Pressure sensor

Abstract

The invention relates to the technical field of sensors, in particular to a pressure sensor, which is characterized in that a packaging layer and a substrate layer are made of flexible materials, and a sensor main body is made of flexible stretchable, liquid-state or transition-state conductive materials. By utilizing the characteristics of flexibility, elasticity and stretchability of the material, on one hand, the overall mechanical performance of the pressure sensor can be improved, and the service life is prolonged; and on the other hand, the sensor can be used for pressure detection of a complex curved surface, is not easy to damage during non-vertical force measurement, and facilitates the design of a multi-layer sensor main body.

Description

Technical Field

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

[0002] Traditional pressure-sensitive pressure sensors are typically made of plastic film. However, this material results in a shorter lifespan and is easily damaged by forces not perpendicular to the contact surface (such as shear or torsional forces). This makes it difficult to use on complex curved surfaces (such as skin) or with silicone materials commonly used in medical and bionic applications. Furthermore, traditional pressure-sensitive pressure sensors, in principle, must directly contact the pressure surface. If designed as a multi-layer structure, sensors in layers other than the contact layer will not function properly, making a multi-layer structure unsuitable. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the purpose of the present invention is to provide a pressure sensor to solve the problems in the prior art that traditional pressure-sensitive pressure sensors have a short lifespan, are easily damaged when performing non-vertical force measurements, cannot perform pressure detection on complex curved surfaces, and cannot be set up with a multi-layer structure.

[0004] To achieve the above-mentioned objectives and other related objectives, the present invention provides a pressure sensor, which includes a packaging layer, a base layer, and at least one sensor body fixedly arranged between the packaging layer and the base layer. The packaging layer and the base layer are both made of flexible materials. The sensor body is made of flexible, stretchable, liquid or transitional conductive material. When the sensor body is multi-layered, the multi-layer sensor bodies are arranged at intervals up and down, and an isolation layer is arranged between two adjacent layers of the sensor bodies. The isolation layer is made of flexible material.

[0005] Optionally, an adhesive is further provided between the base layer and the packaging layer, and the sensor body is sealed between the base layer and the packaging layer by the adhesive.

[0006] Optionally, the sensor body includes a detection portion, a wire portion, and an interface portion;

[0007] The wire portion includes a first wire segment and multiple second wire segments, and the detection portion and the interface portion are also provided with multiple ones, one end of the multiple detection portions is connected to one end of the interface portion through a common first wire segment, and the other ends of the multiple detection portions are connected to one end of the multiple interface portions through multiple second wire segments, one by one, and all the interface portions are provided on the same side; or

[0008] The wire portion includes multiple second wire segments, and the detection portion and the interface portion are also provided with multiple ones. The two ends of the multiple detection portions are respectively connected to one end of the interface portion through the second wire segments, and all the interface portions are arranged on the same side.

[0009] Optionally, the encapsulation layer and the base layer are made of the same flexible material. When the isolation layer is included, the isolation layer is made of the same flexible material as the encapsulation layer and the base layer.

[0010] The detection part, the wire part and the interface part are made of the same flexible, stretchable, liquid or transitional conductive material.

[0011] Optionally, the line width of the detection portion is ≤ the line width of the wire portion ≤ the line width of the interface portion;

[0012] The detection portion is in the shape of a long line or an S-shaped line as a whole;

[0013] When the wire portion includes the first wire segment, a portion of the first wire segment connected to the detection portion is in an arc shape or a straight line shape as a whole.

[0014] Optionally, when the pressure sensor adopts a multi-layer sensor body, the multiple sensor bodies can be a combination of capacitive sensors and resistive sensors arranged at intervals, or all of the sensor bodies can be capacitive sensors or resistive sensors.

[0015] Optionally, the pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of a left-tilt sensor body and a right-tilt sensor body, the left-tilt sensor body and the right-tilt sensor body are axially symmetrically arranged on the same projection plane, and the detection parts corresponding to the left-tilt sensor body and the right-tilt sensor body are both arranged at an angle to the horizontal direction, and the interface parts of the left-tilt sensor body and the right-tilt sensor body overlap.

