Bathtub equipment

Abstract

To provide a bathtub device which can acquire a sufficient fatigue recovery effect without depending on an individual difference between bathers or usage of the bathers.SOLUTION: A bathtub device (1) includes: a bathtub body (2); a biological information acquisition part (56) for detecting or estimating a heart rate or a blood flow of a bather; a heating / cooling device for imparting a warm feeling stimulation higher than a predetermined reference temperature or a cool feeling stimulation lower than a predetermined reference temperature to a bather; and a control part (64) for controlling the heating / cooling device based on the heart rate or the blood flow. The control part imparts a cooling stimulation to the bather by controlling the heating / cooling device when the increase of the heart rate or the increase of the blood flow has satisfied a predetermined first condition, and imparts a warm feeling stimulation to the bather by controlling the heating / cooling device when the decrease of the heart rate or the decrease of the blood flow acquired from the biological information acquisition part has satisfied a predetermined second condition.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a bathtub device, and more particularly to a bathtub device that can provide bathers with both warm and cool sensations. [Background technology]

[0002] Japanese Patent Publication No. 2007-29183 (Patent Document 1) describes a blood circulation promoting device. This blood circulation promoting device comprises a bathtub into which the toes can be inserted, a water storage tank, a warm mist generating means that converts the water in the water storage tank into warm mist and supplies it into the bathtub to provide a warm stimulus, and an outside air introduction means that supplies outside air into the bathtub to provide a cold stimulus.

[0003] Japanese Patent Publication No. 2009-394 (Patent Document 2) describes a foot bath. This foot bath comprises a foot bath with an open top, a heating means for heating the water stored in the foot bath, a temperature detection means for detecting the water temperature in the foot bath, and a control means for controlling the amount of heating by the heating means based on the output of the temperature detection means. In addition, a low-temperature tank is provided in a part of the center of the foot bath where the water stored in the foot bath does not flow, and a communication opening is provided between the bottom of the foot bath and the bottom of the low-temperature tank, which is opened and closed by the control means. With this configuration, it is possible to repeatedly immerse the feet in hot water and cold water alternately, aiming to obtain an effect that further improves blood circulation.

[0004] Thus, it is known that repeatedly applying warm and cold stimuli to a part of the human body increases blood flow with warm stimuli and decreases blood flow with cold stimuli, and by repeating this, a further blood circulation-promoting effect can be obtained, thereby promoting recovery from fatigue. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2007-29183 [Patent Document 2] Japanese Patent Publication No. 2009-394 [Overview of the Initiative] [Problems that the invention aims to solve]

[0006] However, according to the inventors' research, there are individual differences in the relationship between warm stimulation and increased blood flow, and between cold stimulation and decreased blood flow. Even when the same warm stimulation is applied, the effect of increasing blood flow differs from person to person, and even when the same cold stimulation is applied, the effect of decreasing blood flow differs from person to person. In this case, the invention described in Patent Document 1 has the problem that, because the warm bath and cold bath are switched at regular intervals, some users may not be able to fully obtain the effect of increasing blood flow from the warm bath or decreasing blood flow from the cold bath, and thus may not be able to recover from fatigue. Furthermore, in the invention described in Patent Document 2, the user has to move their feet between the foot bath and the cold bath of their own volition, which is inconvenient, and depending on how the user uses it, a sufficient fatigue recovery effect may not be obtained.

[0007] Therefore, the present invention aims to provide a bathtub device that can achieve a sufficient fatigue recovery effect regardless of individual differences among bathers or how they use the bathtub. [Means for solving the problem]

[0008] In order to solve the above problems, the present invention provides a bathtub device capable of giving a warm sensation stimulus and a cool sensation stimulus to a bather, comprising: a bathtub body for storing hot water and having a drainage part for discharging the stored hot water; a biological information acquisition part for detecting or estimating the heart rate or blood flow rate of the bather in the bathtub body; a thermo - cold - heat device for giving a warm sensation stimulus higher than a predetermined reference temperature and a cool sensation stimulus lower than the predetermined reference temperature to the bather; and a control part for controlling the thermo - cold - heat device based on the heart rate or blood flow rate acquired by the biological information acquisition part. The control part controls the thermo - cold - heat device to give a cool sensation stimulus to the bather when an increase in the heart rate or an increase in the blood flow rate acquired by the biological information acquisition part satisfies a predetermined first condition, and controls the thermo - cold - heat device to give a warm sensation stimulus to the bather when a decrease in the heart rate or a decrease in the blood flow rate acquired by the biological information acquisition part satisfies a predetermined second condition.

[0009] In the present invention configured as described above, the heart rate or blood flow rate of the bather in the bathtub body storing hot water is acquired by the biological information acquisition part. The control part controls the thermo - cold - heat device for giving a warm sensation stimulus and a cool sensation stimulus to the bather based on the acquired biological information. When an increase in the heart rate or an increase in the blood flow rate acquired by the biological information acquisition part satisfies the first condition, the control part controls the thermo - cold - heat device to give a cool sensation stimulus to the bather, and when a decrease in the heart rate or a decrease in the blood flow rate acquired by the biological information acquisition part satisfies the second condition, the control part controls the thermo - cold - heat device to give a warm sensation stimulus to the bather.

[0010] According to the present invention configured as described above, a cool sensation stimulus is given to the bather based on an increase in the heart rate or an increase in the blood flow rate, and a warm sensation stimulus is given to the bather based on a decrease in the heart rate or a decrease in the blood flow rate. As a result, it is possible to surely give a stimulus that increases and decreases the heart rate to the bather, or a stimulus that increases and decreases the blood flow rate to the bather, and a sufficient fatigue recovery effect can be obtained without depending on individual differences of the bather or the usage method of the bather.

[0011] In the present invention, preferably, after the bather enters the bathtub body, the control unit controls the temperature control device so that the application of a cool feeling stimulus or a warm feeling stimulus to the bather is started based on the heart rate or blood flow rate acquired by the biological information acquisition unit after a predetermined waiting time has elapsed.

[0012] Generally, the heart rate and blood flow rate of a bather may temporarily increase due to undressing, body washing, stepping over the bathtub, or the startle reflex caused by the temperature difference between the body temperature and the temperature of the hot water stored in the bathtub body. The heart rate and blood flow rate obtained in such a state do not accurately reflect the state of the bather's body. According to the present invention configured as described above, after the bather enters the bathtub body, the temperature control device is controlled based on the heart rate or blood flow rate acquired by the biological information acquisition unit after a predetermined waiting time has elapsed. As a result, a cool feeling stimulus or a warm feeling stimulus can be applied based on a highly reliable heart rate or blood flow rate that accurately reflects the state of the bather's body, and a fatigue recovery effect can be surely obtained.

[0013] In the present invention, preferably, it further has a body temperature acquisition unit that acquires the body temperature of the bather, and the control unit changes the waiting time based on the body temperature of the bather acquired by the body temperature acquisition unit.

[0014] According to the present invention configured as described above, since the waiting time is changed based on the body temperature of the bather, a cool feeling stimulus or a warm feeling stimulus can be applied after the body temperature of the bather has reached an appropriate temperature. The bather can enjoy a comfortable bath and also obtain a fatigue recovery effect due to the cool feeling stimulus or the warm feeling stimulus.

[0015] In the present invention, preferably, the biological information acquisition unit is configured to be able to detect or estimate the heart rate of the bather, and the control unit estimates the body temperature of the bather based on the heart rate of the bather.

[0016] When a person is bathing, their body is submerged in water, and generally, it is difficult to detect their body temperature without being affected by the temperature of the water stored in the bathtub. According to the present invention configured as described above, the bather's body temperature is estimated based on the bather's heart rate, so the bather's body temperature can be obtained without burdening the bather.

[0017] In the present invention, preferably, the control unit first provides the bather with a cooling or warming stimulus, and then controls the heating and cooling device to alternately provide the cooling and warming stimulus at predetermined alternation intervals.

[0018] According to the present invention configured in this way, after initially applying a cooling or warming stimulus, the cooling and warming stimuli are applied alternately at predetermined intervals. Therefore, even when heart rate or blood flow cannot be measured, it is possible to prevent the cooling or warming stimulus from being applied continuously for a long period of time.

[0019] In the present invention, preferably, when the control unit first provides a cooling or warming stimulus to the bather, it determines that the first condition is satisfied when the heart rate or blood flow rate rises by a predetermined value from the reference heart rate or blood flow rate, based on the heart rate or blood flow rate when the bather enters the bathtub or after a predetermined waiting time has elapsed after the bather enters the bathtub, and when the heart rate or blood flow rate rises by a predetermined value from the reference heart rate or blood flow rate, and when the heart rate or blood flow rate falls by a predetermined value from the reference heart rate or blood flow rate, and when the control unit first provides a cooling or warming stimulus to the bather, it determines that the first condition is satisfied when the heart rate or blood flow rate rises by a predetermined value from the start of the application of the warming stimulus, and when the heart rate or blood flow rate falls by a predetermined value from the start of the application of the cooling stimulus.

