Foldable pressure sensor

Abstract

The utility model relates to the technical field of pressure sensors, in particular to a foldable pressure sensor. The utility model discloses a foldable pressure sensor which comprises a first conductive fabric, a second conductive fabric and a third conductive fabric which are attached together through hot pressing, the first conductive fabric is attached to the second conductive fabric through a first adhesive layer, and the second conductive fabric is attached to the third conductive fabric through a second adhesive layer. According to the foldable pressure sensor provided by the invention, a special laminated structure of the first conductive cloth, the first adhesive layer, the second conductive cloth, the second adhesive layer and the third conductive cloth is constructed, so that when the sensor is folded, all layers of materials can cooperatively deform, and an internal conductive structure of the sensor cannot be influenced.

Description

Technical Field

[0001] The present application relates to the technical field of pressure sensors, and particularly to a foldable pressure sensor. Background Art

[0002] Existing pressure sensors for human detection have their core in sensing external pressure changes through the deformation of piezoresistive materials or changes in contact area, and then converting such changes into electrical signal output. In terms of material composition, these sensors use plastic films as substrates, print electrodes on the films, and sandwich special piezoresistive materials between the upper and lower layers of electrodes.

[0003] Therefore, since the existing pressure sensors use plastic films as substrates and the piezoresistive materials may lack sufficient flexibility and elasticity, they cannot withstand folding or bending without affecting their performance. Once the pressure sensor is folded, it may cause electrode breakage, deformation or breakage of the piezoresistive materials, thus seriously affecting the accuracy and reliability of the sensor.

[0004] Moreover, due to material limitations, the performance of existing pressure sensors may be severely affected when facing complex usage environments (such as scenarios that require frequent folding or bending), restricting the use of the sensors in specific application scenarios.

[0005] For this reason, the present application provides a foldable pressure sensor. Utility Model Content

[0006] In order to overcome the deficiencies of the prior art, the present application provides a foldable pressure sensor. By constructing a special laminated structure of a first conductive cloth - a first adhesive layer - a second conductive cloth - a second adhesive layer - a third conductive cloth, when the sensor is folded, each layer of material can deform synergistically without affecting its internal conductive structure.

[0007] The technical solution adopted by the present application to solve its technical problems is as follows:

[0008] A foldable pressure sensor includes a first conductive cloth, a second conductive cloth, and a third conductive cloth that are thermally pressed together. The first conductive cloth is adhered to the second conductive cloth through a first adhesive layer, and the second conductive cloth is adhered to the third conductive cloth through a second adhesive layer.

[0009] In some embodiments, the surface conductivity of the first conductive cloth and the third conductive cloth is < 10 Ω.

[0010] In some embodiments, the materials of the first conductive cloth and the third conductive cloth are silver-plated fiber textile fabrics.

[0011] In some embodiments, the thicknesses of the first adhesive layer and the second adhesive layer are 0.2 - 0.3 mm.

[0012] In some embodiments, through slots are provided on both the first adhesive layer and the second adhesive layer.

[0013] In some embodiments, the first adhesive layer and the second adhesive layer are hot melt adhesive layers.

[0014] In some embodiments, the surface conductivity of the second conductive cloth > 1 KΩ.

[0015] In some embodiments, the material of the second conductive cloth is a fiber cloth plated with a conductive material.

[0016] In some embodiments, pins are crimped to one end of the first conductive cloth and one end of the third conductive cloth.

[0017] In some embodiments, the first conductive cloth, the second conductive cloth, and the third conductive cloth have the same size.

[0018] The beneficial effects of this application are as follows:

[0019] 1. For the foldable pressure sensor described in this application, by constructing a special laminated structure of the first conductive cloth - the first adhesive layer - the second conductive cloth - the second adhesive layer - the third conductive cloth, when the sensor is folded, the materials of each layer can deform synergistically without affecting its internal conductive structure.

