JP2011045613A - Diaper wetting detector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diaper wetting detector capable of detecting wetting of a diaper easily and efficiently as well as gently to a wearer's skin and safely to a human body. <P>SOLUTION: The diaper wetting detector includes a sensor part 13 made of woven fabric with at least two conductive strings X, X arranged in a longitudinal direction; a resonance circuit part 14 including a coil and a capacitor, and allowing the two conductive strings to be connected to the resonance circuit; and a detecting part 15 including an oscillator of resonance frequency of the resonance circuit part, a receiver and a driving power source to detect the presence of excrement stuck to the sensor part from a resonant condition in the resonance circuit part. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a diaper wetting sensor using a conductive yarn, and more particularly to a diaper wetting detection device that can easily detect diaper wetting without contact.

  In recent years, the number of people who need nursing care tends to increase, and the number of diaper wearers also tends to increase. A diaper wearer is uncomfortable when the diaper becomes wet with excrement (urine or stool) due to incontinence, etc., so caregivers need to detect this as soon as possible, so various diaper wetness sensors have been developed. (See Patent Documents 1-6).

  A diaper wetness sensor constituted by a metal leaf spring or a metal plate and a member whose volume is contracted by absorbing water uses a switch that operates when the leaf spring and the metal plate come into contact with each other during absorption. However, there is a problem that the switch becomes complicated and expensive because of a switch having a complicated structure. In addition, the use of a hard material such as a metal material has a problem that use on a diaper to be worn can cause discomfort and injury.

  In addition, a diaper wetting sensor consisting of a PVA fiber impregnated with copper ions and a thread imparted with conductivity using copper sulfide fine particles is based on the change in conductivity of the sensor when the diaper is wet. It is. A sensor using a conductive yarn impregnated with copper sulfide or copper ions is flexible and has the same feeling as clothing, but there is a problem that copper ions and the like are adversely affected on the human body.

  Moreover, a diaper wetness sensor has been proposed in which a metal layer is formed on a paper diaper by lamination or vapor deposition, and used as an electrode. In the case of a sensor using a metal foil, flexibility is ensured, but stuffiness associated with a decrease in air permeability tends to occur, which may cause discomfort. In addition, there is a concern that the wire may be disconnected due to bending due to movement or the like after mounting, and there is a problem that a reliable operation may not be obtained.

Japanese Patent No. 3376769 Japanese Patent No. 3717068 Japanese Patent Laid-Open No. 11-347058 JP 2000-139983 A JP 2007-240470 A Utility Model Registration No. 3147110

  The present invention has been made based on the above circumstances, and provides a diaper wetting detection device that is gentle to the wearer's skin, safe to the human body, and capable of detecting diaper wetting without contact and efficiently. For the purpose.

  The diaper wetting detection device of the present invention comprises a sensor unit made of a woven fabric in which at least two conductive yarns are arranged in the longitudinal direction, a coil and a capacitor, and the two conductive yarns are arranged in a resonance circuit thereof. A resonance circuit unit that can be connected, an oscillator having a resonance frequency of the resonance circuit unit, a receiver, and a drive power supply are provided, and the presence or absence of excrement adhered to the sensor unit is detected from the resonance state in the resonance circuit unit. And a detection unit that performs the above-described operation.

  By connecting the two conductive yarns of the sensor unit to both ends of either the coil L or the capacitor C of the resonant circuit unit, if the woven fabric between the two conductive yarns is in a dry state, The resonance frequency is not affected, and resonates with respect to the electromagnetic wave having the resonance frequency from the detection unit. When the woven fabric between the two conductive yarns is wetted by an electrolyte solution such as urine, the impedance between the two conductive yarns is remarkably reduced, and a state close to a conductive state is obtained. As a result, a low impedance (particularly, the reactance component is remarkably reduced) is connected in parallel to the coil L or the capacitor C of the resonance circuit section, and the resonance circuit does not resonate with the electromagnetic wave having the resonance frequency. Diaper wetting can be detected easily and efficiently by contact.

