Detection device

Abstract

To provide a detection device with an improved configuration. [Solution] The detection device comprises a sensor that outputs a signal corresponding to the gas contained in a first gas supplied during a first period, a storage unit that stores the first gas supplied to the sensor, a pump that supplies the first gas stored in the storage unit to the sensor, and a control unit that controls the pump. The first period includes a plurality of operating periods during which the control unit operates the pump, and at least one stopping period during which the control unit stops the pump, the stopping period being provided between the plurality of operating periods.

Description

Technical Field

[0001] This disclosure relates to a detection device for detecting a specific gas.

Background Art

[0002] Conventionally, in a measuring device for measuring a specific gas contained in a gas, a technique for controlling the flow rate of the gas flowing in the device is known (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] There is still room for improvement in the configuration of a detection device for detecting a gas contained in a gas.

[0005] One aspect of this disclosure provides a detection device having a more improved configuration.

Means for Solving the Problems

[0006] In order to solve the above problems, a detection device according to one aspect of this disclosure includes a sensor that outputs a signal corresponding to a gas contained in a first gas supplied in a first period, a storage unit that stores the first gas to be supplied to the sensor, a pump that supplies the first gas stored in the storage unit to the sensor, and a control unit that controls the pump. The first period includes a plurality of operation periods in which the control unit operates the pump and at least one stop period in which the control unit stops the pump. The stop period is provided between the plurality of operation periods.

[0007] Each aspect of the present disclosure may be implemented by a computer, in which case a control program for the detection device that enables the computer to implement the detection device by operating the computer as each part (software element) of the detection device, and a computer-readable recording medium on which the program is recorded, also fall within the scope of the present disclosure. [Effects of the Invention]

[0008] According to one aspect of this disclosure, a detection device having a more improved configuration can be provided. [Brief explanation of the drawing]

[0009] [Figure 1] This is a schematic diagram showing an example of the configuration of a detection device 1 according to one embodiment of the present disclosure. [Figure 2] This is a block diagram showing the main components of the detection device. [Figure 3] This is a conceptual diagram showing the relationship between the elapsed time during the detection period and the operating state of the second pump. [Figure 4] This graph shows the relationship between time during the first period and the flow rate of gas flowing through the second pump. [Figure 5] This graph shows the relationship between the switching frequency between the operating period and the stopping period, and the oscillation frequency of the oscillation circuit. [Figure 6] This graph shows examples of signal waveforms based on signals acquired from three different types of sensors. [Figure 7] This graph shows examples of signal waveforms based on signals obtained using two different types of sensors under the same conditions as the example shown in Figure 6, but with different sensor types than those used to obtain the signal waveform shown in Figure 6. [Figure 8] This graph shows an example of signal waveforms based on signals acquired from the same three types of sensors as shown in the example in Figure 6, during the detection period which includes the first and third periods. [Figure 9] This graph shows an example of a signal waveform based on signals acquired from the same two types of sensors as in the example shown in Figure 7, under the same conditions as the example shown in Figure 8. [Figure 10]This is a schematic diagram showing an example of the configuration of a detection device according to another embodiment of this disclosure. [Figure 11] This graph shows the relationship between the output voltage of the sensor and the elapsed time of the detection period in the detection device according to this embodiment. [Figure 12] This is a schematic diagram showing an example of the configuration of a detection device according to yet another embodiment of the present disclosure. [Modes for carrying out the invention]

[0010] [Embodiment 1] Hereinafter, one embodiment of the present disclosure will be described in detail. Figure 1 is a schematic diagram showing an example of the configuration of a detection device 1 according to one embodiment of the present disclosure. Figure 2 is a block diagram showing the main components of the detection device 1. The detection device 1 collects gas (hereinafter referred to as the first gas) in a predetermined space and detects the type and concentration of a specific gas contained in the first gas. In this embodiment, the detection device 1 is described as being installed in the toilet bowl of a toilet located in a toilet room. The toilet may be a flush toilet, although this is not limited to the toilet. For example, part or all of the detection device 1 may be incorporated inside the toilet bowl or toilet seat. The detection device 1 may collect the gas in the toilet bowl as the first gas, which is the predetermined space.

[0011] The specified gas is a gas originating from the subject and may be included in the first gas. In this disclosure, the specified gas may be, for example, a predetermined component contained in the gas produced from the subject's stool. The specified gas may be at least one of methyl mercaptan (CH3SH), hydrogen sulfide (H2S), hydrogen (H2), and carbon dioxide (CO2). The specified gas may further include, for example, 2-propanol, dimethyl sulfide, trimethylamine, ammonia, methane, butyric acid, acetic acid, or propionic acid.

[0012] The detection device 1 collects, as the first gas, a gas containing a gas generated from the feces of a subject in a toilet bowl which is a predetermined space, and detects the type and concentration of a specific gas contained in the first gas. The unit of concentration may be, for example, ppm. The detection result of the specific gas can be used, for example, for presentation to the subject or for estimating the state of the subject's intestinal environment or the like using the detection result. In the present disclosure, the detection device 1 that collects the gas in the toilet bowl as the first gas will be described as an example. However, the detection device 1 is not limited to this configuration. For example, the detection device 1 may be configured to collect the gas in the toilet room where the toilet is installed as the first gas.

[0013] The use of the detection device 1 is not limited to the above-described use. For example, the detection device 1 may be installed inside a refrigerator as a predetermined space. In this case, the detection device 1 can acquire a gas containing a specific gas generated from food as the first gas. For example, the detection device 1 may be installed in a factory or a laboratory as a predetermined space. In this case, the detection device 1 can acquire a gas containing a specific gas generated from chemicals or the like as the first gas.

[0014] The detection device 1 includes a plurality of openings 40, a storage portion 20, a sensor chamber 30, a sensor 31, a first pump 51, a second pump 52, and a plurality of valves 60. The plurality of openings 40 are openings for taking in external gas into the detection device 1 or for discharging the gas inside the detection device 1 to the outside. As shown in FIG. 1, the detection device 1 may include a first opening 41, a second opening 42, and a third opening 43 as the plurality of openings 40. Further, the detection device 1 includes a plurality of flow paths 70. The first opening 41, the second opening 42, the third opening 43, the storage portion 20, the sensor chamber 30, the first pump 51, the second pump 52, and the plurality of valves 60 may be connected by the plurality of flow paths 70.

