JP5864884B2 - Measuring apparatus and measuring method - Google Patents

Description

  The present invention relates to a measuring apparatus and a measuring method for measuring biological information such as body temperature.

  Patent Document 1 describes a body temperature information terminal device and a body temperature information processing system that can easily measure basal body temperature and the like. The body temperature information terminal device described in Patent Document 1 has a body surface temperature detection unit attached to the front side of the casing and a clip attached to the back side. The body surface temperature detection unit is connected to the control unit of the circuit board accommodated in the casing, and this control unit is connected to the connection unit. And a user pinches | interposes a body temperature information terminal device between an abdomen and underwear in the state which made the body surface temperature detection part contact the abdomen before bedtime, and fixes it with a clip. As a result, the body temperature information terminal device measures and stores the body temperature at regular intervals from the start time to the end time while sleeping.

  Patent Document 2 describes an electronic thermometer that can confirm the contact state of a human body with a simple and easy-to-assemble configuration. The electronic thermometer of patent document 2 has a probe part which equips a tip with the temperature measuring part applied to a user's to-be-measured site | part. The electronic thermometer further includes an inner hollow outer case in which a temperature sensor for detecting temperature is arranged in the temperature measuring unit, and an electronic circuit board on which a control circuit for processing data detected by the temperature sensor is formed. And an inner case attached to the hollow interior of the outer case, and a pair of electrodes fixed to the inner case and positioned inside the probe portion when the inner case is attached to the outer case. The control circuit measures the capacitance between the pair of electrodes, and determines whether or not the probe unit is appropriately in contact with the measurement site of the user based on the change in the measured capacitance. A determination unit is provided.

JP 2004-163391 A JP 2010-32324 A

  The body temperature is typical information indicating the state of a living body such as a human being, a pet, and a domestic animal, and is obtained mainly by measuring the temperature of the surface (skin) of the living body. Similarly, information obtained from the surface of a living body includes bioimpedance, skin surface humidity, and the like. In order to acquire such biological information with high accuracy, the part for sensing biological information needs to be in close contact with the body surface. For example, in the body temperature information terminal device of Cited Document 1, the body surface temperature detection unit protrudes from the casing, and the body surface temperature detection unit is pressed against the abdomen with a clip on the back side of the casing to fix the body surface temperature. The detection unit is in close contact with the abdomen. Moreover, in the electronic thermometer of the cited reference 2, the probe part closely_contact | adhered to the body surface is carried out by pinching and measuring the probe part which equips the tip with a temperature measuring part.

  If the protrusion is pressed against the body, the user may feel uncomfortable or uncomfortable when measuring. In addition, a measurement method in which the probe is sandwiched between the armpits may impede freedom of user's behavior during measurement. Therefore, there is a demand for an apparatus that measures biological information such as body temperature, and that is less likely to cause discomfort and discomfort, and that does not easily impede freedom of action and has higher accuracy.

  One embodiment of the present invention is an apparatus for measuring biological information. This device acquires first information indicating a state of a surface of a living body via a case that includes a flat surface or a gently curved first surface that contacts the living body and a first region of the first surface. The 2nd sensor which acquires the 2nd information including the contact state of the surface of a living body and the 2nd field via the 1st sensor and the 2nd field surrounding the 1st field of the 1st surface And have.

  The device has a first surface that measures a state of the surface of a living body on a first surface that is a plane or a gently curved common surface or a single surface, and a second region that surrounds the first region. A second region for determining a contact state between the surface of the living body and the second region is provided. Therefore, if the second area is in close contact with the surface of the living body, the first area surrounded by the second area is in close contact with the surface of the living body. You may think that For this reason, the first information obtained in the first region can be obtained by judging the degree of adhesion of the second region based on the second information without directly judging the degree of adhesion of the first region. It can be determined whether or not the information is information when the first region is in close contact with the living body.

  As described above, in this device, the first information is obtained by the second information obtained through the second region provided on the same surface (a flat surface or a gently curved surface (first surface)) as the first region. The degree of adhesion of the area can be determined. For this reason, it is not necessary to press the part against the living body or to sandwich the part under the arm with a strong force in order to secure the degree of adhesion of the part (part) for sensing the biological information. Conversely, it is only necessary to bring a relatively wide surface including the second region into contact with the surface of the living body so that the second information indicates a contact state. Therefore, with this device, biological information such as body temperature can be obtained accurately and with little discomfort or discomfort to the user (measured person) and with little obstruction of freedom of action during measurement. You can get it.

  Thus, in this apparatus, in order to press the sensor against the body, there is no need to provide a portion protruding from the case or a probe protruding from the tip. Therefore, the case can be designed in a thin box shape or plate shape in which at least one outer surface is flat or gently curved, and the first surface can be set to at least a part of one outer surface of the case. For this reason, it becomes possible to provide a device that can be applied to the surface of a living body like a bandage to accurately acquire biological information, and it is relatively easy to wear for a long time. It is possible to provide a device that is difficult to become.

