Sleep inducing device

Abstract

To provide sleep inducing device for adapting a deep body temperature of a user to a biorhythm from a time of going to bed to a time of falling asleep.SOLUTION: A device for providing thermal stimulation to a user to induce sleep, includes a heater 1 contacting an abdomen 7 of a user U to apply a thermal stimulus, a control unit 3 for controlling energization to the heater 1 to control the thermal stimulus to the abdomen 7, an operation unit 11 for setting operation of the heater 1 to the control unit 3, and holding means 2 for holding the heater 1 in contact with a position out of the abdomen 7 of the user U where the thermal stimulus is applied to the blood flowing through the abdominal aorta.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a sleep promotion device that provides thermal stimulation to a part of the surface of the human body in order to promote sleep. [Background technology]

[0002] The circadian rhythm, which is one of the biological rhythms, is a cycle of about 25 hours that exists in the body, and is adjusted to 24 hours by exposure to sunlight, etc. It is known that such biological rhythms are closely related to human sleep. It is also known that changes in biological rhythms cause changes in the secretion of sleep hormones, deep body temperature, pulse rate, etc. When we focus on the changes in deep body temperature in the biological rhythm of a person who lives a regular life, we can see that it shows a cyclical fluctuation that is high during the daytime active period and low during sleep.

[0003] Therefore, Patent Document 1 describes a thermotherapy device that focuses on the biological rhythm related to body temperature during sleep and promotes comfortable sleep by controlling the heater temperature to increase, decrease or maintain the temperature in accordance with the temperature change curve of the body temperature. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2003-010230 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the thermotherapy device described in Patent Document 1 controls temperature in accordance with the user's biological rhythm from the time the user goes to bed until they wake up, and the temperature control from the time the user goes to bed until they fall asleep is merely to heat the device to a comfortable temperature in order to suppress sympathetic nerve excitation and induce sleep, and temperature control is simply performed to maintain a temperature that the user feels is warm for a certain period of time, and does not promote sleep onset.

[0006] SUMMARY OF THE PRESENT DISCLOSURE ... In view of the above circumstances, the present invention provides a sleep promotion device that adjusts the deep body temperature of a user to the biorhythm from the time the user goes to bed until the onset of sleep. [Means for solving the problem]

[0007] The sleep promotion device according to the present invention is a device that promotes sleep by providing a thermal stimulus to a user, The device is characterized by having a heater that is brought into contact with the user's abdomen to provide a thermal stimulus, a control unit that controls the flow of electricity to the heater to control the thermal stimulus to the abdomen, an operation unit that sets the operation settings of the heater in the control unit, and a holding means that holds the heater in contact with a position on the user's abdomen where the thermal stimulus is provided to the blood flowing through the aorta.

[0008] The holding means is characterized in that it holds the heater in contact with the vicinity of the navel of the user's abdomen.

[0009] Another feature of the present invention is that the holding means is made of an elastic material, and the heater has flexibility.

[0010] In addition, the control unit is preset with a thermal stimulation time, which is the time from when the heater starts to be energized to when the user's deep body temperature rises and then begins to drop, which is obtained empirically, and is characterized in that it starts timing when the heater starts to be energized and ends the energization of the heater when the thermal stimulation time has been counted.

[0011] The device also has a second measuring unit that detects deep body temperature and a calculation unit that calculates the rate of change of the measurement value detected by the second measuring unit, and the control unit is characterized in that it stops the flow of electricity to the heater when the rate of change calculated by the calculation unit changes to negative after the flow of electricity to the heater begins.

[0012] The device also has a cooling unit that cools the user's peripheral area, and the control unit is characterized in that it stops the heater and drives the cooling unit if the rate of change of the calculation unit does not change to negative even after the thermal stimulation time has elapsed. Effect of the Invention

[0013] According to the present invention, the device has a heater that applies thermal stimulation to a part of the surface of the human body to raise the deep body temperature, a second measuring unit that measures the deep body temperature of the human body, and a control unit that controls the time and temperature of the thermal stimulation by the heater.Therefore, the deep body temperature of the human body can be raised by applying thermal stimulation, and then the deep body temperature decreases due to the dissipation of body heat.Therefore, the device can adapt the user's deep body temperature to the biological rhythm and promote sleep onset.

[0014] In addition, by thermally stimulating the abdomen, it is possible to thermally stimulate the blood flowing through the abdominal aorta located below the abdomen, thereby effectively raising the core body temperature.

[0015] In addition, the control unit starts thermal stimulation by the heater, senses that the deep body temperature of the human body has risen, and then controls the heater to stop the thermal stimulation when the deep body temperature begins to drop, thereby adapting the user's deep body temperature to the biorhythm and promoting sleep onset.

