JP5587817B2 - Blood detector for artificial dialysis - Google Patents

Description

  The present invention relates to an apparatus for detecting blood leakage that occurs during an artificial dialysis treatment. In addition, this apparatus is used also as an apparatus which detects the leakage of the infusion which generate | occur | produced during the infusion.

  Devices for detecting moisture have been conventionally provided. For example, Cited Document 1 is applied to an adult diaper, and notifies the diaper replacement time by detecting moisture (urine). The moisture detection device includes a sensor sheet including a pair of electrodes, and a predetermined low voltage is applied between the electrodes. When a certain amount or more of moisture (urine) adheres to the sensor sheet, the current flowing between the electrodes fluctuates, so that the diaper replacement time is notified. In this sensor sheet, a special conductive material is disposed between the electrodes. This conductive material extremely reduces the conductivity between the electrodes in a dry state, but increases the conductivity between the electrodes when water is absorbed. Thereby, the sensor sheet | seat is comprised as a water | moisture-content detection switch electrically connected by presence of a water | moisture content. When the moisture detection switch is turned on, the presence of moisture, that is, the time for replacing the adult diaper is notified by a buzzer or other notification means.

  The sensor sheet is also used in hemodialysis treatment in a medical field. In hemodialysis treatment, a dialysis monitoring device that detects an abnormal concentration of dialysis fluid is used, and the dialysis fluid concentration during treatment is monitored. In addition, bleeding accidents caused by the withdrawal of needles during treatment have occurred in the past, but the presence or absence of bleeding caused by the withdrawal of the needles was left to the visual check of medical personnel. The causes of bleeding accidents due to needle extraction are various, such as patient consciousness disturbance, itching, shoulder movements due to shoulder and back pain, etc., and coma during treatment. It is necessary repeatedly. Although bleeding accidents during artificial dialysis must be reliably prevented, there are limits to the methods that rely on human attention in the first place. For this reason, a moisture detection device has been proposed that can more accurately detect blood leakage during artificial dialysis (see, for example, Patent Document 2).

  FIG. 19 is a schematic diagram of a conventional moisture detection device used for artificial dialysis treatment. FIG. 20 is a partially enlarged cross-sectional view of the moisture sensor provided in the moisture detection device.

  The moisture sensor 2 employed in the moisture detection device 1 includes a water absorbing material 5. This water absorbing material 5 has an overlay 3 and an underlay 4 that show electrical insulation in a dry state. The upper cover 3 and the lower cover 4 have water absorption. An electrode 7 including an electric resistance element 6 is sandwiched between the underlay 4 and the overlay 3. Further, a conductive adhesive 8 is interposed between the underlay 4 and the overlay 3 to increase the conductivity when absorbing water. In the moisture sensor 2, the resistance value of the electric resistance element 6 is set to about 20 kΩ, for example. Since the conductive adhesive 8 is used, when there is a relatively large amount of water (that is, bleeding due to needle removal during dialysis treatment), the electrode 7 is electrically connected to the water. The conductivity between the electrodes 7 is increased. Specifically, the resistance value is set to decrease to several kΩ.

  As described above, the conventional moisture sensor 2 does not detect a small amount of moisture (for example, sweat generated during treatment), and reliably detects bleeding due to the withdrawal of the needle, and the notification device S notifies that fact. In addition, even when no moisture is present as described above, the electrodes 7 are not completely insulated from each other, so that the presence or absence of a contact failure or other defects of the moisture detecting device 1 is confirmed.

  When the moisture sensor 2 detects bleeding, the necessary treatment is applied and the moisture sensor 2 must be replaced. A connector C is conventionally provided between the notification device 8 and the moisture sensor 2 so that the moisture sensor 2 can be replaced quickly. Various proposals have been made in order to easily and reliably attach and detach the connector C to and from the moisture sensor 2 (see, for example, Patent Document 3).

JP 2002-55074 A JP 2004-177120 A JP 2007-132703 A

  However, the human constitution is very diverse, and the salt concentration in sweat is not constant, and is about 0.3% to 1.7% by mass depending on the person. Furthermore, it varies from those with low sweating to those with abnormally high sweating. For example, when the moisture sensor 2 is wound around an arm and used for a long time, a large amount of sweat may accumulate in the underlay 4. In such a case, there is a problem that the electrode 7 is electrically connected by the sweat and the moisture detecting device 1 malfunctions.

  Artificial dialysis treatment is a procedure that requires several hours. Therefore, a needle pulling accident may occur when the patient moves the arm consciously or unconsciously during the treatment. Such a needle pull-out accident frequently occurs especially in patients with dementia symptoms. If such a needle pull-out accident occurs, it takes time to replace the moisture sensor 2, and artificial dialysis is performed. The treatment will still take a long time.

  In addition, since the moisture sensor 2 is used for the artificial dialysis treatment, it is necessary to be surely sterilized in a new state. Therefore, conventionally, in the manufacturing process of the moisture sensor, the sterilization gas is sealed in the sterilization bag after the moisture sensor 2 is accommodated in the sterilization bag. However, in this sterilization process, after the sterilization gas is supplied to the sterilization bag, the sterilization bag must be sealed, and it is difficult to realize complete sterilization. Therefore, the sterilization gas sealing operation needs to be performed in a sterilized space, and as a result, there is a problem that the manufacturing cost of the moisture sensor increases.

  Therefore, an object of the present invention is for artificial dialysis, which can prevent a malfunction due to sweat during an artificial dialysis treatment, and can reliably detect bleeding due to the withdrawal of the needle, and can also detect the probability of a needle withdrawal accident. It is to provide a blood detection device.

  (1) Since the above-described object is achieved, the blood detection device for artificial dialysis according to the present invention provides moisture that detects the presence of blood by exhibiting insulation in a dry state and conductivity in a state containing moisture. A sensor, a notification device that notifies that at least the moisture sensor detects the presence of blood, and a connector that connects the notification device and the moisture sensor. The moisture sensor includes an air-permeable base sheet and an electrode sheet having a pair of electrodes arranged on the base sheet, and a water-repellent filter sheet that is superimposed on the electrode sheet and has a large number of small holes. And a water-permeable sheet having a certain water retention property superimposed on the filter sheet. The connector is provided in the casing, the conductive electrode connecting member provided in the casing, and disposed so as to be bridged between the pair of electrodes by sandwiching one end of the moisture sensor. And a clip capable of holding the other end of the moisture sensor and holding the moisture sensor with a certain holding force. The conductive electrode connecting member includes a piercing blade that pierces the electrode sheet, and the clip includes a normally closed switch that is turned off when the moisture sensor is sandwiched.

  The moisture sensor is laid under the patient's arm in the artificial dialysis treatment, and the patient's arm is disposed on the water-permeable sheet. If bleeding occurs from the patient's arm due to withdrawal during treatment, the blood is once retained by the water-permeable sheet, but if there is a certain amount of bleeding, the blood wets the electrode sheet. The pair of electrodes are electrically connected. The conduction between the electrodes is used as a predetermined input signal, and the input signal is transmitted to the alarm device via the connector. Thereby, the said alarm | alarm device act | operates and a blood leak is alert | reported.

  When dialysis treatment is performed for a long time, the patient's arm may sweat and a large amount of sweat may occur depending on the patient's constitution. However, the patient's arm is disposed on the breathable sheet, the filter sheet has a large number of small holes, and the base sheet constituting the electrode sheet is breathable. And passes through the moisture sensor, the sweat does not accumulate on the electrode sheet.

  When the connector is attached to the moisture sensor, one end of the moisture sensor is sandwiched between the conductive electrode connecting members. Thereby, the piercing blade pierces the electrode sheet, and the conductive electrode connecting member is bridged between the pair of electrodes. Since the piercing blade pierces the electrode sheet, the connector is easily and securely fixed to the moisture sensor. Further, since the piercing blade only pierces the electrode sheet (that is, only sandwiches the moisture sensor), the piercing blade can be easily extracted from the moisture sensor. Therefore, the work of attaching / detaching the connector to / from the moisture sensor is simple.

  When artificial dialysis is performed, the moisture sensor is wound around the patient's arm, and the other end of the moisture sensor is held by the clip. Since the clip includes a normally closed switch, the switch is turned off in a state where the moisture sensor is held by the clip. Since the clip only holds the moisture sensor with a certain holding force, for example, if the patient pulls the moisture sensor, the moisture sensor is detached from the clip, and the normally closed switch Is turned on.

  (2) It is preferable that the base sheet includes a polyethylene film in which a large number of fine works that exhibit air permeability and waterproofness are formed by being mixed with calcium carbonate.

  Since the main body of the base sheet is made of polyethylene, the manufacturing cost of the moisture sensor does not increase significantly.

  (3) It is preferable that an adhesive layer for bonding the electrode sheet and the water-permeable sheet also serves as the filter sheet.

  Thereby, there is an advantage that the structure of the moisture sensor is simplified and the manufacturing cost is further reduced.

