JP2019058315A - Submergence determination system, submergence determination method, and program - Google Patents

Abstract

To securely detect whether or not a bather in a bathtub is in a bathing posture that may proceed into a submergence state.SOLUTION: A submergence determination system 1 comprises: an ultrasonic wave transmitter/receiver 2 that is disposed on a ceiling 5 positioned over a bathtub 4 of a bath room and transmits an ultrasonic wave to the bathtub 4 to receive a reflected wave thereof; and a submergence determination device 3 that, on the basis of the received reflected wave, calculates a parietal region distance 7D, a distance from the ultrasonic wave transmitter/receiver 2 to a bather 6's parietal region 7, and an edge part top surface distance 8D, a distance from the ultrasonic wave transmitter/receiver 2 to the bathtub 4's edge part top surface 8, compares the parietal region distance 7D with the edge part top surface distance 8D, and, on the basis of a result of the comparison, determines whether or not the bather 6 is in a bathing posture that may proceed into a submergence state.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a submersion determination system, submersion determination method, and program.

  Patent Document 1 measures the distance between the water surface of the bath and the upper end of the body of the bather using an ultrasonic wave receiver / receiver provided on the ceiling of the bath, and based on the measurement result, the bather's It discloses a technique for determining the state of submersion.

Patent No. 5488995 gazette

  However, the water surface of the bathtub tends to fluctuate up and down, and the reliability of the above determination result is low.

  An object of the present invention is to provide a technique for reliably detecting whether a bather in a bathtub is in a bathing posture which may progress to a submerged state.

The submersion determination system according to one embodiment is disposed at an upper portion of a bathtub, transmits ultrasonic waves toward the bathtub, receives at least one reflected wave, and receives the reflected wave. Based on the distance from the at least one ultrasound emitting and receiving device to the top of the head of the bather and the edge being a distance from the at least one ultrasound emitting and receiving device to the upper surface of the bath edge Part top face distance is calculated, the head top part distance and the edge top face distance are compared, and based on the comparison result, whether or not the bathing posture may cause the bather to go into a submerged state And a submersion determination device for determining
In the submersion determination method according to another embodiment, at least one ultrasonic wave emitting / receiving device is disposed at the upper portion of a bath, ultrasonic waves are emitted from the at least one ultrasonic wave emitting / receiving device toward the bath, and reflected waves thereof And a head-to-head distance which is a distance from the at least one ultrasonic wave receiving and receiving device to the top of the bather based on the received and received waves and the received reflected wave, and the at least one ultrasonic wave emitting Calculate the edge upper surface distance which is the distance from the receiving device to the upper surface of the bathtub edge, compare the head top distance with the edge upper surface distance, and based on the comparison result, the bather And d) determining whether the bathing posture is likely to progress to the submersion state.

  According to the present invention, since the edge upper surface distance which hardly fluctuates is used as the comparison object of the head to head distance, in the bathing posture in which the bather in the bath may progress to the submersion state Whether or not there is can be reliably detected.

It is the schematic of a submersion determination system. First Embodiment It is a bird's-eye view of the bathroom. First Embodiment It is a figure showing a bathing posture. First Embodiment It is a functional block diagram of a submersion judging device. First Embodiment It is explanatory drawing of the ranging using an ultrasonic wave. First Embodiment It is a control flow in the submersion determination system. First Embodiment It is a functional block diagram of a submersion judging device. Second Embodiment It is a bird's-eye view of the bathroom. Second Embodiment It is explanatory drawing of the ranging using an ultrasonic wave. Second Embodiment

First Embodiment
Next, a first embodiment of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic, and the relationship between the thickness and the planar dimension, the ratio of the thickness of each layer, and the like are different from the actual ones. Therefore, specific thicknesses and dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that parts having different dimensional relationships and ratios among the drawings are included.

  In addition, the embodiments described below illustrate apparatuses and methods for embodying the technical idea of the present invention, and the technical idea of the present invention includes materials, shapes, structures, and the like of components. The arrangement etc. are not specified to the following. Various changes can be added to the technical idea of the present invention within the scope of the claims.