[0016] The device also has a cooling unit that cools peripheral parts of the human body, and the control unit controls the cooling unit to operate if no decrease in deep body temperature is observed after the thermal stimulation by the heater is stopped, thereby adapting the user's deep body temperature to the biological rhythm and promoting sleep. [Brief description of the drawings]

[0017] [Figure 1] 1A is a schematic perspective view of a holding means of a sleep promotion device according to the present invention, and FIG. [Diagram 2] 1 is a schematic plan view showing a state in which a sleep promotion device is in use; [Diagram 3] 1A is a control block diagram of a first embodiment of a sleep promotion device, FIG. 1B is a control block diagram of a second embodiment of a sleep promotion device, and FIG. 1C is a control block diagram of a third embodiment of a sleep promotion device. [Figure 4] This is a diagram showing the mechanism of sleep promotion using a sleep promotion device. [Diagram 5] This figure shows the change in deep body temperature and heater temperature over time in sub2 with and without thermal stimulation. [Figure 6] FIG. 13 is a graph showing the change ratio of the parasympathetic nerve index in sub2 before thermal stimulation and after every 5 minutes. [Figure 7] FIG. 1 is a diagram showing changes in core body temperature and peripheral body temperature according to a human biological rhythm. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. Note that each embodiment is merely one embodiment of the present invention, and the embodiment can be changed without changing the gist of the present invention. In this specification, the term "sleep onset latency" refers to the time from when a person goes to bed until when he or she falls asleep.

[0019] [First embodiment] As shown in Fig. 1(a) and Fig. 3(a), the sleep promotion device 100 according to the first embodiment mainly includes a heater 1 for applying thermal stimulation to a part of the surface of the human body, a holding means 2 for holding the heater 1, a control unit 3 for controlling the thermal stimulation of the heater 1, an operation unit 11 for setting the operation of the heater 1 in the control unit 3, and a detection unit 14. The sleep promotion device 100 is attached to a part of the human body by a user U before going to sleep and goes to sleep, thereby shortening the sleep latency time until the user U falls asleep. In this embodiment, as shown in Fig. 2, the sleep promotion device 100 is used to apply thermal stimulation to the abdomen 7 of the user, but the thermal stimulation site is not limited as long as the deep body temperature can be increased.

[0020] The abdomen 7 to be thermally stimulated is divided into nine sections: right hypochondrium, epigastric region, left hypochondrium, right flank region, umbilicus, left flank region, right iliac region, lower abdomen, and left iliac region, and the heater 1 is held near the umbilicus by holding means 2. Because the abdominal aorta is located below the navel, it is possible to thermally stimulate the blood flowing through the artery, and the core body temperature can be raised efficiently.

[0021] Although not shown in the drawings, the sleep promotion device 100 is provided with a thin battery that supplies power to the machinery of the first measuring unit 4 and the heater 1. The battery is held inside the holding means 2 and is not visible on the surface of the sleep promotion device 100, but a connector for charging the battery from the outside is provided on the surface of the sleep promotion device 100. Usually, the battery is charged in advance before using the sleep promotion device 100, but if the battery has not been charged when the sleep promotion device 100 is to be used, it is possible to use the sleep promotion device 100 while charging it. In this case, a magnetic connector is preferably used so that the connector can be easily detached when the user U of the sleep promotion device 100 turns over in his / her sleep.

[0022] (About heater 1) The heater 1 is for thermally stimulating a part of the user's body, and a highly flexible planar heater is used so that it can easily come into close contact with the uneven human body. As shown in FIG. 1(b), the surface of the heater 1 that comes into contact with the human body is made of a sheet material 8 made of a material with excellent thermal conductivity such as aluminum, which increases the efficiency of thermal conduction. The heater 1 is flexible because it is formed thinly to be planar. Therefore, it can change its shape to fit the curved surface of the abdomen of the user U, and the adhesive area between the abdomen and the heater 1 can be increased. In addition, the heater 1 is formed of a carbon material, so that the heating element is close to a perfect black body, and it can also generate radiant heat such as far infrared rays. At the same time as transmitting heat as conductive heat, the heat is easily transmitted to the deep part of the abdomen due to the effect of radiant heat, so that it can effectively thermally stimulate the blood flow of the abdominal aorta located deep in the abdomen.

[0023] (Regarding holding means 2) The holding means 2 is used to keep the heater 1 in contact with a part of the surface of the user U's body and to prevent heat from the heater 1 from diffusing outward. In this embodiment, the holding means 2 is a flexible and stretchable belly band. The holding means 2 keeps the heater 1 in contact with the abdomen 7 of the user U and stably holds it on the abdomen 7. The holding means 2 comes into close contact with the body of the user U, so that the heater 1 fixed to the holding means 2 also comes into contact with the body of the user U.

