may be 50 um, 500 um, or any value within the range of 50 um-500 um, which is not specifically limited in the embodiment of the present application.

[0110] Regarding the spacing between the connection terminals 31 , in the embodiment of the present application, the spacing between the connection terminals 31 may be 20 um, or may be any value less than 20 um, and the embodiment of the present application does not specifically limit this.

[0111] like Figure 1 As shown, the piezoelectric sensor 10 includes a flexible packaging layer 4 , which is wrapped around the outside of the sensor body 1 to encapsulate a plurality of sensor strips 3 in a space surrounded by the flexible packaging layer 4 .

[0112] In this way, on the one hand, the flexible packaging layer 4 can play a good protective role, which is conducive to preventing corrosion and damage to the sensor body 1 and the sensor bar 3, thereby helping to improve the stability and reliability of the piezoelectric sensor 10 and extend its service life. On the other hand, the flexible packaging layer 4 can not only provide sufficient deformation space for the deformation of the sensor bar 3, but also limit the excessive displacement and deformation of the sensor bar 3, so that it maintains good performance.

[0113] Regarding the material of the flexible encapsulation layer 4 , in the embodiment of the present application, the material of the flexible encapsulation layer 4 may be PET, PDMS, PMMA, etc., and the embodiment of the present application does not make any specific limitation on this.

[0114] Embodiment 2

[0115] The present application also provides a piezoelectric device, such as Figure 6 As shown, the piezoelectric device includes a piezoelectric sensor 10 and a substrate 20, wherein the substrate 20 and the piezoelectric sensor 10 are aligned along a first direction (eg Figure 6 The piezoelectric sensor 10 is stacked in the Z direction, and the structure is the same as that of any piezoelectric sensor 10 in the above-mentioned embodiments, and can bring the same or similar beneficial effects. The details can be referred to the description in the above-mentioned embodiments, and the present embodiment will not be described in detail here.

[0116] Compared with the complete piezoelectric sensor without hollow areas and sensor bars 3 in the related art, in the present application, since each sensor bar 3 is independent of each other to a certain extent and there is no mutual restraint and constraint, when the sensor bar 3 is subjected to external force, the mutual influence between adjacent sensor bars 3 is small, so that each sensor bar 3 can bend and stretch more freely, thereby being able to undergo greater deformation. In this way, even if the force loaded on the sensor bar 3 is very weak, the sensor bar 3 can undergo greater deformation, thereby being able to improve the strength and sensitivity of the electrical signal, which is conducive to fully meeting the application requirements.

[0117] Furthermore, if Figure 6 As shown, the substrate 20 is an elastic substrate; and / or, a side of the substrate 20 facing the piezoelectric sensor is provided with an avoidance groove 201, and the avoidance groove 201 is provided corresponding to the hollow area 2 in the first direction.

[0118] First, the substrate 20 is set as an elastic substrate, so that when subjected to force, the elastic deformation of the substrate 20 can provide a larger deformation space for the deformation of the sensor bar 3, so that the sensor bar 3 can be deformed more, which is conducive to further improving the strength and sensitivity of the electrical signal. Secondly, when subjected to force, the avoidance groove 201 can provide a larger deformation space for the deformation of the sensor bar 3, so that the sensor bar 3 can be deformed more, which is conducive to further improving the strength and sensitivity of the electrical signal.

[0119] like Figure 6 As shown, in a preferred embodiment, the substrate 20 is an elastic substrate, and a side of the substrate 20 facing the piezoelectric sensor is provided with an avoidance groove 201.

[0120] With such arrangement, when subjected to force, the elastic substrate and the avoidance groove 201 can further provide a larger deformation space for the deformation of the sensor bar 3, thereby further causing the sensor bar 3 to deform more, thereby facilitating further improvement of the strength and sensitivity of the electrical signal.

[0121] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A piezoelectric sensor, characterized in that: include: A sensor body, the sensor body comprising at least one positive electrode layer, at least one intermediate layer and at least one negative electrode layer stacked along a first direction, wherein one positive electrode layer and one negative electrode layer are stacked on both sides of each intermediate layer in the first direction respectively; A hollow area, wherein the hollow area is arranged in the sensor body and penetrates the sensor body along the first direction, a plurality of sensor strips are arranged in the hollow area, each of the sensor strips comprises at least one positive electrode strip, at least one piezoelectric strip and at least one negative electrode strip stacked along its own thickness direction, and a positive electrode strip and a negative electrode strip are stacked on both sides of each piezoelectric strip in the thickness direction, respectively; the length directions of the positive electrode strip, the piezoelectric strip and the negative electrode strip extend in the same direction, and at least one end of the sensor strip in the length direction is connected to the sensor body, so that at least one positive electrode strip is connected one-to-one with at least one positive electrode layer, and at least one negative electrode strip is connected one-to-one with at least one negative electrode layer.

2. The piezoelectric sensor according to claim 1, characterized in that One end of the sensor strip in the length direction is connected to the sensor body, and the other end is disconnected from the sensor body.

3. The piezoelectric sensor according to claim 2, characterized in that: The end of the sensor strip connected to the sensor body is a connection end, and a plurality of the connection ends are arranged in sequence along a second direction, and the second direction is parallel to the middle layer; The sensor body includes a first inner side surface and a second inner side surface for enclosing the hollow area, and the first inner side surface and the second inner side surface are spaced apart and arranged relatively to each other in a direction different from the second direction; in the second direction, one of any two adjacent connection ends is connected to the first inner side surface, and the other is connected to the second inner side surface.

4. The piezoelectric sensor according to claim 1, characterized in that: At least one end of the sensor strip in the length direction is a connection end connected to the sensor body, and the connection ends of the plurality of sensor strips are arranged in sequence along a second direction, and the second direction is parallel to the intermediate layer; The sensing strips are of equal width, the width direction of the connecting ends extends along the second direction, and the width range of the connecting ends is 50um-500um; and / or, in the second direction, the spacing between two adjacent connecting ends of any two different sensing strips is less than or equal to 20um.

5. The piezoelectric sensor according to any one of claims 1 to 4, characterized in that: An insulating layer is disposed on the outer surface of the sensor strip.

6. The piezoelectric sensor according to claim 5, characterized in that: At least some of the plurality of sensor bars are cross-stacked.

7. The piezoelectric sensor according to claim 5, characterized in that: The sensor strip is in a spiral shape.

8. The piezoelectric sensor according to any one of claims 1 to 4, characterized in that: The plurality of sensor strips are arranged in parallel and spaced order along the second direction.

9. The piezoelectric sensor according to any one of claims 1 to 4, characterized in that: The piezoelectric sensor comprises a flexible packaging layer, and the flexible packaging layer is wrapped around the outer side of the sensor body so as to package the plurality of sensing strips in a space surrounded by the flexible packaging layer.

10. A piezoelectric device, characterized in that: include: The piezoelectric sensor according to any one of claims 1 to 9.

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