(Submersion judgment system)
As shown in FIG. 1, the submersion determination system 1 according to the present embodiment includes an ultrasonic wave emitting and receiving device 2 and a submersion determination device 3. The ultrasonic wave generator / receiver 2 is disposed on the ceiling 5 located above the bath tub 4 of the bathroom, transmits ultrasonic waves toward the bath tub 4 and receives the reflected wave. The ultrasonic wave generator / receiver 2 is disposed at the top of the bathtub 4. The submersion judging device 3 is based on the reflected wave received by the ultrasonic wave emitting and receiving device 2 and has an overhead distance 7D which is a distance from the ultrasonic wave emitting and receiving device 2 to the head 7 of the bather 6 Edge top surface distance 8D, which is the distance from the device 2 to the edge top surface 8 of the bathtub 4, is calculated, the head top distance 7D is compared with the edge top surface distance 8D, and the bather is based on the comparison result. It is judged whether 6 is a bathing posture which may progress to a submersion state.

  An alarm device 9 is connected to the submersion determination device 3. The submersion determination device 3 and the alarm device 9 can be installed at any place inside or outside the bathroom, and may be incorporated in the ultrasonic wave emitting and receiving device 2. The ultrasonic wave generation and reception device 2, the water immersion judgment device 3 and the alarm device 9 may be connected to each other by wire, may transmit and receive signals wirelessly, and may be connected via the Internet.

  FIG. 2 is a bird's-eye view of the household bathroom as viewed from the ceiling 5. As shown in FIG. 2, the ceiling 5 can generally overlook the inside of the bathroom. A washroom 10 and a bathtub 4 are provided in the bathroom. Hot water 11 for bathing is put on the bathtub 4. In the bathroom, drowning in the bath may be unconscious for some reason when bathed in hot water 11 or the brain or heart may become ischemic due to a rapid drop in blood pressure when standing up to get out of bath 4 As a result, the head of the bather 6 sinks in the hot water 11 of the bath 4 and is generated when the hot water 11 of the bath 4 blocks the respiratory organs such as the nose and the mouth. Hereinafter, the “submersion state” means a state in which the head of the bather 6 is submerged in the hot water 11 of the bath 4.

  The bathing posture in bath 4 of bather 6 is shown in Drawing 3 (a) and Drawing 3 (b). FIG. 3A shows a bathing posture in which the top of the head 7 of the bather 6 is positioned sufficiently above the upper surface 8 of the edge. In FIG. 3 (b), for example, the bather 6 can not support itself due to loss of consciousness, and the head 7 of the bather 6 falls and approaches the upper surface 8 of the edge, and is taking a bath It shows the attitude.

  The ultrasonic wave generator / receiver 2 shown in FIG. 1 intermittently transmits ultrasonic waves for a short time toward the entire bath 4. Furthermore, the ultrasonic wave generator / receiver 2 receives a reflected wave (echo wave) in which the transmitted ultrasonic wave is reflected at the top of the head 7 of the bather 6, the upper edge 8 of the edge of the bath 4, or the accessory of the bath 4 or the like. .

  As shown in FIG. 4, the submersion determination apparatus 3 includes a pulse generation circuit 20, an oscillation circuit 21, an intermittent circuit 22, a transmission amplification circuit 23, a transmission / reception switching circuit 24, a reception amplification circuit 25, a filter circuit 26, and waveform analysis. The circuit 27 includes a head top reflection wave extraction unit 28, an edge top reflection wave extraction unit 29, a difference calculation unit 30, and a submersion determination unit 31. The head top reflection wave extraction unit 28, the edge top surface reflection wave extraction unit 29, the difference calculation unit 30, and the submersion determination unit 31 are configured by, for example, a logic circuit of a central processing unit (CPU).

  The oscillation circuit 21 generates an alternating current signal in the ultrasonic band. The pulse generation circuit 20 generates a pulse for determining the transmission and reception time of the ultrasonic wave, and outputs the pulse to the transmission and reception switching circuit 24, the intermittent circuit 22 and the waveform analysis circuit 27. The intermittent circuit 22 is controlled by the pulse from the pulse generation circuit 20, and converts the AC signal from the oscillation circuit 21 into an AC waveform having a pulse-like amplitude. The transmission amplifier circuit 23 amplifies the alternating current signal from the intermittent circuit 22.