[0024] The belly band is preferably made of natural fibers used in underwear, such as cotton, linen, or wool. If necessary, the holding means 2 may have fine holes, and the provision of a large number of fine holes can increase breathability. The holding means 2 may be detachable from the heater 1 or electronic device, and it is also possible to replace only the holding means 2. Therefore, by washing the holding means 2 or replacing it with a new one, it is less likely to cause skin rash or discomfort even when worn for a long time. In addition, the material of the holding means 2 may be a chemical fiber such as polyester, and by using a chemical fiber, it can have water absorption, quick drying, and elasticity compared to natural fibers. The sleep promotion device 100 may be attached over the underwear.

[0025] In this way, the holding means 2 is stretchable and unlikely to cause skin rash or discomfort even when worn for a long time, so the user U will not want to remove the sleep promotion device 100. Therefore, the thermal stimulation is not interrupted, and the above-mentioned configuration of the holding means 2 can effectively promote sleep. Since the heater 1 is in contact with the body of the user U by the holding means 2 being in close contact with the body of the user U, it is preferable that the heater 1 is stretchable so that it can expand and contract in response to the expansion and contraction of the holding means 2 due to the body movement of the user U, and is formed of a conductive material so that an electrical signal can be obtained even when the heater 1 is expanded.

[0026] The shape of the belly band that is the holding means 2 may be cylindrical or a sheet-like shape having connection parts at both ends that allow the length to be adjusted, such as hook-and-loop fasteners or buckles. In addition, the holding means 2 does not have to be a flexible and stretchable belly band type, and may be a wearable type such as a T-shirt or a stick-on type using an adhesive such as double-sided tape, as long as it can stably hold the heater 1 on the abdomen 7. In addition, a substrate 2a is provided in the center of the holding means 2. A display unit 10 and an operation unit 11 are provided on the substrate 2a.

[0027] (Regarding control unit 3) The control unit 3 is provided in the holding means 2 and controls the thermal stimulation of the heater 1 . The control unit 3 may control the heater 1 to operate at a set temperature for a certain period of time to provide thermal stimulation, or may control the heater 1 to gradually increase the temperature. In addition, by providing thermal stimulation, as described later, it is possible to promote a drop in the deep body temperature after the deep body temperature has risen, which results in a change in the deep body temperature that is in line with the biological rhythm, and thus it is possible to promote sleep onset. The thermal stimulation time of the heater 1 is set in advance by the user U, and the timing starts when the heater 1 is energized, and the energization ends after the set time has elapsed. The thermal stimulation time is the time from the start of energization of the heater 1 until the deep body temperature of the user U starts to rise and then to drop, which is empirically obtained. The time from the start of energization of the heater 1 until the deep body temperature of the user U starts to rise and then to drop is different for each individual, so it is necessary to measure the change in the deep body temperature over time in advance and empirically obtain the time from the start of energization of the deep body temperature until the deep body temperature starts to drop after rising.

[0028] Feedback control is preferably used for the temperature control of the control unit 3. As shown in Fig. 3, when a certain temperature is set as a target temperature, the heat quantity of the heater 1 is transferred to the user U, and the detection unit 14 determines that the temperature of the heater 1 has become lower than the set temperature, and the actual temperature of the heater 1 is fed back to the control unit 3, thereby controlling the temperature to compensate for the difference from the set temperature. The current passed through the heater 1 is pulse width modulated (PWM) which repeatedly turns on and off in a one-second cycle, and the heater 1 is operated by the pulsed current under PI control.

[0029] (Regarding the operation unit 11) The operation unit 11 is a switch for operating the temperature and time settings of the heater 1. It is attached to the front side of the sleep promotion device 100. When the operation unit 11 is attached to the sleep promotion device 100, operability can be improved by providing the operation unit 11 on the side closer to the dominant hand.

[0030] Specifically, the operating unit 11 can be used to operate the power supply of the sleep promotion device 100, set the temperature of the heater 1 from 30°C to 60°C, set the thermal stimulation time from 5 to 50 minutes, and set the temperature and duration of the cooling unit 12, which will be described later.

[0031] [Regarding the second embodiment] 3(b) shows a control block diagram of the sleep promotion device 200 in the second embodiment. The heater 1, holding means 2, control unit 3, operation unit 11, and detection unit 14 are the same as those in the sleep promotion device 100 in the first embodiment. The sleep promotion device 200 is newly provided with a first measurement unit 4, a second measurement unit 5, a third measurement unit 6, a calculation unit 9, and a display unit 10.

