CN115127703A - Clothing, piezoelectric fabric sensor and manufacturing method thereof - Google Patents

Abstract

The present invention provides a garment, a piezoelectric fabric sensor and a manufacturing method thereof, wherein the piezoelectric fabric sensor comprises two conductive yarn layers arranged oppositely and an expanded yarn layer arranged between the two conductive yarn layers , an insulating yarn layer is arranged between each of the conductive yarn layers and the expanded yarn layer, a PVDF monofilament is threaded between the two conductive yarn layers, and the PVDF monofilament runs through the two conductive yarn layers. The insulating yarn layer and the expanded yarn layer are connected to the two conductive yarn layers, and electrodes are installed on both the conductive yarn layers. The present invention replaces the conventional piezoelectric layer by PVDF monofilament. The PVDF monofilament is soft and has strong bendability, and is more suitable for use in piezoelectric fabric sensors. The piezoelectric fabric sensors are all woven from fabrics, and have good air permeability and expandability. The yarn layer provides elasticity to the piezoelectric fabric sensor, providing effective space through contact separation, thereby enhancing piezoelectric performance.

Description

Clothing, piezoelectric fabric sensor and method of making the same

technical field

The invention relates to the technical field of sensors, in particular to a garment, a piezoelectric fabric sensor and a manufacturing method thereof.

Background technique

With the rapid development of smart wearable devices in domestic and foreign markets, the sensors on smart wearable devices need to be upgraded urgently. The intervention treatment and life cycle health management of smart wearable fabric sensor devices based on medical health data will become the future of smart wearable devices. The key word for development, smart wearable devices are also becoming a new technology to change the medical system and human health, but traditional sensors are mostly solid-state sensor layer structures, which are hard and not easy to bend, and cannot be used in smart wearable devices.

SUMMARY OF THE INVENTION

The main purpose of the present invention is to provide a garment, a piezoelectric fabric sensor and a manufacturing method thereof, aiming at solving the problem that the existing sensor has high hardness and is not easy to bend.

In order to achieve the above object, the present invention provides a piezoelectric fabric sensor, comprising two conductive yarn layers disposed opposite to each other and an expanded yarn layer disposed between the two conductive yarn layers, each of the conductive yarn layers. An insulating yarn layer is arranged between the layer and the expanded yarn layer, and PVDF monofilament is passed between the two conductive yarn layers, and the PVDF monofilament runs through the expanded yarn layer and the two conductive yarn layers. The insulating yarn layer is connected to the two conductive yarn layers, and electrodes are installed on the two conductive yarn layers.

Preferably, the PVDF monofilaments are alternately interspersed between the two conductive yarn layers.

Preferably, the conductive yarn layer is woven from silver-plated conductive nylon filaments.

Preferably, the specification of the silver-plated conductive nylon filament is 140D/48F, and the resistance value is 4-6Ω/cm.

Preferably, the insulating yarn layer is woven from polyester yarn.

Preferably, the specification of the polyester yarn is 210D/3.

Preferably, the thickness of the expanded yarn layer is 2 mm˜4 mm; and/or, the PVDF monofilament is a circular monofilament with a diameter of 0.08 mm˜0.15 mm.

The present invention also provides a garment, wherein the above-mentioned piezoelectric fabric sensor is applied to the garment.

The present invention also provides a method for making a piezoelectric fabric sensor, which is used to make the above-mentioned piezoelectric fabric sensor, comprising the following steps:

weaving to obtain two layers of the conductive yarn;

The insulating yarn layer is obtained by weaving one side of each of the conductive yarn layers toward the other of the conductive yarn layers;

Weaving between the two insulating yarn layers to obtain an expanded yarn layer;

weaving the PVDF monofilament between the two conductive yarn layers, and making the PVDF monofilament penetrate the expanded yarn layer and the two insulating yarn layers;

Two of the electrodes are connected to two of the conductive yarn layers, respectively.

Preferably, the step of weaving PVDF monofilaments between the two conductive yarn layers includes:

The PVDF monofilaments are inserted from one of the conductive yarn layers in an alternating manner, and sequentially penetrated through one of the insulating yarn layers, the expanded yarn layer and the other insulating yarn layer, and then correspondingly from the insulating yarn layer. The other layer of the conductive yarn is pierced out.