  The transmission / reception switching circuit 24 is controlled by the pulse from the pulse generation circuit 20 to switch the transmission / reception of the ultrasonic wave transmission / reception device 2. Pulsed ultrasonic waves with a short duration width are emitted toward the bath 4 by the ultrasonic wave generator / receiver 2. The ultrasonic waves are reflected on the top of the head 7 of the bather 6, the upper surface 8 of the edge, and the peripheral portion of the bath 4 and reach the ultrasonic wave generator / receiver 2 again. At the time when the reflected wave arrives, the transmission / reception switching circuit 24 switches the connection destination of the ultrasonic wave emitting / receiving device 2 to the reception amplification circuit 25.

  The reception amplifier circuit 25 amplifies the reflected wave received by the ultrasonic wave generator / receiver 2. The filter circuit 26 removes frequency components other than the frequency component of the ultrasonic wave transmitted by the ultrasonic wave generator / receiver 2. The output from the filter circuit 26 is input to the waveform analysis circuit 27.

  5 (a) and 5 (b) show the received waveform input to the waveform analysis circuit 27 in each bathing posture shown in FIGS. 3 (a) and 3 (b). (Tx) indicates a transmission waveform as a reference for distance measurement, and (rx) indicates a reception waveform.

  As shown in FIGS. 5 (a) and 5 (b), when an ultrasonic wave is transmitted from the ultrasonic wave generator / receiver 2 to the bathtub 4, first, the bather at the closest position from the ultrasonic wave transmitter / receiver 2 6, the reception waveform W11 reflected at the top of the head 7 is observed, next, the reception waveform W12 reflected at the upper surface 8 of the edge of the bath 4 is observed, and then the reception waveform W13 reflected at the water surface of the hot water 11 is observed Be done.

  Here, since the bather 6 does not have a sudden movement or a periodic movement, the reception waveform W11 corresponding to the bather 6 can be clearly distinguished from other reception waveforms. Further, since the upper edge surface 8 is a fixed object, the received waveform W12 corresponding to the upper edge surface 8 has no change in the reception intensity or the appearance timing, and thus the received waveform W12 corresponding to the upper edge surface 8 receives another It can be clearly distinguished from the waveform. And since the wave by the standing wave determined by the shape of the bathtub 4 exists on the water surface of the hot water 11, the reflected wave corresponding to the water surface of the hot water 11 tends to be periodic and have a relatively short fluctuation period. Therefore, the reception waveform W13 corresponding to the water surface of the hot water 11 can be clearly distinguished from other reception waveforms.

  The waveform analysis circuit 27 shown in FIG. 4 performs envelope detection on the reception waveform input from the filter circuit 26 and outputs an envelope detection waveform.

  The parietal part reflected wave extraction unit 28 receives the received waveform W11 from the received reflected wave based on the received waveform output from the waveform analysis circuit 27 and / or the envelope detection waveform thereof, and the head part 7 of the bather 6 It extracts as a reflected wave in. Also, the edge top surface reflected wave extraction unit 29 generates the reception waveform W12 from the received reflected wave based on either one or both of the reception waveform output from the waveform analysis circuit 27 and its envelope detection waveform. It is extracted as a reflected wave on the part upper surface 8.

  The difference calculating unit 30 is configured to receive the ultrasonic wave from the ultrasonic wave generator / receiver 2 based on the reflected wave (received waveform W11) of the head 7 of the bather 6 extracted by the head reflected wave extraction unit 28. Calculate the head-to-head distance 7D, which is the distance up to 7. In addition, the difference calculating unit 30 is configured to receive the ultrasonic wave from the ultrasonic wave emitting / receiving device 2 based on the reflected wave (received waveform W12) on the edge upper surface 8 of the bathtub 4 extracted by the edge upper surface reflected wave extracting unit 29. An edge top surface distance 8D which is a distance to the edge top surface 8 is calculated. Then, the difference calculating unit 30 compares the parietal distance 7D with the edge upper surface distance 8D. Specifically, the difference calculating unit 30 calculates a difference obtained by subtracting the head top distance 7D from the edge upper surface distance 8D.