[0020] According to the present invention configured in this way, after initially providing a cool or warm sensation to the bather, the warm or cool sensation is switched when the heart rate or blood flow rises or falls above a predetermined value from the start of the application of the warm or cool sensation. This allows for switching the sensation at an appropriate time, and enables the application of a warm or cool sensation that provides a fatigue-relieving effect to the bather.

[0021] In the present invention, preferably, the control unit determines that the first condition is satisfied when the heart rate or blood flow rate becomes greater than a predetermined upper threshold, and determines that the second condition is satisfied when the heart rate or blood flow rate becomes less than a predetermined lower threshold.

[0022] According to the present invention configured in this way, when the heart rate or blood flow rate exceeds a predetermined upper threshold or falls below a predetermined lower threshold, the warming and cooling stimuli are switched. This allows the stimuli to be switched at the appropriate time, providing the bather with a warming or cooling stimuli that can relieve fatigue.

[0023] In the present invention, preferably, the control unit determines that the first condition is satisfied when the rate of increase in heart rate or blood flow exceeds a predetermined rate of increase, and determines that the second condition is satisfied when the rate of decrease in heart rate or blood flow exceeds a predetermined rate of decrease.

[0024] According to the present invention configured in this way, when the rate of increase or decrease in heart rate or blood flow exceeds a predetermined value, the warming stimulus and the cooling stimulus are switched, so that the stimulus can be switched at an appropriate time, and a warming stimulus or a cooling stimulus that can give the bather a fatigue-relieving effect can be provided.

[0025] In the present invention, preferably, the bathtub body is further provided with a plurality of electrodes, and the biological information acquisition unit estimates the blood flow rate of the bather based on the electrocardiogram signals detected by the plurality of electrodes.

[0026] To ensure a comfortable bathing experience without disrupting the bather's bathing, it is desirable to measure blood flow non-contact. However, if an optical sensor is used for non-contact measurement, for example, the measurement position changes if the bather's posture or position shifts during bathing, resulting in poor measurement accuracy. According to the present invention configured as described above, the bather's blood flow is estimated based on the bather's electrocardiogram signal, regardless of the bather's posture or position during bathing, thus enabling the acquisition of the bather's blood flow without burdening the bather.

[0027] In the present invention, preferably, the system further includes an elapsed time detection unit for detecting the time elapsed since the bather entered the bathtub body, and a water temperature acquisition unit for acquiring the temperature of the water stored in the bathtub body. The biological information acquisition unit estimates the bather's heart rate or blood flow rate based on the elapsed time detected by the elapsed time detection unit and the water temperature acquired by the water temperature acquisition unit.

[0028] According to the present invention configured in this way, the bather's heart rate or blood flow rate can be estimated based on the elapsed time since the bather entered the bathtub and the temperature of the water stored in the bathtub. Therefore, the heart rate or blood flow rate can be easily estimated without the need for special sensors. [Effects of the Invention]

[0029] According to the bathtub device of the present invention, a sufficient fatigue recovery effect can be obtained regardless of individual differences among bathers or how they use the device. [Brief explanation of the drawing]

[0030] [Figure 1] This is a perspective view showing the entire bathroom with a bathtub device according to the first embodiment of the present invention installed. [Figure 2] This figure shows the hot water supply system to the water discharge device in a bathtub device according to the first embodiment of the present invention. [Figure 3] This is a cross-sectional view showing the structure of an electrode provided in a bathtub device according to the first embodiment of the present invention. [Figure 4] This is a block diagram of a control unit provided in a bathtub device according to the first embodiment of the present invention. [Figure 5] This figure shows an example of an electrocardiogram waveform of a bather acquired by a biological information acquisition unit provided in a bathtub device according to the first embodiment of the present invention. [Figure 6] This figure shows an example of the relationship between heart rate and blood flow. [Figure 7] This graph shows an example of the relationship between a bather's heart rate and their core body temperature. [Figure 8] This flowchart shows the operation of the bathtub device according to the first embodiment of the present invention. [Figure 9] This is a time chart showing an example of the operation of a bathtub device according to the first embodiment of the present invention. [Figure 10] This flowchart shows the operation of a bathtub device according to a second embodiment of the present invention. [Figure 11] This is a time chart showing an example of the operation of a bathtub device according to a second embodiment of the present invention. [Figure 12] This graph shows an example of the temporal change in blood flow of a bather immersed in water at a predetermined temperature stored in the bathtub. [Modes for carrying out the invention]

[0031] Next, a bathtub apparatus according to an embodiment of the present invention will be described with reference to the attached drawings. Figure 1 is a perspective view showing the entire bathroom with a bathtub device according to the first embodiment of the present invention installed. Figure 2 is a diagram showing the hot and cold water supply system to the water discharge device in the bathtub device according to the first embodiment of the present invention. Figure 3 is a cross-sectional view showing the structure of the electrodes provided in the bathtub device according to the first embodiment of the present invention. Figure 4 is a block diagram of the control unit provided in the bathtub device according to the first embodiment of the present invention.

[0032] As shown in Figure 1, the bathtub device 1 of the first embodiment of the present invention comprises a bathtub body 2, a negative electrode 4a, a positive electrode 4b, and a reference electrode 4c attached to the bathtub body 2, and is installed in a bathroom R. Furthermore, the bathtub device 1 comprises a water discharge device 8 provided on the upper edge of the bathtub body 2, a circulation device 9 that discharges hot water from the bathtub body 2 through the water discharge device 8 and the bathtub water outlet 9a, and a control unit 6 that controls the circulation device 9, etc. A remote control 6a is also attached to the wall of the bathroom R, and the water discharge device 8 of the bathtub device 1 can be operated by this remote control 6a. Furthermore, in this embodiment, the bathtub device 1 is arranged on one side of the bathroom R so as to be in contact with the wall.

[0033] In this embodiment, the bathtub device 1 is configured such that when a bather operates the water discharge device 8, water that is hotter or colder than the water stored in the bathtub body 2 is discharged from the water discharge device 8. Furthermore, in this embodiment, the bathtub device 1 is configured to control the temperature of the water discharged from the water discharge device 8 based on electrocardiogram signals acquired by the negative electrode 4a, positive electrode 4b, and reference electrode 4c, thereby providing the bather with a cooling or warming sensation.

[0034] The bathtub body 2 is formed in a roughly rectangular box shape in plan view and is configured to store hot water inside. In this embodiment, the bathtub body 2 is positioned so that one of its long sides and the two short sides on either side are in contact with the inner wall surface of the bathroom R. Furthermore, the inner wall surface constituting one of the short sides of the bathtub body 2 is configured as a backrest surface 2a, which is a first inner wall surface formed for the bather to lean against. In addition, a drain (not shown) for draining the hot water inside the bathtub body 2 is provided on the bottom surface of the bathtub body 2. Furthermore, an apron 2b is detachably attached to the long side of the bathtub body 2 on the side that is not in contact with the inner wall surface of the bathroom R.

[0035] The water discharge device 8 is installed on the upper part of the backrest surface 2a of the bathtub body 2 and is configured to discharge hot water inward into the bathtub body 2. In this embodiment, the water discharge device 8 has a flat, wide spout 8a that extends along the upper edge of the backrest surface 2a and is configured to discharge hot water towards the neck, shoulders, and back of a bather leaning against the backrest surface 2a. The water discharge device 8 is also configured to discharge a portion of the hot water drawn in from the bathtub water intake 9b by the circulation device 9 from the spout 8a. As a result, the hot water in the bathtub body 2 is drawn in by the circulation device 9 and circulated so that it is discharged from the spout 8a and flows back into the bathtub body 2. Furthermore, a portion of the hot water drawn in from the bathtub water intake 9b by the circulation device 9 is also discharged from the bathtub spout 9a provided on the backrest surface 2a of the bathtub body 2.

[0036] The negative electrode 4a and positive electrode 4b are a pair of electrodes attached to the bathtub body 2 to detect the bather's electrocardiogram signal via the water stored inside the bathtub body 2. The bather's electrocardiogram signal is acquired as a potential difference signal between these negative electrode 4a and positive electrode 4b. The pair of electrodes, consisting of the negative electrode 4a and positive electrode 4b, are both positioned on the backrest surface 2a, which forms part of the short side of the bathtub body 2. In addition, the reference electrode 4c is an electrode for acquiring a reference potential of the potential detected by the negative electrode 4a and positive electrode 4b, and this electrode is also positioned on the backrest surface 2a of the bathtub body 2.

[0037] Furthermore, the negative electrode 4a and the positive electrode 4b are positioned symmetrically with respect to the center line in the horizontal direction (width direction) of the backrest surface 2a. That is, the negative electrode 4a and the positive electrode 4b are positioned on the backrest surface 2a, spaced apart from the center line in the left and right directions. In addition, the negative electrode 4a and the positive electrode 4b are positioned below the water surface in the bathtub body 2. The negative electrode 4a and the positive electrode 4b are below the water surface in the bathtub body 2 and can be installed at a height above the reference electrode 4c. On the other hand, the reference electrode 4c is positioned on the center line of the backrest surface 2a, below the negative electrode 4a and the positive electrode 4b. Furthermore, the reference electrode 4c is not necessarily required and can be omitted.