In the technical solution of the present invention, the conductive yarn layer is used as the outermost layer of the piezoelectric fabric sensor, and an insulating yarn layer is arranged inside the conductive yarn layer to relatively insulate the surface of the conductive yarn layer to prevent pressure shock The deformation of the piezoelectric fabric sensor leads to direct contact between the two conductive yarn layers, forming a short circuit, which affects the detection of the piezoelectric fabric sensor. There is also an expanded yarn layer between the insulating yarn layers. The expanded yarn layer provides elasticity for the piezoelectric fabric sensor, so that the piezoelectric fabric sensor can be restored in time after deformation, and provides an effective space through contact separation, thereby improving piezoelectric performance. ;Long-term use will cause the conductive yarn layer to be worn and the thread will become loose, and the loose thread may connect the two conductive yarn layers and cause a short circuit. Therefore, the expanded yarn layer also strengthens the piezoelectric fabric sensor and isolates the two conductive yarn layers. The role of the PVDF monofilament replaces the conventional piezoelectric layer and conducts two conductive yarn layers. The PVDF monofilament is soft and has strong bendability, which is more suitable for use in fabric sensors.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained according to the structures shown in these drawings without creative efforts.

1 is a schematic structural diagram of a piezoelectric fabric sensor according to a first embodiment of the present invention;

FIG. 2 is a schematic diagram of the principle of the piezoelectric fabric sensor according to the second embodiment of the present invention;

3 is a schematic structural diagram of a piezoelectric fabric sensor according to a third embodiment of the present invention;

FIG. 4 is a schematic flowchart of a manufacturing method of a piezoelectric fabric sensor according to a fourth embodiment of the present invention;

FIG. 5 is a schematic flowchart of a manufacturing method of a piezoelectric fabric sensor according to a fifth embodiment of the present invention.

Description of reference numbers:

label name label name 1 Piezoelectric Fabric Sensor twenty one first insulating yarn layer 10 conductive yarn layer twenty two second insulating yarn layer 11 first conductive yarn layer 30 expanded yarn layer 12 second conductive yarn layer 40 PVDF monofilament 20 insulating yarn layer 50 electrode

The object realization, functional features and advantages of the present invention will be further described with reference to the accompanying drawings in conjunction with the embodiments.

Detailed ways

The technical solutions in this embodiment will be clearly and completely described below with reference to the drawings in this embodiment. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be noted that all directional indications (such as up, down, left, right, front, back...) in this embodiment are only used to explain the relative relationship between various components under a certain posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly.

In addition, descriptions such as "first", "second", etc. in the present invention are only for descriptive purposes, and should not be construed as indicating or implying their relative importance or implicitly indicating the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise expressly and specifically defined.

In the present invention, unless otherwise expressly specified and limited, the terms "connected", "fixed" and the like should be understood in a broad sense, for example, "fixed" may be a fixed connection, a detachable connection, or an integrated; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be an internal communication between two elements or an interaction relationship between the two elements, unless otherwise explicitly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that the combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention. It should be understood that the specific embodiments described herein are only used to explain the present invention, but not to limit the present invention.

Referring to FIG. 1, the present invention provides a piezoelectric fabric sensor 1, comprising two conductive yarn layers 10 disposed opposite to each other and an expanded yarn layer 30 disposed between the two conductive yarn layers 10. Each conductive yarn layer An insulating yarn layer 20 is provided between the layer 10 and the expanded yarn layer 30, and a PVDF monofilament 40 is passed between the two conductive yarn layers 10. The PVDF monofilament 40 penetrates the expanded yarn layer 30 and the two insulating yarns. The yarn layer 20 is connected, and the two conductive yarn layers 10 are connected, and electrodes 50 are installed on the two conductive yarn layers 10 .

Referring to FIG. 1, for ease of understanding, the two conductive yarn layers 10 are described as a first conductive yarn layer 11 and a second conductive yarn layer 12, respectively, and the two insulating yarn layers 20 are described as a first insulating yarn layer, respectively The yarn layer 21 and the second insulating yarn layer 22. The present invention provides a piezoelectric fabric sensor 1, which includes a first conductive yarn layer 11, a second conductive yarn layer 12, and a first conductive yarn layer 12 disposed opposite to each other. The expanded yarn layer 30 between the thread layer 11 and the second conductive yarn layer 12, the first insulating yarn layer 21 is provided between the first conductive yarn layer 11 and the expanded yarn layer 30, and the second conductive yarn A second insulating yarn layer 22 is arranged between the layer 12 and the expanded yarn layer 30, and a PVDF monofilament 40 is passed between the first conductive yarn layer 11 and the second conductive yarn layer 12, and the PVDF monofilament 40 runs through The first insulating yarn layer 21, the second insulating yarn layer 22 and the expanded yarn layer 30 connect the first conductive yarn layer 11 and the second conductive yarn layer 12, and the first conductive yarn layer 11 and the The second conductive yarn layers 12 are each mounted with electrodes 50 .

