Faucet equipment

Abstract

The present invention aims to provide a faucet that uses a capacitance sensor as a proximity sensor while simultaneously measuring the ambient temperature. [Solution] The faucet comprises a faucet body equipped with a spout, a control unit that switches between discharging and shutting off water from the spout, and a capacitance sensor that detects a human body, and is characterized by detecting temperature changes by changes in capacitance when the mode is in a normal standby state.

Description

[Technical Field]

[0001] The present invention relates to a faucet device, and more particularly to a faucet device that enables contactless operation using a capacitive sensor. [Background technology]

[0002] Conventionally, water faucet devices that detect air temperature and perform various controls have been known. These types of water faucet devices require a built-in temperature sensor (see Patent Documents 1 and 2).

[0003] Furthermore, there is a known water faucet device that uses a capacitance sensor to detect a human body and control the water discharge or stoppage, but this type of water faucet device does not detect temperature (Patent Document 3). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 08-234849 [Patent Document 2] Japanese Patent Publication No. 08-284224 [Patent Document 3] Patent No. 7479736 [Overview of the Initiative] [Problem to be solved by the invention]

[0005] The present invention aims to provide a faucet that uses a capacitance sensor as a proximity sensor while simultaneously measuring the ambient temperature. [Means for solving the problem]

[0006] To achieve the above object, according to the invention of claim 1, a faucet comprises a faucet body with a water outlet, a control unit that switches between discharging water from the outlet and stopping water, and a capacitance sensor that detects a human body, and detects temperature changes based on changes in capacitance in the normal standby state. This configuration makes it possible to measure ambient temperature changes using the capacitance sensor for human body detection without using a separate temperature sensor, thereby improving usability and design.

[0007] Furthermore, in the present invention, it is preferable to periodically acquire the capacitance in a normal standby state, remove noise through a first-order differential IIR filter, and then detect temperature changes. Although the capacitance value fluctuates significantly due to the influence of noise, by configuring it in this way and passing it through a first-order differential IIR filter, it becomes possible to remove the influence of noise with a small calculation load and perform stable temperature detection, improving usability.

[0008] Furthermore, in the present invention, it is preferable that, in the normal standby state, temperature changes are detected at a second sampling period that is longer than the sampling period for detecting a human body. Temperature changes around the faucet occur on the order of minutes, even at the most rapid rate. This is significantly different from the speed of change required for detecting user contact, which occurs on the order of seconds. Therefore, in terms of data processing load, it is desirable to set the sampling period for detecting temperature changes longer than the sampling period for detecting user contact. This allows the faucet to be operated with an inexpensive data processing system, improving usability.

[0009] Furthermore, in the present invention, it is preferable to provide a calibration mode that correlates the capacitance at that time with the temperature around the faucet device when it is in a normal standby state. By installing the faucet and leaving it for a while so that it can adapt to the temperature of the surrounding space, and then performing a calibration operation to correlate the capacitance at that time with the actual temperature, the accuracy of temperature measurement can be greatly improved.

[0010] In addition, in the present invention, it is preferable to stop the temperature change sampling process when water discharge begins and resume the temperature change sampling process a certain time after water discharge ends. Because the temperature of the faucet body, which serves as an electrode, changes depending on the temperature of the running water while water is being discharged, the temperature detected during this time may differ from the actual ambient temperature. Therefore, by stopping the temperature detection sampling while water is being discharged, stable temperature detection can be performed, improving usability.

[0011] Furthermore, in the present invention, it is preferable to have a means for switching between hot and cold water discharge, and automatically switch to either hot water mode or cold water mode after a certain time has passed since water discharge has ended, depending on the temperature detection situation. Since the influence of the temperature of the running water remains immediately after water discharge has ended, temperature detection can be started after a certain time has passed for the water to adapt to the ambient temperature, allowing stable temperature detection. By switching the water discharge temperature based on the detection results, it is possible to supply water to the user at the desired comfortable temperature, improving usability.

[0012] In addition, in the present invention, it is preferable to change the discharged water temperature according to the temperature detection status. By configuring in this way, the heating temperature of the heat source, particularly the hot water storage heater, can be changed according to the temperature around the faucet, so not only can water be discharged at a temperature that is always suitable for the user, but also there is no need to store hot water at an unnecessary temperature, which contributes to power saving and improves usability. [Effects of the Invention]