  This apparatus may transmit the first information and the second information to an external host system such as a personal computer by wire or wireless. The apparatus may also include a control unit that processes the first information obtained by the first sensor and / or the second information obtained by the second sensor. In addition, a typical second sensor includes a plurality of electrodes arranged to face the second region and surround the first region. The control unit preferably has a function of acquiring capacitance and / or DC impedance between the plurality of electrodes as the second information. The state of contact between the second region and the living body can be grasped from the capacitance and the direct current impedance.

  The plurality of electrodes preferably include an annular first electrode arranged so as to surround the first region and an annular second electrode arranged so as to surround the first electrode. Since the periphery of the first region can be continuously covered by the annular first and second electrodes, the reliability of determination as to whether or not the first region is in contact with the living body can be further improved.

  The control unit may have a function of processing the first information and the second information in association with each other. The function to process in association is to output the first information as valid information to an external device in a wired or wireless manner when the second information is determined to be in contact with the living body by the second information, Or when the second information determines that the second area is not in contact with the living body based on the second information, an alarm is output by an appropriate method, the measurement of the first information is stopped, It may include a function of stopping power consumption of the unit and / or the first sensor related to measurement of one information.

  What becomes a problem when acquiring information on the surface of the living body located at the boundary between the outside world and the living body by the sensor (first sensor) is the influence of the outside world on the first sensor. For example, when the first sensor is a temperature sensor that obtains the surface temperature of a living body, if the first sensor is exposed to the outside world, it is affected by the temperature (outside temperature or room temperature). In this apparatus, the first sensor is provided to face the first region of the first surface, and the side opposite to the first surface (back side) of the first sensor is placed on the first surface. A heat insulating material is provided so as to cover the opposite side of the first region, and the influence of the temperature on the first region as well as the first sensor can be suppressed. The heat insulating material may be arranged including the opposite side (back side) of at least a part of the second region of the first surface, and the surface temperature of the living body can be measured with higher accuracy by the first sensor.

The device includes a third sensor that measures the temperature of the second surface of the case that does not contact the living body, and a first sensor that is disposed between the first region of the first surface and the second surface. And a third sensor for measuring the outer surface temperature of the case when heat obtained from the first region of the first surface is released from the second surface via the first member. It is . The body depth temperature can be calculated from the body surface temperature, the case outer surface temperature, the heat conduction coefficient of the first member, and the assumed heat conduction coefficient in the body. An example of the calculation formula is the following formula (1).

Tc = (Ta−Tb) × (K / J) + Ta (1)
Here, Ta is the body surface temperature, Tb is the case outer surface temperature, Tc is the temperature in the deep part of the body, J is the thermal conductivity coefficient of the first member, and K is the standard thermal conductivity coefficient of the human body. In this specification, the thermal conductivity coefficient is a coefficient obtained by dividing the thermal conductivity by the length, and is a coefficient excluding the length factor.

  Further, the function of calculating the temperature of the deep part of the body may include a function of correcting the assumed heat conduction coefficient in the body based on the capacitance or DC impedance obtained as the second information. The second information for determining the presence or absence of adhesion in the first region is also one of the biological information obtained from the surface of the living body, and by correcting the heat conduction coefficient in the body by the second information, further accuracy can be obtained. High body depth temperature is obtained.

  Another aspect of the present invention is a method for measuring biological information using an apparatus that is at least partially in contact with a living body. The apparatus acquires first information indicating a state of a surface of a living body via a flat surface or a gently curved first surface that contacts the living body and a first region of the first surface. A second sensor for acquiring second information including a contact state between the surface of the living body and the second region via the sensor and a second region surrounding the first region of the first surface; A control unit for processing first information obtained by one sensor and / or second information obtained by a second sensor. The method for measuring the biological information includes processing the first information and the second information in association with each other.

  Processing in association with each other may include outputting the first information when it is determined by the second information that the second region is in contact with the living body. Limited to the effective first information, it can be output to an external device by wire or wirelessly. The processing in association is an appropriate method when the first and / or second information is recorded in the internal memory of the device, or when the second information determines that the second area is not in contact with the living body. May output an alarm, stop the measurement of the first information, or stop the power consumption of the unit and / or the first sensor related to the measurement of the first information.

Further, according to this method, the outer surface temperature of the case when the control unit releases the heat obtained from the first region of the first surface from the second surface via the first member by the third sensor. and measuring, body surface temperature, casing external surface temperature, further organic and calculating the first heat transfer coefficient, and assumed the temperature of the body deep by thermal conduction coefficient of the body member. Calculating the temperature of the deep part of the body may include correcting the heat conduction coefficient in the body assumed by the second information.

Sectional drawing which shows schematic structure of a thermometer. The bottom view which shows a mode that the thermometer was seen from the lower side. The thermometer block diagram. The schematic diagram which shows the conduction state of heat. The flowchart which shows the control method of a thermometer. Another example showing the arrangement of electrodes.

