JP2014190139A - Automatic water faucet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an automatic water faucet which performs water discharge/cutoff control by exactly determining the approach of a user himself/herself and an object to be washed.SOLUTION: An automatic water faucet of this invention comprises: a water discharge part; a sensor part which receives a reflection wave signal of a radiated electric wave, mixes the received signal with a part of a transmission signal at a mixer part, generates a Doppler signal which is obtained through a filter circuit, and is arranged in the vicinity of the water discharge part; and a determination part which determines approach of an object to be detected on the basis of a frequency and a magnitude of the Doppler signal which is generated by the sensor part. The determination part determines whether or not the object to be detected is a user, or the object to be detected which is smaller than the user, furthermore, discriminates between the approach of the user to the vicinity of the water discharge part, and the approach of the object to be detected which is smaller than the user to the vicinity of the water discharge part, and performs the water discharge control of the water discharge part according to the determination result of the determination part.

Description

  The present invention relates to an automatic water faucet, and detects the approach of an object to be cleaned such as a human hand using a radio wave sensor such as a microwave when operating the automatic water faucet, and controls automatic water faucet. Regarding the stopper.

  Conventionally, automatic faucets that detect the presence of a user and automatically discharge and stop water have been widely used. Such automatic faucets are used in washstands, etc. For example, to wash dirty hands, just spit out the hand near the water discharger (spout, spout) and start water discharge. The water stops when you release your hand. In addition to being convenient, it is not necessary to touch the handle with dirty hands and it is hygienic, so it is widely used. In such an automatic water faucet, it is necessary to accurately determine the approach or separation of an object to be cleaned such as a user's hand or a cup in order to control water discharge and water stoppage. Until now, as shown in Patent Document 1, a microwave is used to detect a human body, a reflected wave of a microwave radiated from a microwave sensor is received, a power spectrum of a Doppler frequency signal is obtained, and a peak value thereof is obtained. There is known an apparatus for detecting a human body by comparing a predetermined threshold with a predetermined threshold. Moreover, as shown in Patent Document 2, an automatic faucet is also known in which a microwave sensor is applied to the spout water control of the automatic faucet and further prevents erroneous detection of only the spout water flow as a detected body. ing. In such a microwave sensor, the moving speed and acceleration of the detected object are detected to detect that the user approaches the water discharger.

Japanese Patent Laid-Open No. 9-80150 JP 2009-150190 A

In the conventional automatic faucet control using the radio wave sensor, as described above, the movement speed and acceleration of the detected object (that is, the user himself / herself, the hand to be cleaned, etc.) are detected to discharge the automatic faucet. Water stop control was performed.
When such an automatic faucet is provided in a wash basin, etc., the radio wave sensor controls the water stoppage of the automatic faucet by detecting the approach or separation of the user from the wash basin. As a case of approaching the wash basin, it is conceivable that it is not for washing hands or the like, but for approaching the wash basin for grooming using the mirror of the wash basin. Also in this case, the automatic faucet using the conventional radio wave sensor detects the approach of the user himself / herself to the washstand, that is, the user's torso etc. approaches the washstand and discharges water. In spite of the situation where water discharge is not particularly desired, water discharge is performed.
In addition, even if the object to be cleaned has been detected and water is discharged, if the hand or cup is stopped in the vicinity of the water outlet for water pooling, the water discharge control is stopped only by moving speed or acceleration, and water cannot be collected. There was a problem.

  Therefore, the present invention has been made to solve the above-described problems, and is an automatic faucet using a radio wave sensor that accurately determines the user's operation from the frequency and amplitude of the Doppler signal, and uses it. Provide an easy-to-use automatic faucet.

In order to achieve the above object, the present invention receives a reflected wave signal of a water discharge unit and a radiated radio wave, mixes a part of a transmission signal with a mixer unit, and generates a Doppler signal obtained through a filter circuit. The automatic faucet includes a sensor unit disposed near the water discharge unit, and a determination unit that determines the approach of the detected object based on the frequency and amplitude of the Doppler signal generated by the sensor unit. Based on the frequency and amplitude of the Doppler signal, it is determined whether the object to be detected is a user or an object to be cleaned that is smaller than the user. It is determined that an object to be cleaned that is smaller than the person approaches the vicinity of the water discharge portion, and the water discharge control of the water discharge portion is performed according to the determination result of the determination portion.
In the present invention configured as above, water is not discharged just by the user himself / herself approaching the vicinity of the water discharge part, and the user causes the object to be cleaned, for example, a hand or a cup, to approach the water discharge part, thereby discharging water. Therefore, it is possible to accurately determine the operation of the user and provide an automatic faucet that is convenient for the user.