[0038] Next, with reference to Figure 2, the hot and cold water supply system to the water discharge device 8 will be explained. First, as shown in Figure 2, the circulation device 9 is configured to draw in hot water from the bathtub body 2 through a bathtub water intake port 9b provided on the inner wall surface of the bathtub body 2, and to discharge the hot water into the bathtub body 2 through a discharge port 8a of the discharge device 8. In addition, a portion of the hot water drawn in through the bathtub water intake port 9b is discharged through a bathtub discharge port 9a provided on the backrest surface 2a of the bathtub body 2. Specifically, the circulation device 9 is composed of a pump that draws in hot water from the bathtub water intake port 9b and discharges it through the discharge port 8a and the bathtub discharge port 9a.

[0039] Meanwhile, the water discharge device 8 is also supplied with hot water and cold water from a high-temperature hot water supply pipe 40a that supplies hot water at a higher temperature than the hot water stored in the bathtub body 2, and from a low-temperature hot water supply pipe 40b that supplies cold water at a lower temperature than the hot water stored in the bathtub body 2. That is, the hot water drawn in from the bathtub intake 9b and pressurized by the circulation device 9, the hot water supplied from the high-temperature hot water supply pipe 40a, and the cold water supplied from the low-temperature hot water supply pipe 40b are all led to the mixing chamber 44, where they are mixed and discharged from the discharge port 8a of the water discharge device 8. It should be noted that the hot water from the high-temperature hot water supply pipe 40a and the cold water from the low-temperature hot water supply pipe 40b can also be merged and mixed in the pipeline without providing a special mixing chamber with a large volume.

[0040] Furthermore, the high-temperature hot water supply pipe 40a and the low-temperature hot water supply pipe 40b are connected to the mixing chamber 44 via the high-temperature side linear valve 42a and the low-temperature side linear valve 42b, respectively, allowing control of the amount of hot water or cold water flowing into the mixing chamber 44 from each supply pipe. In addition, in this embodiment, the high-temperature hot water supply pipe 40a is supplied with hot water at a temperature higher than the temperature of the hot water stored in the bathtub body 2 from the water heater 52. That is, the tap water supplied from the water supply 54 is branched at the branching section 54a, with one branch supplied to the water heater 52 and the other flowing directly into the low-temperature hot water supply pipe 40b. The tap water supplied to the water heater 52 is heated to a temperature higher than the temperature of the hot water stored in the bathtub body 2 and supplied to the high-temperature hot water supply pipe 40a.

[0041] As a result, when discharging water at a temperature higher than the water stored in the bathtub body 2, the high-temperature linear valve 42a opens, and the water drawn in from the bathtub body 2 and the water supplied from the high-temperature water supply pipe 40a are mixed in the mixing chamber 44 and discharged from the water discharge device 8. On the other hand, when discharging water at a temperature lower than the water stored in the bathtub body 2, the low-temperature linear valve 42b opens, and the water drawn in from the bathtub body 2 and the tap water supplied from the low-temperature water supply pipe 40b are mixed in the mixing chamber 44 and discharged from the water discharge device 8. Therefore, in this embodiment, the high-temperature linear valve 42a, the low-temperature linear valve 42b, the circulation device 9, and the water discharge device 8 function as a hot and cold device that provides bathers with hot and cold sensations.

[0042] Furthermore, the temperature of the water stored in the bathtub body 2 is detected by a bathtub temperature sensor 46 attached to the bathtub body 2. The temperature of the water to be discharged from the water discharge device 8 is detected by a water discharge temperature sensor 48 attached to the water discharge device 8. Furthermore, the temperature of the water flowing in from the high-temperature water supply pipe 40a is detected by the high-temperature side temperature sensor 50a, and the temperature of the water flowing in from the low-temperature water supply pipe is detected by the low-temperature side temperature sensor 50b. In addition, some sensors for detecting the temperature of each water and the water can be omitted by estimating the temperature based on data obtained from other sensors.

[0043] The temperatures detected by these temperature sensors are sent to the control unit 6, which controls the opening of the high-temperature linear valve 42a and the low-temperature linear valve 42b based on these detected temperatures, causing hot water at the required temperature to be discharged from the water discharge device 8. In other words, the control unit 6 controls the opening of the high-temperature linear valve 42a and the low-temperature linear valve 42b so that the temperature detected by the water discharge temperature sensor 48 is the required temperature. Details of the control by the control unit 6 will be described later.

[0044] Next, with reference to Figure 3, the structure of each electrode attached to the bathtub body 2 will be explained. In this description, the structure of the negative electrode 4a is explained, but in this embodiment, the negative electrode 4a, the positive electrode 4b, and the reference electrode 4c all have the same structure.

[0045] As shown in Figure 3, the negative electrode 4a includes an electrode portion 10, a front packing 12a, a back packing 12b, a flange 14, a moisture-proof tube 16, a connection terminal 18, a fixing screw 20, a conductor 22, and a sheath 24. The negative electrode 4a is mounted so as to be exposed on the surface of the backrest surface 2a of the bathtub body 2, and watertightness between the negative electrode 4a and the backrest surface 2a is ensured by the packing.

[0046] The electrode portion 10 is a conductive metal component and consists of a disc-shaped disc portion 10a and a shaft portion 10b that protrudes vertically from the back surface of the disc portion 10a. The disc portion 10a is a thin disc-shaped part, and its front surface is exposed to the surface of the backrest surface 2a, configured to detect electric potential. In this embodiment, the disc portion 10a is formed to have a diameter of approximately 15 mm and a thickness of approximately 2.5 mm, and the entire disc portion 10a is placed on the surface of the backrest surface 2a. The shaft portion 10b is a round rod-shaped part that extends perpendicularly from the center of the back surface of the disc portion 10a, and protrudes to the back side of the backrest surface 2a through a through hole formed in the backrest surface 2a. Furthermore, a male screw thread is formed in the middle part of the shaft portion 10b, and a fixing part for fixing the connection terminal 18 is formed at the tip.

[0047] The front packing 12a is a disc-shaped component made of rubber, with a circular hole formed in the center for the shaft portion 10b of the electrode portion 10 to pass through. The front packing 12a has approximately the same diameter as the disc portion 10a of the electrode portion 10 and is positioned on the back side of the disc portion 10a. When the negative electrode 4a is attached to the backrest surface 2a, the front packing 12a is sandwiched between the back surface of the disc portion 10a and the surface of the backrest surface 2a, ensuring watertightness between the backrest surface 2a and the negative electrode 4a.

[0048] The rear packing 12b is a disc-shaped component made of rubber, with a circular hole formed in the center for the shaft portion 10b of the electrode portion 10 to pass through. The rear packing 12b is larger than the front packing 12a and has approximately the same diameter as the large-diameter portion of the flange 14, and is positioned on the rear side of the backrest surface 2a. When the negative electrode 4a is attached to the backrest surface 2a, the rear packing 12b is sandwiched between the back surface of the backrest surface 2a and the end face of the flange 14, ensuring watertightness between the back surface of the backrest surface 2a and the negative electrode 4a. The front packing 12a and rear packing 12b may be made of resin.

[0049] The flange 14 is a stepped cylindrical member consisting of a large-diameter section and a small-diameter section, and has a female screw thread in its center for the shaft section 10b of the electrode section 10 to pass through. The large-diameter section of the flange 14 is formed to have approximately the same diameter as the back packing 12b, and the small-diameter section is formed on the back side of the large-diameter section. By screwing the female screw thread formed to pass through the flange 14 into the male screw thread formed on the shaft section 10b of the electrode section 10 and tightening it, the end face on the large-diameter side of the flange 14 presses the back packing 12b against the back surface of the backrest surface 2a, ensuring watertightness.

[0050] The moisture-proof tube 16 is a long, slender rubber tube positioned to cover the tip of the shaft portion 10b of the electrode portion 10, the connection terminal 18, the conductor 22, etc. A small-diameter flange 14 is fitted to the tip of the moisture-proof tube 16 to prevent moisture from entering the moisture-proof tube 16. The moisture-proof tube 16 may also be made of resin.

[0051] The connector terminal 18 is a component made of conductive metal and is crimped to the end of the conductor 22. The tip of the connector terminal 18 has a hole for passing a fixing screw 20 through. By screwing the fixing screw 20 through this hole into a female thread provided at the tip of the shaft portion 10b of the electrode portion 10, the connector terminal 18 can be fixed to the electrode portion 10. This allows the electrode portion 10 and the conductor 22 to be electrically connected in a detachable manner.

[0052] The conductor 22 is a conductive wire for electrically connecting the electrode section 10 and the control unit 6 (Figure 1), and extends from the negative electrode 4a to the control unit 6. Furthermore, the conductor 22 is covered with a sheath 24 made of insulating material to ensure its electrical insulation. In this embodiment, the conductors 22 extending from the negative electrode 4a, the positive electrode 4b, and the reference electrode 4c are connected to the control unit 6, and the electrocardiogram signal is input to the control unit 6.