  In the difference calculation unit 30, the delay time from the transmission of an ultrasonic wave to the reception of the reflected wave at the head top 7 of the bather 6 extracted by the head reflected wave extraction unit 28 is calculated. It can be calculated by multiplying the calculated delay time by the propagation speed of the ultrasonic wave.

  Similarly, in the difference calculation unit 30, the edge upper surface distance 8D is a delay from the transmission of an ultrasonic wave to the reception of the reflected wave on the edge upper surface 8 of the bathtub 4 extracted by the edge upper surface reflected wave extraction unit 29. The time can be calculated by multiplying the calculated delay time by the propagation speed of the ultrasonic wave.

  Further, the propagation velocity v (meters per second) of the sound wave in the dry air at the standard pressure can be obtained by “v = 331.5 + 0.61 T” when the temperature is T degrees Celsius. Therefore, for the head-to-head distance 7D, when the delay time t11 of FIG. 5 is used, “7D = 0.5 × t11 × v = 0.5 × t11 (331.5 + 0.61T)”, and the edge top surface distance 8D Becomes “8D = 0.5 × t12 × v = 0.5 × t12 (331.5 + 0.61 T)” when the delay time t12 in FIG. 5 is used. The difference ΔD obtained by subtracting the head-to-head distance 7D from the edge upper surface distance 8D is “ΔD = 8 D−7 D = 0.5 (t12−t11) (331.5 + 0.61 T)”.

  The submersion determination unit 31 determines whether or not the bathing posture has a possibility that the bather 6 may progress to a submersion state based on the comparison result between the head top distance 7D and the edge upper surface distance 8D by the difference calculation unit 30. judge. Specifically, when the difference ΔD calculated by the difference calculation unit 30 becomes equal to or less than the predetermined value, the submersion determination unit 31 determines that the bathing person 6 has a bathing posture that may possibly progress to the submersion state. . Here, the predetermined value is appropriately set, for example, in the range of 15 cm to 30 cm, and is preferably determined according to the size of the head of the bather 6, the position of the respirator, and the like. The predetermined value is set to, for example, 25 cm. The predetermined value is stored in advance in a storage device (not shown) of the submersion determination device 3 or the like.

  The alarm device 9 issues a warning when it is determined by the submersion determination unit 31 that the bathing person 6 is in a bathing posture that may possibly progress to a submersion state.

(Sinking judgment method)
Next, with reference to FIG. 6, the submersion determination method using the submersion determination system 1 according to the embodiment of the present invention will be described.

Step S100:
First, the ultrasonic wave generator / receiver 2 transmits ultrasonic waves toward the bathtub 1. The transmitted ultrasonic wave is reflected by the bather 6, the upper surface 8 of the edge, the water surface of the hot water 11, etc., and the reflected wave is received by the ultrasonic wave generator / receiver 2.

Step S110:
Next, the waveform analysis circuit 27 outputs the waveform of the reflected wave received by the ultrasonic wave generator / receiver 2 and its envelope detection waveform.

Step S120:
Next, on the basis of the reception waveform output from the waveform analysis circuit 27 and its envelope detection waveform, the parietal part reflected wave extraction unit 28 receives the reception waveform W11 among the received reflection waves at the head part 7 of the bather 6 Extracted as a reflected wave of

Step S130:
Next, based on the received waveform output from the waveform analysis circuit 27 and its envelope detection waveform, the edge upper surface reflected wave extraction unit 29 selects the received waveform W12 among the received reflected waves as the upper surface 8 of the edge of the bathtub 4 It extracts as a reflected wave in.

Step S140:
Next, the difference calculating unit 30 calculates the head-to-head distance 7D based on the reflected wave at the head-top 7 of the bather 6 extracted by the head-top reflected-wave extracting unit 28. Similarly, the difference calculating unit 30 calculates the edge upper surface distance 8D based on the reflected wave on the edge upper surface 8 of the bathtub 4 extracted by the edge upper surface reflected wave extracting unit 29. Then, the difference calculating unit 30 subtracts the head-to-head distance 7D from the edge upper surface distance 8D to calculate the difference ΔD.