  FIG. 1 shows a schematic configuration of a device (thermometer) for measuring a human body temperature as biological information using a cross section. FIG. 2 shows the thermometer 1 viewed from the side in contact with a person (hereinafter, the lower side). The thermometer 1 includes a thin box-shaped case 2 and sensors 5, 7 and 8 housed inside the case 2. Furthermore, the thermometer 1 includes a control unit 10 that performs various processes related to the thermometer 1, a display (for example, LCD) 14 that displays processing results, and a battery that is connected to the control unit 10 via a wiring 19. 13, and these are also housed in the case 2.

  The case 2 is a thin rectangular parallelepiped or a plate, and includes upper and lower surfaces (outer surfaces) 2a and 2b that are relatively wide and a side surface 2c that forms the periphery of the upper and lower outer surfaces 2a and 2b. One outer surface 2a (the first surface, hereinafter referred to as the lower surface 2a) of the case 2 is substantially flat, and a first region 21 for detecting body temperature is provided at the center as indicated by a virtual line (dashed line). A second region 22 for sensing contact with the surface 15s of the human body 15 is provided so as to surround the outside of the first region 21 (see FIG. 2). The line indicating the boundary between the first region 21 and the second region 22 is a virtual line and may not appear on the outer surface 2a. A line indicating the boundary between the first region 21 and the second region 22 may be indicated on the lower surface 2a of the case 2 by an appropriate method in order to show the body temperature measurement region or the like to the user. The lower surface 2a of the case 2 may be a surface that is gently curved so that the first region 21 protrudes downward.

  The thermometer 1 has a case 2 having a length and width (length width of the lower surface 2a) of about several millimeters to several centimeters and a thickness of about several millimeters to several centimeters. Therefore, the lower surface 2a can be made sticky, or can be fixed (applied) to an appropriate position on the human body 15 using an adhesive tape 3 such as a bandage as shown by a one-dot chain line in FIG. You may attach so that the lower surface 2a of the thermometer 1 may closely_contact | adhere to the surface 15s of the human body 15 by other methods, such as a belt and a bandage.

  The case 2 of the thermometer 1 is entirely formed of a suitable resin, for example, a nonconductive resin such as an ABS resin or an elastomer. Therefore, a sensor attached to the inner surface 28a of the lower wall 29a or embedded in the lower wall 29a by bringing the lower surface 2a, which is the outer surface of the lower wall 29a of the case 2, into close contact with the surface 15s of the human body 15. From 5 and 7, information (biological information) of the human body 15 can be acquired. Specifically, a temperature sensor (thermistor in this example) 7 is attached to the inner surface 28a of the lower wall 29a of the case 2 so as to face (confront) a part of the first region 21 of the lower surface 2a. The first information on the surface 15 s of the human body 15, in this example, the body surface temperature Ta is obtained via the first region 21. The temperature sensor 7 is connected to the control unit 10 by a wiring 17.

  In addition, on the inner surface 28a of the lower wall 29a of the case 2, annular electrodes 6a and 6b are provided on the second sensor 5 so as to face (confront) the second region 22 surrounding the first region 21 of the lower surface 2a. It is attached as. The second sensor 5 has a function as a contact sensor or a contact sensor, and includes second information including information indicating a contact state between the surface 15 s of the human body 15 and the second region 22 via the second region 22. Information, in this example, the capacitance SC between the electrodes 6a and 6b is obtained.

  As 2nd information including the information which shows a contact state, it is also possible to measure the direct current impedance (electrical resistance, body surface resistance) between them using the electrodes 6a and 6b. In this case, however, the electrodes 6a and 6b need to be directly applied to the body surface 15s, and the electrodes 6a and 6b need to be disposed so as to be exposed on the lower surface 2a. In this case, as the electrodes 6a and 6b, stainless steel electrodes, gold plating, and the like can be adopted, but it is necessary to cope with waterproofing and metal allergy.

  In the thermometer 1 of this example, as the electrodes 6a and 6b, an electrode made of a general material such as copper or aluminum can be adopted, and by acquiring the capacitance SC through the lower wall 29a, Problems such as waterproofing and metal allergies can be prevented. These electrodes 6a and 6b for measuring the capacitance SC may be embedded when the case 2 is molded so as to be integrated with the lower wall 29a, and are disposed on the lower surface 2a of the lower wall 29a to form a thin electric insulating film. The electrodes 6a and 6b may be covered. The second information acquired by the second sensor 5, that is, the capacitance SC or the direct current impedance is information indicating a contact state, and information on the human body (biological information), for example, body fat percentage, It can also be used as information indicating the thermal conductivity coefficient. The second sensor 5 may be provided so as to acquire both the capacitance SC and the DC impedance as the second information.