[0053] Next, with reference to Figure 4, the configuration of the control unit 6 provided in the bathtub device 1 according to the first embodiment of the present invention will be described. As shown in Figure 4, the control unit 6 includes a biometric information acquisition unit 56 that estimates the blood flow rate of the bather, a body temperature acquisition unit 58 that acquires the body temperature of the bather, an elapsed time detection unit 60 that detects the elapsed time after entering the bathtub, a water temperature acquisition unit 62 that acquires the temperature of the water in the bathtub body 2, and a control unit 64 that controls the heating and cooling device. Specifically, the control unit 6 is composed of a microprocessor, memory, interface circuitry, and software to operate these (not shown), and realizes the functions of each of the above-mentioned parts.

[0054] As shown in Figure 4, the control unit 6 is connected to a negative electrode 4a, a positive electrode 4b, and a reference electrode 4c, and the potential information acquired by these electrodes is input to the control unit 6. Furthermore, the control unit 6 is connected to a bathtub temperature sensor 46, a water outlet temperature sensor 48, a high-temperature side temperature sensor 50a, and a low-temperature side temperature sensor 50b, and the detection signals from these sensors are input to the control unit 6. In addition, the control unit 6 is connected to a circulation device 9, a high-temperature side linear valve 42a, and a low-temperature side linear valve 42b, and these are operated by control signals from the control unit 6.

[0055] The biological information acquisition unit 56 is configured to detect the bather's electrocardiogram signal based on the potential signals acquired by the negative electrode 4a, the positive electrode 4b, and the reference electrode 4c. The bather's electrocardiogram signal inside the bathtub body 2 can be detected as a potential difference signal between each electrode via the water inside the bathtub body 2.

[0056] Figure 5 shows an example of an electrocardiogram (ECG) waveform of a bather acquired by the biometric information acquisition unit 56. The ECG signal is acquired by the biometric information acquisition unit 56 as a potential difference signal between the negative electrode 4a and the positive electrode 4b, and the ECG waveform shown in Figure 5 is this signal shown as a time-series waveform. As shown in Figure 5, large-amplitude impulse-like R waves appear periodically in the ECG waveform, and the bather's heart rate (bpm) can be obtained by counting the number of R waves per unit time. Furthermore, the biometric information acquisition unit 56 is configured to estimate the bather's blood flow rate based on the heart rate obtained from the ECG signal.

[0057] Figure 6 shows an example of the relationship between heart rate and blood flow rate. The upper section of Figure 6 is a graph showing an example of the change in the bather's heart rate (bpm) over time in the bathtub body 2. The middle section of Figure 6 is a graph showing an example of the change in the bather's blood flow rate (mL / min / 100g) over time, measured simultaneously with the heart rate shown in the upper section. As shown in Figure 6, it can be seen that the bather's blood flow rate increases with increasing heart rate. Furthermore, the lower section of Figure 6 shows the correlation between the heart rate shown in the upper section and the blood flow rate shown in the middle section. Thus, there is a sufficiently high correlation between the bather's heart rate and blood flow rate, and by detecting the bather's heart rate, the blood flow rate can be estimated with sufficient accuracy. In this embodiment, the biological information acquisition unit 56 uses this correlation to estimate the bather's blood flow rate based on the electrocardiogram signal. As a modification, the present invention can also be configured to directly detect the bather's blood flow rate by equipping the bathtub device 1 with a laser blood flow meter or the like.

[0058] Next, the body temperature acquisition unit 58 is configured to acquire the body temperature of the bather inside the bathtub body 2. In this embodiment, the body temperature acquisition unit 58 is configured to estimate the bather's core body temperature as the bather's body temperature based on the bather's heart rate acquired by the biological information acquisition unit 56. Here, core body temperature refers to the temperature inside the bather's body, and is usually measured as sublingual temperature, rectal temperature, tympanic temperature, etc. Figure 7 is a graph showing an example of the relationship between the bather's heart rate and the bather's core body temperature. In this embodiment, the body temperature acquisition unit 58 estimates the bather's core body temperature based on the relationship between heart rate and core body temperature as shown in Figure 7.

[0059] In this embodiment, the body temperature acquisition unit 58 estimates the change in the bather's core body temperature based on the change in the bather's heart rate. However, the present invention can also be configured to directly measure the bather's body temperature. For example, the bather can be imaged using a thermograph (not shown) to detect their body temperature. Although the body temperature detected by the thermograph is the bather's surface temperature, a predetermined relationship between surface temperature and core body temperature is known, so the core body temperature can be estimated from the detected surface temperature. Alternatively, the present invention can be configured so that the bather's body temperature is measured by having them wear a thermometer while bathing.

[0060] Next, the elapsed time detection unit 60 is configured to detect the time elapsed after the bather has immersed themselves in the bathwater in the bathtub body 2. Specifically, when the bather enters the bathtub body 2, the biometric information acquisition unit 56 begins to acquire the bather's electrocardiogram signal. When the biometric information acquisition unit 56 begins to acquire the electrocardiogram signal, the elapsed time detection unit 60 determines that the bather has entered the bathtub body 2 and accumulates the elapsed time from this point using a timer (not shown) built into the control unit 6. It should be noted that the present invention can also be configured to include an arbitrary sensor capable of detecting when the bather has entered the bathtub body 2, and to use this sensor to detect the bather's entry and measure the elapsed time after detection.

[0061] The water temperature acquisition unit 62 is configured to acquire the temperature of each part based on detection signals input from the bathtub temperature sensor 46, the water outlet temperature sensor 48, the high-temperature side temperature sensor 50a, and the low-temperature side temperature sensor 50b. Specifically, the water temperature acquisition unit 62 acquires the temperature of the water stored in the bathtub body 2 based on the detection signal input from the bathtub temperature sensor 46. In this embodiment, the temperature of the water in the bathtub body 2 acquired by the water temperature acquisition unit 62 is used as the reference temperature, and water with a temperature higher than the reference temperature is discharged from the water outlet device 8 as a warming stimulus, while water with a temperature lower than the reference temperature is discharged from the water outlet device 8 as a cooling stimulus.

[0062] Furthermore, the water temperature acquisition unit 62 acquires the temperature of the hot water supplied from the high-temperature water supply pipe 40a based on a detection signal input from the high-temperature side temperature sensor 50a, and acquires the temperature of the water supplied from the low-temperature water supply pipe 40b based on a detection signal input from the low-temperature side temperature sensor 50b. The water temperature acquisition unit 62 also acquires the temperature of the hot water discharged from the water discharge device 8 based on a detection signal input from the water discharge temperature sensor 48. In this embodiment, temperature sensors are provided for acquiring the temperature of each part, but the present invention can be configured so that at least some of these temperature sensors are omitted and the water temperature acquisition unit 62 acquires the estimated temperature. For example, if the temperature of the water in the bathtub body 2 is maintained at a certain set temperature by a temperature control device (not shown), the present invention can be configured so that this set temperature is acquired by the water temperature acquisition unit 62 as the temperature of the water in the bathtub body 2.

[0063] The control unit 64 is configured to provide the bather with either a warm or cool sensation based on the bather's blood flow rate estimated by the biological information acquisition unit 56. When providing a warm sensation, the control unit 64 activates the circulation device 9 to discharge the water from the bathtub body 2, which has been taken in through the bathtub water intake 9b, from the outlet 8a of the water discharge device 8. At the same time, it opens the high-temperature side linear valve 42a to mix hotter water with the water discharged from the outlet 8a. As a result, water hotter than the standard temperature of the water in the bathtub body 2 is discharged from the outlet 8a of the water discharge device 8, providing the bather with a warm sensation. On the other hand, when providing a cool sensation, the control unit 64 discharges the water from the bathtub body 2 from the outlet 8a of the water discharge device 8, and also opens the low-temperature side linear valve 42b to mix colder water with the water discharged from the outlet 8a. As a result, water at a lower temperature than the standard temperature of the water in the bathtub body 2 is discharged from the spout 8a of the water dispensing device 8, providing a cooling sensation to the bather.

[0064] Therefore, in this embodiment, the water discharge device 8, the circulation device 9, the high-temperature side linear valve 42a, and the low-temperature side linear valve 42b function as a hot and cold device that provides the bather with a hot sensation higher than a predetermined reference temperature and a cold sensation lower than a predetermined reference temperature. Further details of the control by the control unit 64 will be described later.

[0065] Next, the operation of the bathtub device 1 according to the first embodiment of the present invention will be described with reference to Figures 8 and 9. Figure 8 is a flowchart showing the operation of the bathtub device 1 of this embodiment. Figure 9 is a time chart showing an example of the operation of the bathtub device 1 of this embodiment. Note that the flowchart shown in Figure 8 is executed when the bather enters the bathtub body 2, that is, when the biometric information acquisition unit 56 built into the control unit 6 begins to detect the bather's electrocardiogram signal.