Step S150:
Next, the submersion determination unit 31 determines whether the difference ΔD is equal to or less than a predetermined value. If the submersion determination unit 31 determines that the difference ΔD is not equal to or less than the predetermined value, the process ends. On the other hand, when the submersion determination unit 31 determines that the difference ΔD is equal to or less than the predetermined value, the alarm device 9 issues an alarm in step S160, and the process ends.

  The series of procedures shown in FIG. 6 can be executed by controlling the submersion determination system 1 shown in FIG. 1 by a program of an algorithm equivalent to that in FIG. This program may be stored in a storage device or the like (not shown). Further, this program can be stored in a computer readable recording medium, and the recording medium can be read by a storage device to execute the series of procedures of the embodiment of the present invention.

  The first embodiment of the present invention has been described above, but the first embodiment has the following features.

  That is, the submersion determination system 1 is disposed on the ceiling 5 located above the bath tub 4 of the bathroom, transmits ultrasonic waves toward the bath tub 4 and receives the reflected waves, Based on the reflected wave, the distance from the ultrasonic wave generating / receiving device 2 to the upper surface 8 of the edge of the bath 4 is the distance from the ultrasonic wave generating / receiving device 2 to the top of the head 7 of the bather 6 Calculate a certain edge upper surface distance 8D, compare the parietal distance 7D and the edge upper surface distance 8D, and based on the comparison result, in a bathing posture in which the bather 6 may progress to a submerged state And a submersion determination device 3 for determining whether or not there is any. According to the above configuration, since the edge upper surface distance 8D which hardly fluctuates is used as the comparison object of the head top distance 7D, there is a possibility that the bather 6 in the bath 4 may progress to the submerged state Whether it is a bathing posture can be detected reliably.

  In addition, the submersion determination apparatus 3 has a bathing posture in which there is a possibility that the bather 6 may progress to submersion when the difference ΔD obtained by subtracting the head-to-top distance 7D from the edge upper surface distance 8D becomes equal to or less than a predetermined value. judge. According to the above configuration, it is possible to detect by a simple calculation that the bather 6 is in a bathing posture which may progress to a submerged state.

  In addition, the method of determining water immersion arranges the ultrasonic wave emitting and receiving device 2 on the ceiling 5 located above the bathtub 4 of the bathroom, and transmits ultrasonic waves from the ultrasonic wave emitting and receiving device 2 toward the bathtub 4 and the reflected wave Head distance distance 7D which is the distance from the ultrasonic wave generator / receiver 2 to the top of the head 7 of the bather 6 based on the received / received step (S100) and the received reflected wave, and the ultrasonic wave receiver / receiver Edge top surface distance 8D, which is the distance from 2 to the edge top surface 8 of the bathtub 4, is calculated, and the head top distance 7D is compared with the edge top surface distance 8D (S140), based on the comparison result (S150) It is determined whether it is a bathing posture with which a bather may progress to a submersion state (S150) Submersion determination step (S110-S150). According to the above method, since the edge upper surface distance 8D which hardly fluctuates is used as a comparison object of the head top distance 7D, there is a possibility that the bather 6 in the bath 4 may progress to a submerged state Whether it is a bathing posture can be detected reliably.

  In addition, an ultrasonic sensor for water may be provided in the bathtub 4, and the presence or absence of a bather may be determined prior to the water immersion determination by the ultrasonic sensor.

Second Embodiment
Next, a second embodiment will be described with reference to FIGS. 7 to 9.

  In the first embodiment, as shown in FIG. 4, the submersion determination system 1 is provided with only one ultrasonic wave emitting and receiving device 2. On the other hand, in the submersion determination system 1 according to the present embodiment, as shown in FIG. 7, the long side ultrasonic wave emitting and receiving apparatus 40 and the short side ultrasonic wave emitting and receiving apparatus 41 as ultrasonic wave emitting and receiving apparatuses Is equipped. The submersion determination apparatus 3 further includes a directivity switching circuit 32 and a directivity switching control circuit 33.

  As shown in FIG. 8, the bathtub 4 has a long side direction coinciding with the longitudinal direction of the drawing and a short side direction coincident with the lateral direction of the drawing in plan view. The bathtub 4 has, in a plan view, a longitudinal direction coinciding with the paper longitudinal direction, and a lateral direction coinciding with the paper lateral direction.