[0016] Optionally, the pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of a horizontal sensor body and a vertical sensor body, the detection parts of the horizontal sensor body and the vertical sensor body intersect vertically, and the second wire segment of the horizontal sensor body is flipped together with the corresponding interface part, so that the interface part corresponding to the horizontal sensor body overlaps with the interface part corresponding to the vertical sensor body, and the second wire segment of the horizontal sensor body is flipped as an independent layer.

[0017] Optionally, the pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of two horizontal sensor bodies and one vertical sensor body. The interface parts of the two horizontal sensor bodies are arranged on the same side as the interface part of the vertical sensor body. The detection parts of the two horizontal sensor bodies are both arranged in a trapezoidal shape and the detection parts of the two horizontal sensor bodies can be spliced ​​into a complete horizontal layer.

[0018] Optionally, the pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of a vertical sensor body, a left-tilted sensor body and a right-tilted sensor body. The length direction of the detection part of the vertical sensor body is perpendicular to the horizontal line and is symmetrically arranged on the left and right sides. The interface parts of the left-tilted sensor body and the right-tilted sensor body overlap with the interface parts of the vertical sensor body, and the left-tilted sensor body and the right-tilted sensor body are axially symmetrically arranged.

[0019] In a pressure sensor of the present invention, the encapsulation layer and base layer are constructed of flexible materials, and the sensor body is constructed of a flexible, stretchable, liquid, or transitional conductive material. Leveraging the material's flexibility, elasticity, and stretchability, the sensor's overall mechanical performance is enhanced, extending its service life. Furthermore, the sensor can be used for pressure detection on complex curved surfaces, is less susceptible to damage during non-vertical force measurements, and facilitates the design of a multi-layer sensor body. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 1 is a schematic diagram of the overall structure of a single-layer pressure sensor in one embodiment of the present invention;

[0021] Figure 2 1 is a schematic diagram of the overall structure of a double-layer pressure sensor in one embodiment of the present invention;

[0022] Figure 3 is a schematic structural diagram of a sensor body in one embodiment of the present invention;

[0023] Figure 4 is a structural schematic diagram of a sensor body in another embodiment of the present invention;

[0024] Figure 5 is a structural schematic diagram of a sensor body in yet another embodiment of the present invention;

[0025] Figure 6 Schematic diagram of the main structure of an inclined grid-shaped multi-layer sensor in one embodiment of the present invention;

[0026] Figure 7 is a schematic diagram of the main structure of an inclined grid-shaped multi-layer sensor in another embodiment of the present invention;

[0027] Figure 8 is a schematic diagram of the main structure of an inclined grid-shaped multi-layer sensor in another embodiment of the present invention;

[0028] Figure 9 yes Figure 8 Schematic diagram of the structure of the left tilt sensor body and the right tilt sensor body after being unfolded left and right;

[0029] Figure 10 This is a schematic diagram of the main structure of a multi-layer sensor with independent wire layers in a grid pattern according to an embodiment of the present invention;

[0030] Figure 11 Schematic diagram of the main structure of a multi-layer sensor with overlapping horizontal trapezoidal grids in one embodiment of the present invention;

[0031] Figure 12 yes Figure 11 Schematic diagram of the structure of two horizontal sensor bodies and one vertical sensor body after being unfolded left and right;

[0032] Figure 13 1 is a schematic diagram of the main structure of an axisymmetric multi-layer sensor in one embodiment of the present invention;

[0033] Figure 14 yes Figure 13 Schematic diagram of the vertical sensor body, left tilt sensor body, and right tilt sensor body structures after being unfolded left and right. DETAILED DESCRIPTION