[0020] 2. For the foldable pressure sensor described in this application, when there is no pressure acting on the sensor, the first conductive cloth and the second conductive cloth, and the second conductive cloth and the third conductive cloth are separated by a hot melt adhesive film and are basically not in contact, so the contact resistance of the pressure sensor is small; when an external pressure acts on the sensor, the first conductive cloth and the second conductive cloth, and the second conductive cloth and the third conductive cloth are in contact through the through slots, and the contact area increases, resulting in an increase in the contact resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The following further describes this application with reference to the drawings and embodiments.

[0022] Figure 1 is a schematic structural diagram of a foldable pressure sensor described in this application;

[0023] Among them: 1. First conductive cloth; 2. Second conductive cloth; 3. Third conductive cloth; 4. First adhesive layer; 5. Second adhesive layer; 6. Through slot; 7. Pin. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The concept, specific structure, and technical effects of this application will be clearly and completely described below in combination with embodiments and the accompanying drawings to fully understand the purpose, features, and effects of this application. Obviously, the described embodiments are only a part of the embodiments of this application, rather than all of them. Based on the embodiments of this application, other embodiments obtained by those skilled in the art without creative efforts all fall within the scope of protection of this application. In addition, all connection / linkage relationships involved in the patent do not simply refer to direct connection of components, but refer to more optimal connection structures that can be formed by adding or reducing connection accessories according to specific implementation situations. Each technical feature in the creation of this application can be interactively combined without conflicting with each other.

[0025] As Figure 1 shown, a foldable pressure sensor includes a first conductive cloth 1, a second conductive cloth 2, and a third conductive cloth 3 that are thermally pressed together. The first conductive cloth 1 is adhered to the second conductive cloth 2 through a first adhesive layer 4, and the second conductive cloth 2 is adhered to the third conductive cloth 3 through a second adhesive layer 5.

[0026] In the above technical solution, a special laminated structure is adopted, that is, it is formed by thermally pressing the first conductive cloth, the first adhesive layer, the second conductive cloth, the second adhesive layer, and the third conductive cloth. This lamination method enables the materials of each layer to deform synergistically when the sensor is subjected to external pressure, effectively avoiding problems such as electrode fracture and piezoresistive material deformation caused by folding or bending, and solving the problem of performance degradation of the prior art in the folded state.

[0027] In some embodiments, the surface conductivity of the first conductive cloth 1 and the third conductive cloth 3 is less than 10 Ω. The materials of the first conductive cloth 1 and the third conductive cloth 3 are silver-plated fiber textile fabrics.

[0028] In the above technical solution, the materials of the first conductive cloth 1 and the third conductive cloth 3 are silver-plated fiber textile fabrics. The silver plating treatment endows the fibers with excellent electrical conductivity, and at the same time, the structure of the textile fabric endows it with excellent flexibility and weavability. The surface conductivity of the first conductive cloth 1 and the third conductive cloth 3 is less than 10 Ω. During the transmission of electrical signals, the resistance is small and the energy loss is low, which is beneficial to improving the sensitivity and response speed of the sensor.

[0029] At the same time, due to the high flexibility of the silver-plated fiber textile fabric, it can well adapt to complex usage environments, such as scenarios that require frequent folding or bending in wearable devices, curved screens, etc., thus greatly expanding the application fields of the sensor. Moreover, the silver-plated fiber textile fabric with low conductivity reduces signal attenuation and noise interference caused by excessive material resistance while ensuring good electrical conductivity.

[0030] In some embodiments, the thicknesses of the first adhesive layer 4 and the second adhesive layer 5 are 0.2 - 0.3 mm.

[0031] Specifically, the thicknesses of the first adhesive layer 4 and the second adhesive layer 5 are precisely controlled within the range of 0.2 - 0.3 mm. Then, a hot melt adhesive material with excellent flexibility is selected, effectively enhancing the anti - folding property of the sensor. The thickness range of 0.2 - 0.3 mm not only ensures sufficient bonding strength but also endows the sensor with good flexibility, enabling it to maintain stable performance after multiple foldings.

[0032] In some embodiments, through - slots 6 are provided on both the first adhesive layer 4 and the second adhesive layer 5. The first adhesive layer 4 and the second adhesive layer 5 are hot melt adhesive layers.