[0066] First, in step S1 of Figure 8, it is determined whether a predetermined waiting time has elapsed after the bather has entered the bathtub body 2. The process in step S1 is carried out after the predetermined waiting time t W This process is repeated until a predetermined waiting time t has elapsed. That is, it is known that the bather's heart rate and blood flow temporarily increase due to the "startle reflex" immediately after entering the bathtub 2. The increased heart rate and blood flow due to this startle reflex do not represent the bather's actual physical state. For this reason, in this embodiment, a predetermined waiting time t W After the waiting time t has elapsed, the system is configured to start applying a cooling or warming stimulus to the bather based on the blood flow rate acquired by the biological information acquisition unit 56. W It is set to 1 minute.

[0067] Figure 9 is a time chart showing an example of the operation of the bathtub device 1. The upper section shows the temporal change in the blood flow rate of the bather, and the lower section shows the temperature of the water discharged from the water discharge device 8. In the example shown in FIG. 9, when the bather immerses in the hot water in the bathtub main body 2 at time t0, the bather's heart rate increases due to the startle reflex, and accordingly, the blood flow volume of the bather also increases. Then, at time t1 when the waiting time t W has elapsed, the increase in blood flow volume due to the startle reflex also subsides, and the blood flow volume has decreased to a value close to that of the bather's normal state.

[0068] When the waiting time t w has elapsed, the process in the flowchart of FIG. 8 proceeds to step S2. In step S2, it is determined whether or not the bather's body temperature has risen above a predetermined body temperature T1. That is, the control unit 64 determines whether or not the deep body temperature of the bather estimated by the body temperature acquisition unit 58 has risen above the predetermined body temperature T1. If it has risen above the body temperature T1, the process proceeds to step S4, and if it has not risen above the body temperature T1, the process proceeds to step S3. That is, when the deep body temperature of the bather has risen sufficiently, the process proceeds to the process of applying a warm sensation stimulus or a cool sensation stimulus in step S4 and below. On the other hand, when the deep body temperature of the bather has not risen sufficiently, the process proceeds to step S3, and after the waiting time t W has elapsed, the process of step S3 is repeated until a predetermined extension time t E has elapsed.

[0069] In this embodiment, the predetermined body temperature T1 is set to 37.5°C, and the predetermined extension time t E is set to 3 minutes. That is, if the process proceeds to the process of applying a warm sensation stimulus or a cool sensation stimulus in a state where the deep body temperature of the bather has not risen sufficiently, the bather may not be able to enjoy the bath and may be given discomfort. Therefore, in this embodiment, after the bather's body has warmed sufficiently, a warm sensation stimulus or a cool sensation stimulus is applied, and when the body has not warmed sufficiently, the waiting time t W for the bather to warm up is extended by a predetermined extension time t E as described above. Thus, in this embodiment, the control unit 64 changes the waiting time t W based on the body temperature of the bather acquired by the body temperature acquisition unit 58.

[0070] In the example shown in Figure 9, after bathing begins at time t0, a predetermined waiting period t W Since the bather's body temperature is at a suitable temperature at time t1, the process in the flowchart of Figure 8 proceeds to step S4 at time t1.

[0071] In step S4, the discharge of hot and cold water from the outlet 8a of the water discharge device 8 begins. That is, the control unit 64 of the control unit 6 sends a control signal to the circulation device 9 to activate it and discharge hot and cold water from the water discharge device 8. In this state, the high-temperature side linear valve 42a and the low-temperature side linear valve 42b remain closed. Therefore, the hot and cold water in the bathtub body 2 that is drawn in from the bathtub water intake 9b (Figure 2) is discharged directly from the outlet 8a of the water discharge device 8 and directed onto the bather's neck and shoulders. Thus, in this embodiment, after the bather starts bathing, a predetermined waiting time t W After a certain period of time has elapsed and the bather's body temperature has reached a suitable temperature, the discharge of hot and cold water from the water dispensing device 8 begins. In contrast, as a variation, the discharge begins immediately after the start of bathing, or after a waiting period t W The present invention can also be configured such that the discharge of hot and cold water from the water discharge device 8 is initiated.

[0072] Next, in step S5, the heart rate is determined from the detected electrocardiogram signal of the bather, and the bather's blood flow is estimated based on this. The estimated blood flow is acquired by the biological information acquisition unit 56 of the control unit 6.

[0073] Furthermore, in step S6, it is determined whether the increase in blood flow rate obtained by the biological information acquisition unit 56 satisfies a predetermined first condition. That is, when the discharge of hot water from the water discharge device 8 begins at time t1 in Figure 9, the heart rate, blood flow rate, and core body temperature of the bather being bathed in it begin to rise. In step S6, a predetermined waiting time t WAfter a certain period of time has elapsed, the blood flow rate at time t1, when the discharge of hot and cold water from the water discharge device 8 begins, is used as the reference point. When the blood flow rate rises from this reference point by a predetermined value, the first condition is determined to be satisfied. In this embodiment, if it is estimated that the blood flow rate has increased by 3 (mL / min / 100g) from the blood flow rate at the reference point, the first condition is determined to be satisfied. In the flowchart shown in Figure 8, after time t1, the process of steps S5→S6→S7→S8→S5 is repeatedly executed until the first condition is satisfied.

[0074] Thus, in this embodiment, when the bather is initially given a cooling or warming sensation, a predetermined waiting period t is given after the bather enters the bathtub body 2. W The blood flow rate after a certain period of time is used as a baseline, and when the first differential value increases from this baseline, it is determined that the first condition has been met. W If the second differential value decreases from the blood flow rate after a certain period of time has elapsed, the control unit 64 determines that the second condition has been met.

[0075] Furthermore, as a modified version, the present invention can be configured such that the first condition is determined to be satisfied when the blood flow rate rises by a predetermined first differential value from the reference point, i.e., immediately after the start of bathing, based on the timing at which the biological information acquisition unit 56 acquires the blood flow value. In this modified version, the control unit 64 determines that the second condition is satisfied when the blood flow rate falls by a second differential value from the reference point, based on immediately after the start of bathing.

[0076] Next, at time t2 in Figure 9, if the blood flow rate of the bather increases by a predetermined first difference value from the blood flow rate at the reference point, the process in the flowchart shown in Figure 8 proceeds to step S6 → S9.

[0077] In step S9, the control unit 64 performs the application of a cooling sensation. Specifically, the control unit 64 of the control unit 6 sends a control signal to the low-temperature linear valve 42b, causing it to open by a predetermined amount. As a result, the water in the bathtub body 2, which is drawn in from the bathtub water intake 9b (Figure 2) and discharged from the outlet 8a of the water discharge device 8, is mixed with the low-temperature water supplied from the low-temperature water supply pipe 40b, and the temperature of the water discharged from the outlet 8a decreases. This causes the bather's neck and shoulders to be exposed to the low-temperature water, providing them with a cooling sensation. In this embodiment, the control unit 64 controls the opening of the low-temperature linear valve 42b so that water approximately 4°C lower than the reference temperature of the water in the bathtub body 2 is discharged from the outlet 8a of the water discharge device 8.

[0078] In the example shown in Figure 9, the low-temperature linear valve 42b is opened at time t2, and as shown in the lower part of Figure 9, the temperature of the hot water discharged from the outlet 8a decreases. At this time, the opening degree of the low-temperature linear valve 42b is gradually increased so that the temperature of the discharged hot water does not drop too rapidly.

[0079] In this way, by applying a cooling sensation to the bather, the bather's heart rate, blood flow, and core body temperature begin to decrease. In the example shown in Figure 9, as shown in the upper section, the bather's blood flow begins to decrease, with the blood flow at time t2 as the reference point. In the flowchart shown in Figure 8, after step S9 is executed at time t2, the processes of steps S8→S5→S6→S7→S8 are repeatedly executed.

[0080] In step S7, it is determined whether the decrease in blood flow obtained by the biological information acquisition unit 56 satisfies a predetermined second condition. That is, when the cooling stimulus is started at time t2 in Figure 9, the bather's heart rate, blood flow, and core body temperature begin to decrease. In step S7, the blood flow at time t2 when the cooling stimulus was started is used as a reference point, and when the blood flow decreases from this reference point by a predetermined second difference value, it is determined that the second condition has been satisfied. In this embodiment, if it is estimated that the blood flow has decreased by 2 (mL / min / 100g) from the blood flow at the reference point, it is determined that the second condition has been satisfied.

[0081] Thus, in this embodiment, after the bather is initially given a cooling or warming stimulus, the control unit 64 determines that the second condition is satisfied when the blood flow rate decreases by a predetermined value from the start of the cooling stimulus. Furthermore, in this embodiment, after the bather is initially given a cooling or warming stimulus, the control unit 64 determines that the first condition is satisfied when the blood flow rate increases by a predetermined value from the start of the warming stimulus.

[0082] Next, at time t3 in Figure 9, if the blood flow rate of the bather decreases by a predetermined second difference value from the blood flow rate at the reference point, the process in the flowchart shown in Figure 8 proceeds to step S7 → S10.