[0034] Refer to the following Figures 1 to 14 A pressure sensor of the present invention is described. In the description of this embodiment, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0035] like Figure 1 and Figure 2As shown in FIG, an embodiment of the present invention provides a pressure sensor, which includes a packaging layer 1, a base layer 2, and at least one sensor body 3 fixedly disposed between the packaging layer 1 and the base layer 2. The pressure sensor can be configured as a single-layer or multi-layer sensor body 3 pressure sensor according to actual needs. In the case of a multi-layer sensor body 3 pressure sensor, the multi-layer sensor body 3 is disposed between the packaging layer 1 and the base layer 2 with an upper and lower spacing. An isolation layer is provided between two adjacent layers of the sensor body 3. Figure 1 As shown in FIG, it is a schematic diagram of the pressure sensor structure when the sensor body 3 is a single layer. The pressure sensor is divided into a packaging layer 1, a sensor body 3 and a base layer 2 from top to bottom. Figure 2 As shown, it is a schematic diagram of the pressure sensor structure when the double-layer sensor body 3 is used. The pressure sensor is divided into a packaging layer 1, a sensor body 3, an isolation layer, a sensor body 3, and a base layer 2 from top to bottom.

[0036] Furthermore, the encapsulation layer 1, base layer 2, and isolation layer are all made of flexible materials. Specifically, the encapsulation layer 1, base layer 2, and isolation layer can be one or more of silicone, organosilicon, PDMS, hydrogel, silicone rubber, PI film, TPU, TPE, nanocomposite elastomer, polylactic acid, natural rubber, and the like. Optionally, the encapsulation layer 1, base layer 2, and isolation layer are all made of the same flexible material, such as silicone. Silicone, due to its properties, has good resilience, thereby extending its service life.

[0037] Furthermore, the sensor body 3 is made of a flexible, stretchable, liquid or transitional conductive material. Specifically, the sensor body 3 can be one of liquid metal materials, carbon nanotube materials, conductive silver paste materials, conductive polymer materials, graphene materials, nanometal materials, and conductive hydrogel materials.

[0038] Optionally, pressure sensors can be placed on action clothing, such as the fingertips of gloves, to detect fingertip pressure. They can also be placed on the fingertips of a robot's hand for tactile sensing. They can also be used to detect tensile forces on planar or non-planar surfaces.

[0039] By making the encapsulation layer 1 and base layer 2 from flexible materials, and employing a flexible, stretchable, liquid, or transitional conductive material for the sensor body 3, the flexibility, elasticity, and stretchability of the material can be utilized to, on the one hand, enhance the overall mechanical properties of the pressure sensor (e.g., the resilience of the sensor body 3), thereby increasing its service life. Furthermore, it can be used for pressure detection on complex curved surfaces, is less susceptible to damage during non-vertical force measurements, and facilitates the design of a multi-layer sensor body 3.

[0040] Further, refer to Figure 1 and Figure 2The sensor body 3 is sealed between the base layer 2 and the packaging layer 1 by the adhesive 4. When both the base layer 2 and the packaging layer 1 are made of flexible waterproof materials (such as silicone), the use of TPU adhesive 4 can achieve the waterproof sealing function of the entire pressure sensor.

[0041] Further, refer to Figure 3 and Figure 4 The sensor body 3 includes a detection part 31, a wire part 32 and an interface part 33. The wire part 32 includes a first wire segment 321 and multiple second wire segments 322. The detection part 31 and the interface part 33 are also provided with multiple. One end of the multiple detection parts 31 is connected to one end of an interface part 33 through a common first wire segment 321, and the other end of the multiple detection parts 32 is connected to one end of the multiple interface parts 33 through multiple second wire segments 322. All the interface parts 33 are arranged on the same side. The multiple interface parts 33 are arranged on the same side and can be arranged in one place through the detection part 31. At this time, the multiple interface parts 33 only need to use one circuit board, thereby improving space utilization and simplifying the complexity of the circuit.