[0015] Furthermore, the detection device 1 may include a housing 90 in which the storage portion 20 and the sensor 31 are located inside. When the detection device 1 includes the housing 90, each part other than the storage portion 20 and the sensor 31 may also be located inside the housing 9°.

[0016] The first opening 41 is an opening for taking in the first gas supplied to the sensor 31. The first opening 41 can be exposed to the inside of the toilet bowl. As an example, the first opening 41 may be located between the toilet bowl and the toilet seat. Also, a part of the first opening 41 may be embedded in the toilet seat. The first opening 41 may open toward the inside of the toilet bowl. The first opening 41 takes in, as the first gas, a gas containing a specific gas generated from feces discharged into the toilet bowl by the operation of the first pump 51 connected to the first opening 41.

[0017] The second opening 42 is an opening for taking in the second gas different from the first gas into the detection device 1. The second gas can be used to purge the gas in each part of the detection device 1, for example, the sensor 31, the storage part 20, and each flow path 70. The second opening 42 can be exposed to the outside of the toilet bowl. A part of the second opening 42 may be embedded in the toilet seat. The second opening 42 may open toward the outside of the toilet. The second opening 42 takes in, as the second gas, for example, the air (environmental gas) in the toilet room outside the toilet bowl by the operation of the pump connected to the second opening 42.

[0018] The third opening 43 is an opening for discharging the gas located near the sensor 31, for example, the gas in the sensor chamber 30. The third opening 43 can be exposed to the outside of the toilet bowl. The third opening 43 discharges the exhaust gas from the sensor 31 to the outside through the flow path 70 by the operation of the pump connected to the third opening 43. This exhaust gas may contain the first gas and the second gas after the detection process. Also, the third opening 43 can discharge the residual gas in the storage part 20 to the outside of the detection device 1 through the flow path 70 by the operation of the second pump 52 connected to the third opening 43.

[0019] The first pump 51 is located on the flow path 71 and is connected to the storage part 20 through the flow path 71. The first pump 51 operates based on the control of the main control part 811. The first pump 51 sucks the first gas in the toilet bowl through the first opening 41 that opens toward the inside of the toilet bowl and supplies it to the storage part 20.

[0020] The storage section 20 is capable of storing the first gas. The storage section 20 is a gas bag capable of storing the first gas. The storage section 20 may be made of a flexible material. As shown in Figure 1, the storage section 20 is connected to the sensor chamber 30 via a first flow path 71, a valve 60, and a second flow path 72.

[0021] The flow path 71 is a tubular member for connecting the toilet bowl and the sensor 31. One end of the flow path 71 is connected to a first opening 41 that opens inside the toilet bowl, and the other end is connected to a sensor chamber 30 that houses the sensor 31. The flow path 72 is a flow path located between the first pump 51 and the storage unit 20. The flow path 72 is a flow path that branches off from the flow path 71 and then rejoins the flow path 71. The storage unit 20 may also be located on the second flow path 72. The third flow path 73 may connect the second opening 42 and the first flow path 71. As shown in Figure 1, the third flow path 73 may be connected to the first flow path 71 by a connector 101. The fourth flow path 74 may connect the sensor chamber 30 and the third opening 43. Each opening and each flow path may be made of a tubular member such as a resin tube or a metal or glass pipe.

[0022] The multiple valves 60 are located on the flow path 71 and operate according to the control of the main control unit 811. The multiple valves 60 may be composed of valves that are electromagnetically driven, piezoelectrically driven, or motor-driven. The multiple valves 60 can adjust the degree of opening (degree of communication) of each flow path according to the control of the main control unit 811, thereby adjusting the communication state in the flow path 71 and the communication state between the flow path 71 and the flow path 72.

[0023] When the state of valve 60 is adjusted and the first pump 51 is activated, the first gas is drawn in from the first opening 41 and supplied to the storage unit 20 via the flow path 71. Also, when the state of valve 60 is adjusted and the second pump 52 is activated, the first gas can be supplied from the storage unit 20 to the sensor 31 via the flow paths 72 and 71. Furthermore, when the state of valve 60 is adjusted and the second pump 52 is activated, the second gas is drawn in from the second opening 42 and supplied to the sensor 31 via the third flow path 73 and the first flow path 71. Furthermore, when the second pump 52 is activated, the gas in the sensor chamber 30 is discharged from the third opening 43 via the fourth flow path 74.

[0024] The sensor chamber 30 is a chamber that houses the sensor 31. As shown in Figure 1, one end of the flow path 71 is connected to the sensor chamber 30. The sensor chamber 30 is connected to the storage section 20 via the flow paths 71 and 72. In addition, one end of the fourth flow path 74 is connected to the sensor chamber 30.

[0025] Sensor 31 is a sensor that outputs a signal corresponding to the gas contained in the first gas supplied during the first period. The signal output by sensor 31 may be a signal corresponding to the type or concentration of gas. For example, sensor 31 is a sensor that outputs a signal corresponding to the concentration of sulfur-based gases. For example, sensor 31 may be an electrochemical sensor that reacts to sulfur-based gases. For example, sensor 31 is a sensor that outputs a signal corresponding to the concentration of hydrogen gas. Alternatively, sensor 31 may be a semiconductor sensor that reacts to hydrogen gas.

[0026] Sensor 31 may be supplied with a first gas taken in through the first opening 41. Sensor 31 may be supplied with a first gas taken in through the first opening 41 and stored in the storage unit 20. When the first gas is supplied from the storage unit 20, sensor 31 outputs a signal corresponding to the concentration or type of a specific gas contained in the first gas. Sensor 31 may be housed inside the sensor chamber 30.

[0027] The detection device 1 may be equipped with multiple sensors 31. Each of the multiple sensors 31 may be capable of outputting a signal corresponding to the respective concentration of multiple different types of specific gases. This allows the detection device 1 to detect multiple types of specific gases. Each of the multiple sensors 31 may be capable of outputting a signal corresponding to the concentration of the same type of specific gas. Each of the multiple sensors 31 may have different sensitivities to the same type of specific gas.