  The thermometer 1 is provided with a first region 21 for measuring the body surface temperature Ta on a single lower surface 2a that is flat or gently curved, and is in contact with the body surface so as to surround the first region 21. In this example, a second area 22 for obtaining the capacitance SC is provided. Therefore, if the second region 22 is in close contact with the human body surface 15s due to the value of the capacitance SC or the variation of the capacitance SC, it is a region of the lower surface 2a that is a common surface with the second region 22. The first region 21 surrounded by the second region 22 is considered to be in close contact with the human body surface (body surface) 15s. For this reason, the body surface temperature Ta measured through the first region 21 by the capacitance SC is equal to the surface of the human body 21 without directly determining the degree of adhesion of the first region 21. It can be determined whether or not the temperature is in close contact with 15s.

  Therefore, it is not necessary to press the first region 21 of the thermometer 1 against the human body 15 with a strong force or to sandwich the thermometer 1 under the armpit, and the relatively wide lower surface 2a including the second region 22 is formed on the human body surface 15a. The body surface temperature Ta can be measured with high accuracy simply by contacting or in close contact with the substrate so that the value of the capacitance SC obtained in the second region 22 indicates the contact state. For this reason, the thermometer 1 can acquire the body temperature with high accuracy in a state in which the user (measured person) is less likely to feel uncomfortable or uncomfortable, and the freedom of behavior during measurement is less likely to be disturbed.

  The thermometer 1 further includes a temperature sensor 8 that measures the outside air temperature. The temperature sensor 8 of this example is a thermistor, and is installed in the case 2 so as to be exposed to the upper surface 2b of the case 2 or to detect the outside air temperature through the upper wall 29b constituting the upper surface 2b of the case 2. Yes. The temperature sensor 8 is connected to the control unit 10 by a wiring 18. The lower side (back side) of the temperature sensor 8 is connected to the first region 21 via the first member 9 having a known thermal conductivity. For this reason, the temperature (case outer surface temperature) Tb, in which heat from the body surface is transmitted through the first member 9 by the temperature sensor 8 and is radiated from the upper surface 2b of the case 2, can be measured. Therefore, the body temperature Tc can be calculated by interpolating the body surface temperature Ta using the case outer surface temperature Tb as the pseudo body surface temperature.

  When the thermal conductivity of muscle is about 0.4 (W / m / K) and the thermal conductivity of fat is about 0.2 (W / m / K), polyethylene (0 .41), a resin such as an epoxy resin (0.21) can be used as the first member 9.

  The thermometer 1 further includes a heat insulating material 25 disposed inside the case 2 so as to cover the inside (upper side, opposite to the lower surface 2a) of the temperature sensor 7 that measures the body surface temperature Ta. The heat insulating material 25 covers not only the back side of the temperature sensor 7 but also at least the opposite side of the first region 21 so as to surround the temperature sensor 7, and is disposed so as to cover a part of the second region 22. . Furthermore, the heat insulating material 25 covers the periphery of the first member 9 and is provided so as to cover the inside (the lower side, the side opposite to the upper surface 2b) of the temperature sensor 8 that measures the case outer surface temperature Tb.

  By covering the inside of the temperature sensor 7 and the inside of the first region 21 with the heat insulating material 25, that is, the side opposite to the body surface 15s, the outside of the temperature sensor 7 (part excluding the body surface 15s, for example, outside air and Heat transfer (heat radiation) to the inside of the case 2 can be suppressed, and heat transfer from the portion of the first region 21 of the lower wall 29a to the outside can be suppressed. Therefore, the body surface temperature Ta can be accurately measured even in a system in which the temperature sensor is sandwiched between the armpits to suppress heat dissipation from the temperature sensor, and a system in which the lower surface 2a is in close contact with the body surface 15s. Furthermore, in this thermometer 1, the sensor 5 provided in the second region 22 outside the first region 21 is the thin electrodes 6a and 6b, and the heat insulating material 25 is provided so as to cover these electrodes 6a and 6b. It is possible to arrange. Therefore, it is possible to arrange the heat insulating material 25 in a wider range covering the first region 21, and the body surface temperature Ta can be measured with higher accuracy by the temperature sensor 7.

  Further, the first member 9 is covered with the heat insulating material 25, and the temperature sensor 8 for measuring the case outer surface temperature Tb is covered except for the side facing the case outer surface 2b. The temperature Tb when the obtained heat is transmitted through the first member 9 and is radiated from the outer surface 2b of the case 2 can be measured with higher accuracy.

  The outer surface 2b of the case 2 is further provided with a display 14 for displaying the measured body surface temperature Ta and the like, and a lid 13a for replacing the battery 13 as a main power source. Therefore, the thermometer 1 can be freely moved by the user while attached to the human body (body) 15. Furthermore, it is not necessary to put the thermometer 1 under the armpit, and it is only necessary to keep the thermometer 1 in close contact with any surface 15s of the body 15, so that freedom of action is inhibited or sleep is inhibited. Less is. The measurement result can be confirmed on the display 14, stored in a memory, or wirelessly transmitted to an external device as described below.