[0042] In other embodiments of the present invention, reference Figure 5 The sensor body 3 includes a detection part 31, a wire part 32 and an interface part 33. The wire part 32 includes a plurality of second wire segments 322, and the detection part 31 and the interface part 33 are also provided with a plurality of them. The two ends of the multiple detection parts 31 are respectively connected to one end of the interface part 33 through the second wire segment 322. All the interface parts 33 are arranged on the same side. In actual use, sharing the first wire segment 321 will cause the sensors between different channels to be subjected to the same overall extrusion force, thereby affecting the sensor value. After removing the first wire segment 321, the difference between different channels can be amplified, resulting in obvious directionality, making the sensor value more accurate.

[0043] Optionally, the detection portion 31 , the wire portion 32 and the interface portion 33 are made of the same flexible, stretchable, liquid or transitional conductive material, such as liquid metal conductive ink, to improve consistency.

[0044] Optionally, the line width of the detection portion 31 is set to be less than or equal to the line width of the wire portion 32 and less than or equal to the line width of the interface portion 33 .

[0045] Further, refer to Figure 3 and Figure 4 When the wire portion 32 includes the first wire segment 321 , the portion where the first wire segment 321 is connected to the detection portion 31 is in an arc shape or a straight line shape as a whole.

[0046] Further, refer to Figure 3-Figure 5, the detection part 31 is in the shape of a long line or an S-shaped line as a whole. When the area of ​​the detection part 31 is constant, the smaller the wire diameter of the detection part 31, the greater the resistance change rate under unit pressure. The longer the line, the more forward accumulation is generated when it is subjected to pressure, resulting in a more significant change in the electrical signal. Therefore, the smaller the wire diameter of the detection part 31 and the longer the total line length, the more sensitive the pressure detection. In addition, the larger the area occupied by the detection part 31 in the total space, the wider the detection range.

[0047] Furthermore, when the pressure sensor utilizes a multi-layer sensor body 3, the multiple sensor bodies 3 can be a combination of capacitive and resistive sensors, or all capacitive or all resistive sensors. In the case of a capacitive sensor, the dielectric layer between the upper and lower plates is made of silicone, and the upper and lower electrode plates are filled with liquid metal as the electrode material. While functioning as a capacitive sensor, each plate can also function as a resistive sensor to detect resistance changes, thereby simultaneously obtaining resistance and capacitance data for pressure, thereby achieving higher processing accuracy.

[0048] In some embodiments of the present invention, reference Figure 3-Figure 9 , the pressure sensor can adopt an inclined grid-shaped multi-layer sensor body structure design. Specifically, the multi-layer sensor body includes at least one group of a left tilt sensor body 41 and a right tilt sensor body 42. The left tilt sensor body 41 and the right tilt sensor body 42 are axially symmetrically arranged on the same projection plane. The detection parts 31 corresponding to the left tilt sensor body 41 and the right tilt sensor body 42 are both set at an angle to the horizontal direction. And the interface parts 33 of the left tilt sensor body 41 and the right tilt sensor body 42 overlap. In order to make the interface part 33 overlap, the detection part 31 and the second wire segment 322 are set at an angle. Through the axially symmetrical setting, matrix detection is realized and the number of detection points is expanded. As Figure 5 As shown, there are (9-1)*(9-1)=8*8=64 detection points.

[0049] Preferably, the detection portion 31 is in an S-shaped linear shape as a whole, so that the detection portion 31 of the sensor body occupies a higher utilization rate of the total area and has a wider detection range.

[0050] Optionally, the angle between the detection portion 31 corresponding to the left tilt sensor body 41 and the right tilt sensor body 42 and the horizontal direction is 45°.