  The long side ultrasonic wave generator / receiver 40 is configured to be able to transmit ultrasonic waves having a narrow directivity in the long side direction and the short side direction in the long side direction of the bathtub 4 as shown by the oval broken line 40a in FIG. It is done. According to the wide directivity in the direction of the long side of the bath 4, ultrasonic waves are emitted toward the top of the head 7 of the bather 6 with no problem, regardless of which side the bather 6 is facing. Preferably, the ultrasonic waves transmitted by the long side ultrasonic wave generator / receiver 40 may be transmitted only to the region inside the upper edge surface 8 of the bath 4.

  The short side ultrasonic wave emitting and receiving apparatus 41 is configured to be able to transmit an ultrasonic wave having a wide directivity in the narrow side direction and the narrow side direction of the bathtub 4 as indicated by the oval broken line 41a in FIG. It is done. Preferably, the ultrasonic wave transmitted by the short side ultrasonic wave generator / receiver 41 is transmitted to a region including the upper edge surface 8 on the long side of the bathtub 4 and not including the upper edge surface 8 on the short side of the bathtub 4 Good to be done. In addition, preferably, the center of the region of the ultrasonic wave transmitted by the short side ultrasonic wave generator 41 substantially coincides with the center in the long side direction and the center in the short side direction of the bathtub 4 in plan view. According to the above directivity, ultrasonic waves are not transmitted toward the top of the head 7 of the bather 6.

  In order to impart directivity to the ultrasonic waves emitted by the long side ultrasonic wave emitting and receiving apparatus 40 and the short side ultrasonic wave emitting and receiving apparatus 41, various known means already known can be applied. For example, firstly, the ultrasonic radiation surface should be slightly uneven. That is, the convex portion of the ultrasonic radiation surface has an action of broadening the directivity, and the concave portion has an action of narrowing the directivity. Second, if the thickness of the case for housing the piezoelectric element is uneven, the vibration can be suppressed in the thick portion, and non-uniform directivity can be obtained.

  Returning to FIG. 7, the directivity switching control circuit 33 outputs control signals to the directivity switching circuit 32 at predetermined time intervals.

  The directivity switching circuit 32 receives the connection destination of the transmission / reception switching circuit 24 every time a control signal is input from the directivity switching control circuit 33, and the long side ultrasonic emission / reception device 40 and the short side ultrasonic emission / reception It switches between the devices 41. With the above configuration, the long side ultrasonic wave generator / receiver 40 and the short side ultrasonic wave transmitter / receiver 41 are configured to emit and receive ultrasonic waves at different timings. For example, generation and reception of ultrasonic waves by the long side ultrasonic wave generator and receiver 40 and generation and reception of ultrasonic waves by the short side ultrasonic wave generator and receiver 41 are alternately performed.

  According to the above configuration, the ultrasonic wave transmitted from the long side ultrasonic wave generator / receiver 40 is likely to be reflected at the top of the head 7 of the bather 6 and is not likely to be reflected at the upper edge 8 of the bath 4. Therefore, as shown in FIG. 9A, the reception waveform W11 corresponding to the top of the head 7 of the bather 6 appears in the reception waveform at the long side ultrasonic wave generator / receiver 40, but The corresponding received waveform W12 hardly appears. Therefore, the reception waveform W11 corresponding to the top of the head 7 of the bather 6 can be distinguished from the reception waveform W12 corresponding to the upper surface 8 by analyzing the reception waveform in the long side ultrasonic wave generator / receiver 40. Can be extracted.

  Similarly, the ultrasonic wave transmitted from the short side ultrasonic wave generator / receiver 41 is not likely to be reflected at the top of the head 7 of the bather 6, and is likely to be reflected at the upper edge 8 of the bath 4. Therefore, as shown in FIG. 9B, although the reception waveform W11 corresponding to the top of the head 7 of the bather 6 hardly appears in the reception waveform at the short side ultrasonic wave generator / receiver 41, the upper surface of the edge is The reception waveform W12 corresponding to 8 appears. Therefore, the reception waveform W12 corresponding to the upper surface 8 of the edge is distinguished from the reception waveform W11 corresponding to the parietal region 7 of the bather 6 by analyzing the reception waveform in the short side ultrasonic wave generator / receiver 41 Can be extracted.