  The sensor part is made of an anisotropic conductive woven fabric in which at least two conductive yarns are arranged in the longitudinal direction. Therefore, the sensor part is gentle to the wearer's skin, and the resonance circuit part attached to the diaper body is checked for resonance. Since non-contact detection is possible, diaper wetting can be detected safely, easily and efficiently to the human body.

It is a perspective view of the diaper wetness detection apparatus of Example 1 of this invention. It is a top view of the state which connected the two conductive thread | yarns of the sensor part to the resonance circuit part. It is a perspective view which shows typically the weaving state of the warp and the weft of an anisotropic conductive fabric. (A) shows two conductive yarn terminals at the end of the sensor section, (b) is a plan view showing terminals for connection of the resonant circuit section, and (c) shows two terminals at the end of the sensor section. It is sectional drawing which shows the state which connected the terminal of this conductive thread | yarn to the terminal for connection of a resonance circuit part. (A) is an equivalent circuit diagram in a state where the woven fabric is dry and does not affect the resonance circuit, and (b) is an equivalent circuit diagram in a state where the woven fabric is wet and a low impedance is connected in parallel to the resonance circuit. is there. It is a graph which shows the measurement result of the absolute value of the impedance between conductive yarn in the dry state in 1 MHz at the time of changing the distance between two conductive yarns, and a wet state. It is a graph which shows the measurement result of the absolute value of the impedance between conductive yarns in the dry state and the wet state at 10 MHz when the distance between two conductive yarns is changed. It is sectional drawing which shows the various example of arrangement | positioning of the sensor part in a diaper main body. It is sectional drawing of the sensor part of Example 2 of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 9. In addition, in each figure, the same code | symbol is attached | subjected and demonstrated to the same or equivalent member or element.

  FIG. 1 shows an outline of a diaper wetting detection apparatus according to the present invention. The diaper main body 11 made of a paper diaper or the like is provided with an absorbent material 12 and absorbs excrement (urine or stool) when the wearer incontinence or the like. And in the diaper wetting detection apparatus of this invention, the sensor part 13 which consists of an anisotropic conductive woven fabric which has arrange | positioned at least 2 electroconductive thread | yarn in the longitudinal direction inside the diaper main body 11 is provided.

  A configuration example of the anisotropic conductive woven fabric is shown in FIG. The anisotropic conductive woven fabric includes at least two conductive yarns X and X between the insulating yarns as the warp yarn x, and the insulating yarn is woven as the weft yarn y. In this example, electroless copper-plated yarn made of polyester fiber is used as the conductive yarn, and yarn made of polyester fiber is used as the insulating yarn. The woven conductive yarn is arranged in parallel to the longitudinal direction of the woven fabric, and is electrically conductive in this direction, and at the same time has the same flexibility as a normal yarn, and becomes a woven fabric that is gentle to the wearer's skin. It has the characteristics. Moreover, it has higher retainability with respect to excrement by using a polyester fiber with high water absorption for the insulating yarn.

  FIG. 2 shows a state in which the sensor unit and the resonance circuit unit are connected, and two conductive yarns of the sensor unit 13 made of anisotropic conductive woven fabric are connected to the resonance circuit unit 14 made of the coil L and the capacitor C. Has been. In this example, one end of the two conductive yarns of the sensor unit 13 is connected to either end of either the coil L or the capacitor C of the resonance circuit unit 14 and the other end is opened.

  As shown in FIG. 4, it is preferable that terminals of the two conductive yarns are provided with terminals 20 a and 20 b so that they can be connected to the terminals 21 a and 21 b of the resonance circuit unit 14. At this time, it is preferable to provide a lid L that can be opened and closed so that the sensor unit 13 and the resonance circuit unit 14 can be arbitrarily connected. Thereby, it is also possible to make only the sensor part 13 disposable and to use the resonance circuit part 14 repeatedly.