  In FIG. 3, the outline | summary of the function of the thermometer 1 is shown with the block diagram. The thermometer 1 includes a control unit 10 including a circuit element 11 such as a CPU 110 and a memory 140 and a board (circuit board) 12 on which the circuit elements 11 are mounted, and various functions are provided by the control unit 10. The control unit 10 includes a temperature measurement circuit 120 that acquires temperature (data indicating temperature) by the temperature sensors 7 and 8, and a capacitance measurement circuit that measures the capacitance SC between the electrodes 6a and 6b in the second region 22. 130, a wireless communication circuit 150, a memory 140 that stores data and programs, and a CPU 110 that controls these circuits and realizes some functions by downloading programs from the memory 140. The CPU 110 has a function (data input / output function, data input / output unit) 111 for performing data input / output (indicated by a solid line) with the temperature measurement circuit 120, the capacity measurement circuit 130, the wireless communication circuit 150, and the memory 140; And a function (on / off control function, on / off control unit) 112 for controlling (on / off control, indicated by a broken line) the temperature measuring circuit 120, the capacity measuring circuit 130, and the wireless communication circuit 150.

  The capacitance measurement circuit 130 includes an oscillation circuit (OSC) 131 that supplies AC power to one of the electrodes 6a and 6b in the second region 22 via the resistor R, and a phase detection circuit that detects a phase difference before and after the resistor R. 133, and an A / D converter 135 that captures a phase difference (phase delay) as a voltage signal, converts the voltage signal into a digital signal, and supplies the digital signal to the CPU 110. In this example, power is supplied to the inner electrode 6a, and the outer electrode 6b is grounded.

  The AC voltage (AC signal, 10 MHz in this example) supplied from the oscillation circuit (OSC) 131 passes through the resistor R and enters the electrode 6a. The electrodes 6a and 6b form a capacitor C, and the electrode 6b is connected to the ground. Accordingly, the phase of the AC voltage is delayed by the resistor R and the capacitor C with respect to the current, and this phase delay increases as the capacitance of the capacitor C increases. Since the dielectric constant of the body surface 15s is much higher than that of air, the capacitance of the capacitor C when the electrodes 6a and 6b are in contact with the body surface 15s increases, and the delay of the AC signal also increases. Therefore, by digitizing the phase delay amount φd by the A / D converter 135 and supplying the digitized amount to the CPU 110, the CPU 110 can determine the capacitance SC between the electrodes 6a and 6b based on the phase delay amount φd.

  The control unit 10 includes a capacitance measuring circuit 130 that acquires a phase delay amount φd as second information including information indicating a contact state between the body surface 15s and the second region 22. In addition, the CPU 110 turns on the circuit elements 131, 133, and 135 of the capacitance measuring circuit 130 at a predetermined timing by the on / off control function 112, and the static signal between the electrodes 6a and 6b by the delay amount φd obtained from the capacitance measuring circuit 130. It includes a function (contact determination function, contact determination unit) 115 that determines the capacitance SC and determines that the second region 22 is in contact (contact) with the body surface 15s when the delay amount φd is large.

  CPU 110 further includes several functions for processing information (second information) obtained by contact determination function 115 and measurement of body surface temperature Ta in association with each other. One function is that when the contact determination function 115 determines that the second region 22 is in contact with the body surface 15s, the temperature measurement circuit 120 is turned on by the on / off control function 112, and the body surface temperature is detected by the temperature sensors 7 and 8. A first temperature acquisition function (first temperature acquisition unit) 116 that acquires Ta and case outer surface temperature Tb. This function 116 can also be set to measure only the body surface temperature Ta. Function 116 further includes a function of recording body surface temperature Ta and / or case outer surface temperature Tb in memory 140 in the order of measurement, and recording with measurement time and / or delay amount φd.

  The first temperature acquisition function 116 further measures the body surface temperature Ta and / or the case outer surface temperature Tb, and turns on the wireless communication circuit 150 by the on / off control function 112, and the measured body surface temperature Ta and / or A function of outputting the case outer surface temperature Tb to an external device such as a personal computer as a host may be included. The wireless communication circuit 150 is connected to the Internet via a public wireless LAN or public telephone network, and includes a function of storing the measured body surface temperature Ta and / or case outer surface temperature Tb in a predetermined server prepared on the Internet. May be.

  The first temperature acquisition function 116 uses the temperature measurement circuit 120 only when the contact determination function 115 determines that the first region 21 is in contact with the body surface 15s through the determination of the second region 22. The temperature is turned on to measure the temperature, and the wireless communication circuit 150 is turned on to transmit / receive data. Therefore, when the first region 21 of the thermometer 1 is not in contact with the body surface 15s, power consumption required for temperature measurement and wireless communication can be reduced, and consumption of the battery 13 can be suppressed. For example, temperature measurement and wireless communication can be automatically stopped when the thermometer 1 is removed from the human body 15. In addition, when wireless communication is stopped, it is possible to automatically detect from the outside that a situation has occurred in the user that causes the thermometer 1 to be disconnected during the measurement. For this reason, the thermometer 1 can not only remotely monitor the user's body temperature but also monitor (sense) any abnormal situation in the user.