  (4) Preferably, the normally closed switch has a pair of electrode plates arranged along a direction in which the clip sandwiches the moisture sensor. One electrode plate is elastically biased so as to contact the other electrode plate. A contact release bar for separating the one electrode plate from the other electrode plate when pressed by the moisture sensor while the clip holds the moisture sensor is provided.

  In this configuration, when the clip does not sandwich the moisture sensor, one electrode plate is in contact with the other electrode plate. That is, the normally closed switch is turned on. When the moisture sensor is sandwiched between the clips, the moisture sensor presses the contact release bar. Accordingly, the contact release bar presses one electrode plate, and the one electrode plate is separated from the other electrode plate. That is, the normally closed switch is turned off. When the moisture sensor is removed from the clip from this state, the one electrode plate is elastically biased to the other electrode plate, so that both the electrode plates come into contact with each other and the normally closed switch is ON. It becomes.

  Moreover, it is preferable that the moisture sensor according to the present invention further includes a packaging bag body that wraps the electrode sheet, the filter sheet, and the water-permeable sheet. The packaging bag body preferably includes a main body sheet having air permeability and a water-permeable sheet having a certain water retention property laminated inside the main body sheet.

  In this case, the electrode sheet, the filter sheet, and the water-permeable sheet are wrapped in a packaging bag. Since the packaging bag body has air permeability, the electrode sheet, the filter sheet, and the water-permeable sheet can be sterilized while being wrapped in the packaging bag body. This is because when the sterilizing gas is supplied from the outside of the packaging bag body, the sterilizing gas enters the inside of the packaging bag body and exerts a sterilizing action on the electrode sheet, the filter sheet, and the water-permeable sheet. Because you can. That is, the electrode sheet, the filter sheet, and the water-permeable sheet can be sterilized in a state of being sealed and packaged in a packaging bag.

  Since the moisture sensor includes the packaging bag, when the moisture sensor is used, that is, when the packaging bag is opened when the artificial dialysis treatment is started, the packaging bag is used. The body can function as a napkin when the needle for artificial dialysis is stabbed into the patient's arm. That is, after the packaging bag is opened, the patient places its arm on the opened packaging bag. Blood may leak when the needle for artificial dialysis is stabbed into the patient's arm, but even in that case, the water-permeable sheet is laminated inside the packaging bag, The leaked blood is absorbed by the water-permeable sheet of the packaging bag. This prevents the electrode sheet and the like from getting wet by blood leaked when the needle for artificial dialysis is inserted into the patient's arm.

  Furthermore, it is preferable that the peripheral edge part of the said packaging bag body is adhere | attached so that the said electrode sheet, a filter sheet, and a water-permeable sheet may be wrapped inside.

  In this configuration, the packaging bag body can be wrapped in approximately half so that the electrode sheet, the filter sheet, and the water-permeable sheet can be wrapped. In addition, at this time, only the peripheral edge of the packaging bag is adhered, and therefore the packaging bag is easily developed by separating the peripheral edge. Therefore, the packaging bag can be easily and quickly opened when the artificial dialysis treatment is started.

  According to the present invention, even when sweat comes out of the patient's arm during artificial dialysis, the sweat passes through the moisture sensor in the state of water vapor, so that the moisture sensor malfunctions due to the sweat. Is reliably prevented. In addition, since one end of the moisture sensor is sandwiched between the conductive electrode connecting members and the other end is temporarily held by the clip, when a tensile force acts on the moisture sensor, the other end of the moisture sensor is clipped. Easily detached from. Therefore, for example, when a patient pulls the moisture sensor at a site where artificial dialysis is performed, the moisture sensor is detached from the clip, and this is detected by the normally closed switch. That is, a sign of a needle pulling accident is detected, and a needle pulling accident is prevented in advance.

  In the present invention, by providing the packaging bag, the moisture sensor can be sterilized easily, reliably and inexpensively. In addition, even if the blood leaks when the needle for artificial dialysis is stabbed into the patient's arm, the blood is absorbed by the packaging bag, so a new moisture sensor is used by the blood. The electrode sheet is prevented from getting wet.

FIG. 1 is a schematic diagram of a blood detection device 10 for artificial dialysis according to an embodiment of the present invention. FIG. 2 is a cross-sectional view of the moisture sensor 11. FIG. 3 is an exploded perspective view schematically showing the structure of the moisture sensor 11. FIG. 4 is a diagram schematically showing a cross-sectional structure of the reinforcing sheet 22. FIG. 5 is a wiring diagram of the blood detector 10 for artificial dialysis. FIG. 6 is a perspective view of the connector 14. FIG. 7 is a perspective view of the connector 14. FIG. 8 is a diagram illustrating a positional relationship between the electrode connecting member 40 disposed in the casing 33 and the leg portion 35 of the lever 34. FIG. 9 is an enlarged perspective view of the connector 14. FIG. 10 is an enlarged perspective view of a main part of the connector 14. FIG. 11 is an enlarged exploded perspective view of the connector 14. FIG. 12 is an enlarged perspective view of the clip 41. FIG. 13 is a perspective view showing a usage state of the blood detector 10 for artificial dialysis. FIG. 14 is an exploded perspective view of a moisture sensor according to a first modification of one embodiment of the present invention. FIG. 15 is a diagram schematically showing an apparatus for forming the adhesive layer 91 used in the moisture sensor according to the first modification. FIG. 16 is an exploded perspective view of a moisture sensor according to a second modification of the embodiment of the present invention. FIG. 17 is a schematic diagram showing a cross-sectional structure of the packaging bag body 101 according to the second modification. FIG. 18 is a diagram illustrating the usage points of the packaging bag body 101 in the order of (a) to (c). FIG. 19 is a conceptual diagram showing a conventional moisture detection device used for artificial dialysis treatment. FIG. 20 is a partially enlarged cross-sectional view of a moisture sensor which is a detection unit of a conventional moisture detection device.

  Hereinafter, the present invention will be described in detail based on preferred embodiments with appropriate reference to the drawings.

  FIG. 1 is a diagram schematically showing a blood detection apparatus for artificial dialysis according to an embodiment of the present invention.

  The blood detector 10 for artificial dialysis mainly monitors bleeding from a patient in an artificial dialysis treatment. This blood detection device 10 for artificial dialysis includes a moisture sensor 11. During the treatment, the patient's arm is placed on the moisture sensor 11, and in the unlikely event that blood leaks, the moisture sensor 11 detects this. The moisture sensor 11 is connected to the alarm device 13 through a connector 14 described in detail later. The alarm 13 includes a buzzer 12, and the buzzer 12 sounds when the moisture sensor 11 detects a blood leak. In this embodiment, the blood detection device 10 for artificial dialysis is used for monitoring blood leakage during artificial dialysis. This blood detection device 10 for artificial dialysis generally detects leakage of infusion during infusion. It goes without saying that it can be used as a monitoring device.

1. Moisture sensor structure

  FIG. 2 is a cross-sectional view of the moisture sensor 11. FIG. 3 is an exploded perspective view schematically showing the structure of the moisture sensor 11. The upper side in FIG. 3 is the side on which the patient's arm is placed in a state where the moisture sensor 11 is used.

  As shown in FIG. 3, the moisture sensor 11 includes an electrode sheet 15, a filter sheet 16, and a water-permeable sheet 17. This water-permeable sheet 17 has water permeability and constant water retention. The electrode sheet 15 is formed so as to exhibit insulation in a dry state and to exhibit conductivity in a state containing moisture. The electrode sheet 15 includes a base sheet 18 (see FIG. 3) and a pair of electrodes 19 (19a, 19b) disposed on the base sheet 18. The electrode sheet 15 contains an electrolyte substance having high hydrophilicity so that the conductivity is increased when the electrode sheet 15 contains moisture.

  The material which comprises the base sheet 18 of the electrode sheet 15 is not specifically limited. In short, the base sheet 18 has air permeability, the electrode 19 is stably supported, does not easily break with a small force, and has a water resistance that does not swell or dissolve by self-absorbing moisture in the air. It only has to have. The base sheet 18 includes an upper base sheet 20 and an underlay base sheet 21. The upper base sheet 20 is positioned on the side where the patient's blood comes into contact first, and the lower base sheet 21 is positioned on the side where the electrode 19 is supported from below.

  The base sheet 18 on which the electrodes 19 are disposed exhibits a substantially insulating property in a dry state. The base sheet 18 is preferably hydrophilic and flexible. As the material of the base sheet 18, materials such as polyethylene, polypropylene, nylon, polyethylene terephthalate, polycarbonate, polyvinyl chloride, polyvinylidene chloride, polyimide, silicone rubber, silicone resin, cloth, paper and the like can be adopted. In particular, as a material for the base sheet 18, paper, cloth, nonwoven fabric, or the like made of hydrophilic cellulose fibers is preferably used. In the present embodiment, the base sheet 18 is made of Japanese paper. This is because Japanese paper is strong, thin, hydrophilic, and environmentally friendly.