  The detection unit 15 includes an oscillator having a resonance frequency of the resonance circuit unit 14, a receiver, and a drive power supply, and detects the presence or absence of excrement adhered to the sensor unit 13 from the resonance state in the resonance circuit unit 14. That is, when excrement adheres to the sensor unit 13, the impedance between the two conductive yarns changes dramatically, and the resonance frequency of the resonance circuit unit 14 changes. Then, since the reception power of the receiver changes, this can be detected and displayed on the display unit of the detection unit 15, or a warning sound can be output to notify a caregiver or the like of detection of diaper wetting.

  The detection unit 15 is housed in, for example, a box-shaped case, and when the diaper wearer is sleeping, for example, the detection unit 15 is placed in a position separated from the diaper main body 11 so that the diaper can be easily wet without contact. It can be detected.

  If the space between the two conductive yarns is dry, the resonance circuit of the resonance circuit unit 14 is not affected, and the equivalent circuit of FIG. To do. When the space between two conductive yarns is wetted by an electrolyte such as urine, the equivalent circuit is as shown in FIG. 5B, and the impedance between the conductive yarns is reduced. Accordingly, the capacitor Cw and the resistor Rw are added in parallel to the coil L or the capacitor C in the resonance circuit, so that different resonance states are generated, and the resonance circuit does not resonate with the electromagnetic wave having the resonance frequency, so that the diaper is wet. It can be detected efficiently.

  For example, when a high frequency of 1 MHz and 10 MHz is applied between the two conductive yarns of the sensor unit 13, the anisotropic conductive woven fabric to be the sensor unit is immersed in a 0.8% sodium chloride aqueous solution modeled on urine. Thus, it has been confirmed that the equivalent impedance between the two conductive yarns is reduced to about 1/100 at 1 MHz and to 1/10 at 10 MHz compared to before immersion.

  The change in the impedance component before and after immersing the anisotropic conductive woven fabric in the electrolytic solution was a high frequency measurement, or the resistance component was detected even in a dry state. Although the resistance component did not change significantly before and after the immersion of the electrolyte, it was found that the capacitive reactance component was greatly reduced. This indicates that the capacitance of the anisotropic conductive woven fabric between the two conductive yarns increases due to the attachment of excrement. Due to the significant decrease in the capacitive reactance component, the detection sensitivity can be improved with respect to the method of detecting the decrease in the resistance component.

  FIG. 6 shows an impedance measurement result between two conductive yarns at 1 MHz, and FIG. 7 shows an impedance measurement result between two conductive yarns at 10 MHz. In both cases, the horizontal axis indicates the distance between the two conductive yarns, and the vertical axis indicates the absolute value of the impedance in the dry state, and the right side indicates the absolute value of the impedance in the wet state. From these data, it can be seen that a stable detection result can be obtained when the interval between the two conductive yarns is 2 mm or more, and it is preferable that the interval between the two conductive yarns is 2 mm or more.

  As shown in FIG. 8, the sensor unit 13 can detect that the sensor unit 13 has been wetted by urine or the like by being disposed in the vicinity of the absorbent material 12 inside the disposable diaper. For example, as shown to Fig.8 (a), when arrange | positioning in the location near the wearer of the upper part of the absorber 12, it becomes possible to detect immediately after incontinence. Moreover, as shown in FIG.8 (b), when arrange | positioning in the lower part of the absorber 12 and the outer side of the diaper main body 11, it does not react by a trace amount incontinence, but the sensor part 13 can react by a fixed amount of incontinence. . Moreover, as shown in FIG.8 (c), when arrange | positioning inside the absorber 12, it does not react by a trace amount incontinence, but the detection of the diaper wetting stable after time progress is attained.

  The above Example 1 demonstrated the example which forms the sensor part 13 with 1 sheet | seat cloth, and arrange | positions in the vicinity of the absorber 12 inside a diaper main body. However, by forming the sensor unit 13 as shown in FIG. 9, it is possible to use an existing paper diaper as it is. In this case, the surface of the sensor unit 13 is coated with a material 17 (polyolefin nonwoven fabric or the like) 17 having high moisture permeability and low water retention, so that irritation to the contacting skin can be reduced. Moreover, the back surface of the sensor unit 13 is a single-sided adhesive tape or double-sided tape 18 and can be fixed to a paper diaper.