[0051] In other embodiments of the present invention, reference Figure 3 、 Figure 4 and Figure 10The pressure sensor adopts a multi-layer sensor body structure design with independent layers of wires in a grid pattern. Specifically, the multi-layer sensor body includes at least one group of horizontal sensor bodies 51 and vertical sensor bodies 52. Each group includes a horizontal sensor body 51 and a vertical sensor body 52. ​​The detection parts 31 of the horizontal sensor body 51 and the vertical sensor body 52 intersect vertically. The second wire segment 322 of the horizontal sensor body 51 is flipped together with the corresponding interface part 33, so that the interface part 33 corresponding to the horizontal sensor body 51 overlaps with the interface part 33 corresponding to the vertical sensor body 52 ( Figure 10 (The figure shows the state before flipping.) After flipping, the second conductor segment 322 of the horizontal sensor body 51 becomes an independent layer, meaning a silicone isolation layer is provided between the detection portion 31 of the horizontal sensor body 51 and the second conductor segment 322 of the flipped horizontal sensor body 51. Flipping the second conductor segment 322 of the horizontal sensor body 51 not only separates the second conductor segment 322 from the detection portion 31 but also eliminates the need for the second conductor segment 322 to occupy the independent layer of the detection portion 31, thereby increasing the occupancy rate of the detection area of ​​the horizontal sensor body 51. Furthermore, after flipping, the interface portions 33 of the horizontal and vertical sensor bodies 51 and 52 overlap, requiring only a single circuit board, improving space utilization and simplifying circuit complexity.

[0052] Furthermore, in order to prevent the transverse sensor body 51 from being disconnected at the folding portion between the detection portion 31 and the second wire segment 322 , the isolation layer between the detection portion 31 and the second wire segment 322 should completely cover both.

[0053] Preferably, the detection portion 31 is generally S-shaped. This, on the one hand, maximizes the utilization of the detection portion 31 within the sensor body, extending the detection range. On the other hand, when pressure is applied to the detection portion 31, the effect on the overall resistance is negligible compared to a long linear shape, resulting in more sensitive detection.

[0054] In some further embodiments of the present invention, Figure 3 and Figure 4 as well as Figure 11 and Figure 12The pressure sensor adopts a multi-layer sensor body structure design with a horizontal trapezoidal overlapping grid. Specifically, the multi-layer sensor body includes at least one group of horizontal sensor bodies 51 and vertical sensor bodies 52. Each group includes two horizontal sensor bodies 51 and one vertical sensor body 52. ​​The interface parts 33 of the two horizontal sensor bodies 51 are arranged on the same side as the interface parts 33 of the vertical sensor body 52. ​​The detection parts 31 of the two horizontal sensor bodies 51 are both arranged in a trapezoidal shape and the detection parts 31 of the two horizontal sensor bodies 51 can be spliced ​​into a complete horizontal layer. That is, the detection parts 31 of the two horizontal sensor bodies 51 do not form a complete row, but turn into a stepped shape in the middle, but can be combined into a complete horizontal row by overlapping the detection parts 31 of the same row of another layer that is symmetrical on the left and right.

[0055] In some further embodiments of the present invention, reference Figure 3 and Figure 4 as well as Figure 13 and Figure 14 The pressure sensor adopts an axisymmetric multi-layer sensor body structure design. Specifically, the multi-layer sensor body includes at least one group of a vertical sensor body 61, a left tilt sensor body 41 and a right tilt sensor body 42. The length direction of the detection section 311 of the vertical sensor body 61 is perpendicular to the horizontal line and is arranged symmetrically on the left and right sides, so that left-right symmetrical pressure perception can be obtained. The interface part 33 of the left tilt sensor body 41 and the right tilt sensor body 42 overlaps with the interface part 33 of the vertical sensor body 61. And the left tilt sensor body 41 and the right tilt sensor body 42 are arranged axially symmetrically. After combining the left tilt sensor body 41 and the right tilt sensor body 42 with the vertical sensor body 61, left-right symmetrical pressure perception can be obtained on the basis of high precision.

[0056] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the present invention. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical principles disclosed herein are intended to be covered by the claims of the present invention.