  The underlay base sheet 21 according to the present embodiment has a three-layer structure, and includes a reinforcing sheet 22, an upper sheet 23, and a lower sheet 24. An upper sheet 23 is disposed on the front surface side of the base sheet 18 with the reinforcing sheet 22 interposed therebetween, and a lower sheet 24 is disposed on the rear surface side. The upper sheet 23, the lower sheet 24, and the reinforcing sheet 22 are integrally formed. The underlay base sheet 21 is stable without being wrinkled while maintaining flexibility even when the electrode 19 is printed as will be described later.

  FIG. 4 is a diagram schematically showing a cross-sectional structure of the reinforcing sheet 22.

  The reinforcing sheet 22 includes a base fabric 25 and a nonwoven fabric 26 laminated on the base fabric 25. In the figure, the electrode 19 (see FIG. 3) is present on the upper side, and the moisture sensor 11 is the side on which the patient places his arm. The reinforcing sheet 22 has air permeability. The base fabric 25 is mainly composed of sheet-like polyethylene, and is mixed with calcium carbonate. By mixing the calcium carbonate particles, a large number of fine holes 27 are formed through the sheet-like polyethylene. The diameter of the fine hole 27 is set to about 1 μm to 100 μm. Moreover, the said nonwoven fabric 26 is comprised because a pulp fiber entangles irregularly, and has sufficient air permeability. Therefore, water vapor can pass through the non-woven fabric 26 and the base fabric 25, but water droplets cannot pass through the base fabric 25. The thickness dimension of the reinforcing sheet 22 is not particularly limited. As a material constituting the base fabric 25, a resin film such as polyester, polypropylene, polyvinyl chloride or the like can be used instead of the polyethylene. This is because, by using these materials, the reinforcing sheet 22 has relatively high rigidity and can be provided with flexibility. In addition, the said nonwoven fabric 26 may be abbreviate | omitted.

  Since the underlay base sheet 21 has the laminated structure as described above, the work of attaching the electrode 19 as described later becomes easy. In the present embodiment, the upper sheet 23 and the lower sheet 24 are made of Japanese paper. However, the upper sheet 23 and the lower sheet 24 may be made of other materials. The upper sheet 23 and the lower sheet 24 are fixed by an adhesive. The adhesive is applied to the upper and lower surfaces of the reinforcing sheet 22, and the upper sheet 23 and the lower sheet 24 are attached to the reinforcing sheet 22. Thereby, these adhesiveness is ensured.

  The size of the base sheet 18 is not particularly limited, but a standard sheet of about A4 size of plain paper is standard. The thickness of the base sheet 18 can be set to 0.5 mm or more and 3 mm or less. This is because, if the thickness of the base sheet 18 is about this level, the flexibility of the base sheet 18 is ensured and the handling is convenient. However, the thickness of the base sheet 18 differs depending on the material of the electrode 19 and the base sheet 18 and the laminated structure. The base sheet 18 is formed so as to exhibit hydrophilicity as a whole.

  As shown in FIG. 3, the electrode sheet 15 is configured by arranging the pair of electrodes 19 a and 19 b on the base sheet 18. Specifically, after a predetermined electrolyte solution has permeated into the upper base sheet 20 and the lower base sheet 21, the upper base sheet 20 and the lower base sheet 21 are dried. Further, the pair of electrodes 19 a and 19 b are arranged in parallel on the upper sheet 23, and the upper base sheet 20 is aligned with the lower base sheet 21. That is, the electrodes 19 a and 19 b are sandwiched between the underlay base sheet 21 and the overlay base sheet 20. In addition, the electrode sheet 15 is arranged on the base sheet 18 after the pair of electrodes 19a and 19b are arranged in parallel on the upper sheet 23 and sandwiched between the upper sheet 23 and the upper base sheet 20. The electrolyte solution may be infiltrated and dried.

  The electrolyte solution preferably contains a hydrophilic polymer as will be described later. Examples of the electrolyte of the electrolyte solution include inorganic salts such as sodium chloride, potassium chloride and sodium nitrate, ammonium salts, alkali metal salts of fatty acids, and alkali metal salts of glutamic acid. Since these salts dissolve in water and ionize, they exhibit conductivity. Among these electrolytes, sodium chloride is particularly preferable. This is because sodium chloride is a strong electrolyte, has a small difference in solubility depending on temperature, and is inexpensive and stable. More preferably, the salt is a water-soluble liquid having a content of 10% by mass to 21% by mass.

  By the way, in general, when moisture is contained in the electrode sheet 15, if a small amount of moisture is connected between the local portions of the electrodes 19 a and 19 b, there is a possibility of erroneous detection as the moisture sensor 11. There is. For example, when the moisture sensor 11 is used as a sensor for detecting blood leakage in an artificial dialysis treatment, if the electrodes 19a and 19b are immediately conducted due to a small amount of sweat from the patient's arm, the blood As a device for monitoring leaks, malfunctions will occur. Therefore, in order to accurately detect bleeding in the artificial dialysis treatment, a certain amount of water (blood), for example, about 5 cc to 10 cc, is spread between the electrodes 19 a and 19 b in a relatively wide range in the electrode sheet 15. It needs to be conducted. In the present embodiment, since the electrolyte solution containing the hydrophilic polymer is used in the electrode sheet 15, the electrodes 19a and 19b are electrically connected on the condition that there is a certain amount of bleeding. As a result, erroneous detection of the moisture sensor 11 is reliably prevented.

  Furthermore, since the electrolyte solution containing the hydrophilic polymer is used, when the electrode sheet 15 absorbs moisture, the electrode sheet 15 is easily wetted uniformly. Further, when the moisture is dried, the electrodes 19a and 19b in the electrode sheet 15 are electrically insulated. This hydrophilic polymer is preferably water-soluble. Examples of the hydrophilic polymer include cellulose, starch, pectin and the like. In particular, starches such as rice starch, wheat starch, potato starch and corn starch are preferred. This is because they also function as an adhesive.

  Among these starches, potato starch is more preferably used because of its high degree of adhesion. Specific examples of the water-soluble adhesive 28 containing an electrolyte (see FIGS. 2 and 3) include, for example, potato 1 mass% to 5 mass%, sodium chloride 15 mass% to 21 mass%, and water 74 mass%. A paste composed of about 84% by mass or less is more preferable. The amount of this salt may be an amount in the vicinity of saturated solubility that can be dissolved in water at room temperature. This glue is mixed by adding water, salt and potato starch as ingredients, and stirred while heating. When this stirred product exhibits a uniform consistency, it is cooled to a conductive paste.

  When the electrode 19 is formed as a separate member and is sandwiched between the base sheets 18, the electrode 19 may be, for example, 0.3 mm or less in thickness, and flexible thin conductive wires may be wired in parallel at a predetermined interval. The electrode 19 is preferably formed in a film shape and has flexibility. The electrode 19 may be formed of a conductive thread or a thin metal wire. Examples of the conductive yarn include those obtained by combining metal fibers. For example, when the base sheet 18 is made of woven fabric, nonwoven fabric, or the like, the electrode 19 may be sewn directly to the base sheet 18. In addition, the electrode 19 may be formed of a tape-like conductive plate that is thinly extended, such as an aluminum foil.

  The electrode sheet 15 is specifically formed as follows.

  As shown in FIG. 3, the electrode 19 is wired on the base sheet 21. Thereafter, the base sheet 20 is placed on the base sheet 21. At this time, the conductive adhesive 28 is used, and the electrode 19 is securely adhered to the underlay base sheet 21 and the underlay base sheet 20. Thereby, the stable operation | movement of the moisture sensor 11 is implement | achieved. Since the conductive adhesive 28 contains a polymer component, the space between the pair of electrodes 19a and 19b is moistened in proportion to the amount of water absorbed by the electrode sheet 15, and the water absorbed by the electrode sheet 15 is absorbed. When a certain amount is reached, the electrodes 19a and 19b are electrically connected. By conducting between the electrodes 19a and 19b, the electrical conductivity between the electrodes 19a and 19b rapidly decreases. Therefore, the moisture sensor 11 can reliably detect the presence of blood (the presence or absence of bleeding during treatment).

  The conductive adhesive 28 is applied or infiltrated into the overlay base sheet 20 that is a hydrophilic sheet. Since the overlay base sheet 20, the electrode 19, and the underlay base sheet 21 are integrated, it is preferable that the surface of the overlay base sheet 20 facing the electrode 19 is covered with the conductive adhesive 28. . The conductive adhesive 28 is applied to the entire lower surface of the upper base sheet 20, and the upper base sheet 20 is attached to the lower base sheet 21 to which the electrode 19 is attached, whereby the base sheet 18 is easily integrated. . More specifically, it is preferable that the conductive adhesive 28 is configured as a substantially saturated amount of salt-containing starch paste, which is sprayed or applied to the base sheet 20. And this base sheet 20 is affixed to the base sheet 21.