  As described above, in the diaper wetness detection method using the resonance circuit, the resonance circuit itself does not require a power source, and the risk of electric shock of the wearer due to a failure or the like can be avoided. Moreover, by integrally forming the resonance circuit unit 14 in the diaper main body 11 together with the sensor unit 13, it can be used in a disposable manner as in the conventional paper diaper. Moreover, the resonant circuit unit 14 is provided with a detachable connection terminal and is detachably attached to the diaper main body 11 so that it can be easily separated and reused at the time of disposal. As a result, the amount of waste can be reduced, and the unit price of one disposable diaper can be reduced. In this case, the resonant circuit section 14 is covered with a flat match box-shaped resonant circuit section or a flexible film-shaped resonant circuit section laminated with the resonant circuit section 14 and is attached by being sandwiched like a clip. It is preferable that a simple connection can be made.

  In addition, although the diaper main body demonstrated in the example of the paper diaper, it is applicable also to articles | goods which absorb excrement, such as a cloth diaper or a pad.

  In the above embodiment, an example in which two conductive yarns are connected in parallel to either the coil L or the capacitor C of the resonance circuit unit 14 has been described. However, two conductive threads are connected in series to the coil L and the capacitor C. A sex yarn may be connected. Thereby, when the sensor unit 13 is in a dry state, the resonance circuit is open and does not resonate, but when the sensor unit 13 is in a wet state, the two conductive yarns are in a conductive state and are in a resonant state at a predetermined frequency.

  Although one embodiment of the present invention has been described so far, it is needless to say that the present invention is not limited to the above-described embodiment, and may be implemented in various forms within the scope of the technical idea.

  The present invention is such that a sensor unit made of anisotropic conductive woven fabric is attached to a diaper main body such as a nursing diaper, and is gentle to the skin, and the presence or absence of resonance of a resonance circuit unit attached to the diaper main body is not Because it can be detected by contact, diaper wetting can be detected safely and easily on the human body. Therefore, it can be suitably used for detecting diaper wetting in the field of nursing care and the like.

Claims (9)

A sensor unit comprising a woven fabric in which at least two conductive yarns are arranged in the longitudinal direction;
A resonance circuit unit comprising a coil and a capacitor, and capable of connecting the two conductive yarns to the resonance circuit;
A diaper comprising: an oscillator having a resonance frequency of the resonance circuit unit; a receiver; and a driving power source; and a detection unit that detects the presence or absence of excrement adhered to the sensor unit from a resonance state in the resonance circuit unit. Wet detection device.   2. The diaper wetting detection device according to claim 1, wherein the woven fabric includes two conductive yarns arranged in parallel in a longitudinal direction, and a terminal connected to the resonance circuit unit at an end thereof.   The diaper wetting detection device according to claim 1, wherein the conductive yarn is a yarn obtained by electroless plating a yarn made of polyester fiber.   The diaper wetting detection device according to claim 1, wherein the insulating yarn of the woven fabric is a yarn made of polyester fiber.   The diaper wetting detection device according to claim 1, wherein the resonance circuit unit is formed by arranging a pattern made of a conductive material on a plastic film to form the coil and the capacitor.   The diaper wetting detection device according to claim 1, wherein a distance between two conductive yarns in the sensor unit is 2 mm or more.   The diaper wetting detection device according to claim 1, wherein the sensor unit is disposed in the vicinity of an absorbent material inside the diaper main body.   The diaper wetting detection device according to claim 1, wherein the sensor unit includes an adhesive single-sided tape or a double-sided tape on a back surface, and can be fixed to a diaper main body.   The diaper wetting detection device according to claim 1, wherein the sensor unit is coated on a surface with a material having high moisture permeability and low water retention.

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