[0028] The second pump 52 is a pump that supplies the first gas to the sensor 31. The second pump 52 operates based on the control of the main control unit 811. The second pump 52 is a pump that supplies the first gas stored in the storage unit 20 to the sensor 31. For example, the second pump 52 may be an AC (Alternating Current) pump or a DC (Direct Current) pump. Here, an AC pump is a pump driven by an AC motor, and a DC pump is a pump driven by a DC motor. In this embodiment, the configuration in which the second pump 52 is an AC pump will be described as an example.

[0029] If the second pump 52 is an AC pump, the detection device 1 includes an oscillation circuit 522 that outputs a signal to operate the second pump 52 at a predetermined oscillation frequency. Furthermore, if the second pump 52 is an AC pump, the detection device 1 also includes a power supply 521 that applies a control voltage to the oscillation circuit 522.

[0030] The power supply 521 switches on and off according to the control of the main control unit 811. When the power supply 521 is on, it applies a control voltage to the oscillation circuit 522. The oscillation circuit 522 is a circuit that can output a signal to the second pump 52 to operate the second pump 52 at a predetermined oscillation frequency. The oscillation circuit 522 outputs this signal while the control voltage from the power supply 521 is applied. The second pump 52 operates when it receives a signal from the oscillation circuit 522. For example, the oscillation circuit 522 may be capable of outputting a signal at an oscillation frequency of 50 Hz. In this case, the power supply 521 is turned on by the control of the main control unit 811, and the second pump 52 operates at 50 Hz while the oscillation circuit 522 is outputting a signal. Details of the operation of the second pump 52 will be described later.

[0031] As shown in Figure 2, the detection device 1 includes a control unit 81 and a storage unit 82 in addition to the configuration shown in Figure 1. Furthermore, the detection device 1 may also include a circuit board 80. The control unit 81 and the storage unit 82 may be located on the circuit board 80. The circuit board 80 is a board that includes a control unit 81 that controls the operation of the first pump 51, the second pump 52, and the plurality of valves 60, and a storage unit 82 that stores information used in the detection device 1. The circuit board 80 may further include a communication module for the detection device 1 to communicate with an external device. Also, a power supply 521 and an oscillator circuit 522 for operating the second pump 52 may be located on the circuit board 80.

[0032] The memory unit 82 stores an estimation model M used to estimate the type and concentration of a specific gas based on the signal waveform obtained from the sensor 31. The estimation model M is a trained estimation model that has been trained using a dataset containing multiple pairs of data showing signal waveforms as input data for learning and information showing the type and concentration of a specific gas as training data.

[0033] The input data for learning may be data showing the signal waveform obtained when gas is supplied to the sensor 31 under the same conditions as when the detection device 1 supplies the first gas to the sensor 31. More specifically, the input data for learning may be data showing the signal waveform obtained when gas is supplied to the sensor 31 with the same duty cycle as the operation duty cycle of the second pump 52 when the first gas is supplied in the first period (described later). In addition, information indicating the type and concentration of a specific gas contained in the gas supplied to the sensor 31 when acquiring the input data for learning may be used as training data.

[0034] The type of specific gas used as training data may be one or more. Furthermore, if the detection device 1 is equipped with multiple sensors 31, data showing multiple signal waveforms obtained from each of the multiple sensors 31 may be used as input data for learning. For example, the estimation model M may be an estimation model that takes data showing multiple signal waveforms obtained from each of the multiple sensors 31 as input data and outputs information indicating the types and concentrations of multiple specific gases as output data.

[0035] The control unit 81 performs a series of detection-related controls. The series of detections includes a storage period, which is the period during which a first gas containing a specific gas originating from the subject is stored in the storage unit 20, and a detection period, which is the period during which the stored first gas is supplied to the sensor 31 and the specific gas is detected.

[0036] As shown in Figure 2, the control unit 81 comprises a main control unit 811, an acquisition unit 812, and an estimation unit 813. The control performed by each part of the control unit 81 will be described below. The main control unit 811 controls the state of the valve 60 and the operation of the first pump 51 and the second pump 52 during the storage period and the detection period.

[0037] The detection device 1 may include a person detection unit (not shown). The person detection unit may include at least one of the following: an image camera, a personal identification switch, an infrared sensor, a pressure sensor, and a load sensor. The person detection unit outputs the detection result to the control unit 81. The person detection unit may detect that the person has sat on the toilet seat or that the person has defecated. The person detection unit may output a signal to the control unit 81 indicating that the person has sat on the toilet seat or that the person has defecated. When the main control unit 811 receives a signal from the person detection unit indicating that the person has sat on the toilet seat or that the person has defecated, it starts detecting the specific gas.

[0038] First, the main control unit 811 starts the storage period. During the storage period, the main control unit 811 controls the storage of the first gas in the storage unit 20. Specifically, the main control unit 811 adjusts the state of the valve 60 and operates the first pump 51. The operation of the first pump 51 draws in the first gas from the first opening 41. The first gas drawn in from the first opening 41 is supplied to the storage unit 20 through the first flow path 71 and the second flow path 72. As a result, the first gas is stored in the storage unit 20. The storage period should be set to the time necessary for the storage unit 20 to store more than the amount of first gas used in a series of detections. For example, the storage period may be about 10 to 30 seconds. For example, the storage period may be about 20 to 30 seconds.

[0039] When the storage period ends and the first gas is stored in the storage unit 20, the main control unit 811 starts the detection period. During the detection period, the main control unit 811 performs control to detect a specific gas contained in the first gas. Specifically, the main control unit 811 controls the state of the valve 60 and operates the second pump 52. As a result, the main control unit 811 supplies the first gas stored in the storage unit 20 to the sensor 31. When the first gas is supplied to the sensor 31, the acquisition unit 812 acquires the signal waveform and the estimation unit 813 detects the specific gas.

[0040] Figure 3 is a conceptual diagram showing the relationship between the elapsed time during the detection period and the operating state of the second pump 52. As shown in Figure 3, the detection period includes at least one first period (reference numeral 301). The first period includes a plurality of operating periods (reference numeral 302) during which the main control unit 811 operates the second pump 52, and at least one stop period (reference numeral 303) during which the main control unit 811 stops the second pump 52. The stop period is provided between the plurality of operating periods. As shown in Figure 3, there may be a stop period at the end of the first period that is not provided between the plurality of operating periods. The statement that the stop period is provided between the plurality of operating periods in the first period can also be rephrased as the first period including a plurality of pairs of operating periods and stop periods. During the first period, the main control unit 811 controls the second pump 52 to alternately switch between an operating state and a stopped state.