  In the present embodiment, the electrode 19 is printed on the base sheet 18. Conductive ink is used in this printing. As the conductive ink composing the electrode 19, a conductive metal paste is suitable. As the conductive metal paste, fine particles such as gold, silver, platinum, palladium, and copper are dispersed in a binder resin and formed into a paste. This conductive metal paste is printed on the base sheet 18. For this reason, the base sheet 18 is preferably made of a heat-resistant material such as Japanese paper or polyimide. As FIG.1 and FIG.3 shows, the electrode 19a and the electrode 19b are parallel at equal intervals. The ends of these electrodes 19a and 19b constitute an electrode terminal 30 made of the same metal paste. The electrodes 19 a and 19 b meander so as to be uniformly arranged on almost the entire surface of the base sheet 18. Thus, since the electrode 19 is configured by printing with conductive ink, the electrode sheet 15 having a uniform structure can be easily manufactured.

  If the metal particles of the metal paste are uniformly dispersed as ultrafine particles, the electrode 19 is fired at a temperature of about 120 ° C. to 240 ° C. Thereby, the electrode 19 can be printed and formed on the base sheet 18 without damaging the base sheet 18. As shown in FIG. 3, in the present embodiment, an electrode 19 made of silver paste is printed on the base sheet 18. The width dimension of the electrode 19 to be printed is set to about 2 mm.

  Moreover, in this embodiment, the electrical resistance element 31 is provided so that it may span between a pair of electrodes 19a and 19b. Thereby, the electrodes 19a and 19b are electrically connected. By disposing the electric resistance element 31, the electrode 19 a is energized between the electrodes 19 a and 19 b even when the electrode sheet 15 does not contain moisture. The electric resistance element 31 will be described in detail later. It is necessary to apply a high voltage that the moisture sensor 11 is in an operable state (no disconnection or the like has occurred in the electrode 19) by the conduction between the electrodes 19a and 19b by the electric resistance element 31. Can be easily confirmed without.

  The resistance value of the electric resistance element 31 is usually set to about 20 kΩ to 5 kΩ. For this reason, when the electrode sheet 15 is in a dry state, the electrical resistance between the electrodes 19a and 19b is extremely large, and when moisture is present in the electrode sheet 15, the electrical resistance between the electrodes 19a and 19b rapidly decreases. It will be. Therefore, the moisture sensor 11 can reliably detect the presence of moisture, that is, the presence or absence of bleeding.

  The electric resistance element 31 can also be printed using a conductive ink. Carbon ink is preferably used as the conductive ink constituting the electric resistance element 31. The carbon used in the carbon ink is preferably a non-graphitizable material such as phenol resin, furfuryl alcohol, vinylidene chloride, cellulose, wood and the like. This conductive ink is prepared by kneading carbon powder and a binder made of a resin such as phenol or epoxy into a paste. The conductive ink constituting the electric resistance element 31 is printed on the surface of the upper sheet 23 of the underlying base sheet 21. As shown in FIG. 3, the electric resistance element 31 is printed on the upper sheet 23 in the vicinity of the end of the other side opposite to the side on which the electrode terminal 30 is disposed. The electric resistance element 31 is printed over the entire width direction of the upper sheet 23. The width dimension of the electric resistance element 31 may be set to about 3 mm to 5 mm. In the present embodiment, the electrode 19 is printed so as to cross over the electric resistance element 31.

  The filter sheet 16 is disposed on the electrode sheet 15 thus prepared. The filter sheet 16 has water repellency and includes a large number of small holes 32. The filter sheet 16 can pass moisture only through the small holes 32. Therefore, when there is a sufficient amount of moisture (blood) to wet a certain area on the filter sheet 16, the blood easily passes through the small holes 32 of the filter sheet 16. The filter sheet 16 is disposed so as to cover the entire effective area of the electrode sheet 15. Here, the effective area of the electrode sheet 15 is an area in which moisture can be detected, and an end portion of a blank that does not exhibit conductivity is excluded from the effective area.

  The filter sheet 16 may be simply inserted between the electrode sheet 15 and the water-permeable sheet 17, but the filter sheet 16 is preferably integrated with the electrode sheet 15 and the water-permeable sheet 17. Thereby, handling of the filter sheet 16 becomes easy. The filter sheet 16 may be bonded between the electrode sheet 15 and the water-permeable sheet 17 via an adhesive. However, even when the filter sheet 16 is integrated with the electrode sheet 15 or the like, it is preferable that the filter sheet 16 has flexibility so that it can follow the deformation of the electrode sheet 15 or the like.

  The filter sheet 16 may be composed of, for example, an ethylene vinyl acetate copolymer film. This ethylene vinyl acetate copolymer film is rich in flexibility and can be heat-bonded to the base sheet 18 or the like. This heat bonding can satisfactorily integrate the filter sheet 16 with the electrode sheet 15 or the like. Instead of the ethylene vinyl acetate copolymer film, a polytetrafluoroethylene film may be employed as the material of the filter sheet 16. The thickness of the filter sheet 16 is preferably 10 μm or more because it is easily damaged when it is too thin. More preferably, it is 20 micrometers or more, Furthermore, it is 30 micrometers or more. If the filter sheet 16 is too thick, the flexibility becomes poor, and therefore it is preferably about 100 μm or less. From this viewpoint, the thickness of the filter sheet 16 is more preferably 80 μm or less. More preferably, it is 60 μm or less.

  The shape and size of the small holes 32 provided in the filter sheet 16 are not particularly limited as long as the purpose of allowing a small amount of moisture to pass therethrough is achieved. The small holes 32 may be constituted by eyes formed by knitting fibers in a lattice shape. The large number of small holes 32 are usually arranged in a distributed manner at equal intervals. If the small holes 32 are too small, they are likely to be filled with foreign matters and the like, and therefore, the inner diameter of the small holes 32 is preferably 1.0 mm or more. More preferably, it is 1.2 mm or more, More preferably, it is 1.5 mm or more.

If the small holes 32 are too large, the filter sheet 16 has a high probability of easily passing moisture (sweat, etc.) other than the liquid to be detected (blood). For this reason, it is preferable that the internal diameter dimension of the small hole 32 is 4.0 mm or less. More preferably, the inner diameter of the small hole 32 is 3.5 mm or less, and more preferably 3.0 mm or less. The interval between the adjacent small holes 32 is appropriately set with a standard of about 10 mm in the case of the small holes 32 having an inner diameter of 2.0 mm. If the density of the small holes 32 is too small, it is difficult for blood to pass through and detection is delayed. For this reason, the number of small holes 31 per 100 cm ² area of the filter sheet 16 is preferably set to about 50 or more and 500 or less.

  The water-permeable sheet 17 disposed on the filter sheet 16 is preferably capable of allowing moisture to pass therethrough with water retention by a network or a structure such as micropores. The water-permeable sheet 17 having water permeability and water retention capacity can retain a certain amount of water, but allows water exceeding the water retention amount to pass therethrough. Examples of the material of the water-permeable sheet 17 include synthetic fibers such as polyvinyl alcohol and polyester, or natural fibers such as cellulose, cotton, hemp, and wool. As a material constituting the water-permeable sheet 17, these woven fabrics, nonwoven fabrics, or papers are used. In particular, as a material for the water-permeable sheet 17, a nonwoven fabric made of cotton, pulp fiber, or cellulose fiber is more preferably used. The water-permeable sheet 17 exerts a buffer effect that holds or disperses a part of the blood as the liquid to be detected. On the other hand, sweat or the like from the patient's arm occurs in a relatively wide range as compared with bleeding from the needle for artificial dialysis, so that the water-permeable sheet 17 keeps moisture such as sweat and diffuses as a gas at the same time. Thus, it is possible to prevent moisture from being fed into the filter sheet 16.

  FIG. 5 is a wiring diagram showing the basic configuration of the blood detector 10 for artificial dialysis using the moisture sensor 11.

  The blood detection device 10 for artificial dialysis includes divided resistance circuits C1, C2, and C3. In the blood detector 10 for artificial dialysis, the output values of the resistance circuits C1 to C3 are compared, and based on the results, five types of signals are alternatively generated as described later.

  In FIG. 5, the resistance R0 of the moisture sensor 11 is set to 20 kΩ. The resistor circuit C1 includes a power source and a resistor r1 (= 20 kΩ), the resistor circuit C2 includes a resistor r2 (= 100 kΩ) and a variable resistor R1 (= 10 kΩ to 20 kΩ), and the resistor circuit C3 includes a resistor r3 (= 20 kΩ). ) And a variable resistor R2 (= 50 kΩ to 100 kΩ). When the wiring of the blood detector for artificial dialysis 10 is normally connected, the voltage V0 of the power supply is distributed between the voltage acting on the variable resistor R1 and the voltage acting on the resistor r1, and the negative voltage of the comparator H1. The signal is input to the signal input terminal and the positive signal input terminal of the comparator H2. When the moisture sensor 11 is not connected or has a poor contact, a value corresponding to the voltage drop caused by the resistor r1 of the power supply voltage V0 is input to the comparator H1 and the comparator H2. In the resistor circuit C2, for example, when the variable resistor R1 is 20 kΩ, a voltage of V0 × R1 / (r2 + R1) = V0 / 6 is applied to the negative signal input terminal of the comparator H2. In the resistor circuit C3, when the variable resistor R2 is 100 kΩ, a voltage of V0 × R2 / (r3 + R2) = V0 × 5/6 is applied to the positive signal input terminal of the comparator H1.

