KR20210046094A - Body pressure sensor having a multi-layer structure - Google Patents

Abstract

The present invention relates to a body pressure sensor having a multilayer structure in the form of a thin fabric that can be applied to a blanket or a mattress cover. A pressure sensor having a multilayer structure includes: a piezoelectric fiber layer in which a first braided yarn having a plurality of dielectric fiber yarns and a conductive yarn and a second braided yarn having a plurality of dielectric fiber yarns and a conductive yarn are knitted; and an upper fiber layer and a lower fiber layer disposed above and below the piezoelectric fiber layer. When the piezoelectric fiber layer is pressed in a thickness direction, a plurality of electrical signals generated in a matrix form are output to a sensing circuit. The body pressure sensor can be easily configured, manufactured according to its use.

Description

Multi-layered body pressure sensor {BODY PRESSURE SENSOR HAVING A MULTI-LAYER STRUCTURE}

The present invention relates to a body pressure sensor, and more particularly, to a body pressure sensor having a multi-layered structure in the form of a thin fabric that can be applied to a blanket or a mattress cover.

The body pressure sensor is a device that measures pressure applied to a person's body for each body part. The body pressure sensor can be used in sports clothing to recognize the movements of the human body and can be used for posture correction or training, and can be used in bedsore prevention mattresses to measure body pressure and to distribute body pressure optimally.

For example, the body pressure sensor may be used to measure the body pressure formed by the body of a person lying in an immovable posture for a long time on the bedside under pressure. Blood circulation disorders occur due to changes in body pressure of a person lying on the bed in an immovable position for a long time using such a body pressure sensor, and tissue damage due to ischemia in the skin, subcutaneous fat, and muscles due to insufficient supply of coral and nutrients (pressure ulcer, pressure ulcer, bed sore) can be predicted.

An example of the above-described body pressure sensor is disclosed in Korean Patent Publication No. 10-1080063,'A body pressure measuring device for preventing bedsores and a user terminal device connected thereto'. This prior art body pressure measuring device includes a plurality of force sensing resistor (FSR) sensors arranged in a natrix shape, and analog digital (A/D) that converts the output value of the sensor into a digital value. And a converter and a transmission unit for transmitting the digital value to the user terminal device.

FSR is a type of pressure sensor as a sensor that converts physical force and weight into resistance values. In general, the FSR has a thin film form in which a circuit-printed layer (FPC) and a conductive material-coated film layer (eg, MD film) are stacked with a spacer forming a spatial gap therebetween. The FSR in the form of a thin film is configured to output a resistance value that changes according to the force applied in the stacking direction through the A/D converter.

On the other hand, sensors that read changes due to external force as electrical signals have evolved to be lighter and smaller, and recently, new sensors such as fabric-type sensors that can be used in various fields are being developed because they are easy to bend and fold through fibers. In addition, there is an increasing demand for such a fabric-type sensor.

Korean Registered Patent Publication No. 10-1080063 (2011.11.09)

An object of the present invention is to provide a body pressure sensor having a new structure in response to the demand for a new fabric-type sensor.

Another object of the present invention is to provide a multi-layered body pressure sensor that can be conveniently constructed, manufactured, and used according to a purpose.

A multilayer body pressure sensor according to an aspect of the present invention for solving the above technical problem is a piezoelectric knitting a first braid yarn having a plurality of dielectric fiber yarns and a conductive yarn, and a second braid yarn having a plurality of dielectric fiber yarns and a conductive yarn Fibrous layer; And an upper fibrous layer and a lower fibrous layer disposed above and below the piezoelectric fibrous layer, wherein when the piezoelectric fibrous layer is pressed in the thickness direction, a plurality of electrical signals generated in a matrix form are output to the sensing circuit.

In one embodiment, the multilayer body pressure sensor further includes another piezoelectric fiber layer directly laminated on the piezoelectric fiber layer between the upper fiber layer and the lower fiber layer, and the other piezoelectric fiber layer has a plurality of dielectric fiber yarns and a conductive yarn. It has a structure in which a third ply yarn and a fourth ply yarn having a plurality of dielectric fibers and a conductive yarn are knitted.