[0041] The main control unit 811 operates the second pump 52 at a predetermined duty cycle during the first period. The duty cycle of the second pump 52 refers to the ratio of the period during which the second pump 52 is operating within a given cycle. In other words, the duty cycle of the second pump 52 refers to the proportion of the total period during which the second pump 52 is operating within the period for which the duty cycle is calculated. For example, consider a case where the period for which the duty cycle of the second pump 52 is calculated is X (seconds), and within that period, the second pump 52 is stopped for Y (seconds). In this case, the duty cycle (%) of the second pump 52 can be calculated as {(XY) / X} × 100. Figure 4 is a graph showing the relationship between the time in the first period and the flow rate of the gas flowing through the second pump 52. The main control unit 811 controls the application of voltage to the second pump 52 during the operating period (reference numeral 402) and does not apply voltage to the second pump 52 during the stopping period (reference numeral 403) within one cycle (reference numeral 401) of the first period. One cycle may be, for example, 1 second. As a result, the second pump 52 operates during the operating period (reference numeral 402) and stops during the stopping period (reference numeral 403). Therefore, as shown in Figure 4, the flow rate of gas flowing through the second pump 52 increases during the operating period (reference numeral 402) and decreases during the stopping period (reference numeral 403). In this way, the second pump 52 operates with a predetermined duty cycle during the first period.

[0042] According to the above configuration, during the first period, the second pump 52 supplies the first gas to the sensor 31 while operating intermittently. The first gas is supplied to the sensor 31 only during the operating period when the second pump 52 is running, and not during the stop period when the second pump 52 is not operating. In this way, the control unit 81 can control the flow rate of the first gas supplied by the second pump 52 to the sensor 31 during the first period by intermittently operating the second pump 52. According to the above configuration, the amount of first gas supplied to the sensor 31 can be controlled without complicating the circuit of the detection device 1.

[0043] Furthermore, in the detection device 1 according to this disclosure, the first period includes a stop period during which the second pump 52 does not operate. As a result, the detection device 1 according to this disclosure can reduce the amount of first gas supplied to the sensor 31 during the first period compared to a configuration in which the second pump 52 operates throughout the entire first period.

[0044] As described above, the above configuration makes it possible to reduce the amount of first gas required for detection. Furthermore, since the amount of first gas supplied to the sensor 31 is reduced, it is possible to miniaturize the storage unit 20 that stores the first gas. Also, as mentioned above, the storage unit 20 is located inside the housing 90 of the detection device 1. As the storage unit 20 is miniaturized, it is also possible to miniaturize the housing 90 that houses the storage unit 20 inside.

[0045] To reduce the amount of first gas required, it is conceivable to shorten the first period. However, if the first period is shortened compared to the conventional method, there may not be enough time for the sensor 31 and the gas contained in the first gas to react, potentially resulting in an insufficient signal waveform. In contrast, the detection device 1 according to this embodiment allows the amount of first gas supplied to the sensor 31 during the first period to be sufficient to obtain a signal waveform, while reducing the amount of first gas supplied during the first period. Therefore, with the above configuration, it is possible to obtain a signal waveform sufficient for detection while reducing the amount of first gas required.

[0046] The main control unit 811 may operate the second pump 52 at a duty cycle of 50% or less during the first period. With the above configuration, the amount of the first gas used for detection can be reduced to less than half of the amount used when the duty cycle is 100%.

[0047] The duty cycle may be, for example, 50%. The main control unit 811 may operate the second pump 52 at a rate of 50% per second during the first period. In this case, as shown in Figure 4, one cycle (reference numeral 401) is 1 second, and the operating period (reference numeral 402) and stop period (reference numeral 403) per second are 500 milliseconds each. During the first period, the second pump 52 supplies the first gas to the sensor 31 while alternately switching between an operating state and a stopped state every 500 milliseconds. The first gas in the storage unit 20 is supplied from the storage unit 20 to the sensor 31 by the operation of the second pump 52 during the operating period. The duty cycle is not limited to 50%. For example, the duty cycle may be 40%, 20%, or 10%. Also, one cycle (reference numeral 401) is not limited to 1 second. For example, one cycle (reference numeral 401) may be 0.5 seconds or 2 seconds.

[0048] The operating period of the second pump 52 when the duty cycle is 50% is half the operating period of the second pump 52 when the duty cycle is 100%. Therefore, by setting the duty cycle of the second pump 52 to 50%, the amount of the first gas supplied to the sensor 31 during the first period can be reduced to less than half of the amount supplied when the duty cycle is 100%.

[0049] The main control unit 811 may operate the second pump 52 by applying a control voltage to the oscillation circuit 522. During the first period, the main control unit 811 applies a control voltage to the oscillation circuit 522 during the operating period and does not apply a control voltage to the oscillation circuit 522 during the stop period. The main control unit 811 switches between a state in which a control voltage is applied to the oscillation circuit 522 and a state in which it is not applied by switching the power supply 521 that applies the control voltage to the oscillation circuit 522 on and off. During the operating period, the oscillation circuit 522 outputs a signal to the second pump 52 to operate the second pump 52 at a predetermined oscillation frequency. On the other hand, during the stop period, the oscillation circuit 522 does not output a signal. As a result, the second pump 52 operates during the operating period and stops during the stop period.

[0050] According to the above configuration, the invention of this disclosure can be applied to a detection device equipped with an AC pump. The main control unit 811 can provide a stop period by performing control that does not apply a control voltage to the oscillation circuit 522 during the first period.

[0051] For example, if the main control unit 811 operates the second pump 52 with a 50% duty cycle, the main control unit 811 applies a control voltage to the oscillator circuit 522 continuously for 500 milliseconds out of one second, and then controls the oscillator circuit 522 so that no control voltage is applied for the next 500 milliseconds. Since the oscillator circuit 522 outputs a signal to the second pump 52 only during the period when the control voltage is applied, the second pump 52 operates for 500 milliseconds out of one second and stops for the next 500 milliseconds. As a result, the second pump 52 operates with a 50% duty cycle during the first period.