[0083] In step S10, the control unit 64 applies a thermal stimulus. Specifically, the control unit 64 of the control unit 6 sends a control signal to the low-temperature linear valve 42b to close it, while simultaneously sending a control signal to the high-temperature linear valve 42a to open it by a predetermined amount. As a result, the hot water supplied from the high-temperature hot water supply pipe 40a is mixed with the hot water in the bathtub body 2, which is drawn in from the bathtub water intake 9b (Figure 2) and discharged from the discharge port 8a of the water discharge device 8, causing the temperature of the hot water discharged from the discharge port 8a to rise. This causes the hot water to be applied to the bather's neck and shoulders, providing a thermal stimulus to the bather. In this embodiment, the control unit 64 controls the opening of the high-temperature linear valve 42a so that the hot water discharged from the discharge port 8a of the water discharge device 8 is approximately 2°C higher than the reference temperature of the hot water in the bathtub body 2.

[0084] In the example shown in Figure 9, the high-temperature linear valve 42a is opened at time t3, and as shown in the lower part of Figure 9, the temperature of the hot water discharged from the outlet 8a rises. At this time, the opening degree of the high-temperature linear valve 42a is gradually increased so that the temperature of the discharged hot water does not rise too rapidly.

[0085] In this way, by applying a thermal stimulus to the bather, the bather's heart rate, blood flow, and core body temperature begin to rise. In the example shown in Figure 9, as shown in the upper section, the bather's blood flow begins to rise, with the blood flow at time t3 as the reference point. In the flowchart shown in Figure 8, after step S10 is executed at time t3, the processes of steps S8→S5→S6→S7→S8 are repeatedly executed.

[0086] Subsequently, in the example shown in Figure 9, at time t4, when the blood flow increases to a predetermined value (the first differential value), it is determined that the first condition has been satisfied again, and the application of the cooling stimulus is initiated. Thereafter, the application of the cooling stimulus and the application of the warming stimulus are repeated alternately, and the bather's blood flow decreases and increases repeatedly as a result. In this way, the bather's circulation improves due to the repeated increases and decreases in blood flow, and the fatigue substances accumulated in the body decrease. Furthermore, the reduction in fatigue substances lowers muscle stiffness, and the bather's fatigue is relieved.

[0087] After time t4, when the bather has recovered from fatigue and leaves the bath (gets out of the bathtub 2), the biometric information acquisition unit 56 of the control unit 6 no longer detects an electrocardiogram signal, and it is determined that the bather has left the bath. When the bather leaves the bath, the process in the flowchart of Figure 8 proceeds to step S8 → END, and one cycle of the process shown in the flowchart of Figure 8 is completed.

[0088] According to the bathtub device 1 of the first embodiment of the present invention, a cooling sensation is provided to the bather based on an increase in blood flow (steps S6 to S9 in Figure 8), and a warming sensation is provided to the bather based on a decrease in blood flow (steps S7 to S10 in Figure 8). As a result, it is possible to reliably provide the bather with stimuli that increase and decrease blood flow, and a sufficient fatigue recovery effect can be obtained regardless of individual differences among bathers or how the bather uses the device.

[0089] Furthermore, according to the bathtub device 1 of this embodiment, after the bather enters the bathtub body 2, a predetermined waiting time t W After the process (steps S1 to S2 in Figure 8), the circulation device 9, which is a heating and cooling device, is controlled based on the blood flow rate acquired by the biological information acquisition unit 56. As a result, a cooling or warming stimulus can be applied based on a highly reliable blood flow rate that accurately reflects the physical condition of the bather, thereby ensuring a fatigue recovery effect.

[0090] Furthermore, according to the bathtub device 1 of this embodiment, the waiting time is changed based on the bather's body temperature (steps S2→S5 or S2→S3→S5 in Figure 8), so that a cooling or warming stimulus can be applied after the bather's body temperature reaches an appropriate temperature, allowing the bather to enjoy a comfortable bath and also obtain the fatigue-relieving effect of the cooling or warming stimulus.

[0091] Furthermore, according to the bathtub device 1 of this embodiment, the bather's body temperature is estimated based on the bather's heart rate (Figure 7), so the bather's body temperature can be obtained without placing any burden on the bather.

[0092] Furthermore, according to the bathtub device 1 of this embodiment, when the blood flow rate rises (from t3 to t4 in Figure 9) or falls (from t2 to t3 in Figure 9) above a predetermined value from the start of applying the warming or cooling stimulation, the warming and cooling stimulation can be switched at an appropriate time, and the bather can be provided with warming or cooling stimulation that has a fatigue-relieving effect.

[0093] Furthermore, according to the bathtub device 1 of this embodiment, the bather's blood flow rate is estimated based on the bather's electrocardiogram signal (Figure 6), so the bather's blood flow rate can be obtained without placing any burden on the bather.

[0094] Next, a bathtub apparatus according to a second embodiment of the present invention will be described with reference to Figures 10 and 11. The bathtub device of this embodiment differs from the first embodiment described above in that the control performed by the control unit 6 is different. Therefore, only the parts of the second embodiment of the present invention that differ from the first embodiment will be described here, and similar configurations, operations, and effects will not be described.

[0095] Figure 10 is a flowchart showing the operation of the bathtub device of this embodiment. Figure 11 is a time chart showing an example of the operation of the bathtub device of this embodiment. Note that, as with the first embodiment described above, the flowchart shown in Figure 10 starts executing when the bather enters the bathtub body 2.

[0096] First, the processes in steps S11 to S15 in Figure 10 are the same as the processes in steps S1 to S5 in Figure 8, so we will omit the explanation. Also, in the time chart shown as an example in Figure 11, time t 10 When a bather immerses themselves in the water inside the bathtub 2, the startle reflex causes the bather's heart rate and blood flow to increase, and during the waiting period t W The elapsed time t 11 At this point, blood flow decreases to a value close to that of the bather's normal state. Then, at time t 11 In this step, the bather's core body temperature has risen to a predetermined temperature T1 or higher, so the discharge of hot water from the outlet 8a of the water discharge device 8 begins. That is, the hot water in the bathtub body 2, which has been drawn in from the bathtub water intake 9b (Figure 2), is discharged directly from the outlet 8a of the water discharge device 8 and applied to the bather's neck and shoulders. Furthermore, in step S15 of Figure 10, the heart rate is determined from the detected electrocardiogram signal of the bather, and the bather's blood flow rate is estimated based on this. The estimated blood flow rate is acquired by the biological information acquisition unit 56 of the control unit 6.

[0097] Next, in step S16, it is determined whether the blood flow rate acquired by the biological information acquisition unit 56 satisfies a predetermined first condition. That is, at time t in Figure 11 11 When the discharge of hot water from the water discharge device 8 begins, the heart rate, blood flow rate, and core body temperature of the bather being bathed in it begin to rise. In step S16, when the rising blood flow rate exceeds a predetermined upper threshold, it is determined that the first condition has been satisfied. In this embodiment, when the blood flow rate exceeds 12 (mL / min / 100g), it is determined that the first condition has been satisfied. Preferably, this upper threshold for blood flow rate is set to 10-13 (mL / min / 100g). In the flowchart shown in Figure 10, time t 11 After that, the process of steps S15→S16→S17→S18→S15 is repeatedly executed until the first condition is satisfied.

[0098] Next, time t in Figure 11 12In this case, if the blood flow rate of the bather exceeds the upper threshold, the process in the flowchart shown in Figure 10 proceeds from step S16 to S19.

[0099] In step S19, the control unit 64 performs the application of a cooling sensation for a predetermined time. Specifically, the control unit 64 of the control unit 6 sends a control signal to the low-temperature linear valve 42b, causing it to open by a predetermined amount. As a result, the water in the bathtub body 2, which is drawn in from the bathtub water intake 9b (Figure 2) and discharged from the discharge port 8a of the water discharge device 8, is mixed with the low-temperature water supplied from the low-temperature water supply pipe 40b, and the temperature of the water discharged from the discharge port 8a decreases. As a result, the bather's neck and shoulders are exposed to the low-temperature water, providing a cooling sensation. In this embodiment, the control unit 64 controls the opening of the low-temperature linear valve 42b so that water approximately 4°C lower than the reference temperature of the water in the bathtub body 2 is discharged from the discharge port 8a of the water discharge device 8. In the time chart of Figure 11, time t 12 The system has been designed to provide a cooling sensation to bathers.

[0100] time t 12 After the application of the cooling sensation is initiated, a predetermined alternation time t a Once the time has elapsed, the process in the flowchart shown in Figure 10 proceeds to step S19 → S20. In this embodiment, the predetermined shift time t a It is set to approximately 2 minutes, and the time t 12 The cooling sensation that begins at [location] continues for approximately 2 minutes.