Referring to FIG. 1, a piezoelectric fabric sensor 1 generally includes a first conductive yarn layer 11, a first insulating yarn layer 21, an expanded yarn layer 30, a second insulating yarn layer 22, a The two conductive yarn layers 12 and the PVDF monofilament 40 interposed between the first conductive yarn layer 11 and the second conductive yarn layer 12 constitute a three-dimensional sensor.

In the technical solution of the present invention, the conductive yarn layer 10 is used as the outermost layer of the piezoelectric fabric sensor 1, and the insulating yarn layer 20 is arranged inside the conductive yarn layer 10, and the surface of the conductive yarn layer 10 is relatively insulated. , to prevent the deformation of the piezoelectric fabric sensor 1 under pressure shock, causing the first conductive yarn layer 11 and the second conductive yarn layer 12 to directly contact, forming a short circuit and affecting the detection of the piezoelectric fabric sensor 1 . There is also an expanded yarn layer 30 between the insulating yarn layers 20. The expanded yarn layer 30 provides elasticity for the piezoelectric fabric sensor 1, so that the piezoelectric fabric sensor 1 can be restored in time after deformation, and provides an effective space through contact separation, Thereby, the piezoelectric performance is improved; long-term use will cause the conductive yarn layer 10 to be worn and the thread ends will become loose, and the loose thread may connect the first conductive yarn layer 11 and the second conductive yarn layer 12 and cause a short circuit, thus expanding the yarn layer 30 It also plays the role of reinforcing the piezoelectric fabric sensor 1, isolating the first conductive yarn layer 11 and the second conductive yarn layer 12, replacing the conventional piezoelectric layer by PVDF monofilament 40, and conducting the first conductive yarn layer 11. And the second conductive yarn layer 12, the PVDF monofilament 40 is soft and has strong bendability, which is more suitable for the piezoelectric fabric sensor 1. At the same time, the entire piezoelectric fabric sensor 1 is woven from fabric, which can ensure that during the wearing process good air permeability and water vapour permeability.

It should be noted that when pressure is applied on the piezoelectric fabric sensor 1, the charge centers on the intermediate layer PVDF separate to form electric dipoles and the electric dipole moment changes, resulting in the formation of a voltage potential between the electrodes 50, rather than the so-called electric dipole moment. direct transmission. Please refer to Fig. 2, Fig. 2 shows the four states of the work flow of the piezoelectric fabric sensor 1, Fig. 2a: In the initial state and the unperturbed state, the charge centers of cations and anions coincide with each other, and there is no electrode inside the piezoelectric material. phenomenon. Figure 2b: Deformation of the piezoelectric fabric produces negative strain and volume reduction when pressure is applied. The charge centers separate to form electric dipoles and the electric dipole moment changes, resulting in the formation of a voltage potential between the electrodes 50 . If electrode 50 is connected to an external load, the voltage potential will drive electrons to flow through the external circuit to partially shield the voltage potential to a new equilibrium state. Thus, mechanical energy is converted into electrical energy. Figure 2c: When the two conductive fabric electrodes 50 are in full contact, the polarization density reaches a maximum squeeze state. Figure 2d: When the external force is released, the electrons flow back, rebalancing the charge induced by the strain release under short-circuit conditions. If the voltage potential is continuously changed by the phenomenon of reciprocating strain, a stable pulse current will flow through the external circuit.

In one embodiment, the PVDF monofilaments 40 are alternately inserted between the first conductive yarn layer 11 and the second conductive yarn layer 12 . The PVDF monofilaments 40 are alternately interspersed between the first conductive yarn layer 11 and the second conductive yarn layer 12 to make the three-dimensional structure of the piezoelectric fabric sensor 1 stronger, provide more effective support for the sensor, and increase the wear resistance of the sensor and service life.

It can be understood that the number of PVDF monofilaments 40 may be multiple, please refer to FIG. 3 , in a specific embodiment, the number of PVDF monofilaments 40 is four, and the four PVDF monofilaments 40 are spaced at the same distance to pre- Set the angle to pass through the first conductive yarn layer 11 and pass through the second conductive yarn layer 12 at a predetermined angle.