[0052] The switching frequency between the operating period and the stop period may be smaller than (or lower than) the oscillation frequency of the oscillator circuit 522. In other words, the operating period and the stop period may be switched at a frequency lower than the frequency at which the oscillator circuit 522 outputs a signal. Figure 5 is a graph showing the correspondence between the switching frequency between the operating period and the stop period and the oscillation frequency of the oscillator circuit 522. The graph indicated by reference numeral 501 shows the relationship between time and the control voltage applied by the main control unit 811 to the oscillator circuit 522. The graph indicated by reference numeral 502 shows the relationship between time and the signal that the oscillator circuit 522 can output. Figure 5 illustrates a configuration in which the oscillator circuit 522 can output a signal at an oscillation frequency of 50 Hz.

[0053] In the example shown in Figure 5, the main control unit 811 does not apply a control voltage to the oscillation circuit 522 from 0 seconds to 0.5 seconds, and applies a control voltage to the oscillation circuit 522 from 0.5 seconds to 1 second. In the example shown in Figure 5, the period from 0 seconds to 0.5 seconds corresponds to the stop period, and the period from 0.5 seconds to 1 second corresponds to the operation period. The oscillation circuit 522 outputs a signal to the second pump 52 at an oscillation frequency of 50 Hz from 0.5 seconds to 1 second. As a result, the second pump 52 operates at 50 Hz during the operation period. Thus, the switching between the operation period and the stop period may be performed every 500 milliseconds. In this case, the switching frequency between the operation period and the stop period will be smaller than the oscillation frequency of the oscillation circuit 522.

[0054] According to the above configuration, during the first period, the operating state and the stopped state of the second pump 52 are switched at a frequency lower than the frequency at which the oscillation circuit 522 oscillates a signal. This reduces the possibility that the second pump 52 may not operate during the operating period or may continue to operate during the stopped period.

[0055] For example, the switching frequency between the operating period and the stopping period may be 1 time / second or more. In other words, the operating period and the stopping period may be switched at least once per second during the first period. If the frequency of switching between the operating period and the stopping period is low, the duration of each stopping period will be long. In this case, the signal strength output by the sensor 31 may not be stable during the first period, and the signal waveform may be distorted. If the signal waveform is distorted, the estimation result for the specific gas in the estimation unit 813 may be inaccurate. With the above configuration, the first gas is supplied to the sensor 31 at a flow rate that allows for sufficient detection of the specific gas. Flow rate means the amount of gas that flows per unit time. This reduces the possibility that the estimation result by the estimation unit 813 may be inaccurate. The acquisition unit 812 acquires the signal output from the sensor 31. The acquisition unit 812 outputs data showing the signal waveform based on the signal acquired from the sensor 31 during the first period to the estimation unit 813.

[0056] Figure 6 is a graph showing an example of signal waveforms based on signals acquired from three types of sensors 31 when the second pump 52 is operated under the same conditions as in the first period. Figure 7 is a graph showing an example of signal waveforms when two different types of sensors 31 are used, under the same conditions as in the example shown in Figure 6, but different from the signal waveforms obtained in Figure 6. In the examples shown in Figures 6 and 7, the first gas is supplied to the sensors 31 twice.

[0057] In Figures 6 and 7, the graphs indicated by reference numerals 601-603 and 701-702 show waveforms based on signals obtained from each of the multiple sensors 31 when the second pump 52 is operated at a 100% duty cycle. In Figures 6 and 7, the graphs indicated by reference numerals 604-606 and 703-704 show waveforms based on signals obtained from each of the same multiple sensors 31 when the second pump 52 is operated at a 50% duty cycle. Also in Figures 6 and 7, the pairs of reference numerals 601 and 604, 602 and 605, 603 and 606, 701 and 703, and 702 and 704 each show waveforms obtained from the same type of sensor 31. As shown in Figures 6 and 7, the signal waveform when the second pump 52 is operated at a 50% duty cycle has a smaller amplitude than the signal waveform when the second pump 52 is operated at a 100% duty cycle.

[0058] In detection device 1, the second pump 52 is operated at a predetermined duty cycle of less than 100%. Therefore, the amount of first gas supplied to sensor 31 is less compared to when the second pump 52 is operated at a 100% duty cycle. Consequently, the signal waveform acquired by acquisition unit 812 in detection device 1 has a smaller amplitude than the signal waveform obtained when the second pump 52 is operated at a 100% duty cycle.

[0059] Furthermore, the series of detections may include a period for purging any remaining first gas in the sensor chamber 30 after the first gas has been supplied to the sensor 31. For example, the series of detections may further include a third period after the first period in which a second gas, different from the first gas, is supplied to the sensor 31.

[0060] The second pump 52 may supply a second gas, different from the first gas, to the sensor 31 during the third period, which is later than the first period. The main control unit 811 may also operate the second pump 52 at a 100% duty cycle during the third period. Specifically, the main control unit 811 controls the valve 60 to operate the second pump 52. As a result, the second gas is drawn in through the second opening 42. The second gas drawn in through the second opening 42 is supplied to the sensor 31 through the flow path 70 and discharged from the third opening 43. This purges any first gas that remained near the sensor 31, for example, in the sensor chamber 30. As the first gas is discharged from the third opening 43 along with the second gas, the signal value output by the sensor 31 decreases.

[0061] Figure 8 is a graph showing an example of signal waveforms based on signals acquired from the same three types of sensors 31 as in the example shown in Figure 6, during a detection period including the first and third periods. Figure 9 is a graph showing an example of signal waveforms based on signals acquired from the types of sensors 31 used when obtaining the waveforms shown by reference numerals 701 and 703 in Figure 7, under the same conditions as in the example shown in Figure 8. The graphs indicated by reference numerals 801 to 803 show signal waveforms based on signals obtained from each of the same three types of sensors 31 as in the example shown in Figure 6, when the second pump 52 is operated at a 50% duty cycle in the first period and then at a 100% duty cycle in the third period. The graph indicated by reference numeral 901 shows signal waveforms based on signals obtained from the types of sensors 31 corresponding to reference numerals 701 and 703 in Figure 7, when the second pump 52 is operated at a 50% duty cycle in the first period and then at a 100% duty cycle in the third period. The graphs shown by reference numerals 804 to 806 show signal waveforms based on signals obtained from each of the three types of sensors 31, the same as in the example shown in Figure 6, when the second pump 52 is operated with a 50% duty cycle during the first and third periods. The graph shown by reference numeral 902 shows signal waveforms based on signals obtained from sensors 31 of the types corresponding to reference numerals 701 and 703 in Figure 7, when the second pump 52 is operated with a 50% duty cycle during the first and third periods.