[0101] Next, in step S20, the control unit 64 controls the application of thermal stimulation for a predetermined alternation time t aThe process is executed. Specifically, the control unit 64 of the control unit 6 sends a control signal to the low-temperature linear valve 42b to close it, and also sends a control signal to the high-temperature linear valve 42a to open it by a predetermined amount. As a result, the hot water supplied from the high-temperature hot water supply pipe 40a is mixed with the hot water in the bathtub body 2, which is drawn in from the bathtub water intake 9b (Figure 2) and discharged from the discharge port 8a of the water discharge device 8, and the temperature of the hot water discharged from the discharge port 8a rises. As a result, the hot water is applied to the neck and shoulders of the bather, providing a warming sensation to the bather. In this embodiment, the control unit 64 controls the opening of the high-temperature linear valve 42a so that the hot water discharged from the discharge port 8a of the water discharge device 8 is approximately 2°C higher than the reference temperature of the hot water in the bathtub body 2. In the time chart of Figure 11, time t 13 The application of warmth to bathers has begun.

[0102] time t 13 After the application of thermal stimulation is initiated, a predetermined alternation time t a Once this time has elapsed, the process in the flowchart shown in Figure 10 proceeds from step S20 to S23, and time t 13 The warming sensation that was initiated will continue for approximately 2 minutes.

[0103] In step S23, it is determined whether the bather has left the bath (exited the bathtub 2). If the bather has left the bath, the process shown in the flowchart in Figure 10 is completed. If the bather has not left the bath, the process proceeds to step S24.

[0104] In step S24, it is determined whether the application of the cooling and warming stimuli has been repeated a predetermined number of times. If the application of the cooling and warming stimuli has been repeated a predetermined number of times, one process in the flowchart shown in Figure 10 is completed. If it has not been repeated a predetermined number of times, the process returns to step S19, and the application of the cooling stimuli is performed again. (Note that if step S24 is executed after the processes of steps S19 and S20 have been performed, the process in the flowchart returns to step S19. If step S24 is executed after the processes of steps S21 and S22 have been performed, the process in the flowchart returns to step S21.) In this embodiment, the predetermined number of repetitions is set to 3.

[0105] In the example shown in Figure 11, the predetermined shift time t a After the application of thermal stimulation, at time t 14 In this case, the process in the flowchart returns to step S19, and the application of the cooling stimulus is restarted. Thus, in the flowchart of Figure 10, when the process of steps S19→S20→S23→S24→S19 is repeated three times, the process proceeds to step S24→END, and one cycle of the flowchart shown in Figure 10 is completed. Also, if the bather leaves the bath during the repetition of the process of steps S19→S20→S23→S24→S19, one cycle of the flowchart shown in Figure 10 is completed (step S23→END).

[0106] On the other hand, in the flowchart shown in Figure 10, after the processing in step S14 is performed, if it is determined that the second condition for blood flow is satisfied while the processing in steps S15→S16→S17→S18→S15 is repeatedly executed, the processing from step S21 onwards is executed. That is, in step S17, it is determined whether the blood flow acquired by the biological information acquisition unit 56 satisfies a predetermined second condition. In step S17, it is determined that the second condition is satisfied when the decreasing blood flow becomes less than or equal to a predetermined lower threshold. In this embodiment, it is determined that the second condition is satisfied when the blood flow becomes less than 6 (mL / min / 100g). Preferably, this lower threshold for blood flow is set to 5-8 (mL / min / 100g).

[0107] If it is determined that the second condition is satisfied, the process in the flowchart proceeds from step S17 to S21, and in step S21, a predetermined shift time t a A warming stimulus is applied, and in step S22, a predetermined alternation time t a A cooling sensation is applied. In this case, the process of steps S21→S22→S23→S24→S21 is repeated three times, after which the process shown in the flowchart in Figure 10 is completed (step S24→END). Also, if the bather leaves the bath during the repetition of the process of steps S21→S22→S23→S24→S21, the process shown in the flowchart in Figure 10 is completed in one cycle (step S23→END).

[0108] On the other hand, in the flowchart shown in Figure 10, if the bather leaves the bath while the processes of steps S15→S16→S17→S18→S15 are being repeatedly executed after the process of step S14 has been completed, then one cycle of the flowchart shown in Figure 10 is terminated (step S18→END).

[0109] Thus, in the bathtub device of the second embodiment of the present invention, after the discharge of hot water from the water discharge device 8 begins, when the blood flow rate of the bather satisfies the first or second condition, the application of a cooling sensation (in the case of step S16 → S19) or a warming sensation (in the case of step S17 → S21) begins. Thereafter, a predetermined alternation time t a Each time, a cooling sensation and a warming sensation are applied alternately, and the application of cooling and warming sensations is repeated a maximum of three times.

[0110] According to the bathtub device of the second embodiment of the present invention, after first applying a cooling or warming stimulus, a predetermined alternation time t a Since cooling and warming stimuli are applied alternately, it is possible to prevent prolonged continuous application of cooling or warming stimuli, even when heart rate or blood flow cannot be measured.

[0111] Furthermore, according to the bathtub device of this embodiment, when the blood flow rate becomes greater than a predetermined upper threshold (Figure 11, t 12 or t 14 ), or when it becomes smaller than a predetermined lower threshold (Figure 11 t 13 ), and since the warming and cooling sensations can be switched, the stimulation can be changed at the appropriate time, providing the bather with either a warming or cooling sensation that has a fatigue-relieving effect.

[0112] In this embodiment, the stimulation begins with a cooling sensation after bathing begins. However, as a variation, the present invention can also be configured so that, for example, when body temperature is low, such as in winter, and the initial blood flow is low and the blood flow is below a predetermined lower threshold, the stimulation begins with a warming sensation. This allows the stimulation to be started at an appropriate time even when the initial blood flow is low.

[0113] Furthermore, in the second embodiment described above, when the blood flow rate became greater than a predetermined upper threshold, it was determined that the first condition for an increase in blood flow rate was satisfied, and when the blood flow rate became less than a predetermined lower threshold, it was determined that the second condition for a decrease in blood flow rate was satisfied. In contrast, as a modification, the first and second conditions can also be set in the same way as in the first embodiment described above. That is, in step S16 of the flowchart shown in Figure 10, it can be determined that the first condition is satisfied when the blood flow rate increases by a predetermined first difference value from the reference value, and in step S17, it can be determined that the second condition is satisfied when the blood flow rate decreases by a predetermined second difference value from the reference value.

[0114] Furthermore, the first and second conditions in the first embodiment described above can also be set in the same way as in the second embodiment. That is, the present invention can be configured such that in step S6 of the flowchart shown in Figure 8, it is determined that the first condition is satisfied when the blood flow rate becomes greater than a predetermined upper threshold, and in step S7, it is determined that the second condition is satisfied when the blood flow rate becomes less than a predetermined lower threshold.

[0115] The bathtub device according to the embodiments of the present invention has been described above, but various modifications can be made to the embodiments described above. In particular, in the first and second embodiments described above, the first and second conditions were determined based on blood flow rate, but as a modification, the present invention can also be configured so that the first and second conditions are determined based on the bather's heart rate. Since the bather's heart rate changes in much the same way as blood flow rate, similar control can be performed based on the bather's heart rate.

[0116] In other words, the present invention can also be configured such that when the heart rate rises by a predetermined first difference value from a reference heart rate, it is determined that the first condition is satisfied, and when the heart rate falls by a predetermined second difference value from a reference heart rate, it is determined that the second condition is satisfied. For example, the first difference value of the heart rate can be set to 3 bpm and the second difference value to 2 bpm.

[0117] Alternatively, the present invention can be configured such that the first condition is deemed satisfied when the heart rate exceeds a predetermined upper threshold, and the second condition is deemed satisfied when the heart rate falls below a predetermined lower threshold. For example, the upper threshold for heart rate can be set to 87 bpm and the lower threshold to 77 bpm. Preferably, the upper threshold for heart rate is set to 85-90 bpm and the lower threshold to 75-80 bpm.

[0118] Furthermore, the first condition can be defined by the rate of increase in blood flow or heart rate, and the second condition can be defined by the rate of decrease in blood flow or heart rate. That is, the present invention can be configured such that when the rate of increase in heart rate or blood flow exceeds a predetermined rate of increase, it is determined that the first condition is satisfied, and when the rate of decrease in heart rate or blood flow exceeds a predetermined rate of decrease, it is determined that the second condition is satisfied. For example, the present invention can be configured such that when blood flow increases by 2 mL / min / 100g or more per minute, it is determined that the first condition is satisfied, and when blood flow decreases by 2 mL / min / 100g or more per minute, it is determined that the second condition is satisfied. Alternatively, the present invention can be configured such that when heart rate increases by 2 bpm or more per minute, it is determined that the first condition is satisfied, and when heart rate decreases by 2 bpm or more per minute, it is determined that the second condition is satisfied.

[0119] According to this modified version, when the rate of increase or decrease in heart rate or blood flow exceeds a predetermined value, the warming and cooling stimuli are switched. This allows the stimuli to be switched at the appropriate time, providing the bather with a warming or cooling stimuli that promotes fatigue recovery.

[0120] Furthermore, in the first and second embodiments described above, the electrocardiogram signal of the bather was detected by electrodes installed in the bathtub body, and the blood flow rate was estimated based on this. In contrast, as a modification, the present invention can also be configured to estimate the bather's heart rate and blood flow rate based on the temperature of the water stored in the bathtub body and the time the bather is immersed in the water in the bathtub body.