In one embodiment, each of the piezoelectric fiber layer and the other piezoelectric fiber layer has a surface resistance of 10 ² to 10 ³ Ω/sq.

In one embodiment, the number of different piezoelectric fiber layers is determined differently according to the use of the body pressure sensor.

In one embodiment, when the number of the other piezoelectric fiber layers is two, the resistance of the fabric including the piezoelectric fiber layer and the other piezoelectric fiber layer is at least twice the surface resistance of the fabric including only the piezoelectric fiber layer in the same pressure atmosphere, 3 Less than twice as long.

In one embodiment, when the number of the other piezoelectric fiber layers is 4, the repeated contraction time of the fabric including the piezoelectric fiber layer and the other piezoelectric fiber layer is twice the repeated contraction time of the fabric including only the piezoelectric fiber layer in the same pressure atmosphere. To 3 times.

In one embodiment, the upper and lower fiber layers include an upper electronic fiber layer and a lower electronic fiber layer in which a conductive yarn and a fiber yarn are knitted, and the conductive yarn of the upper electronic fiber layer and the conductive yarn of the lower electronic fiber layer publish the piezoelectric fiber layer. They are arranged to extend in a direction intersecting each other in a matrix form.

When the above-described multi-layered body pressure sensor is used, it is possible to provide a fibrous body pressure sensor including a different number of piezoelectric fibrous layers depending on the application. In addition, it is possible to provide an inexpensive device structure with excellent reliability of body pressure sensing, which is easy to manufacture in a fibrous body pressure sensor.

In addition, according to the present invention, by changing the number of piezoelectric fiber layers according to the use, it is possible to simply manufacture a body pressure sensor according to the use of a bed cover, a floor mat, a wheelchair cushion, etc. through substantially the same manufacturing apparatus, thereby reducing the manufacturing cost. It can be lowered, and there is an advantage of maintaining and increasing the stability and reliability of the device by a simple structure.

1 is a photograph of implementing a multi-layered body pressure sensor according to an embodiment of the present invention.
Figure 2 is a schematic cross-sectional view for explaining the structure of the body pressure sensor of Figure 1;
3 is a diagram illustrating a piezoelectric fiber layer of the body pressure sensor of FIG. 2.
4 is a diagram illustrating an electronic fiber layer of the body pressure sensor of FIG. 2.
Figure 5 is a cross-sectional view for explaining the operating principle of the body pressure sensor of Figure 2;
6 is a schematic cross-sectional view for explaining another structure of the body pressure sensor of FIG. 1.
7 is a schematic cross-sectional view for explaining another structure of the body pressure sensor of FIG. 1.
8 is a graph of measuring resistance according to pressure in the body pressure sensor of FIGS. 2, 6 and 7;
9 is a diagram illustrating body pressure measurement using the body pressure sensor of FIG. 1.
10 is a diagram illustrating another example of body pressure measurement using the body pressure sensor of FIG. 1.

Since the present invention can make various changes and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to a specific embodiment, it should be understood to include all changes, equivalents, or substitutes included in the spirit and scope of the present invention. In describing each drawing, similar reference numerals have been used for similar elements.

The terms used in the present specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms related to "comprises", "have", etc. are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof does not preclude in advance.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a photograph of implementing a multi-layered body pressure sensor according to an embodiment of the present invention, and FIG. 2 is a schematic cross-sectional view illustrating the structure of the body pressure sensor of FIG. 1. FIG. 3 is a diagram illustrating a piezoelectric fiber layer of the body pressure sensor of FIG. 2, and FIG. 4 is a diagram illustrating an electronic fiber layer of the body pressure sensor of FIG. 2. And FIG. 5 is a cross-sectional view for explaining the principle of operation of the body pressure sensor of FIG. 2.