[0013] According to the present invention, there is an effect of improving the usability of a water faucet device that detects a human body using a capacitance sensor. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a configuration diagram of the present invention. [Figure 2] 1 is a graph showing the temperature change of capacitance of the present invention. [Figure 3] 1 is a graph showing the temperature change of capacitance of the present invention. [Figure 4] This graph shows the time-series temperature change of the capacitance of the present invention. [Figure 5] This is a graph showing the time-series temperature change of the capacitance of the present invention. [Figure 6] This is a graph showing the time-series temperature change of the capacitance of the present invention. [Figure 7] This is a graph showing the time-series temperature change of the capacitance of the present invention. [Figure 8] This is a graph showing the time-series temperature change of the capacitance of the present invention. [Figure 9] This is a timing chart diagram of the present invention. [Figure 10] FIG. 1 is a flow chart diagram of the present invention. [Figure 11] This is a graph showing the annual temperature change and control timing of the present invention. [Figure 12] FIG. 1 is a configuration diagram of the present invention. [Figure 13] FIG. 1 is a flow chart diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0015] By constructing the faucet body from metal and placing a material with a high dielectric constant (let's call it material A) between it and the grounding part, the capacitance of this material can be measured. Furthermore, when a person touches the faucet body in this state, the capacitance between the faucet body and the mounting part becomes dominated by the person, whose dielectric constant is lower than that of material A, making it possible to distinguish whether or not the person is touching the faucet body. The configuration of this faucet is shown in Figure 1. As shown in Figure 1, an object A14 is sandwiched between the faucet body 10 and a ground surface such as a counter 18, the faucet body serves as an electrode, and a detection unit 22 is provided in a controller 20 housed separately within the counter 18, etc., to detect the capacitance. Hot water pipe 30 and cold water pipe 40 are connected to the faucet body 10; these two pipes feed water into an SMA thermovalve 50, where it is adjusted to a desired temperature suitable for hand washing before being discharged from the faucet body 10. The water pipe 40 also has a bypass flow path 44 that does not feed water into the SMA thermovalve 50, and this bypass flow path 44 is also connected to the faucet body. Solenoid valves A32 and B42 are located after the water passes through the SMA thermovalve 50 and in the bypass flow path 44, respectively. In this way, by opening solenoid valve A32 and closing solenoid valve B42, it is possible to dispense water at a temperature that is a mixture of hot and cold water (referred to here as hot water mode), and by closing solenoid valve A32 and opening solenoid valve B42, it is possible to dispense water at the temperature of the connected water itself (referred to here as cold water mode). With this configuration, by opening solenoid valve A32 or solenoid valve B42 in response to a change in capacitance when a person touches faucet body 10, it is possible to dispense water at the desired temperature.

[0016] Furthermore, when material A14 is resin, its dielectric constant changes with temperature. Therefore, by detecting the capacitance when no human body is in contact with the faucet, the temperature around the faucet can be estimated. This eliminates the need to install a separate temperature sensor, improving the usability and design of the faucet. Furthermore, the accuracy of temperature measurement can be greatly improved by installing the faucet and leaving it for a while to allow it to adapt to the temperature of the surrounding space, and then performing a calibration process to correlate the capacitance at that time with the actual temperature.The accuracy of temperature measurement can also be greatly improved by using a material with a higher temperature dependency of the dielectric constant of material A14. [Examples]

[0017] Figure 2 shows the temperature change in capacitance of the faucet body when there is no variation in values ​​due to noise. As the temperature rises, the detected capacitance tends to decrease. By utilizing this tendency, it is possible to infer the ambient temperature of the faucet at that time based on the capacitance value. However, as shown in Figure 3, the actually measured capacitance value varies due to the influence of various noises, so it is desirable to obtain the capacitance data through a noise reduction filter. There are various types of noise removal filters, but by using a first-order differential IIR filter such as the one shown below, it is possible to effectively remove noise associated with time changes, as in this case, with as little computational load as possible. Cf(k)=(1-α)×Cf(k-1)+α×C(k) … (1) Here, the filtered capacitance value Cf(k), the measured capacitance value C(k), and the filter value α, k, are the sampling timings of the time series, with the current value being k and the value one timing before being k-1.

[0018] Figure 4 shows the time series data for C(k). The ambient temperature changes over time, and the capacitance value changes accordingly. However, the value fluctuates greatly due to the influence of electrical noise, making it difficult to accurately determine the current temperature. Therefore, by using the first-order differential IIR filter in equation (1) above, it is possible to accurately remove noise and obtain the desired capacitance value Cf(k), as shown in Figure 5. The filter value α here is 0.001, which accurately removes noise with almost no time delay, and based on this, the current temperature around the faucet can be determined.