  The power supply V0 is connected to the output terminal of the comparator H1 through a resistor r4 (= 470 kΩ), a red light emitting diode LR1, and a buzzer BZ1. The power supply is connected to the output terminal of the comparator H2 through a resistor r4 (= 470 kΩ), a red light emitting diode LR2, and a buzzer BZ2. The voltage V0 of the power supply is grounded through a resistor r4 and a resistor r5 (= 470 kΩ). The output terminals of the comparators H1 and H2 are input to the signal input terminals of the two-input AND gate AG. The output terminal of the two-input AND gate AG is connected to the blue light emitting diode LB.

  When the moisture sensor 11 is not connected, the output of the comparator H1 is at a low level. The low level output of the comparator H1 causes the red diode LR1 to emit light and sound the buzzer BZ1. When the moisture sensor 11 is connected, the two outputs of the comparator H1 and the comparator H2 become high level. The output of the two-input AND gate AG to which these two signals are input switches to a high level, causing the blue light emitting diode LB to emit light. When the moisture sensor 11 contains blood and the resistance between the electrodes 19 is reduced to several tens of Ω, the output of the comparator H2 becomes low, and the red light emitting diode LR2 and the buzzer BZ2 are activated.

2. Connector structure

  6 and 7 are perspective views of the connector 14.

  As shown in FIG. 6, the connector 14 is attached to and detached from the moisture sensor 11, and has a cord 29 connected to the alarm device 13.

  The connector 14 includes a casing 33, a lever 34 provided on the casing 33, and a clip 41. The lever 34 can rotate with respect to the casing 33, and as described later, cooperates with the casing 33 to sandwich one end of the moisture sensor 11 and the electrode 19 of the moisture sensor 11. It is designed to be electrically connected.

  The clip 41 can sandwich the other end of the moisture sensor 11. The clip 41 can be held with a constant holding force across the other end of the moisture sensor 11. Specifically, the moisture sensor 11 laid under the patient's arm is wound around the patient's arm, and the other end of the moisture sensor 11 is sandwiched between the clips 41. The connector 14 is characterized in that the clip 41 is provided. If it is detected that the moisture sensor 11 is detached from the clip 41, it is predicted that the patient has pulled the moisture sensor 11 during artificial dialysis. If this is anticipated, the nurse or the like can grasp the possibility that a needle pull-out accident will occur thereafter, and can prevent the needle pull-out accident in advance.

  FIG. 7 shows a state where the lever 34 is opened. As shown in the figure, the lever 34 includes a pair of leg portions 35. The leg portion 35 is attached to the casing 33 via a support shaft 36. The leg portion 35 can rotate about the support shaft 36 and is rotatable with respect to the casing 33. That is, the posture of the lever 34 is freely changeable between a posture lying on the casing 33 as shown in FIG. 6 and a posture standing on the casing 33 as shown in FIG. The posture in which the lever 34 has fallen with respect to the casing 33 is defined as a “falling posture”, and the posture in which the lever 34 stands with respect to the casing 33 is defined as a “standing posture”.

  The casing 33 is made of resin. The casing 33 is formed in a rectangular plate shape as a whole. However, the corner portion of the casing 33 is chamfered, and the corner portion of the casing 33 is formed into a smooth curved surface. For this reason, nurses, caregivers, and patients can obtain a smooth and gentle touch when touching the casing 33. As shown in FIG. 7, a stepped portion 37 is formed on the front side of the casing 33. A pair of terminal accommodating portions 38 are provided in the inner depth of the casing 33 continuously from the step portion 37. The terminal accommodating portion 38 is composed of an accommodating space formed on the inner back side of the casing 33 continuously to the wall surface 39 of the stepped portion 37. The pair of leg portions 35 of the lever 34 is fitted into the terminal accommodating portion 38.

  An electrode connecting member 40 (an example of a “conductive electrode connecting member” in the present invention) is fitted in each terminal accommodating portion 38. The electrode connecting member 40 is disposed below the lever 34. Specifically, the electrode connecting member 40 is disposed below the leg portion 35 of the lever 34 and is always in contact with the leg portion 35. As will be described in detail later, the electrode connecting member 40 is formed by bending or bending an elongated strip-like member into a substantially U shape, and the tip portion thereof extends from the terminal accommodating portion 38 to the stepped portion 37. It protrudes to the side and is exposed (see FIG. 7).

  FIG. 8 is a diagram illustrating a positional relationship between the electrode connecting member 40 disposed in the casing 33 and the leg portion 35 of the lever 34.

  As shown in FIGS. 7 and 8, the electrode connecting member 40 fitted in the terminal accommodating portion 38 is made of a stainless steel plate. But the material which comprises the electrode connection member 40 is not limited to a stainless steel plate, A different thing can be employ | adopted if it has a metal plate and other electroconductivity. In the present embodiment, the elongated strip-shaped stainless steel plate is curved at a substantially central portion and formed in a substantially U shape as a whole.

  The electrode connecting member 40 includes a main body 44 having a pair of arms 42 and 43 and a piercing blade 45 provided at the tip of one arm 42. As described above, since the electrode connecting member 40 is formed in a substantially U shape, the pair of arms 42 and 43 face each other. In the present embodiment, the piercing blade 45 includes four sharp needles. The piercing blade 45 projects from one arm 42 to the other arm 43 side. The other arm 43 has a hole 46 as shown in FIG. When the main body 44 is elastically deformed and one arm 42 is displaced toward the other arm 43, the piercing blade 45 is inserted into the hole 46 as described later. The piercing blade 45 is also made of stainless steel. In the present embodiment, the piercing blade 45 is fixed to the main body 44 by spot welding. However, the piercing blade 45 may be provided integrally with the main body 44.

  Since the electrode connecting member 40 is made of stainless steel, the electrode connecting member 40 can be elastically deformed. That is, the opposing arms 42 and 43 can freely change their posture between a separated posture as shown by the solid line in FIG. 8 and a close posture close to each other as shown by the two-dot chain line in FIG. Can do. The piercing blade 45 is fitted into the hole 46 when the opposing arms 42 and 43 are in the proximity posture. The cord 29 is connected to the pair of electrode connection members 40. Therefore, the determination of whether each electrode connecting member 40 is in an insulated state or a conductive state is easily performed by applying a predetermined voltage between the two.

  The lever 34 is also made of resin. The lever 34 is formed in a thin plate shape as a whole. However, the corner portion of the lever 34 is also chamfered in the same manner as the casing 33 and is formed into a smooth curved surface. Therefore, a nurse, a caregiver, or a cared person can obtain a smooth and gentle touch when touching the lever 34.

  As described above, the lever 34 changes its posture between the lying posture and the standing posture. When the lever 34 is in the standing posture, that is, when the leg portion 35 of the lever 34 is in the posture shown by the solid line in FIG. 8, one arm 42 is separated from the other arm 43. Further, when the lever 34 is in the lying posture, that is, when the leg portion 35 of the lever 34 is in the posture indicated by the two-dot chain line in FIG. 8, one arm 42 is close to the other arm 43. .

  The leg portion 35 includes contact surfaces 47 and 48 that contact the arm 42. When the lever 34 is in the standing posture, the contact surface 47 contacts the arm 42. At this time, the contact surface 47 receives a predetermined elastic force from the arm 42. As shown in FIG. 8, the support shaft 36 that supports the lever 34 is disposed behind the center of the contact surface 47 in a state where the contact surface 47 is in contact with the arm 42. Therefore, when the lever 34 is in the standing posture, the lever 34 is urged in a direction to rotate counterclockwise about the support shaft 36. That is, the lever 34 is held in the standing posture. On the other hand, when the lever 34 is in the lying posture, the contact surface 48 contacts the arm 42. At this time, the contact surface 48 receives a predetermined elastic force from the arm 42. As shown in FIG. 8, the support shaft 36 that supports the lever 34 is disposed on the front side of the center of the contact surface 48 in a state where the contact surface 48 is in contact with the arm 42. Therefore, the lever 34 is urged in a direction that rotates clockwise around the support shaft 36. That is, the lever 34 is held in the lying posture.

  As shown in FIGS. 6 and 7, a finger hook 49 is formed at the center of the lever 34. The finger hook portion 49 is configured by the upper edge portion 50 of the lever 34 bulging. By providing the finger hooking portion 49, even when the lever 34 is in the lying posture (see FIG. 6), a nurse or the like can easily hook the finger on the lever 34. Therefore, the operation of the lever 34 is simplified.

  FIG. 9 is an enlarged perspective view of the connector 14 and shows the structure of the back surface 51 of the casing 33 in detail.

  In the present embodiment, a plurality of protrusions 52 are formed on the back surface 51 of the casing 33. The outer surface of the protrusion 52 is formed into a smooth curved surface, so that when a nurse or the like touches the protrusion 52, a touch that is gentle to the skin can be obtained. However, the shape of the protrusion 52 is not particularly limited, and may be any shape that does not receive a strong stimulus when touched by a nurse or the like. In the present embodiment, the protrusions 52 are arranged substantially evenly on the back surface 51, but the number of the protrusions 52 is not particularly limited.