  One of the other functions for processing the measurement of the delay amount φd (second information) obtained by the contact determination function 115 and the body surface temperature Ta (first information) is the second temperature acquisition function. (Second temperature acquisition unit) 117. This function 117 periodically turns on the temperature measuring circuit 120 by the on / off control function 112 together with or after the delay amount φd, and acquires the body surface temperature Ta and the case outer surface temperature Tb by the temperature sensors 7 and 8, respectively. This function 117 can be set to measure only the body surface temperature Ta. This function 117 further includes a function of recording the measured body surface temperature Ta and / or case outer surface temperature Tb together with or in association with the delay amount φd. By recording the measured body surface temperature Ta and / or case outer surface temperature Tb together with the delay amount φd indicating the degree of contact, it is possible to determine later whether or not appropriate temperature measurement has been performed. The function 117 may include a function of turning on the wireless communication circuit 150 and transmitting the measured body surface temperature Ta and / or case outer surface temperature Tb to an external device together with the delay amount φd.

  Further, when CPU 110 determines that second region 22 of thermometer 1 is not in contact with body surface 15s based on delay amount φd (second information) obtained by contact determination function 115, CPU 110 outputs an abnormality. (Alarm function, alarm unit) 118 is included. The alarm function 118 turns on the wireless communication circuit 150 to notify an abnormality to the outside, displays an alarm on the display 14 of the thermometer 1, flashes an abnormality display LED provided separately on the thermometer 1, A function to sound a buzzer may be included. Further, the alarm function 118 may include a function of notifying an abnormality by the above method when the temperature Ta and / or Tb acquired by the temperature acquisition unit 116 and / or 117 exceeds a predetermined temperature range. . In addition, the alarm function 118 is an appropriate method that, after the body temperature measurement is started, the rapid change in the temperature Ta and / or Tb acquired by the temperature acquisition unit 116 and / or 117 is terminated and the steady measurement is started. May include a function of contacting the user or the outside.

CPU 110 further includes a function 119 for calculating body depth temperature Tc from body surface temperature Ta and case outer surface temperature Tb acquired by temperature acquisition unit 116 and / or 117. This function 119 is obtained from the Fourier law by using the body surface temperature Ta, the case outer surface temperature Tb, the thermal conductivity coefficient K near the surface of the human body 15, and the thermal conductivity coefficient J of the first member 9. The temperature Tc at the deep part of the body is calculated by the following formula. The thermal conductivity coefficients K and J are the respective thermal conductivities divided by the length.
Tc = (Ta−Tb) × (K / J) + Ta (1)

  As described above, the thermal conductivity in the vicinity of the surface of the human body 15 is assumed to be 0.2 to 0.4 (W / m / K), and the first member 9 having an appropriate thermal conductivity and length. By adopting, the ratio K / J of the heat conduction coefficient can be set to an appropriate value L of around 1. The thermal conductivity coefficient J of the first member 9 may be about 1 to 8 times the thermal conductivity coefficient K of the human body.

  The function 119 for calculating the temperature of the deep part of the body further estimates the amount (thickness) of the body fat of the user's body 15 from the delay amount φd obtained by the contact determination function 115, and the proportional constant L of the equation (1). Includes the ability to change The delay amount φd indicates the capacitance of the body 15, and the capacitance of the body 15 is also one of biological information of the body 15, and is a value related to the body fat percentage or fat thickness. For example, if it is determined that the body fat percentage is high based on the delay amount φd, the thermal conductivity of fat is lower, so the proportionality constant L is increased 0.95 times. If it is determined that the body fat percentage is low based on the delay amount φd, the proportionality constant L is increased by 1.05 times. With this function, the temperature Tc at the deep part of the body can be calculated with higher accuracy.

  For example, when the outside air temperature is lower than the body temperature Tc, the body temperature Tc is higher than the body surface temperature Ta, and when the outside air temperature is higher than the body temperature Tc, the body surface temperature Ta is higher than the body temperature Tc. Get higher. Therefore, the temperature Tc in the deep part of the body cannot be calculated simply by measuring the body surface temperature Ta. However, the temperature Tc at the deep part of the body can be measured by measuring the temperature via the covering material (first member) 9 having a specific heat conduction coefficient J outside the sensor 7 for measuring the temperature of the body surface. The first member 9 may be air.

  That is, as shown in FIG. 4, the amount of heat 221 in the deep part of the body 15 reaches the body surface 15 s via fat, epidermis, etc. 222 near the surface of the living body. If there is another first member 9 here, the heat 223 is transmitted through the first member 9 and is radiated to the outside air outside. The temperature Tb at which the heat is radiated is measured, and the temperature Tc at the deep part of the body can be calculated from the relationship with the body surface temperature Ta.