[0062] As shown by reference numerals 804-806 and 902 in Figures 8 and 9, if the second pump 52 is operated at a 50% duty cycle during the third period, the signal value of sensor 31 may not decrease sufficiently. This is thought to be because the first gas supplied to sensor 31 is not sufficiently purged and remains. If the first gas remains near sensor 31, it may affect subsequent detections and reduce the accuracy of detection. In contrast, as shown by reference numerals 801-803 and 901 in Figures 8 and 9, if the second pump 52 is operated at a 100% duty cycle during the third period, the signal value of sensor 31 can be sufficiently reduced.

[0063] Therefore, according to the above configuration, the second gas is supplied to the sensor 31 in the third period following the first period, and in the third period, the first gas supplied to the sensor 31 in the first period is purged. In addition, since the second pump 52 operates at a 100% duty cycle in the third period, the first gas is purged more reliably. This reduces the possibility of a decrease in the sensitivity of the sensor 31 in the next detection after a series of detections have been completed.

[0064] In the third period, it is sufficient for the first gas remaining in the sensor chamber 30 to be sufficiently removed. For example, the third period may be 120 seconds. During the third period, the second gas is drawn in from the second opening 42 and then supplied to the sensor 31 without passing through the storage unit 20. Therefore, even if a long time is set for the third period, and the second pump 52 is operated at a high duty cycle during the third period, no gas will be stored in the storage unit 20. Thus, the settings for the third period do not affect the miniaturization of the storage unit 20.

[0065] Furthermore, the series of detections may include a fourth period after the third period for cleaning the storage unit 20. During the fourth period, the main control unit 811 operates the second pump 52 to supply the second gas to the storage unit 20, and then discharges the gas in the storage unit 20 through the third opening 43. This purges any remaining first gas in the storage unit 20. The detection device 1 may be able to start the next storage period after the fourth period.

[0066] The estimation unit 813 estimates the type or concentration of a specific gas contained in the first gas based on the signal output by the sensor 31. The estimation unit 813 may be capable of detecting both the type and concentration of the specific gas. The estimation unit 813 acquires data showing the signal waveform from the acquisition unit 812. The estimation unit 813 may use the acquired signal waveform as input data and estimate the type or concentration of the specific gas using the estimation model M. If signal waveforms are acquired from each of the multiple sensors 31, the estimation unit 813 may use all of the acquired signal waveforms as input data.

[0067] Furthermore, the estimation unit 813 may output information indicating the detection result. For example, the estimation unit 813 may transmit information indicating the detection result to an external device capable of estimating information regarding the subject's intestinal environment based on the type or concentration of a specific gas.

[0068] In detection device 1, the second pump 52 is operated at a predetermined duty cycle of less than 100%, resulting in a smaller amplitude of the signal waveform compared to when the second pump 52 is operated at a 100% duty cycle. Conventional estimation models learn based on the signal waveform obtained when the second pump 52 is operated at a 100% duty cycle. Therefore, even if the signal waveform acquired by detection device 1 according to the present invention is input to a conventional estimation model, it is not possible to output an accurate estimation result.

[0069] Here, the estimation model M is trained based on the signal waveform when the second pump 52 is operated at a predetermined duty cycle. By using the estimation model M, the estimation unit 813 can accurately estimate the type or concentration of a specific gas contained in the first gas, even in the detection device 1 of this invention, in which a smaller amount of the first gas is supplied to the sensor 31 than in conventional devices.

[0070] In the embodiments described above, the detection device 1 is illustrated as a single device, but it is not limited to this configuration. For example, the detection device 1 may consist of a first device installed in the toilet bowl, comprising a main control unit 811 and an acquisition unit 812, and the configurations shown in Figure 1, and a second device comprising an estimation unit 813 that stores an estimation model M. The first device and the second device may be connected in a communicative manner. In this case, the second device may be installed outside the toilet room. When the acquisition unit 812 of the first device acquires a signal output from the sensor 31, it may transmit information including the signal to the second device. The estimation unit 813 of the second device may perform estimations regarding a specific gas based on this information. With this configuration, it is not necessary to perform complex estimation processing in the first device installed in the toilet bowl, and therefore the configuration of the control unit of the first device can be simplified.

[0071] [Embodiment 2] Other embodiments of this disclosure are described below. For the sake of clarity, components having the same function as those described in the above embodiments are denoted by the same reference numerals, and their descriptions are not repeated.

[0072] In Embodiment 1, an example was given in which a series of detections includes one period during which the first gas is supplied to the sensor 31. However, in a series of detections, there may be multiple periods during which the first gas is supplied to the sensor 31. For example, a series of detections may further include a second period after the first period during which the first gas is supplied to the sensor 31.

[0073] Figure 10 is a block diagram showing the configuration of detection device 1A according to Embodiment 2 of the present disclosure. As shown in Figure 10, detection device 1A differs from detection device 1 in that it includes a control unit 81A and a storage unit 82A instead of a control unit 81 and a storage unit 82. The control unit 81A includes a main control unit 811A, an acquisition unit 812, and an estimation unit 813A. The storage unit 82A stores the estimated model MA.

[0074] The estimation model MA is used to estimate the type and concentration of a specific gas based on the signal waveform obtained from the sensor 31. The estimation model MA is a trained estimation model that has been trained using a dataset containing multiple pairs of data showing signal waveforms as input data for training and information showing the type and concentration of a specific gas as training data.

[0075] The input data for training in the estimation model MA may be data showing the signal waveform obtained when gas is supplied to the sensor 31 with the same duty cycle as the operation duty cycle of the second pump 52 when supplying the first gas during the second period. In addition, information indicating the type and concentration of a specific gas contained in the gas supplied to the sensor 31 when acquiring the input data for training may be used as training data.