In one embodiment, the conductive yarn layer 10 is woven from silver-plated conductive nylon filaments. The conductive yarn is made of silver-plated conductive nylon filament. The nylon filament has good toughness, high tensile, compressive strength and wear resistance. At the same time, the nylon filament has a low density and is light and thin, and is suitable for use as a piezoelectric fabric sensor 1 The outermost material of the nylon filament is plated with silver to make it conductive. At the same time, the conductive yarn layer 10, as the outermost fabric, needs to be in direct contact with the skin. Prevent skin allergies and infections caused by fabric sensors.

In one embodiment, the specification of the silver-plated conductive nylon filament is 140D/48F, and the resistance value is 4-6Ω/cm. Among them, D is the fineness, 140D is the number of grams of silver-plated conductive nylon filament per 9000m length at a predetermined moisture regain is 140g, and F is the number of strands, which means that the silver-plated conductive nylon filament is composed of 48 strands of filaments. This experiment shows that the use of 140D/48F silver-plated conductive nylon filaments can obtain a softer and more stable conductive yarn layer 10 . The resistance value is 4-6Ω/cm, and selecting a suitable resistance value can enhance the piezoelectric performance of the piezoelectric fabric sensor 1 .

In one embodiment, the expanded yarn layer 30 is woven from polyester yarn. The polyester yarn has high strength, good abrasion resistance, good elasticity, and the elasticity is close to that of wool. Recovery, wrinkle resistance is superior to other fibers, that is, the fabric does not wrinkle and has good dimensional stability, which can ensure that it can meet the function of providing space for separation and contact required by the expanded yarn layer 30

In one embodiment, the insulating yarn layer 20 is woven from polyester yarn. Polyester yarn has high strength and good wear resistance. Polyester molecules are combined by covalent bonds and cannot transmit electrons, so they are also suitable as the material of the insulating yarn layer 20 .

In one embodiment, the size of the polyester yarn is 210D/3. Among them, 210D means that the number of grams of silver-plated conductive nylon filament per 9000m length is 210g at a predetermined moisture regain, and 3 means that it is composed of 3 strands of thin wires. Higher strength and durability can be obtained by using 210D/3 polyester yarn.

In one embodiment, the thickness of the expanded yarn layer 30 is 2 mm˜4 mm; and/or, the PVDF monofilament 40 is a circular monofilament with a diameter of 0.08 mm˜0.15 mm. The expanded yarn layer 30 acts as a buffering thread layer. It is too thin to provide an effective space through contact separation and to isolate the first conductive yarn layer 11 and the second conductive yarn layer 12. Too thick will affect the pressure. Because of the electrical properties, the thickness is set at 2mm to 4mm, preferably 3mm. Selecting a PVDF monofilament 40 with a suitable diameter helps to improve its piezoelectric performance, so the diameter is set to be 0.08mm˜0.15mm, preferably 0.1mm.

The present invention also provides a garment, wherein the above-mentioned piezoelectric fabric sensor 1 is applied to the garment. The specific structure of the piezoelectric fabric sensor 1 refers to the above-mentioned embodiments. Since this garment adopts all the technical solutions of the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here. One more elaboration.

The present invention also provides a method for making a piezoelectric fabric sensor, which is used to make the above-mentioned piezoelectric fabric sensor, comprising the following steps:

S100, weaving to obtain two conductive yarn layers;

S200, knitting the insulating yarn layer on the side of each of the conductive yarn layers facing the other conductive yarn layer;

S300, weaving between the two insulating yarn layers to obtain an expanded yarn layer;

S400, weaving the PVDF monofilament between the two conductive yarn layers, and making the PVDF monofilament penetrate the expanded yarn layer and the two insulating yarn layers;

S500, the two electrodes are respectively connected to the two conductive yarn layers.

Since the manufacturing method adopts all the technical solutions of the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be repeated here.

In one embodiment, the step of weaving PVDF monofilaments between the first conductive yarn layer and the second conductive yarn layer includes:

S410, threading the PVDF monofilaments from one of the conductive yarn layers in an alternating manner, and sequentially passing through one of the insulating yarn layers, the expanded yarn layer and the other of the insulating yarn layers Correspondingly pierces out from another said conductive yarn layer.

PVDF monofilaments are alternately arranged between two conductive yarn layers, which can enhance the stability of the three-dimensional structure and piezoelectric properties, and provide more effective support for the sensor.