  Further, the function 119 for calculating the temperature Tc of the deep body can determine the temperature Tc of the deep body even in a state where a thin shirt or the like is interposed. Since the capacitance between the electrodes changes when the shirt is sandwiched between the thermometer 1 and the human body 15, by using the data measured in advance, the thermal conductivity coefficient in that state is obtained. The temperature Tc can be estimated.

  FIG. 5 is a flowchart showing an example of a method for obtaining the body surface temperature Ta and the deep body temperature Tc by the thermometer 1. In step 51, when it is time to measure the temperature (body temperature) with the thermometer 1, in step 52, the contact determination function 115 turns on the capacitance measuring circuit 130 and sets the delay amount φd indicating the capacitance SC of the electrodes 6a and 6b. get. In step 53, the contact determination function 115 determines whether or not the second region 22 of the thermometer 1 is in contact (contact) with the body surface 15s based on the delay amount φd. The alarm function 118 outputs an alarm using the wireless communication circuit 150 or the like.

  On the other hand, when the second region 22 is in contact with the body surface 15s, it is determined that the first region 21 is in contact with the body surface 15s, and in step 54, the first temperature acquisition function 116 detects the temperature. The measurement circuit 120 and the wireless communication circuit 150 are turned on. The first temperature acquisition function 116 acquires the body surface temperature Ta and the case outer surface temperature Tb from the temperature sensors 7 and 8. Further, in step 55, the function 119 for calculating the temperature Tc of the deep body part calculates the temperature Tc of the deep body part according to the equation (1) using the body surface temperature Ta and the case outer surface temperature Tb. At this time, the thermal conductivity coefficient may be corrected to an appropriate value using the delay amount φd obtained by the capacitance measuring circuit 130.

  Further, in step 56, the first temperature acquisition function 116 stores data such as the measured body surface temperature Ta, the body depth Tc, the delay amount φd, and the measurement time in the memory 140 or the wireless communication circuit 150. To the external device via Therefore, in this thermometer 1, if it is not determined that the second region 22 is in contact with the body surface 15s, temperature measurement is not performed, and effective data is not output. For this reason, it is possible to increase the accuracy of the body surface temperature Ta and the like measured by omitting useless temperature measurement. Moreover, since consumption of the battery 13 can be suppressed, the body surface temperature Ta and the like can be measured over a long period of time. Therefore, it is possible to provide a portable thermometer 1 that can acquire highly accurate data for a long time.

  As described above, the thermometer 1 is provided with the first region 21 for measuring the temperature of the body surface 15 s on the lower surface 2 a, further provided with the second region 22 so as to surround the first region 21, and the second region 22. It is determined whether or not the region of the first region 21 is in contact with the body surface 15s depending on whether or not is in contact with the body surface 15s. For this reason, it is not necessary to install a sensor for confirming the presence or absence of contact in the first region 21, and the first region 21 can be occupied for temperature measurement on the body surface or in the deep part of the body. It can be designed in the optimum state for temperature measurement of the surface. In this thermometer 1, the temperature sensor 7 is disposed so as to be close to the body surface 15 s at a distance that separates the wall surface 29 a of the first region 21 of the case 2, and the back surface (back side) of the temperature sensor 7 is wide. By covering the region with the heat insulating material 25, a highly accurate body surface temperature Ta is obtained.

  Moreover, in this thermometer 1, the 1st area | region 21 and the 2nd area | region 22 are provided in the same lower surface 2a, and the body surface 15s of the 1st area | region 21 by the presence or absence of the contact with respect to the body surface 15s of the 2nd area | region 22 The presence or absence of contact with is judged. Therefore, in the thermometer 1, it is sufficient that the surface 2a is in close contact with or in contact with the body surface 15s so that the sensor 5 can detect that the second region 22 is in contact with the body surface 15s. There is no need to press against the body 15. Therefore, it is possible to provide a thermometer 1 that can easily measure the body temperature with less burden on the user's body.

  Moreover, in this thermometer 1, it is not necessary to provide the part which protruded from case 2 in order to press a sensor to a body, and it is not necessary to provide the probe which the front-end | tip protruded. Therefore, it is possible to design the case 2 in a thin box shape or plate shape in which at least one outer surface is flat or gently curved, and it is attached to the surface of the living body like a bandage to accurately acquire biological information. It is also possible to provide a device. It is relatively easy to wear for a long time, and a device that does not get in the way when lying down can be provided.

  In this thermometer 1, a ring-shaped first electrode 6 a and a second electrode 6 b are used as sensors 5 that determine whether or not the second surface 22 surrounding the first region 21 is in contact with the body surface 15 s. Are arranged concentrically. The electrostatic capacitance SC between the annular electrodes 6a and 6b changes depending on the contact condition of the annular electrodes 6a and 6b with respect to the body surface 15s. Therefore, the annular electrodes 6a and 6b are one of the most suitable forms as the sensor 5 that captures the presence or absence of contact of the second region 22 with the body surface 15s and ensures the contact of the first region 21 with the body surface 15s. One.