[0076] The main control unit 811A operates the second pump 52 in the first period, and then operates the second pump 52 again in the second period. The second pump 52 supplies the first gas to the sensor 31 in the second period, which is later than the first period. In addition, the main control unit 811A operates the second pump 52 in the second period with a larger duty cycle than in the first period. The second period may be the same length as the first period or longer. For example, the first period may be 60 seconds and the second period may be 120 seconds.

[0077] The estimation unit 813A detects the type or concentration of a specific gas based on the signal output from the sensor 31 during the second period. Alternatively, the estimation unit 813A may estimate the type or concentration of a specific gas without using the signal output during the first period.

[0078] By pre-exposing the sensor 31 to a specific gas during the first period, prior to the second period, the baseline signal value of the sensor 31 output during the second period can be standardized. This process of reacting the sensor 31 to a specific gas is also referred to as "familiarizing" it. As described above, the detection device 1A can perform more accurate estimations regarding the specific gas by familiarizing the sensor 31 during the first period and using the signal from the second period.

[0079] The main control unit 811A may operate the second pump 52 with a duty cycle of 50% or less during the first period. Furthermore, the main control unit 811A may operate the second pump 52 with a duty cycle of 100% during the second period.

[0080] In this embodiment, the series of detections may include a third period in addition to the first and second periods. The third period may be provided after the first period and after the second period. The lengths of the third period after the first period and the third period after the second period may be the same or different. For example, a 120-second third period may be provided after a 60-second first period and a 120-second second period. The series of detections may also include a fourth period. If the series of detections includes a fourth period, the fourth period may be a period after the third period following the second period.

[0081] Figure 11 is a graph showing the relationship between the output voltage of the sensor 31 and the elapsed time of the detection period in the detection device 1A according to this embodiment. As an example, Figure 11 shows a graph obtained when the second pump 52 operates with a duty cycle of 50% in the first period (reference numeral 1103) and the second pump 52 operates with a duty cycle of 100% in the second period (reference numeral 1104). As shown in Figure 11, in the detection device 1A, the signal waveform obtained from the sensor 31 during the detection period has two waves, indicated by reference numerals 1101 and 1102. First, in the first period (reference numeral 1103), the second pump 52 operates with a predetermined duty cycle and the first gas is supplied to the sensor 31, and then in the third period (reference numeral 1105), the first gas is purged, resulting in the waveform indicated by reference numeral 1101. Subsequently, in the second period (reference numeral 1104), the second pump 52 operates with a larger duty cycle than in the first period to supply the first gas to the sensor 31. Then, in the third period (reference numeral 1106), the first gas is purged, resulting in the waveform shown by reference numeral 1102. The estimation unit 813A may perform estimation using the signal showing the second waveform (reference numeral 1102).

[0082] As shown in Figure 11, the voltage value of sensor 31 rises during the first period and then decreases during the third period. This allows the baseline voltage value of sensor 31 during the second period of this detection to be aligned with the baseline of other detections.

[0083] In conventional detection devices, the signal waveform obtained when the second pump 52 is operated at a 100% duty cycle was used as input data for learning. With the above configuration, in the second period, the same amount of first gas as when detection occurs in conventional detection devices is supplied to the sensor 31. Therefore, with the above configuration, the estimation unit 813 can perform estimations regarding a specific gas using the estimation model that has been used conventionally. In addition, in the first period, the second pump 52 operates at a duty cycle of 50% or less. Therefore, the amount of first gas used in a series of detections can be reduced compared to operating the second pump 52 at a 100% duty cycle in both the first and second periods.

[0084] In this embodiment, the configuration in which the main control unit 811A operates the second pump 52 with a duty cycle of 100% during the second period has been described as an example, but the embodiment is not limited to this. The main control unit 811A may also operate the second pump 52 with a duty cycle of less than 100% during the second period. In this case, the estimation unit 813A performs estimation using the estimation model MA, which has been learned as input data for learning, based on the signal waveform when the second pump 52 is operated with a duty cycle of less than 100%. For example, the main control unit 811A may operate the second pump 52 with the same duty cycle as in the first period during the second period. In this case, the estimation unit 813A may perform estimation using the estimation model M according to Embodiment 1.

[0085] [Embodiment 3] In Embodiment 1, a configuration in which the second pump 52 is an AC pump was given as an example, but the second pump 52 is not limited to an AC pump. In this embodiment, a configuration in which the second pump 52 is a so-called DC pump will be used as an example for explanation.

[0086] Figure 12 is a block diagram showing the configuration of detection device 1B according to Embodiment 3 of the present disclosure. As shown in Figure 12, detection device 1B differs from detection device 1 in that it includes a second pump 52B, a control unit 81B, and a power supply 521B (pump power supply) instead of the second pump 52, control unit 81, and power supply 521, and does not include an oscillation circuit 522. Also, control unit 81B differs from control unit 81 in that it includes a main control unit 811B instead of the main control unit 811. When a control voltage is supplied by the control of the main control unit 811B, power supply 521B applies drive power to the second pump 52B. The second pump 52B is a so-called DC pump and operates during the period when drive power is applied from power supply 521B. In this way, the main control unit 811B can operate the second pump 52B by performing control to apply a control voltage to power supply 521B.

[0087] The main control unit 811B applies a control voltage to the power supply 521B at a predetermined duty cycle. When the control voltage is applied by the main control unit 811B, the power supply 521B supplies power to the second pump 52B. As a result, the second pump 52B operates at a predetermined duty cycle. For example, if the predetermined duty cycle is 50%, the main control unit 811B applies a control voltage to the power supply 521B at a 50% duty cycle. As a result, the second pump 52B operates at a 50% duty cycle. With the above configuration, the invention according to this disclosure can be applied to a detection device equipped with a DC pump.

[0088] [Examples of implementation using software] The functions of detection devices 1, 1A, and 1B (hereinafter referred to as "devices") can be realized by programs that cause computers to function as devices, and by programs that cause computers to function as each control block of the devices (particularly each part included in control units 81, 81A, and 81B).

[0089] In this case, the device includes a computer having at least one control device (e.g., a processor) and at least one storage device (e.g., memory) as hardware for executing the program. By executing the program using this control device and storage device, the functions described in each of the embodiments are realized.

[0090] The above program may be recorded on one or more computer-readable recording media, not temporary ones. These recording media may or may not be provided by the above device. In the latter case, the program may be supplied to the above device via any wired or wireless transmission medium.