[0019] Figure 6 is another data showing the change in capacitance due to temperature changes. The change in capacitance over a period of about 100 minutes ultimately represents the change in temperature over that period, but the values ​​vary greatly due to the influence of noise. The sampling period is 50 msec (this is called normal mode), and Figure 6 shows the result of noise removal with a filter value of 0.001. Because hand movements occur in units of less than a second, it is necessary to sample the change in capacitance at this frequency, but because the ambient temperature usually changes on the order of minutes or more when the device is not in use, there is no need to sample at this frequency. Figure 7 shows the data from Figure 5, acquired with a sampling period of 30 seconds. Figure 8 shows the results after noise removal using a filter value of 0.1. After a certain amount of time has passed since a human operation, the sampling period can be increased to reduce the data processing load (referred to here as standby mode). Even in this case, a first-order differential IIR filter can be used to accurately remove noise while measuring the ambient temperature of the faucet. If a human operates the faucet during standby mode, a slight decrease in response is expected only the first time. However, by switching to normal mode after that, human operation detection and temperature detection can be performed with the optimal computational load for each purpose, whether standby or normal. Furthermore, since the water temperature transfers heat to the faucet itself as water flows, potentially resulting in the faucet temperature being different from the outside air temperature, it is recommended that a certain amount of time has passed since the last water discharge before switching from normal mode to standby mode. This allows the faucet temperature to adapt to the ambient temperature, allowing for accurate measurement of the ambient temperature.

[0020] This switching can be performed at the following timings as shown in Figure 9. When human operation is detected from the standby mode when not in use, the faucet switches from standby mode to normal mode and starts dispensing water. If hot water, which is hotter than the ambient temperature, is dispensed at this time, the temperature of the faucet body will also rise as a result, and the capacitance will decrease. Even after dispensing water has stopped, the temperature will not be the same as the ambient temperature for a while, and will gradually adjust to the ambient temperature over a certain period of time, so the faucet remains in normal mode and temperature change sampling is not performed during this time. After a certain period of time has elapsed, the faucet switches from normal mode to standby mode, the sampling period is reduced, and temperature change sampling is performed.

[0021] Figure 10 is a flowchart showing the automatic transition to either hot water mode or cold water mode after a certain period of time has elapsed since the end of water discharge, depending on the temperature detection status. As shown in Figure 9, after a certain period of time has elapsed since the end of water discharge, if the capacitance Cf is below threshold B (which means that the ambient temperature around the faucet is below the threshold), and the setting to open solenoid valve A or solenoid valve B is set to cold water, then the setting is changed to open solenoid valve A and the standby mode continues. On the other hand, if the setting to open solenoid valve A or solenoid valve B is set to hot water, then the setting to open solenoid valve A is changed to open solenoid valve B and the standby mode continues. Furthermore, as shown in Figure 11, the discharge water temperature can be automatically changed according to annual temperature changes, making it possible to supply water to users at the desired comfortable temperature.

[0022] Figure 12 is a diagram illustrating the configuration for changing the heating temperature of the electric water heater 270 according to the detected capacitance value (ambient temperature around the faucet) in standby mode, and Figure 13 is a flowchart of the same configuration. This configuration allows the temperature of the heater 260 that supplies power to the electric water heater 270 to be changed according to the detected capacitance, and as a result, the heating temperature of the electric water heater 270 can be changed. This makes it possible to discharge water at the heated temperature according to the capacitance value by opening the solenoid valve 232. [Explanation of symbols]

[0023] 10…Faucet body 14...Substance A 18...Counter 20...Controller 22...Detection unit 30...Hot water piping 32...Solenoid valve A 40...Water piping 42...Solenoid valve B 44...Bypass flow path 50...SMA thermo valve 260...Heater 270...Electric water heater

Claims

1. A faucet body having a spout; a control unit for switching between discharging and stopping water from the water outlet; A capacitance sensor for detecting a human body is provided, and the mode is A water faucet device characterized in that it detects temperature changes based on changes in capacitance in a normal standby state.

2. 2. The water faucet device according to claim 1, wherein the capacitance in a normal standby state is periodically acquired, and noise is removed through a first-order differential IIR filter to detect temperature changes.

3. 3. The water faucet device according to claim 1, wherein in a normal standby state, temperature changes are detected at a second sampling period that is longer than the sampling period for detecting a human body.

4. 3. The water faucet device according to claim 1 or 2, further comprising a calibration mode for correlating the capacitance at that time with the temperature around the water faucet device in a normal standby state.

5. 3. The water faucet device according to claim 1, wherein the temperature change sampling process is stopped when water discharge starts, and the temperature change sampling process is resumed when a certain time has elapsed after water discharge ends.

6. A hot and cold water discharge switching means is provided, 3. The water faucet device according to claim 1, wherein the water faucet automatically switches to either the hot water mode or the cold water mode depending on the detected temperature after a certain time has elapsed since the water discharge ended.

7. Equipped with a water temperature adjustment unit that adjusts the water temperature, 3. The water faucet device according to claim 1, wherein the temperature of the discharged water is changed depending on the temperature detection state.

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