[0033] Specifically, due to material limitations, in traditional pressure sensors, when facing folding or bending, the electrodes and piezoresistive materials are prone to breakage or deformation, seriously affecting the accuracy and reliability of the sensor. The design of the through - slots 6 allows the materials of each layer to undergo local deformation through the through - slots during folding without generating overall stress concentration, thereby enhancing the foldability and durability of the sensor. The specific size and dimensions of the through - slots 6 can be set according to actual needs.

[0034] Moreover, when an external pressure acts on the sensor, the first conductive cloth and the second conductive cloth, and the second conductive cloth and the third conductive cloth are in contact through the through - slots, and the contact area increases significantly, resulting in an increase in contact resistance. This change in contact area can more accurately reflect the change in external pressure, thereby improving the sensitivity of pressure sensing.

[0035] Specifically, hot melt adhesive is selected as the adhesive layer material because hot melt adhesive has good adhesiveness, flexibility, and temperature resistance; during the hot pressing process, the hot melt adhesive can quickly melt and tightly bond with the conductive cloth; after cooling, the hot melt adhesive can maintain a certain elasticity and toughness to meet the folding and bending requirements of the sensor.

[0036] Therefore, a hot melt adhesive layer is selected as the connection layer between the first conductive cloth, the second conductive cloth, and the third conductive cloth, and the materials of each layer are firmly bonded together through a hot melt process to form an integral structure. This connection method not only ensures the overall strength of the sensor but also avoids the stress concentration problems that may be brought about by traditional welding or bonding methods.

[0037] Moreover, when there is no pressure acting, the hot melt adhesive layer plays an isolation role, preventing unnecessary contact between the first conductive cloth and the second conductive cloth, and the second conductive cloth and the third conductive cloth; when an external pressure acts, the through - slots on the hot melt adhesive layer allow the conductive cloths to be in contact through the through - slots to achieve the conduction function.

[0038] In some embodiments, the surface conductivity of the second conductive cloth > 1 KΩ, and the material of the second conductive cloth 2 is a fiber cloth plated with a conductive material.

[0039] Specifically, the surface conductivity of the second conductive cloth > 1 KΩ, which not only ensures good electrical conductivity but also avoids signal interference and noise problems caused by excessive conductivity.

[0040] Moreover, using a fiber cloth plated with a conductive material as the material of the second conductive cloth, this material has good flexibility and elasticity, and can adapt to various complex deformation scenarios, including frequent folding and bending. At the same time, the structural characteristics of the fiber cloth make it not easy to generate cracks or fractures during use, thus extending the service life of the sensor.

[0041] Therefore, the second conductive cloth has appropriate conductivity and excellent material properties, enabling the sensor to more accurately reflect the change in pressure when subjected to external pressure and convert it into corresponding electrical signal output. This process not only improves the detection sensitivity but also ensures the accuracy and reliability of the data. The second conductive cloth made of fiber cloth can still maintain good electrical conductivity and structural integrity after experiencing multiple folds and bends, effectively avoiding the problem of sensor performance degradation caused by material aging or damage.

[0042] In some embodiments, pins 7 are crimped to one end of the first conductive cloth 1 and one end of the third conductive cloth 3.

[0043] Specifically, the pins 7 are respectively crimped to one end of the first conductive cloth 1 and the third conductive cloth 3, usually located at the edge of the sensor for easy connection to the external circuit; in practical applications, the position, number, shape, and size of the pins 7 can be adjusted according to needs to meet different connection requirements; the material of the pins should have high electrical conductivity, corrosion resistance, and mechanical strength, usually made of metal materials such as copper and gold-plated copper to ensure good electrical conductivity and stability.

[0044] In some embodiments, the first conductive cloth 1, the second conductive cloth 2, and the third conductive cloth 3 have the same size.

[0045] Specifically, the conductive cloth layer structure with the same size enables the pressure to be evenly distributed among the layers when the sensor is subjected to external pressure, reducing the risk of performance degradation or damage caused by local stress concentration, and improving the measurement accuracy and long-term durability of the sensor.