[0091] Furthermore, some or all of the functions of each of the above control blocks can also be implemented by logic circuits. For example, an integrated circuit in which logic circuits functioning as each of the above control blocks are formed is also included in the scope of this disclosure. In addition, it is also possible to implement the functions of each of the above control blocks by, for example, a quantum computer.

[0092] Furthermore, each process described in the above embodiments may be performed by AI (Artificial Intelligence). In this case, the AI ​​may operate on the control device described above, or it may operate on other devices (for example, an edge computer or a cloud server).

[0093] The inventions described in this disclosure have been explained above based on the drawings and embodiments. However, the inventions described in this disclosure are not limited to the embodiments described above. That is, the inventions described in this disclosure can be modified in various ways within the scope shown in this disclosure, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the inventions described in this disclosure. In other words, it should be noted that it is easy for those skilled in the art to make various modifications or alterations based on this disclosure. Furthermore, it should be noted that these modifications or alterations are included in the scope of this disclosure.

[0094] 〔summary〕 A detection device according to Embodiment 1 of the present disclosure comprises a sensor that outputs a signal corresponding to the gas contained in a first gas supplied during a first period, a storage unit that stores the first gas supplied to the sensor, a pump that supplies the first gas stored in the storage unit to the sensor, and a control unit that controls the pump, wherein the first period includes a plurality of operating periods during which the control unit operates the pump and at least one stopping period during which the control unit stops the pump, and the stopping period is provided between the plurality of operating periods.

[0095] In the detection device according to embodiment 2 of the present disclosure, in embodiment 1, the control unit may operate the pump with a duty cycle of 50% or less during the first period.

[0096] The detection device according to embodiment 3 of the present disclosure may have an estimation unit that estimates the type or concentration of the gas contained in the first gas based on the signal output by the sensor, in embodiment 1 or 2 above.

[0097] In the detection device according to embodiment 4 of the present disclosure, in embodiment 3, the pump supplies the first gas to the sensor in a second period later than the first period, the control unit operates the pump in the second period with a larger duty cycle than in the first period, and the estimation unit estimates the type or concentration of the gas based on the signal output in the second period.

[0098] In the detection device according to aspect 5 of the present disclosure, in aspect 4, the estimation unit may estimate the type or concentration of the gas without using the signal output during the first period.

[0099] In the detection device according to embodiment 6 of the present disclosure, in embodiment 4 or 5, the control unit may operate the pump with a duty cycle of 50% or less during the first period and operate the pump with a duty cycle of 100% during the second period.

[0100] In the detection device according to embodiment 7 of the present disclosure, in any of embodiments 1 to 6, the pump supplies a second gas different from the first gas to the sensor during a third period later than the first period, and the control unit may operate the pump at a duty cycle of 100% during the third period.

[0101] The detection device according to embodiment 8 of the present disclosure includes an oscillation circuit that outputs a signal for operating the pump at a predetermined oscillation frequency in any of embodiments 1 to 7, and the control unit may operate the pump by performing control by applying a control voltage to the oscillation circuit.

[0102] In the detection device according to embodiment 9 of the present disclosure, in embodiment 8, the switching frequency between the operating period and the stopping period may be smaller than the oscillation frequency of the oscillation circuit.

[0103] The detection device according to embodiment 10 of the present disclosure includes a pump power supply that supplies power to the pump in any of embodiments 1 to 7, and the control unit may operate the pump by performing control that applies a control voltage to the pump power supply.

[0104] In the detection device according to embodiment 11 of the present disclosure, in any of embodiments 1 to 10, the switching frequency between the operating period and the stopping period may be 1 time / second or more.

[0105] The detection device according to embodiment 12 of the present disclosure may include a housing in which the storage unit and the sensor are located inside, as in any of embodiments 1 to 11 above. [Explanation of symbols]

[0106] 1, 1A, 1B detection device 20 Storage section 302 Operating period 303 Downtime 31 Sensors 52, 52B Second pump (pump) 521B Power supply (pump power supply) 522 Oscillator Circuit 811, 811B Main Control Unit (Control Unit) 813 Estimation Department 90 cabinets

Claims

1. A sensor that outputs a signal corresponding to the gas contained in the first gas supplied during the first period, A storage unit for storing the first gas supplied to the sensor, A pump that supplies the first gas stored in the storage section to the sensor, A control unit that controls the pump, Equipped with, The first period includes a plurality of operating periods during which the control unit operates the pump, and at least one stopping period during which the control unit stops the pump. The aforementioned stop period is provided between the plurality of aforementioned operating periods. Detection device.

2. The control unit operates the pump with a duty cycle of 50% or less during the first period. The detection device according to claim 1.

3. The system has an estimation unit that estimates the type or concentration of the gas contained in the first gas based on the signal output by the sensor. The detection device according to claim 1.

4. The pump supplies the first gas to the sensor during a second period that is later than the first period. The control unit, During the second period, the pump is operated with a duty cycle larger than that of the first period. The estimation unit estimates the type or concentration of the gas based on the signal output during the second period. The detection device according to claim 3.

5. The detection device according to claim 4, wherein the estimation unit estimates the type or concentration of the gas without using the signal output during the first period.

6. The control unit, During the first period, the pump is operated with a duty cycle of 50% or less. During the second period, the pump is operated at a duty cycle of 100%. The detection device according to claim 4.

7. The pump supplies a second gas, different from the first gas, to the sensor during a third period that follows the first period. The control unit operates the pump at a duty cycle of 100% during the third period. The detection device according to claim 1.

8. The system includes an oscillator circuit that outputs a signal to operate the pump at a predetermined oscillation frequency, The control unit operates the pump by applying a control voltage to the oscillation circuit. The detection device according to claim 1.

9. The switching frequency between the operating period and the stopping period is smaller than the oscillation frequency of the oscillation circuit. The detection device according to claim 8.

10. The pump is equipped with a pump power supply that provides power to drive the pump, The control unit operates the pump by applying a control voltage to the pump power supply. The detection device according to claim 1.

11. The switching frequency between the operating period and the stopping period is 1 time / second or more. The detection device according to claim 1.

12. The housing comprises the storage section and the sensor located inside. The detection device according to claim 1.

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