Claims

1. A pressure sensor, characterized in that: The pressure sensor includes an encapsulation layer, a base layer, and at least one sensor body fixedly arranged between the encapsulation layer and the base layer. The encapsulation layer and the base layer are both made of flexible materials. The sensor body is made of flexible, stretchable, liquid or transitional conductive material. When the sensor body is multi-layered, the multi-layer sensor bodies are arranged at intervals up and down, and an isolation layer is provided between two adjacent layers of the sensor bodies. The isolation layer is made of flexible material.

2. The pressure sensor according to claim 1, wherein An adhesive is further provided between the base layer and the packaging layer, and the sensor body is sealed between the base layer and the packaging layer by the adhesive.

3. The pressure sensor according to claim 1, wherein The sensor body includes a detection part, a wire part and an interface part; The wire portion includes a first wire segment and multiple second wire segments, and the detection portion and the interface portion are also provided with multiple ones, one end of the multiple detection portions is connected to one end of the interface portion through a common first wire segment, and the other ends of the multiple detection portions are connected to one end of the multiple interface portions through multiple second wire segments, one by one, and all the interface portions are provided on the same side; or The wire portion includes multiple second wire segments, and the detection portion and the interface portion are also provided with multiple ones. The two ends of the multiple detection portions are respectively connected to one end of the interface portion through the second wire segments, and all the interface portions are arranged on the same side.

4. The pressure sensor according to claim 3, characterized in that The encapsulation layer and the base layer are made of the same flexible material. When the isolation layer is included, the isolation layer is made of the same flexible material as the encapsulation layer and the base layer. The detection part, the wire part and the interface part are made of the same flexible, stretchable, liquid or transitional conductive material.

5. The pressure sensor according to claim 3, wherein The line width of the detection part is less than or equal to the line width of the conductor part and less than or equal to the line width of the interface part; The detection portion is in the shape of a long line or an S-shaped line as a whole; When the wire portion includes the first wire segment, a portion of the first wire segment connected to the detection portion is in an arc shape or a straight line shape as a whole.

6. The pressure sensor according to claim 3, characterized in that When the pressure sensor adopts a multi-layer sensor body, the plurality of sensor bodies may be a combination of capacitive sensors and resistive sensors arranged at intervals, or all of the sensor bodies may be capacitive sensors or resistive sensors.

7. The pressure sensor according to claim 3, wherein: The pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of a left-tilt sensor body and a right-tilt sensor body. The left-tilt sensor body and the right-tilt sensor body are axially symmetrically arranged on the same projection plane. The detection parts corresponding to the left-tilt sensor body and the right-tilt sensor body are both arranged at an angle to the horizontal direction, and the interface parts of the left-tilt sensor body and the right-tilt sensor body overlap.

8. The pressure sensor according to claim 3, wherein: The pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of a horizontal sensor body and a vertical sensor body. The detection parts of the horizontal sensor body and the vertical sensor body intersect vertically. The second wire segment of the horizontal sensor body is flipped together with the corresponding interface part, so that the interface part corresponding to the horizontal sensor body overlaps with the interface part corresponding to the vertical sensor body. After being flipped, the second wire segment of the horizontal sensor body serves as an independent layer.

9. The pressure sensor according to claim 3, wherein: The pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of two horizontal sensor bodies and one vertical sensor body. The interface parts of the two horizontal sensor bodies are arranged on the same side as the interface part of the vertical sensor body. The detection parts of the two horizontal sensor bodies are both arranged in a trapezoidal shape and the detection parts of the two horizontal sensor bodies can be spliced ​​into a complete horizontal layer.

10. The pressure sensor according to claim 3, wherein The pressure sensor includes multiple layers of sensor bodies, and the multiple layers of sensor bodies include at least one group of a vertical sensor body, a left-tilted sensor body and a right-tilted sensor body. The length direction of the detection part of the vertical sensor body is perpendicular to the horizontal line and is symmetrically arranged on the left and right sides. The interface parts of the left-tilted sensor body and the right-tilted sensor body overlap with the interface parts of the vertical sensor body, and the left-tilted sensor body and the right-tilted sensor body are axially symmetrically arranged.

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