[0032] (Regarding control unit 3) The functions of the heater 1 and the cooling unit 12 of the sleep promotion device 200 are executed under the control of the control unit 3. The first measurement unit 4, the second measurement unit 5, and the third measurement unit 6 are processed by the calculation unit 9, and the control unit 3 executes a program stored in the memory after the calculation, so that the function of the heater 1 of the sleep promotion device 200 is fulfilled. In this embodiment, the heater 1 may be controlled so that the heater 1 is operated to start a thermal stimulation, and the calculation unit 9 confirms the inflection point of the deep body temperature when the deep body temperature starts to decrease after the second measurement unit 5 detects that the deep body temperature of the human body has increased, and then the heater 1 is stopped from being energized and the thermal stimulation is stopped. Specifically, the thermal stimulation may be stopped at the same time as the rate of change of the deep body temperature becomes negative from positive and a signal indicating that the inflection point of the deep body temperature has been confirmed is sent from the calculation unit 9, or the heater 1 may be stopped from being energized and the thermal stimulation is stopped after a certain time (for example, 30 seconds to 1 minute) has passed since the signal was sent, and the decrease in the deep body temperature is confirmed. When the thermal stimulation time is preset, the thermal stimulation is controlled to stop when the inflection point is confirmed even before the thermal stimulation time has elapsed. By controlling in this way, as will be described later, it is possible to promote a decrease in deep body temperature after the deep body temperature has risen, resulting in a change in deep body temperature that is compatible with the biological rhythm, and thus promoting sleep onset.

[0033] (Regarding the first measuring unit 4) The first measuring unit 4 is a measuring device that measures the user's peripheral body temperature. Peripheral body temperature is the temperature of the skin of the toes, fingertips, dorsum of the foot, etc., and the site to be measured is not particularly limited. Peripheral body temperature is easily affected by the outside air because the amount of heat produced is small, so it is desirable to measure it in an environment with little influence of external disturbance. In this embodiment, the first measuring unit 4 is attached to the left hand of the user U as shown in FIG. 2. The first measuring unit 4 is wirelessly connected to the calculation unit 9 provided inside the holding means 2. In addition, the first measuring unit 4 may be attached inside the holding means 2 if possible, or may be connected by wire without using wireless.

[0034] (Regarding the second measuring unit 5) The second measuring unit 5 is a measuring device that measures the deep body temperature of the user. The deep body temperature is the temperature of the eardrum, rectum, pharynx, esophagus, bladder, etc. While the method of measuring the rectal temperature is highly accurate, it is necessary to insert a temperature probe directly into the body from the anus to measure the temperature inside the rectum, which places a large burden on the user and makes it difficult to measure continuously in daily life. Therefore, the deep body temperature may be measured by a method that measures the movement of heat emitted from the body surface. In this embodiment, the second measuring unit 5 is attached to the left hand of the user U as shown in FIG. 2. The second measuring unit 5 is connected wirelessly to the calculation unit 9 provided inside the holding means 2. If possible, the second measuring unit 5 may be attached inside the holding means 2, or may be connected by wire without using wireless.

[0035] (Regarding the third measuring unit 6) The third measuring unit 6 is for measuring the state of the enhanced activity of the sympathetic and parasympathetic nerves of the user. In this embodiment, the third measuring unit 6 is a pulse measuring device that measures the pulse, and the enhanced state of the sympathetic and parasympathetic nerve activities can be confirmed from the measured value of the user's pulse obtained. In this embodiment, the third measuring unit 6 is attached to the left hand of the user U as shown in FIG. 2. The third measuring unit 6 is wirelessly connected to the calculation unit 9 provided inside the holding means 2. In addition, the third measuring unit 6 may be attached inside the holding means 2 if possible, or may be connected by wire without using wireless.

[0036] (Regarding the calculation unit 9) The calculation unit 9 is provided in the holding means 2 and is a part that performs calculations such as calculations on numerical values. Information on each measurement value obtained from the first measurement unit 4, the second measurement unit 5, and the third measurement unit 6 is sent to the calculation unit 9, and the calculation unit 9 calculates the rate of increase or decrease of each measurement value after each time elapses. The calculation unit 9 differentiates the specific numerical values ​​of the peripheral body temperature and the deep body temperature with respect to time, determines the inflection point where the rate of change of the peripheral body temperature and the deep body temperature turns from positive to negative, and transmits the information to the control unit 3.

[0037] (Regarding the display unit 10) The display unit 10 displays the peripheral body temperature of the human body measured by the first measuring unit 4, the deep body temperature measured by the second measuring unit 5, the pulse rate measured by the third measuring unit 6, the activation state of the sympathetic and parasympathetic nerves, the set temperature of the heater 1, the thermal stimulation time, etc., as a display screen such as a display. In this embodiment, the display unit 10 is attached to the surface of the sleep promotion device 200. The operation unit 11 and the display unit 10 may be integrated, or the display screen of the display unit 10 may be configured to allow operation as a pressure-sensitive touch panel.