  As shown in FIGS. 6 (a) and 6 (b), by disposing a plurality of electrodes 6a and 6b paired with the second region 22, the second region 22 and the body surface 15s It is also possible to determine the presence or absence of contact.

  In the above example, the capacitance between the electrodes is measured to determine the adhesion between the second region 22 and the body surface 15s, but the adhesion is determined by measuring the DC impedance between the electrodes. May be. The DC impedance flowing between the electrodes takes a small value when the electrodes are in contact with the body surface 15s, and takes a very large value when the electrodes are separated. Further, the direct current impedance increases as the fat below the body surface increases. Therefore, by measuring the DC impedance, it is possible to appropriately correct the heat conduction coefficient when calculating the temperature Tc of the deep part of the body.

  Moreover, although the example which used the thermistor as a temperature sensor was demonstrated above, a platinum resistance temperature sensor, a thermocouple, an IC-ized temperature sensor, etc. can be used as a temperature sensor. Furthermore, although the present invention has been described by taking as an example a thermometer that measures body temperature (body surface temperature) as biological information, the present invention can also be applied to an apparatus that measures biological information such as an electrocardiogram, blood pressure, pulse, and respiration.

1 Thermometer 2 Case, 2a One outer surface (lower surface), 2b The other outer surface (upper surface)
21 1st area | region, 22 2nd area | region 6a, 6b Electrode 7, 8 Temperature sensor 9 1st member 10 Control unit 15 Human body 120 Temperature measurement circuit 130 Capacity measurement circuit 140 Memory 150 Wireless communication circuit

Claims (11)

An apparatus for measuring biological information,
A case including a flat or gently curved first surface that contacts the living body;
A first sensor for obtaining first information indicating a state of the surface of the living body via a first region of the first surface;
Second information including information indicating a contact state between the surface of the living body and the second region is obtained via a second region surrounding the first region of the first surface; A sensor ,
A third sensor for measuring the temperature of the second surface of the case that does not contact the living body;
A first member disposed between the first region of the first surface and the second surface ;
The first sensor is a temperature sensor for acquiring a body surface temperature;
The third sensor is a temperature sensor that measures a case outer surface temperature when heat obtained from the first region of the first surface is released from the second surface via the first member. Yes, and
An apparatus having a function of calculating a temperature of a deep part of the body based on the body surface temperature, the case outer surface temperature, the heat conduction coefficient of the first member, and the assumed body heat conduction coefficient . In claim 1,
The function of calculating the temperature of the deep part of the body includes a function of correcting the assumed heat conduction coefficient in the body based on the second information. In claim 1 or 2 ,
The case is an apparatus in which at least one outer surface is a flat box or a thin box shape or a plate shape that is gently curved, and the first surface is at least a part of the one outer surface. In any of claims 1 to 3 ,
And a control unit for processing the first information obtained by the first sensor and / or the second information obtained by the second sensor,
The second sensor includes a plurality of electrodes facing the second region and arranged to surround the first region;
Further, the control unit includes a function of acquiring capacitance and / or DC impedance between the plurality of electrodes as the second information. In claim 4 ,
The plurality of electrodes include an annular first electrode disposed so as to surround the first region, and an annular second electrode disposed so as to surround the first electrode. apparatus. According to claim 4 or 5,
The control unit further includes a function of associating and processing the first information and the second information. In any of claims 1 to 5 ,
Furthermore, the side opposite to the first surface of the first sensor facing the first region of the first surface is covered including the side opposite to the first region of the first surface. A device having thermal insulation. In any one of claims 4 to 6, wherein the control unit including a function of calculating the temperature of the body deep, device. A method for measuring biological information with a device that at least partially contacts a living body,
The apparatus includes a case that includes a flat or gently curved first surface that contacts the living body, and first information that indicates a state of the surface of the living body via a first region of the first surface. A first sensor that obtains the information and a second region that surrounds the first region of the first surface and includes information indicating a contact state between the surface of the living body and the second region. A second sensor that obtains information of the second, a third sensor that measures a temperature of a second surface that does not contact the living body of the case, the first region of the first surface, and the first A control unit for processing a first member arranged between the two surfaces and the first information obtained by the first sensor and / or the second information obtained by the second sensor And the first sensor is a temperature sensor that acquires a body surface temperature. Ri,
The method is
The control unit associating and processing the first information and the second information;
Measuring a case outer surface temperature when heat obtained from the first region of the first surface is released from the second surface through the first member by the third sensor;
Calculating a deep body temperature from the body surface temperature, the case outer surface temperature, the heat conduction coefficient of the first member, and the assumed body heat conduction coefficient.
In claim 9,
The association processing includes outputting the first information when it is determined by the second information that the second region is in contact with the living body. 11. The method according to claim 9, wherein calculating the deep body temperature includes correcting the assumed heat conduction coefficient in the body by the second information.

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