  As shown in FIG. 6, the outer dimensions of the casing 33 are set such that the vertical dimension a is 35 mm, the horizontal dimension b is 44 mm, and the height dimension c is 10 mm. However, the vertical dimension a can be set to 25 mm to 45 mm, the horizontal dimension b can be set to 35 mm to 60 mm, and the height dimension c can be set to 5 mm to 15 mm. The effect by setting the casing 33 to such a dimension will be described later.

  As shown in FIG. 1, the alarm 13 is connected to the connector 14. The alarm 13 is a known one that has been generally used. The alarm device 13 incorporates a voltage device (not shown), and this voltage device applies a constant voltage between the pair of electrode connection members 40 (see FIG. 8). The alarm 13 measures the current flowing between the pair of electrode connecting members 40, and outputs a signal for operating the buzzer 12 when the magnitude of the current exceeds a predetermined value. The alarm 13 outputs a signal for operating the buzzer 12 even when the current flowing between the pair of electrode connecting members 40 becomes zero.

  FIG. 10 is an enlarged perspective view of a main part of the connector 14 and shows a state where the clip 41 is opened. FIG. 11 is an enlarged exploded perspective view of the connector 14 and shows a state in which the clip 41 is removed from the connector 14. FIG. 12 is an enlarged perspective view of the clip 41.

  As shown in FIG. 12, the clip 41 includes a casing 53, a sandwiching plate 54, and a switch 55.

  The casing 53 is made of the same resin as that constituting the casing 33. The casing 53 is formed in a rectangular plate shape as a whole. The casing 53 includes a base portion 56 and a fitting portion 57 that is continuous with the base portion 56. The base 56 has a pair of support plates 58. The support plate 58 protrudes from both ends of the base portion 56 and supports the clamping plate 54 as will be described later. In addition, the protrusion 52 is provided also in the back surface of the casing 53 (refer FIG. 4).

  The base 56 includes an inclined surface 59 on the back side. When the sandwiching plate 54 is in the open posture described later, the sandwiching plate 54 contacts the inclined surface 59. The fitting portion 57 is formed in a rectangular plate shape and protrudes forward from the base portion 56. As shown in FIG. 11, the fitting portion 57 is fitted into a seat portion 60 provided behind the casing 33. The seat portion 60 is composed of a recess formed by cutting out the casing 33. In the present embodiment, a part of the electrode connecting member 40 is exposed in the seat portion 60.

  As shown in FIGS. 10 and 11, the sandwiching plate 54 includes a flat plate portion 70 and a pair of leg portions 71. The sandwiching plate 54 is made of the same resin as that constituting the casing 53. A protrusion 72 is provided on the upper surface of the flat plate portion 70. The protrusion 72 has the same configuration as the protrusion 52 provided on the casing 33. The leg portion 71 projects from the substantially central portion of the flat plate portion 70. Each leg 71 is supported by the support plate 58 via a support shaft 73. The pair of leg portions 71 are fitted between the pair of support plates 58.

  The leg 71 can rotate around the support shaft 73. Therefore, the sandwiching plate 54 can change its posture with respect to the fitting portion 57. That is, as shown in FIGS. 11 and 6, the holding plate 54 can change its posture between a closed posture in contact with the fitting portion 57 and an open posture in which the holding plate 54 is separated from the fitting portion 57 as shown in FIG. 10. It has become. In the present embodiment, since the inclined surface 59 is provided in the base portion 56, when the sandwiching plate 54 is in the open posture, the sandwiching plate 54 contacts the inclined surface 59, and the open posture is maintained. Is done. In the present embodiment, a torsion coil spring 74 is provided between the support plate 58 and the sandwiching plate 54. Thereby, the clamping board 54 is always urged | biased by the fixed attitude | position by the fixed elastic force. For example, when the nurse or the like presses the rear end portion of the sandwiching plate 54, the sandwiching plate 54 changes from the closed posture to the open posture.

  A recess 75 is provided at the center of the inner surface of the sandwich plate 54. In the present embodiment, the recess 75 is circular and has a predetermined inner diameter and depth. As shown in FIG. 10, when the clamping plate 54 changes from the open position to the closed position, a contact release bar 76 described later enters the recess 75. The shape of the recess 75 is not particularly limited, and may be any shape as long as the contact release bar 76 can enter the recess 75 when the sandwiching plate 54 is in the closed position.

  The switch 55 is provided in the fitting portion 57. The switch 55 includes a pair of thin metal plates 77 and 78 (an example of the “electrode plate” in the present invention) and the contact release bar 76. The thin metal plates 77 and 78 are disposed at the right end and the left end of the fitting portion 57, respectively. The thin metal plate 77 is made of a long and narrow stainless steel plate. As shown in FIG. 10, the thin metal plate 77 covers the upper surface and the side surface of the right end portion of the fitting portion 57, and wraps around the lower surface of the fitting portion 57 as shown in FIG. 12. A contact portion 79 is formed on the lower surface side end portion of the metal thin plate 77. The contact portion 79 is formed by raising a part of the metal thin plate 77.

  Similarly to the metal thin plate 77, the metal thin plate 78 is made of a long and narrow strip-shaped stainless steel plate. As shown in FIG. 10, the thin metal plate 78 covers the upper surface and the side surface of the left end portion of the fitting portion 57, and wraps around the lower surface of the fitting portion 57 as shown in FIG. 12. The thin metal plate 78 extends to the right end side of the fitting portion 57 so as to overlap the thin metal plate 77. The lower surface side end of the thin metal plate 78 is in contact with the contact portion 79, and the contact points of the thin metal plates 77 and 78 are formed in the contact portion 79. Since the metal thin plates 77 and 78 are made of thin stainless steel plates, they are rich in elasticity. Accordingly, the metal thin plate 78 is normally elastically biased so as to contact the contact portion 79 of the metal thin plate 77. That is, the switch 55 is configured as a normally closed type switch.

  In the present embodiment, the metal thin plates 77 and 78 are made of stainless steel plates, but the present invention is not limited to this. In short, any material having conductivity and rich in elasticity is suitable as a material for the metal thin plates 77 and 78.

  The thin metal plate 78 includes the contact release bar 76. The contact release bar 76 is erected substantially at the center of the thin metal plate 78 and passes through the fitting portion 57 and is exposed on the upper surface 80 of the fitting portion 57 as shown in FIG. As will be described later, the moisture sensor 11 is sandwiched between the fitting portion 57 and the sandwiching plate 54, but the contact release bar 76 is pressed against the moisture sensor 11 in this state. The contact release bar 76 pressed by the moisture sensor 11 slides downward in FIG. 10 and presses the thin metal plate 78. Thereby, the contact between the metal thin plate 78 and the metal thin plate 77 is cut off. That is, the switch 55 is turned off. When the sandwiching plate 54 changes to the open position (the state shown in FIG. 10), the contact release bar 76 is pushed by the elastic force of the thin metal plate 78, and both the thin metal plates 77 and 78 come into contact at the contact portion 79. That is, the switch 55 is turned on. When the moisture sensor 11 is detached from the clip 41 in a state where the clip 41 holds the moisture sensor 11, the contact release bar 76 enters the recess 75, and the switch 55 is turned on. That is, the contact release bar 76 is pushed by the elastic force of the thin metal plate 78, and the two thin metal plates 77 and 78 come into contact with each other at the contact portion 79.

  In the present embodiment, as shown in FIG. 10, a plurality of protrusions 81 are provided on end portions of the metal thin plates 77 and 78 (portions disposed on the upper surface 80 of the fitting portion 57). As a result, the moisture sensor 11 is securely sandwiched between the clips 41, and the moisture sensor 11 is not easily detached from the clip 41 and is held with a certain holding force. Note that the protrusion 81 may be omitted. In that case, in order to achieve a certain holding force, the spring force of the torsion coil spring 74 may be set large, or the upper surface 80 of the fitting portion 57 may be formed to be rough.

3. How to use blood detector for artificial dialysis

  This blood detector 10 for artificial dialysis is used in the following manner. FIG. 13 shows a use state of the blood detection device 10 for artificial dialysis.

  As shown in the figure, the moisture sensor 11 is used for monitoring blood leakage in an artificial dialysis treatment. The moisture sensor 11 is laid in a range where blood can be received when blood leaks from the injection needles provided at the tips of the artificial dialysis tubes 83 and 84. Since the moisture sensor 11 is thin and flexible as described above, the moisture sensor 11 can be wound around a patient's arm to which two tubes 83 and 84 for artificial dialysis are attached.

  First, the moisture sensor 11 is placed under the arm of a patient undergoing artificial dialysis. The connector 14 is attached to the one end 61 of the moisture sensor 11. The moisture sensor 11 is wound around the patient's arm, and the other end 62 of the moisture sensor 11 is sandwiched between the clips 41.