[0038] [Third embodiment] 3(c) shows a control block diagram of a sleep promotion device 300 in the third embodiment. The heater 1, holding means 2, control unit 3, first measurement unit 4, second measurement unit 5, third measurement unit 6, calculation unit 9, display unit 10 and operation unit 11 are the same as those of the sleep promotion device 200 in the second embodiment. The sleep promotion device 300 is newly provided with a cooling unit 12 and a communication unit 13. The display unit 10 and operation unit 11 in the third embodiment are external devices such as a smartphone, and are capable of communicating with the calculation unit 9 in the sleep promotion device 300 via the communication unit 13.

[0039] (Regarding the cooling section 12) In this embodiment, as shown in FIG. 2 and FIG. 3(c), the control unit 3 is connected to the heater 1 and the cooling unit 12. The cooling unit 12 is a device such as a Peltier element that is attached to the peripheral parts of the human body, such as the user's toes and fingertips, and cools the peripheral parts. By cooling the peripheral parts with the cooling unit 12, the peripheral body temperature is lowered, and the deep body temperature, which is the temperature of the internal organs located inside the human body, can also be efficiently lowered. In particular, when the heat amount of the thermal stimulation is greater than the heat amount of the thermal radiation even after the thermal stimulation by the heater 1 is stopped, and the deep body temperature does not decrease, the cooling unit 12 is preferably used to lower the peripheral body temperature, and can promote the lowering of the deep body temperature. In this embodiment, the cooling unit 12 is driven by a separately connected battery power source by a wireless instruction signal from the control unit 3, and may be connected by wire instead of wireless.

[0040] The control unit 3 may control the cooling unit 12 to operate if, even after the heater 1 is stopped, no drop in deep body temperature is observed due to the influence of disturbances, etc., and the rate of change in deep body temperature does not change from positive to negative and no inflection point is observed. By driving the cooling unit 12 attached to a peripheral part of the human body, the peripheral body temperature can be lowered, and the deep body temperature can also be lowered, resulting in a change in deep body temperature that is compatible with the biological rhythm, which can promote sleep onset.

[0041] (Regarding communication unit 13) In this embodiment, the communication unit 13 wirelessly connects the calculation unit 9 and the display unit 10 to the control unit 3 and the operation unit 11. The communication unit 13 wirelessly communicates various data with external devices. The communication unit 13 can be configured using a wireless communication device that complies with general wireless communication standards such as wireless LAN and mobile phone lines. Alternatively, the communication unit 13 may be connected via a network such as the Internet using a router or the like. The operation unit 11 and the display unit 10 may be operated by an external device such as a smartphone via wireless communication via the communication unit 13. By connecting to an external device such as a smartphone, the user can easily check and operate the settings of the heater 1 and the cooling unit 12 while wearing the sleep promotion device 100.

[0042] Furthermore, if the external device is provided with a storage device, it is possible to check the user's sleep time, the temperature setting of the heater 1, the thermal stimulation time, the changes in peripheral body temperature and deep body temperature over time, and the state of parasympathetic nervous activity. From these results, the user U can obtain feedback and appropriately change the settings of the heater 1 and the cooling unit 12 to find the optimal temperature and time.

[0043] Similarly, the calculation unit 9 and the control unit 3 may be connected to an external device such as a smartphone so as to enable wireless communication. Also, the sleep promotion devices 100 and 200 may be provided with an input / output unit and connected by wire to an external device provided with the calculation unit 9, the control unit 3, the display unit 10, or the operation unit 11. Of course, the cooling unit 12 may also be provided in the first and second embodiments.

[0044] [Mechanism of sleep promotion] Next, the mechanism of sleep promotion by thermal stimulation using the sleep promotion devices 100, 200, and 300 will be specifically described with reference to Fig. 4 and Fig. 7, from thermal stimulation by the heater 1 to promotion of sleep (STEP 1 to 15). Fig. 4 shows a mechanism diagram of a model case of the mechanism of sleep promotion by thermal stimulation. The letters S in the diagram indicate the steps described below.

[0045] (STEP 1) When a thermal stimulus is applied by the heater 1 with the target temperature set, the temperature of the biological tissue and blood in the vicinity of the heater 1 increases. When the heater 1 is attached to the navel of the abdomen 7 of the user U, a thermal stimulus is applied to the surface of the navel, and the temperature of the biological tissue in the vicinity of the navel and the blood flowing in the abdominal aorta located below the navel increases.