[0121] The upper graph in Figure 12 shows an example of the temporal change in blood flow of a bather immersed in 38°C water, which is hotter than the average bather's body temperature. The lower graph shows an example of the temporal change in blood flow when a bather immersed in 38°C water is given a cooling stimulus at 32°C, which is hotter than the average bather's body temperature. As shown in the upper graph of Figure 12, when a bather is immersed in water hotter than their body temperature before bathing, blood flow increases over time. Also, as shown in the lower graph of Figure 12, when a bather is given a cooling stimulus at a temperature lower than their body temperature before bathing, blood flow decreases over time.

[0122] Thus, there is a certain relationship between the temperature of the water in the bathtub and the temporal change in the blood flow rate of the bather immersed in it. Based on the temperature of the water in the bathtub and the time the bather is immersed in the water, the amount of change in the bather's blood flow rate can be estimated. For this reason, the water temperature acquisition unit 62 built into the control unit 6 acquires the temperature of the water in the bathtub, and the elapsed time detection unit 60 detects the time the bather is immersed in the water, thereby allowing the change in the bather's blood flow rate to be estimated. As a result, the biological information acquisition unit 56 can estimate the bather's blood flow rate based on the elapsed time detected by the elapsed time detection unit 60 and the water temperature acquired by the water temperature acquisition unit 62.

[0123] Furthermore, Figure 12 shows the relationship between the temperature of the bathwater in the bathtub and the temporal change in the blood flow rate of the bather immersed in it. A similar trend in this relationship is known to exist for the temporal change in the bather's heart rate. As a result, the biometric information acquisition unit 56 can estimate the bather's heart rate based on the elapsed time detected by the elapsed time detection unit 60 and the temperature of the bathwater acquired by the bathwater temperature acquisition unit 62. Furthermore, the bather's heart rate may be estimated from the bather's heart rate interval. Note that detecting the bather's heart rate also includes detecting the heart rate interval, which indirectly indicates the bather's heart rate.

[0124] In this way, based on the temperature of the water in the bathtub and the time the bather is immersed in it, it is possible to estimate the change in the bather's blood flow and the change in the bather's heart rate, and based on this, it is possible to determine whether a predetermined first condition and a predetermined second condition are satisfied.

[0125] According to this modified version, the bather's heart rate or blood flow rate is estimated based on the elapsed time since the bather entered the bathtub body 2 and the temperature of the water stored in the bathtub body 2. Therefore, the heart rate or blood flow rate can be easily estimated without the need for special sensors.

[0126] Furthermore, in the above-described embodiment, a water discharge device 8, etc., was provided as a heating and cooling device to provide bathers with warm and cool sensations. As a variation, a heating and cooling device can be installed on the ceiling of the bathroom, etc., and this can be used as a heating and cooling device to send warm air at a temperature higher than a predetermined standard temperature and cool air at a temperature lower than a predetermined standard temperature to the bather in the bathtub body 2. Alternatively, a mist generator can be provided as a heating and cooling device, and the present invention can be configured to provide bathers with warm and cool sensations by generating mist at a temperature higher than a predetermined standard temperature and mist at a temperature lower than a predetermined standard temperature in the bathroom or in the bathtub body 2. Furthermore, a heating / cooling device that can heat and cool the wall surface can be installed on the backrest surface 2a, etc., of the bathtub body 2, and this can be used as a heating and cooling device to provide bathers with warm and cool sensations.

[0127] Furthermore, in the embodiment described above, the temperature of the water stored in the bathtub body 2 was used as the reference temperature, and the bather was given a warming sensation higher than this reference temperature and a cooling sensation lower than this reference temperature. In contrast, as a variation, the average body temperature of the bather during bathing (for example, about 37°C) can also be used as the reference temperature. [Explanation of symbols]

[0128] 1. Bathtub equipment 2 Bathtub body 2a Backrest surface 2b Apron 4a negative electrode 4b Positive electrode 4c reference electrode 6. Control Unit 6a Remote control 8a Spout 9 Circulation device 9a Bathtub spout 9b Bathtub water intake 10 Electrode section 10a Disc section 10b Shaft 12a Front gasket 12b Rear gasket 14 Flange 16 Moisture-proof tube 18 Connection terminals 20 Fixing screws 22 Conductor 24 sheath 40a High temperature hot water supply pipe 40b Low temperature hot water supply pipe 42a High-temperature side linear valve 42b Low-temperature linear valve 44 Mixing chamber 46 Bathtub temperature sensor 48. Water discharge temperature sensor 50a High-temperature side temperature sensor 50b Low-temperature sensor 52 Water heater 54. Water supply 54a Branch 56. Biological Information Acquisition Unit 58 Body temperature acquisition section 60 Elapsed time detection unit 62 Hot water temperature acquisition section 64 Control Unit

Claims

1. A bathtub device that can provide bathers with both warm and cool sensations, A bathtub body equipped with a drain for storing hot water and for discharging the stored hot water, This bathtub unit includes a biometric information acquisition unit that acquires the heart rate or blood flow rate of the bather inside the bathtub, A heating and cooling device that directly applies hot and cold water discharged from the bathtub body to the bather, thereby providing the bather with a thermal sensation higher than a predetermined standard temperature and a cooling sensation lower than a predetermined standard temperature. A body temperature acquisition unit that acquires the body temperature of the bather, The system includes a control unit that controls the heating / cooling device based on the heart rate or blood flow rate acquired by the above-mentioned biological information acquisition unit, The control unit controls the heating and cooling device to provide a cooling sensation to the bather when an increase in heart rate or blood flow, as obtained by the biological information acquisition unit, satisfies a predetermined first condition, and controls the heating and cooling device to provide a warming sensation to the bather when a decrease in heart rate or blood flow, as obtained by the biological information acquisition unit, satisfies a predetermined second condition. The control unit controls the heating and cooling device so that, after a predetermined waiting time has elapsed since the bather entered the bathtub, the application of a cooling or warming stimulus to the bather is initiated based on the heart rate or blood flow rate acquired by the biological information acquisition unit, and the waiting time is changed based on the bather's body temperature acquired by the body temperature acquisition unit.

2. The bathtub device according to claim 1, wherein the above-mentioned biological information acquisition unit is configured to detect or estimate the bather's heart rate, and the above-mentioned control unit estimates the bather's body temperature based on the bather's heart rate.

3. The bathtub apparatus according to claim 1, wherein the control unit first provides a bather with a cooling or warming stimulus, and then controls the heating and cooling device to provide the cooling and warming stimulus alternately at predetermined alternation intervals.

4. A bathtub device that can provide a bather with a warming sensation and a cooling sensation, A bathtub body equipped with a drain for storing hot water and for discharging the stored hot water, This bathtub unit includes a biometric information acquisition unit that acquires the heart rate or blood flow rate of the bather inside the bathtub, A heating and cooling device that directly applies hot and cold water discharged from the bathtub body to the bather, thereby providing the bather with a thermal sensation higher than a predetermined standard temperature and a cooling sensation lower than a predetermined standard temperature. The system includes a control unit that controls the heating / cooling device based on the heart rate or blood flow rate acquired by the above-mentioned biological information acquisition unit, The control unit controls the heating and cooling device to provide a cooling sensation to the bather when an increase in heart rate or blood flow, as obtained by the biological information acquisition unit, satisfies a predetermined first condition, and controls the heating and cooling device to provide a warming sensation to the bather when a decrease in heart rate or blood flow, as obtained by the biological information acquisition unit, satisfies a predetermined second condition. Furthermore, when the control unit first provides a cooling or warming stimulus to the bather, it uses the heart rate or blood flow rate at the time the bather enters the bathtub, or after a predetermined waiting period has elapsed, as a reference. When the heart rate or blood flow rate rises to a predetermined value from the standard heart rate or blood flow rate, it is determined that the first condition is satisfied. When the heart rate or blood flow rate falls to a predetermined value from the standard heart rate or blood flow rate, it is determined that the second condition is satisfied. The control unit, after initially providing a cooling or warming stimulus to the bather, determines that the first condition is satisfied when the heart rate increases to a predetermined value or the blood flow rate increases to a predetermined value from the start of the warming stimulus, and determines that the second condition is satisfied when the heart rate decreases to a predetermined value or the blood flow rate decreases to a predetermined value from the start of the cooling stimulus.

5. The bathtub apparatus according to claim 1, wherein the control unit determines that the first condition is satisfied when the heart rate or blood flow rate becomes greater than a predetermined upper threshold, and determines that the second condition is satisfied when the heart rate or blood flow rate becomes less than a predetermined lower threshold.

6. The bathtub device according to claim 1, wherein the control unit determines that the first condition is satisfied when the rate of increase in heart rate or blood flow exceeds a predetermined rate of increase, and determines that the second condition is satisfied when the rate of decrease in heart rate or blood flow exceeds a predetermined rate of decrease.

7. Furthermore, the bathtub device according to claim 1, further comprising a plurality of electrodes provided on the bathtub body, wherein the biological information acquisition unit estimates the blood flow rate of the bather based on the electrocardiogram signals detected by the plurality of electrodes.

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