  The connector 14 sandwiches and holds the moisture sensor 11 with the electrode connecting member 40. Specifically, for example, the nurse operates the lever 34 of the connector 14 to change to a standing posture. The nurse arranges the moisture sensor 11 between the arms 42 and 43 of the electrode connecting member 40 and changes the lever 34 to the lying posture. Thereby, the piercing blade 45 pierces the electrode 19 (that is, silver paste) of the moisture sensor 11, and the electrode connecting member 40 is bridged between the pair of electrodes 19 a and 19 b printed on the electrode sheet 15. Thus, since the piercing blade 45 pierces the electrode sheet 15, the connector 14 is fixed to the moisture sensor 11 easily and reliably. Further, since the piercing blade 45 only pierces the moisture sensor 11, the piercing blade 45 is easily extracted from the moisture sensor 11. Therefore, since the connector 14 is easily detached from the moisture sensor 11, the replacement operation of the moisture sensor 11 is performed easily and quickly.

  As described above, the electrode connecting member 40 pierces the electrode sheet 15. At this time, the piercing blade 45 provided on one arm 42 is fitted into the hole 46 provided on the other arm 23 (see FIG. 7). ), The electrode connection member 40 penetrates the electrode sheet 15 more securely and is fixed to the moisture sensor 11. Moreover, the electrode connecting member 40 is elastically deformed, and the pair of arms 42 and 43 are changed to the separated posture or the close posture. Therefore, when the nurse changes the lever 34 to the standing posture, the electrode connecting member 40 has an advantage that it immediately separates from the electrode sheet 15.

  In the present embodiment, since the connector 14 is made of resin, the connector 14 can gently contact human skin. In addition, there is an advantage that the nurse and the like can attach and detach the connector 14 to and from the moisture sensor 11 very easily only by the operation of raising or lowering the lever 34.

  As described above, when the lever 34 is in the standing posture, the lever 34 is held in the standing posture by the elastic force of the electrode connecting member 40, while when in the lying posture, the lever 34 is brought into the lying posture by the elastic force of the electrode connecting member 40. It is held (see FIG. 8). That is, the lever 34 forms a toggle by forming the contact surfaces 47 and 48. Therefore, the posture change of the electrode connecting member 40 is easy and reliable, and the lever 34 is prevented from standing up when the nurse or the like does not intend to remove the connector 14 from the moisture sensor 11. . Moreover, since the lever 34 includes the finger hook portion 49, a nurse or the like can operate the lever 34 more easily.

  Since the plurality of protrusions 72 are formed on the back surface 51 of the casing 33 of the connector 14, the air permeability of the back surface 51 of the casing 33 is improved. Since this connector 14 is attached to a patient undergoing an artificial dialysis treatment, the casing 33 may touch the human body during the artificial dialysis. In that case, by forming the protrusion 72, a gap is formed between the casing 33 and the human body, and air permeability is improved. Thereby, even if the casing 33 touches the human body for a long time, the skin is prevented from being rashed.

  As described above, since the corners of the casing 33 and the lever 34 are formed in a curved surface shape, there is an advantage that a smooth feeling can be obtained when the connector 14 is touched by a nurse or the like. Moreover, since the outer dimensions of the casing are set as described above, the connector 14 is not easily inserted into the mouth even if the patient has symptoms of dementia, for example, and the safety is high. In addition, since the piercing blade 45 provided on the arm 42 is spot-welded to the main body 44, the piercing blade 45 has an advantage that it is easily and reliably fixed to the main body 44 at a low cost.

  The other end 62 of the moisture sensor 11 is clamped by the clip 41. The switch 55 provided in the clip 41 is a normally closed type. Accordingly, the switch 55 is in an ON state before the moisture sensor 11 is held by the clip 41, and the switch 55 is turned OFF in a state where the moisture sensor 11 is held by the clip 41. Since the clip 41 only temporarily holds the moisture sensor 11 with a certain holding force, for example, if the patient pulls the moisture sensor 11 consciously or unconsciously, the moisture sensor 11 is removed from the clip 41. The switch is turned on. That is, a sign of a needle withdrawal accident is detected during artificial dialysis, and a needle withdrawal accident is prevented in advance.

  If the patient's arm bleeds due to an accident such as the needle dropping out during treatment, the blood is temporarily held by the breathable sheet 17 (see FIG. 3) of the moisture sensor 11. However, as shown in FIG. 3, when the bleeding becomes a certain amount or more, the blood wets the electrode sheet 15, and the electrodes 19 a and 19 b are electrically connected. As described above, the buzzer 12 is operated by the conduction between the electrodes 19a and 19b.

  In addition, when dialysis treatment is performed for a long time, the patient's arm may sweat and a large amount of sweat may occur depending on the patient's constitution. However, the patient's arm is disposed on the water-permeable sheet 17, the filter sheet 16 has the small holes 32, and the base sheet 18 constituting the electrode sheet 15 has air permeability. The sweat passes through the moisture sensor 11 as water vapor. Therefore, the sweat does not collect on the electrode sheet 15, and as a result, malfunction of the blood detection device 10 for artificial dialysis is prevented.

  In particular, since the base sheet 18 is mainly made of polyethylene and is mixed with calcium carbonate to achieve air permeability and waterproofness, the manufacturing cost of the electrode sheet 15 and thus the moisture sensor 11 is reduced. There is no significant increase.

4). Modification of the embodiment

  Next, a modified example of this embodiment will be described.

<First Modification>

  FIG. 14 is an exploded perspective view of the moisture sensor according to the first modification of the present embodiment. Also in the figure, the upper side of the figure is the side on which the liquid to be detected (that is, blood) comes into contact with the moisture sensor 90 being used.

  The moisture sensor 90 according to this modification differs from the moisture sensor 11 according to the above embodiment in that the moisture sensor 11 is a separate member different from the water-permeable sheet 17 and the upper base sheet 20 as shown in FIG. Whereas the filter sheet 16 is disposed between the water permeable sheet 17 and the overlay base sheet 20, in the moisture sensor 90 according to the present modification, as shown in FIG. The adhesive layer 91 is formed between the sheet 20 and the sheet 20. In other words, the adhesive layer 91 also serves as a filter sheet having the same function as the filter sheet 16. The other configuration of the moisture sensor 90 is the same as that of the moisture sensor 11.

  The adhesive layer 91 is typically made of a urethane resin. However, the adhesive layer 91 may be made of various other materials as long as the material has water repellency. By employing a urethane resin as the adhesive layer 91, the water-permeable sheet 17 and the overlay base sheet 20 are securely bonded. A large number of small holes 92 are provided in the adhesive layer 91. Since the urethane resin constituting the adhesive layer 91 has water repellency, the blood 92 permeated from the water-permeable sheet 17 side cannot immediately move to the overlay base sheet 20 side by providing the small holes 92. When a certain amount or more of blood exists, the blood moves through the small hole 92 to the overlay base sheet 20 side. The adhesive layer 91 is disposed so as to cover the entire effective area of the electrode sheet 15.

  The shape and size of the small holes 92 of the adhesive layer 91 are not particularly limited, but if the small holes 92 are too small, foreign substances and other objects are easily filled. For this reason, it is preferable that the internal diameter dimension of the small hole 92 is 1.0 mm or more. More preferably, it is 1.2 mm or more, More preferably, it is 1.5 mm or more. In addition, the large number of small holes 92 are usually distributed and arranged at equal intervals.

If the small holes 92 are too large, the probability of allowing moisture other than blood to pass through increases. For this reason, it is preferable that the internal diameter dimension of the small hole 92 is 4.0 mm or less. More preferably, the inner diameter of the small hole 92 is 3.5 mm or less, and further 3.0 mm or less. The interval between the adjacent small holes 92 is appropriately set with a standard of about 10 mm in the case of the small holes 92 having an inner diameter of 2.0 mm. If the density of the small holes 92 is too small, it is difficult for blood to pass through and detection is delayed. For this reason, it is preferable that the number of small holes 92 per 100 cm ² area of the adhesive layer 91 is set to about 50 or more and 500 or less.

  FIG. 15 is a diagram schematically showing an apparatus for forming the adhesive layer 91.

  As shown in the figure, the forming device 93 includes a transfer roller 94 and a pressing roller 95. The transfer roller 94 is rotated around the rotation shaft 96 by a predetermined driving device (not shown). The transfer roller 94 is made of metal or resin, and a large number of recesses 48 are provided on the peripheral surface 97 thereof. The pressing roller 95 is made of resin, rubber, or the like, and is disposed adjacent to the transfer roller 94 in the radial direction. The overlay base sheet 20 is fed between the transfer roller 94 and the pressure roller 95. The axial distance between the transfer roller 94 and the pressing roller 95 is set so that a predetermined gap is formed between them, whereby the overlay base sheet 20 passing between the transfer roller 94 and the pressing roller 95 is The pressure is pressed with a predetermined pressing force.

  The adhesive layer 91 (see FIG. 14) is formed by transferring urethane resin to the overlay base sheet 20. Specifically, urethane resin is applied to the peripheral surface 97 of the transfer roller 93. At this time, since the concave portion 98 is provided, the urethane resin is not applied to the portion of the peripheral surface 97 corresponding to the concave portion 98. When the transfer roller 94 is driven and the overlay base sheet 20 is fed between the transfer roller 94 and the pressure roller 95, the urethane resin applied to the peripheral surface of the transfer roller 94 is transferred to the overlay base sheet 20. The At this time, since the concave portion 98 is provided in the transfer roller 94, the urethane resin is not transferred to the portion corresponding to the concave portion 98 of the overlay base sheet 20, and the portion where the urethane resin is not transferred is the small hole. 92 is configured. In this way, the adhesive layer 91 having the small holes 92 is formed on the overlay base sheet 20. Of course, the adhesive layer 91 can be formed by other methods.