[0046] For the foldable pressure sensor described in this application, when there is no pressure acting, the first conductive cloth and the second conductive cloth, and the second conductive cloth and the third conductive cloth are separated by a hot melt adhesive film and have basically no contact, so the contact resistance of the pressure sensor is small;

[0047] When an external pressure acts on the sensor, the first conductive cloth and the second conductive cloth, and the second conductive cloth and the third conductive cloth are in contact through the slot, and the contact area increases, resulting in an increase in the contact resistance.

[0048] For the pressure sensor, the change in the contact resistance can be detected by a circuit and converted into an electrical signal output, thereby realizing the detection of pressure.

[0049] Cutting: Cut the first conductive cloth, the hot melt adhesive film, the second conductive cloth, and the third conductive cloth into sheets of required sizes, and note that the external length and width dimensions of the three materials of the first conductive cloth, the second conductive cloth, and the third conductive cloth are kept the same, and a slot is formed by opening a hole in the middle of the hot melt adhesive film.

[0050] Laminating: Stack the materials in the order of "first conductive cloth - hot melt adhesive film - second conductive cloth - hot melt adhesive film - third conductive cloth".

[0051] Hot pressing: Use a flat hot pressing forming machine to hot press at a temperature of 135 °C to closely bond the materials.

[0052] Cutting: Use a die to cut out the final required outer contour of the hot-pressed semi-finished product to ensure that the edges are smooth and beautiful.

[0053] Trimming the lead electrodes: Separate the conductive cloth on the upper and lower sides of the lead electrodes, and reserve the conductive cloth (the first conductive cloth, the third conductive cloth) at specific positions as the lead electrodes, and cut off the redundant parts.

[0054] Crimping the lead terminal: Crimp a piercing type cold press terminal on the two separated lead electrodes on the left and right to be used as the pins of the sensor.

[0055] For the foldable pressure sensor of the present application, when the pressure sensor is folded and bent, the surface roughness of the laminated structure and its own elasticity will not be changed, so folding, bending and kneading will not affect its pressure detection performance.

[0056] The foldable pressure sensor of the present application has been tested. The sensor is arbitrarily folded and kneaded on the hand for 5 minutes and then unfolded and flattened. The pressure detection performance of the sensor will not change significantly.

[0057] The above is a specific description of the preferred embodiment of the present application, but the present invention is not limited to the described embodiment. Those skilled in the art can also make various equivalent deformations or substitutions without departing from the spirit of the present application, and these equivalent deformations or substitutions are all included within the scope defined by the claims of the present application.

Claims

1. A foldable pressure sensor, characterized in that: The invention comprises a first conductive cloth (1), a second conductive cloth (2) and a third conductive cloth (3) which are bonded together by heat pressing, wherein the first conductive cloth (1) is bonded to the second conductive cloth (2) via a first adhesive layer (4), and the second conductive cloth (2) is bonded to the third conductive cloth (3) via a second adhesive layer (5).

2. The pressure sensor according to claim 1, characterized in that: The surface conductivity of the first conductive cloth (1) and the third conductive cloth (3) is less than 10Ω.

3. The pressure sensor according to claim 1, characterized in that: The first conductive cloth (1) and the third conductive cloth (3) are made of silver-plated fiber textile cloth.

4. The pressure sensor according to claim 1, characterized in that: The thickness of the first adhesive layer (4) and the second adhesive layer (5) is 0.2-0.3 mm.

5. The pressure sensor according to claim 1, characterized in that: The first adhesive layer (4) and the second adhesive layer (5) are both provided with through grooves (6).

6. The pressure sensor according to claim 1, characterized in that: The first adhesive layer (4) and the second adhesive layer (5) are hot melt adhesive layers.

7. The pressure sensor according to claim 1, characterized in that: The surface conductivity of the second conductive cloth (2) is greater than 1 KΩ.

8. The pressure sensor according to claim 1, characterized in that: The second conductive cloth (2) is made of fiber cloth coated with conductive material.

9. The pressure sensor according to claim 1, characterized in that: One end of the first conductive cloth (1) and one end of the third conductive cloth (3) are both crimped with pins (7).

10. The pressure sensor according to claim 1, characterized in that: The first conductive cloth (1), the second conductive cloth (2) and the third conductive cloth (3) are of the same size.

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