1 and 2, the multilayer body pressure sensor 100 according to the present embodiment is a piezoelectric fiber layer 20 in which a first ply yarn 21 and a second ply yarn 22 are knitted as a fibrous sensor or electronic fiber. It includes a lower fibrous layer 10 and an upper fibrous layer 30 disposed below and above the piezoelectric fibrous layer 20, respectively.

The lower fibrous layer 10 may be woven or braided using a dielectric fiber yarn as the weft yarn 11 or warp yarn, and a conductive yarn or metal yarn as the warp yarn 12 or weft yarn. In addition, the upper fiber layer 30 may be woven or braided using another dielectric fiber yarn as the weft 31 or warp yarn, and the conductive yarn or metal yarn as the warp 32 or weft yarn.

As shown in FIG. 3, the first ply yarn 21 of the piezoelectric fiber layer 20 uses a fiber yarn 21a and a metal yarn or a conductive yarn 21b, and has a structure or shape that is not substantially twisted. Similarly, the second ply yarn 22 uses other fiber yarns 22a and metal yarns or conductive yarns 22b, and has a structure or shape that is not substantially twisted. The piezoelectric fiber layer 20 has a surface resistance of 10 ² to 10 ³ Ω/sq.

The lower fibrous layer 10 and the upper fibrous layer 30 have a structure in which fiber yarns 11 and 31 and metal yarns 12 and 32 are used as weft yarns and warp yarns, respectively.

As described above, the upper fibrous layer 30 and the lower fibrous layer 10 may be referred to as an upper electronic fiber layer and a lower electronic fiber layer in which conductive yarns are knitted. The conductive yarns of the upper electronic fiber layer and the conductive yarns of the lower electronic fiber layer are disposed to extend in a direction intersecting each other in a matrix form and through the piezoelectric fiber layer 20.

According to the above configuration, as shown in FIG. 5, when the piezoelectric fiber layer 20 is pressed in the thickness direction by a predetermined external pressure, a plurality of electrical signals generated in a matrix form are transmitted to the lower fiber layer 10 and the upper side. It may be output to the sensing circuit 200 through the fiber layer 30.

The above-described body pressure sensor may additionally have another piezoelectric fiber layer. In that case, the number of different piezoelectric fiber layers is determined differently depending on the use of the body pressure sensor.

6 is a schematic cross-sectional view for explaining another structure of the body pressure sensor of FIG. 1.

Referring to FIG. 6, the multilayer body pressure sensor 100 according to the present embodiment includes two different piezoelectric fiber layers 20b directly stacked on the basic piezoelectric fiber layer 20a between the upper fiber layer 30 and the lower fiber layer 10. ,20c).

Here, the other piezoelectric fiber layer may have a structure in which a third ply yarn having a plurality of dielectric fiber yarns and a conductive yarn, and a fourth ply yarn having a plurality of dielectric fiber yarns and a conductive yarn are knitted.

When the number of other piezoelectric fiber layers is 2, that is, when the number of piezoelectric fiber layers is 3, the resistance of the fabric including the piezoelectric fiber layer and the other piezoelectric fiber layer is at least twice the surface resistance of the fabric including only the piezoelectric fiber layer in the same pressure atmosphere, It is less than 3 times.

7 is a schematic cross-sectional view for explaining another structure of the body pressure sensor of FIG. 1.

Referring to FIG. 7, the multilayer body pressure sensor 100 according to the present embodiment includes four different piezoelectric fibrous layers 20b directly stacked on the basic piezoelectric fibrous layer 20a between the upper fibrous layer 30 and the lower fibrous layer 10. ,20c,20d,20e).

In this way, when the number of stacked piezoelectric fiber layers is controlled, different body pressures can be reliably measured according to the use of the body pressure sensor using piezoelectric fiber layers that exhibit different surface resistances depending on the number of stacks.

8 are graphs measuring resistance according to pressure in the body pressure sensor of FIGS. 2, 6 and 7;

8, when a pressure of 350 kPa is applied to the body pressure sensor according to the present embodiment twice every 50 seconds (see (a)), the resistance value measured by the first body pressure sensor having one piezoelectric fiber layer ( resistance) (see (b)), a resistance value measured by a second body pressure sensor having three piezoelectric fiber layers (see (b)), and a resistance value measured by a third body pressure sensor having five piezoelectric fiber layers ((b) )) shows different meaningful results.