[0046] (STEP 2) As the temperature of the blood flowing through the abdominal aorta rises, the heated blood circulates throughout the body. This causes the heat from the heater 1 to be diffused throughout the body via the bloodstream.

[0047] (STEP 3) As heat is diffused throughout the body, the peripheral body temperature, which is the temperature of the skin of the fingertips, forearms, toes, etc., rises, and at the same time, the deep body temperature, which is the temperature of the internal organs of the body, also rises. Both the peripheral body temperature and the deep body temperature rise, but the peripheral body temperature rises more predominantly. The peripheral body temperature and the deep body temperature are measured by the first measuring unit 4 and the second measuring unit 5.

[0048] (STEP 4) The deep body temperature receptors and skin temperature receptors in the user U's body detect information about the rise in deep body temperature and peripheral body temperature, and the detected temperature information is sent via nerves to the hypothalamus, the brain's thermoregulatory center, and the brain detects the rise in temperature, especially the deep body temperature.

[0049] (STEP 5) The thermoregulatory center transmits information to the effector organs involved in dispersing heat outside the body to maintain an optimal body temperature. Specifically, it transmits heat to the sweat glands through sweating, and it acts on the skin blood vessels to suppress sympathetic nerve activity as vasoconstrictor nerves and dilate the blood vessels.

[0050] (STEP 6) By suppressing sympathetic nerve activity as a vasoconstrictor and expanding the diameter of blood vessels, the amount of blood flowing to peripheral areas increases, and the effect on the circulatory system begins. As the amount of blood flowing to peripheral areas increases, the transfer of body heat to the body surface is promoted, and the dissipation of body heat is promoted.

[0051] (STEP 7) As body heat begins to radiate out from the body, the peripheral body temperature measured at the outer parts of the body, such as the toes and fingertips, drops before the core body temperature.

[0052] (STEP 8) After that, as the peripheral body temperature drops, the core body temperature, which is the temperature of the internal organs located inside the human body, also drops. As a result, the core body temperature rises, passes an inflection point, and then drops, following the same curve as the biological rhythm. As a result, falling asleep is promoted.

[0053] (STEP 9) If the set temperature of the heater 1 is too high, the room temperature is too high, or the thermal stimulation is continued without stopping the heater 1, the amount of heat generated by the thermal stimulation will be greater than the heat dissipation. In this case, the temperature of the living tissue and blood near the heater 1 will continue to rise, and the heated blood will circulate in the body.

[0054] (STEP 10) Furthermore, as the heated blood circulates throughout the body, the peripheral body temperature continues to rise, and as a result, the core body temperature also continues to rise.

[0055] (STEP 11) Furthermore, the deep body temperature receptors and skin temperature receptors detect information about increases in deep body temperature and peripheral body temperature, and the detected temperature information is sent via nerves to the hypothalamus, the brain's thermoregulatory center, and the brain detects increases in temperature, particularly deep body temperature.

[0056] (STEP 12) Furthermore, the thermoregulatory center transmits information to the effector organs involved in dispersing heat outside the body to maintain an optimal body temperature. Specifically, it radiates heat to the sweat glands through sweating, and it stimulates sympathetic nerve activity as a vasodilator in the skin's blood vessels, causing them to dilate.

[0057] (STEP 13) By enhancing sympathetic nerve activity as a vasodilator nerve, the diameter of blood vessels is expanded, increasing the amount of blood flowing to peripheral areas, and the effect on the circulatory system begins. As the amount of blood flowing to peripheral areas increases, the transfer of body heat to the body surface is promoted, and the dissipation of body heat is promoted.

[0058] (STEP 14) As body heat begins to radiate from the body to the outside, the peripheral body temperature measured at the extremities, such as the toes and fingertips, drops before the core body temperature.

[0059] (STEP 15) After that, as the peripheral body temperature drops, the core body temperature, which is the temperature of the internal organs located inside the human body, also drops. As a result, the core body temperature rises, passes an inflection point, and then drops, following the same curve as the biological rhythm. As a result, falling asleep is promoted. If the amount of heat generated by the thermal stimulus is greater than the heat dissipation, the state returns to (STEP 9), and the person is unable to fall asleep or the sleep effect is reduced.

[0060] <Sleep experiment> Next, the sleep experiment will be described with reference to Figs. 5, 6, and Tables 1 and 2. In the sleep experiment, the sleep promotion device 100, a deep body temperature measuring device, a peripheral body temperature measuring device, and an electroencephalogram measuring device were used to verify the effects of promoting sleep with and without thermal stimulation. This experiment was conducted as a control experiment in which all conditions were the same except for whether or not thermal stimulation was present. The following describes "1. User (experimental subject)", "2. Experimental device", "3. Experimental conditions", "4. Experimental procedure", and "5. Experimental results" of the sleep experiment.