  Then, the submersion determination apparatus 3 calculates the parietal distance 7D based on the reflected wave corresponding to the long side ultrasonic wave emitting and receiving apparatus 40, and based on the reflected wave corresponding to the short side ultrasonic wave emitting and receiving apparatus 41. The edge top surface distance 8D is calculated. According to the above configuration, the head top distance 7D and the edge top surface distance 8D can be reliably calculated.

  Thus, it is a matter of course that the present invention includes various embodiments and the like which are not described herein. Accordingly, the technical scope of the present invention is defined only by the invention extraction matters according to the scope of claims appropriate from the above description.

DESCRIPTION OF SYMBOLS 1 submersion determination system 2 ultrasonic wave transmission / reception device 3 submersion determination device 4 bathtub 5 ceiling 6 bather 7 top of head 7 D top of head distance 8 top edge of top 8 D edge top distance 9 alarm device 10 washing place 11 hot water 20 pulse generation circuit 21 oscillation Circuit 22 Intermittent circuit 23 Transmission amplifier circuit 24 Transmission / reception switching circuit 25 Reception amplifier circuit 26 Filter circuit 27 Waveform analysis circuit 28 Head top reflection wave extraction part 29 Edge top reflection wave extraction part 30 Difference calculation part 31 Submersion judgment part 32 Directivity switching circuit 33 Directivity switching control circuit 40 Long-side ultrasonic wave generator / receiver 41 Short-side ultrasonic wave transmitter / receiver W11 Received waveform W12 Received waveform W13 Received waveform

Claims (5)

At least one ultrasound emitting and receiving device disposed at the top of the bathtub, emitting ultrasound toward the bathtub and receiving the reflected waves;
A head-to-head distance which is a distance from the at least one ultrasonic wave emitting and receiving device to the head of the bather based on the received reflected wave, and an upper surface of the bathtub from the at least one ultrasonic wave emitting and receiving device The upper surface distance, which is the distance to the upper end, is calculated, and the distance between the top of the head and the upper surface distance of the edge is compared, and based on the comparison result, the bather may progress to a submerged state A submersion determination device that determines whether or not it is a bathing posture;
Equipped with
Submersion judgment system. The submersion determination system according to claim 1, wherein
The submersion determination apparatus determines that the bather has a bathing posture that may possibly progress to submersion when the difference obtained by subtracting the head-to-head distance from the edge upper surface distance becomes a predetermined value or less.
Submersion judgment system. The submersion determination system according to claim 1 or 2, wherein
The bathtub has a long side direction and a short side direction in plan view,
The at least one ultrasonic wave emitting and receiving apparatus includes a long side ultrasonic wave emitting and receiving apparatus that transmits an ultrasonic wave having a wide directivity in the long side direction of the bath; and a wide directivity in the short side direction of the bath A short side ultrasonic wave emitting and receiving apparatus for transmitting an ultrasonic wave having
The long side ultrasonic wave emitting and receiving apparatus and the short side ultrasonic wave emitting and receiving apparatus are configured to emit and receive the ultrasonic waves at different timings,
The submersion determination device calculates the head-to-head distance based on the reflected wave corresponding to the long side ultrasonic wave emitting and receiving device, and based on the reflected wave corresponding to the short side ultrasonic wave emitting and receiving device Calculating the edge top surface distance,
Submersion judgment system. Placing at least one ultrasonic generator / receiver at the top of the bath, emitting ultrasonic waves from the at least one ultrasonic generator / receiver towards the bath, and receiving its reflected wave;
A head-to-head distance which is a distance from the at least one ultrasonic wave emitting and receiving device to the head of the bather based on the received reflected wave, and an upper surface of the bathtub from the at least one ultrasonic wave emitting and receiving device The upper surface distance, which is the distance to the upper end, is calculated, and the distance between the top of the head and the upper surface distance of the edge is compared, and based on the comparison result, the bather may progress to a submerged state Submersion determination step of determining whether or not the posture is a bathing posture;
including,
Submersion judgment method. On the computer
The submersion determination method according to claim 4 is executed.
program.

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