  In addition to the function of the filter sheet 16 according to the first embodiment, the adhesive layer 91 also has a function as an adhesive that bonds the water-permeable sheet 17 and the overlay base sheet 20 together. In other words, the adhesive that bonds the water-permeable sheet 17 and the overlay base sheet 20 has the function of the filter sheet 16. Therefore, it is not necessary to separately configure the filter sheet 16 as in the above-described embodiment, and as a result, the number of parts of the moisture sensor 90 is reduced, and there is an advantage that the manufacturing cost can be suppressed.

<Second Modification>

  Next, a second modification will be described.

  FIG. 16 is an exploded perspective view of a moisture sensor according to a second modification of the embodiment.

  The difference between the moisture sensor 100 according to the present modification and the moisture sensor 11 according to the embodiment is that the moisture sensor 100 includes a packaging bag body 101 that wraps the moisture sensor 11 according to the embodiment. . In addition, about another structure, it is the same as that of the moisture sensor 11 which concerns on the said embodiment. As shown in the figure, the packaging bag body 101 is formed in a sheet shape, and the moisture sensor 11 is wrapped inside by folding the bag body in half. Needless to say, the moisture sensor 100 includes the electrode sheet 15, the filter sheet 16, and the water-permeable sheet 17.

  FIG. 17 is a schematic diagram showing a cross-sectional structure of the packaging bag body 101.

  As shown in the figure, the packaging bag body 101 has a three-layer structure, and includes a base 102, a breathable waterproof sheet 103 disposed on the base 102, and a nonwoven fabric 104 disposed thereon. Have. The base 102, the breathable waterproof sheet 103, and the nonwoven fabric 104 are integrated by adhesion or the like. In the figure, the upper side surface is a surface in contact with the moisture sensor 11 and constitutes the inner surface of the packaging bag 101.

  The base 102 is made of Japanese paper in this embodiment. Of course, any other material may be employed as long as it has air permeability. The breathable waterproof sheet 103 is mainly composed of sheet-like polyethylene, and is mixed with calcium carbonate. By mixing the calcium carbonate particles, a large number of fine holes 105 are formed through the sheet-like polyethylene. The diameter of the fine hole 105 is set to about 1 μm to 100 μm. Moreover, the said nonwoven fabric 104 is comprised when a pulp fiber entangles irregularly, and has sufficient air permeability and water retention.

  Therefore, gas can pass through the base 102, the breathable waterproof sheet 103 and the nonwoven fabric 104, but water drops cannot pass through. The thickness dimension of the breathable waterproof sheet 103 is not particularly limited. As a material constituting the breathable waterproof sheet 103, a resin film such as polyester, polypropylene, or polyvinyl chloride can be used instead of the polyethylene. By adopting these materials, the breathable waterproof sheet 103 can have a certain mechanical strength and also a flexibility.

  As described above, the packaging bag body 101 is folded in half so as to wrap the moisture sensor 11. As shown in FIG. 16, in this embodiment, the peripheral edges 105 to 108 are bonded in a state where the packaging bag body 101 is folded in half. Examples of the bonding means include an adhesive, but various other bonding means can be adopted. Thus, the water | moisture content sensor 11 is sealed by the packaging bag 101 by the periphery 106-108 of the packaging bag 101 being adhere | attached.

  Since the packaging bag body 101 has air permeability as described above, the moisture sensor 11 can be sterilized while being wrapped in the packaging bag body 101. This is because the packaging bag body 101 has air permeability. Specifically, when the sterilizing gas is supplied from the outside of the packaging bag body 101, the sterilizing gas passes through the packaging bag body 101 and enters the inside thereof. Thereby, a sterilization effect can be exerted on the moisture sensor 11. Thus, in this embodiment, since the moisture sensor 11 is packaged by the packaging bag body 101 having air permeability, the moisture sensor 11 is sterilized while being sealed and packaged in the packaging bag body 101. Applied. Thereby, there exists an advantage that the manufacturing cost of the moisture sensor 100 as a sterilized product is reduced.

  Further, since the moisture sensor 100 includes the packaging bag body 101, the packaging bag body 101 functions as a napkin when the moisture sensor 100 is used, that is, when the artificial dialysis treatment is started. . FIG. 18 is a diagram illustrating the usage points of the packaging bag body 101 in the order of (a) to (c).

  As shown in FIG. 5A, when the artificial dialysis treatment is started, the moisture sensor 11 wrapped in the packaging bag 101 is placed on a bed, for example. As shown in FIG. 2B, the packaging bag body 101 is opened from, for example, the corner 109 thereof. And as the figure (c) shows, in the state opened completely, the said nonwoven fabric 104 is exposed to an upper surface. At this time, the moisture sensor 11 is once taken out from the packaging bag body 101.

  The patient places his arm as it is on the nonwoven fabric 104 of the opened packaging bag 101. An artificial dialysis needle is inserted into the patient's arm. At this time, blood may leak from the patient's arm. Even if blood leaks at this time, the non-woven fabric 104 can absorb this, and further, since the breathable waterproof sheet 103 is disposed, the blood leaks out from the packaging bag body 101. There is nothing. This prevents the bed from getting dirty or the moisture sensor 11 from being damaged by the blood leaked when the artificial dialysis needle is pierced by the patient's arm.

  In this embodiment, since the peripheral edges 106 to 108 of the packaging bag body 101 are merely bonded so as to wrap the moisture sensor 11 inside, the packaging bags are separated by being separated from the peripheral edges 106 to 108. The body 101 is easily deployed. Therefore, there is an advantage that the packaging bag body 101 can be easily and quickly opened when the artificial dialysis treatment is started.

  In this embodiment, the moisture sensor 11 according to the above embodiment is wrapped in the packaging bag body 101. However, instead of this, the moisture sensor 90 according to the first modification may be wrapped. Of course.

DESCRIPTION OF SYMBOLS 10 ... Blood detector for artificial dialysis 11 ... Water sensor 13 ... Alarm 14 ... Connector 15 ... Electrode sheet 16 ... Filter sheet 17 ... Water-permeable sheet 18 ... Base sheet 19 ... Electrode 20 ... Overlay base sheet 21 ... Underlay base sheet 22 ... Reinforcement sheet 23 ... Upper sheet 24 ... Lower sheet 25 ... Base cloth 26 ... Non-woven fabric 27 ... Fine pore 28 ... Water-soluble adhesive 30 ... Electrode terminal 31 ... Electrical resistance element 32 ... Small hole 33 ... Casing 34 ... Lever 40 ... Electrode connection Member 41 ... Clip 45 ... Puncture blade 55 ... Switch 61 ... One end 62 ... Other end 90 ... Moisture sensor 91 ... Adhesive layer 92 ... Small hole 100 ..Moisture sensor 101 · Packaging bag 102 ... base 103 ... waterproof breathable sheet 104 ... nonwoven 105 ... micropores 106-108 ... peripheral

Claims (4)

A moisture sensor for detecting the presence of blood by exhibiting insulation in a dry state and conductivity in a state containing moisture, an alarm device for informing that at least the moisture sensor has detected the presence of blood, and A blood detection device for artificial dialysis having a notification device and a connector for connecting the moisture sensor,
The moisture sensor
A base sheet having air permeability and an electrode sheet having a pair of electrodes arranged on the base sheet;
A water-repellent filter sheet superimposed on the electrode sheet and provided with a large number of small holes;
A water-permeable sheet with a certain water retention property superimposed on the filter sheet,
The above connector
A casing,
A conductive electrode connecting member provided on the casing and disposed so as to span between the pair of electrodes by sandwiching one end of the moisture sensor;
A clip that is provided in the casing and that can hold the other end of the moisture sensor with a constant holding force;
The conductive electrode connecting member includes a piercing blade that pierces the electrode sheet,
The blood detection device for artificial dialysis, wherein the clip includes a normally closed switch that is turned off when the moisture sensor is sandwiched.   The blood detection apparatus for artificial dialysis according to claim 1, wherein the base sheet is provided with a polyethylene film in which a large number of fine works that exhibit air permeability and waterproofness are formed by being mixed with calcium carbonate.   The blood detection apparatus for artificial dialysis according to claim 1 or 2, wherein an adhesive layer that bonds the electrode sheet and the water-permeable sheet also serves as the filter sheet. The normally closed switch
The clip has a pair of electrode plates arranged along the direction of sandwiching the moisture sensor,
One electrode plate is elastically biased to contact the other electrode plate,
The contact release bar for separating the one electrode plate from the other electrode plate when the clip is pressed by the moisture sensor while holding the moisture sensor is provided. The blood detection device for artificial dialysis according to any one of the above.

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