[0061] (1. About the users (experimental subjects)) The users (experimental subjects) were six healthy adults (three men and three women). Hereinafter, they will be referred to as sub1 to sub6, respectively.

[0062] (2. Experimental Equipment) The following measuring instruments were used as experimental equipment: The onset of sleep was judged by measuring electroencephalograms using Polymate Pro (Miyuki Giken Co., Ltd.) and judging by the disappearance of alpha waves and the appearance of parietal sharp waves. Core temperature was measured using a CoreTemp (Terumo Corporation). Peripheral body temperature was measured using Polymate Pro (Miyuki Giken Co., Ltd.).

[0063] (3. Experimental conditions) The experimental environment was darkness, with the subject lying on his / her back on a bed with a blanket over him / her. The room temperature was set to 28°C ± 2°C. The site of thermal stimulation was the navel of the abdomen. The heater 1 was held in place by a belly band over the underwear. The contact area between the heater 1 and the navel was approximately 144 cm2. 2 The target temperature of the thermal stimulation was set to the maximum temperature that sub1 to 6 could tolerate, the temperature was kept constant, and the thermal stimulation time was set to 30 minutes.

[0064] (4. Experimental Procedures) For subs 1 to 6, subjects were asked to lie on their backs under a duvet. They were instructed not to fall asleep for the first 5 minutes after going to bed in order to obtain a baseline for autonomic nervous indexes. After that, they were instructed to undergo thermal stimulation for 25 minutes so that they would fall asleep. The time from going to bed to falling asleep and the change in deep body temperature were measured.

[0065] (5. Experimental Results) The results of the sleep experiments are shown in Tables 1 and 2 and Figures 5 and 6.

[0066] [Table 1] shows, for subs 1 to 6, the sleep latency time (minutes:seconds) with thermal stimulation, the sleep latency time (minutes:seconds) without thermal stimulation, and the time (minutes:seconds) obtained by subtracting the time without thermal stimulation from the time with thermal stimulation, under each set temperature condition of heater 1 of sleep promotion device 100. In other words, when the subtracted time is negative, it indicates that the sleep latency time was shortened by using sleep promotion device 100.

[0067] [Table 1]

[0068] In Table 1, for subs 1, 2, 4, and 6, the sleep onset latency was shorter when the sleep promotion device 100 was used, but for subs 3 and 5, no shortening of the sleep onset latency was confirmed even when the sleep promotion device 100 was used. When the sleep promotion device 100 was used, the sleep onset latency was shortened for four out of six subjects, and the total shortened time was 5 minutes 53 seconds, which was greater than the total extended time of 2 minutes 31 seconds for subs 3 and 5, for which no shortening of the sleep onset latency was confirmed. Therefore, overall, it was confirmed that the use of the sleep promotion device 100 shortened the sleep onset latency and promoted sleep onset.

[0069] For sub3 and 5, the reason for the increased sleep latency is thought to be the phenomenon from (STEP 9) onwards. The amount of heat generated by the thermal stimulus is greater than the heat dissipation, which is thought to be why the sleep latency is increased. Therefore, for sub3 and 5, by setting the above temperature setting low, the phenomenon from (STEP 9) onwards can be eliminated, and sleep onset can be promoted. As such, the optimal temperature for the heater 1 differs depending on the user, so it is necessary to empirically set a temperature suitable for the user.

[0070] [Table 2] shows, for subs 1 to 6, the changes in the user's core body temperature, peripheral body temperature, and parasympathetic nervous activation before and after falling asleep, depending on whether or not thermal stimulation by the heater 1 of the sleep promotion device 100 is applied.

[0071] [Table 2]

[0072] In [Table 2], only three out of six people were able to confirm an increase in peripheral body temperature without thermal stimulation, but all six out of six people were able to confirm an increase in peripheral body temperature with thermal stimulation. On the other hand, two out of six people were able to confirm an increase in deep body temperature without thermal stimulation, and only one out of six people were able to confirm an increase in peripheral body temperature with thermal stimulation, with almost no change being confirmed. This is thought to be because, as shown in (STEP 3), the heater 1 of the sleep promotion device 100 diffuses heat throughout the body, causing peripheral body temperature, which is the temperature of the skin of the fingertips, forearms, and toes, to rise, and at the same time, deep body temperature, which is the temperature of the internal organs of the body, to rise, but the peripheral body temperature rose more than the deep body temperature. As for the enhancement of parasympathetic nerves, one more person was able to confirm an increase with thermal stimulation compared to the case without thermal stimulation, so it is thought that the use of the sleep promotion device 100 promoted falling asleep.