Exemplarily, in a specific embodiment, Shima Seiki brand SVR-SP 14G is used for knitting, the density is 14 needles, the machine width is 36 inches (92 cm), and polyester yarn (210D/3) is selected, Silver plated conductive nylon filament (140D/48F), PVDF monofilament (0.1mm) and expanded yarn. In the weaving process, 200 needles are used in the front and rear machine tools, three silver-plated conductive nylon filaments and two polyester yarns are used in the first and second rows, expanded yarns are used in the third row, and each of the fourth to seventh rows is used One PVDF monofilament. The specific weaving steps are as follows:

The first row is knitted with full stitches and loops on the front machine board, without transferring needles (using the No. 2 and No. 3 yarn feeders to simultaneously knit and plating);

Weaving to make a first conductive yarn layer and a first insulating yarn layer;

The second row is knitted with full stitches and loops on the rear machine board, without transferring needles (using No. 5 and No. 6 yarn feeders to knit and plating at the same time);

Weaving to make a second conductive yarn layer and a second insulating yarn layer;

The third row does the yarn clamping action;

Woven into an expanded yarn layer;

For the fourth row, do one-third tuck knitting on the front machine board, and do one-third tuck knitting on the rear machine board at the wrong two-needle position, and cancel the automatic transfer action;

In the fifth row, do tuck knitting at the position of the rear plate corresponding to the front plate of the rear plate in the third row, and do tuck knitting at the position of the front plate corresponding to the rear plate in the third row with two wrong stitches, and cancel the automatic transfer action;

Repeat the action of the fourth row with a wrong stitch in the sixth row;

Repeat the action of the fifth row with one wrong stitch in the seventh row;

The fourth row to the seventh row are crossed with PVDF monofilament;

Return to the first row of actions until the knitting is complete.

The above are only preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Any equivalent structure or equivalent process transformation made by using the contents of the description and drawings of the present invention, or directly or indirectly applied in other related technical fields , are similarly included in the scope of patent protection of the present invention.

Claims (10)

1. The utility model provides a piezoelectricity fabric sensor, its characterized in that, including relative two electrically conductive yarn layers that set up and set up in two inflation yarn layer between the electrically conductive yarn layer, each electrically conductive yarn layer with all be provided with insulating yarn layer between the inflation yarn layer, two wear to be equipped with the PVDF monofilament between the electrically conductive yarn layer, the PVDF monofilament runs through inflation yarn layer and two insulating yarn layer, and with two the electrically conductive yarn layer switches on, two the electrode is all installed to the electrically conductive yarn layer.

2. The piezoelectric fabric sensor of claim 1, wherein the PVDF monofilaments are interleaved between two of the layers of conductive yarn.

3. The piezoelectric fabric sensor of claim 1, wherein the conductive yarn layer is woven from silver plated conductive nylon filaments.

4. The piezoelectric fabric sensor according to claim 3, wherein the silver-plated conductive nylon filament has a specification of 140D/48F and a resistance value of 4-6 Ω/cm.

5. The piezoelectric fabric sensor of claim 1, wherein the insulating yarn layer is woven from polyester yarn.

6. The piezoelectric fabric sensor of claim 5, wherein the polyester yarn gauge is 210D/3.

7. The piezoelectric fabric sensor of any one of claims 1 to 6, wherein the layer of intumescent yarn has a thickness of 2mm to 4 mm; and/or the PVDF monofilament is a round monofilament with the diameter of 0.08-0.15 mm.

8. A garment, characterized in that it is applied with a piezo-electric fabric sensor according to any of claims 1 to 7.

9. A method of manufacturing a piezo-electric textile sensor, for manufacturing a piezo-electric textile sensor according to any of claims 1 to 7, comprising the steps of:

weaving to obtain two conductive yarn layers;

weaving the side, facing to the other conductive yarn layer, of each conductive yarn layer to obtain the insulating yarn layer;

weaving the two insulating yarn layers to obtain the expanded yarn layer;

weaving said PVDF monofilament between two of said layers of conductive yarn and running said PVDF monofilament through said layers of intumescent yarn and two of said layers of insulating yarn;

connecting the two electrodes to the two conductive yarn layers, respectively.

10. The method of making a piezoelectric fabric sensor according to claim 9, wherein said step of weaving PVDF monofilament between two layers of conductive yarn and running said PVDF monofilament through said layer of intumescent yarn and two layers of insulating yarn comprises:

and penetrating the PVDF monofilaments in an alternating mode from one conductive yarn layer, sequentially penetrating one insulating yarn layer, the expanded yarn layer and the other insulating yarn layer, and correspondingly penetrating out of the other conductive yarn layer.

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