The first body pressure sensor shows a resistance value in the range around 4,000 Ω, the second body pressure sensor shows a resistance value in the range around 10,000 Ω, and the third body pressure sensor shows a resistance value in the range around 4000 Ω and its repetitive contraction time is single piezoelectricity. It can be seen that it is 2 to 3 times longer compared to the repetitive contraction time compared to the case including only the fiber layer.

FIG. 9 is a diagram illustrating body pressure measurement using the body pressure sensor of FIG. 1, and FIG. 10 is a diagram illustrating another example of body pressure measurement using the body pressure sensor of FIG. 1.

As shown in (a) and (b) of FIG. 9, when the user is lying on the cotton fabric equipped with the body pressure sensor according to the present embodiment, from high body pressure to low body pressure in the order of hips, shoulders, feet and heels. It can be seen that the distribution of is well represented.

In addition, as shown in (a) and (b) of Fig. 10, when the user is sitting on the cotton fabric equipped with the body pressure sensor according to the present embodiment, the body pressure is lower in the order of hip, heel, calf, and thigh. It can be seen that the distribution up to the body pressure is well represented.

As described above, when the multilayer body pressure sensor according to the present embodiment is used, the number of piezoelectric fiber layers is determined differently depending on the use of a wheelchair, bed, matrix, blanket, carpet, etc., so that body pressure can be effectively measured according to the purpose.

Although the above has been described with reference to preferred embodiments of the present invention, those skilled in the art can variously modify and change the present invention without departing from the spirit and scope of the present invention described in the following claims. You will understand that there is.

Claims (7)

A piezoelectric fibrous layer in which a first braided yarn having a plurality of dielectric fiber yarns and a conductive yarn, and a second braided yarn having a plurality of dielectric fiber yarns and a conductive yarn is knitted; And
An upper fibrous layer and a lower fibrous layer disposed above and below the piezoelectric fibrous layer;
Including,
A multi-layered body pressure sensor for outputting a plurality of electrical signals generated in a matrix form to a sensing circuit when the piezoelectric fiber layer is pressed in a thickness direction. The method according to claim 1,
Further comprising another piezoelectric fibrous layer directly laminated on the piezoelectric fibrous layer between the upper fibrous layer and the lower fibrous layer,
The other piezoelectric fiber layer is a multi-layered body pressure sensor having a structure in which a third ply yarn having a plurality of dielectric fibers and a conductive yarn, and a fourth ply yarn having a plurality of dielectric fiber yarns and a conductive yarn are knitted. The method according to claim 2,
Each of the piezoelectric fiber layer and the other piezoelectric fiber layer has a surface resistance of 10 ² to 10 ³ Ω/sq. The method according to claim 2 or 3,
The number of the other piezoelectric fiber layers is determined according to the use of the body pressure sensor multi-layered body pressure sensor. The method of claim 4,
When the number of the other piezoelectric fiber layers is two, the resistance of the fabric including the piezoelectric fiber layer and the other piezoelectric fiber layer is at least 2 times or less than 3 times the surface resistance of the fabric including only the piezoelectric fiber layer in the same pressure atmosphere. sensor. The method of claim 4,
When the number of the other piezoelectric fiber layers is 4, the repeated contraction time of the fabric including the piezoelectric fiber layer and the other piezoelectric fiber layer is 2 to 3 times the repeated contraction time of the fabric including only the piezoelectric fiber layer in the same pressure atmosphere. Body pressure sensor. The method according to claim 1,
The upper fibrous layer and the lower fibrous layer include an upper electronic fiber layer and a lower electronic fiber layer in which conductive yarn and fiber yarn are knitted,
The conductive yarn of the upper electronic fiber layer and the conductive yarn of the lower electronic fiber layer are disposed to extend in a direction intersecting each other in a matrix form and spread the piezoelectric fiber layer.

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