[0073] Figure 5 shows the deep body temperature over time for sub2 with and without thermal stimulation, and the temperature of heater 1 over time. For the first five minutes, no thermal stimulation is applied to obtain a baseline for the autonomic nerve index, resulting in a value of around 37°C. After five minutes, the temperature of heater 1 begins to rise, and thermal stimulation is applied to reach the set temperature of heater 1, 48°C. The set temperature of heater 1 is set to 48°C, but the temperature is balanced at around 41°C due to heat loss.

[0074] After falling asleep, the deep body temperature gradually increases compared to when the sleep promotion device 100 is not being used. About two minutes after the start of thermal stimulation by the heater 1, i.e., about seven minutes after falling asleep, the deep body temperature begins to decrease and an inflection point occurs, indicating that the body temperature change is in line with the biological rhythm.

[0075] In this way, it can be seen that the deep body temperature rises and then drops when thermal stimulation is applied compared to when thermal stimulation is not applied. By raising and then lowering the deep body temperature during the sleep latency period to match the biological rhythm, it is possible to promote sleep compared to when the sleep promotion device 100 is not being used.

[0076] In this experiment, the heater 1 was controlled so that it remained constant after 5 minutes had passed since the subject went to sleep, but the thermal stimulation of the heater 1 may be stopped at the inflection point 7 minutes after the subject went to sleep. By controlling the heater 1 in this way, the core body temperature can be further lowered, and the onset of sleep can be further promoted.

[0077] FIG. 6 shows the change ratio calculated by using the parasympathetic nerve index measured for 5 minutes before the thermal stimulation as the denominator and the parasympathetic nerve index measured immediately after heating to 5 minutes after heating, 5 to 10 minutes after the thermal stimulation, 10 to 15 minutes after the thermal stimulation, 15 to 20 minutes after the thermal stimulation, and 20 to 25 minutes after the thermal stimulation as the numerators. It can be seen that the parasympathetic nerve activity is inferior until 5 minutes have passed, but after the thermal stimulation starts 5 minutes after the thermal stimulation, the parasympathetic nerve gradually becomes dominant even after falling asleep. On the other hand, it can be seen that the parasympathetic nerve activity gradually decreases after falling asleep without the thermal stimulation. This shows that the thermal stimulation by the sleep promotion device 100 not only promotes falling asleep, but also relaxes the brain during sleep, allowing a good quality sleep to be obtained. [Explanation of symbols]

[0078] 100,200,300 Sleep aid device 1 Heater 2 Holding means 2a board 3. Control Unit 4 1st measurement section 5 Second measuring section 6 Third measurement section 7 Abdomen 8 Sheet material 9 Arithmetic section 10 Display 11 Operation section 12 Cooling Section 13 Ministry of Communications U User

Claims

1. A device that provides a user with a thermal stimulus to promote sleep, A heater that is in contact with the abdomen of the user to provide a thermal stimulus; A control unit controls the power supply to the heater to control the thermal stimulation to the abdomen; an operation unit for setting the operation of the heater in the control unit; a holding means for holding the heater in contact with a position of the abdomen of the user where a thermal stimulus is applied to the blood flowing through the aorta; A sleep promotion device comprising:

2. 2. The sleep promoting device according to claim 1, wherein the holding means holds the heater in contact with the abdomen of the user in the vicinity of the navel.

3. 3. The sleep promoting device according to claim 1, wherein the holding means is made of an elastic material, and the heater is flexible.

4. The control unit is preset with a thermal stimulation time obtained empirically from the start of energizing the heater to the time when the user's deep body temperature rises and then begins to decrease, and starts timing from the start of energizing the heater and ends energizing the heater when the thermal stimulation time has been counted.

5. A second measuring unit that detects deep body temperature; A calculation unit that calculates a rate of change of the measurement value detected by the second measurement unit, 2. The sleep promotion device according to claim 1, wherein the control unit stops energizing the heater when the rate of change calculated by the calculation unit becomes negative after energization of the heater is started.

6. A second measuring unit that detects deep body temperature; A calculation unit that calculates a rate of change of the measurement value detected by the second measurement unit, The sleep promotion device according to claim 4, characterized in that the control unit stops energizing the heater when the rate of change calculated by the calculation unit becomes negative after energizing the heater, even before the predetermined thermal stimulation time has elapsed.

7. The device further includes a cooling unit for cooling a peripheral area of ​​the user, The sleep promotion device according to claim 6, wherein the control unit stops the heater and drives the cooling unit when the rate of change of the calculation unit does not change to negative even after the thermal stimulation time has elapsed.

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