In the present invention, preferably, the determination of the user's approach to the vicinity of the water discharge unit is performed by the determination unit based on whether or not the amplitude value of the Doppler signal is equal to or greater than a predetermined value, and the object to be detected is the object to be cleaned. And the approach of the object to be cleaned to the vicinity of the water discharger are determined by setting the amplitude value of the Doppler signal when the user is closest to the receiver as the first amplitude threshold, which is smaller than the first amplitude threshold. A second amplitude threshold value having a value, and whether or not a Doppler signal having an amplitude value smaller than the first amplitude threshold value and larger than the second amplitude threshold value continues for the first time threshold value or more, or from the first amplitude threshold value The speed of movement of the detected object that generates the Doppler signal is determined based on the frequency of the Doppler signal having a smaller amplitude value than the second amplitude threshold, and the speed of the detected object is obtained by time integration. The travel distance is Whether a distance threshold or more, is performed by.
In the present invention configured as described above, after approaching the vicinity of the user's own water discharge section, it can be determined that the approach of the object to be cleaned has started near the water discharge section, and the user's operation is accurately determined. In addition, it is possible to provide an automatic faucet that is convenient for the user.

In the present invention, preferably, the start of water discharge in the water discharge control is such that the determination unit further provides a third amplitude threshold value having a value larger than the first amplitude threshold value, and the object to be cleaned starts approaching the vicinity of the water discharge unit. After the determination, the amplitude value of the Doppler signal from the object to be cleaned is larger than the third amplitude threshold value, and the frequency of the Doppler signal from the object to be cleaned is equal to or lower than the first frequency threshold value.
In the present invention configured as described above, since the water discharge is started by determining the arrival of the object to be cleaned in the vicinity of the water discharge portion, the user's operation is accurately determined, and the automatic water faucet that is convenient for the user is used. Can be provided.

In the present invention, it is preferable that the discriminating unit further obtains the speed of movement of the detected object that generates the Doppler signal based on the frequency of the Doppler signal, and measures the amplitude value of the Doppler signal exceeding the third amplitude threshold value. When the moving distance between the time point when the frequency of the Doppler signal is equal to or lower than the first frequency threshold value is equal to or greater than the second distance threshold value, it is determined that the object to be cleaned has passed near the water discharge portion. Do not discharge water.
In the present invention configured as described above, for example, even when the object to be cleaned passes near the water discharge portion and reaches to the back of the washstand, this is accurately determined and water discharge is not performed. Therefore, it is possible to provide an automatic faucet that is convenient for the user.

In the present invention, it is preferable that the determination unit further includes a fourth amplitude threshold value having an amplitude value of the Doppler signal larger than the first amplitude threshold value, and has an amplitude value equal to or lower than the fourth amplitude threshold value in the water discharge. When the Doppler signal continues for the second time threshold or more, or the movement distance of the detected object that generates the Doppler signal having the amplitude value equal to or smaller than the fourth amplitude threshold obtained based on the frequency of the Doppler signal is the third distance threshold. When it becomes above, it judges that a user's washing operation was completed and stops water discharge.
In the present invention configured as described above, since the user can accurately determine the operation of retracting the hand after finishing the cleaning operation, the water discharge is not stopped even in a situation where the water is accumulated without retracting the hand. Therefore, it is possible to provide an automatic faucet that is convenient for the user.

In the present invention, it is preferable that the determination unit has an amplitude greater than or equal to a detection lower limit value that is a minimum amplitude value of a signal indicating detection of the detected object from a state where the detected object is not detected. In the case of a Doppler signal, when it is determined that the user has been detected, and then the frequency of the Doppler signal becomes equal to or lower than the second frequency threshold value indicating a predetermined speed, the user stops moving and the user is the most in the receiving unit. It is determined that the two have approached, and the maximum value of the amplitude value of the Doppler signal in this process is set as the first amplitude threshold value.
In the present invention configured as described above, after detecting the approach of the user, in order to determine the operation of the object to be cleaned based on the state where the user approaches and stops, the user's own operation and the object to be cleaned It is possible to accurately discriminate the movement from an object and provide an automatic faucet that is convenient for the user.

In the present invention, it is preferable that the discriminating unit is configured so that, even when the amplitude value of the Doppler signal is equal to or higher than a predetermined value, before the frequency of the Doppler signal becomes equal to or lower than the second frequency threshold value indicating the predetermined speed, When the amplitude value of the Doppler signal is equal to or less than the detection lower limit value that is the minimum amplitude value of the signal indicating the detection of the detection object, it is determined that the user has passed the detection range of the sensor unit.
In the present invention configured as described above, since it can be determined that the user has passed in front of the washbasin, it is possible to accurately determine the operation of the user and provide an automatic water faucet that is convenient for the user. Can do.

In the present invention, preferably, the movement of the detected body in the direction of approaching the vicinity of the water discharge section detects the amplitude of the Doppler signal generated by the predetermined detected body a plurality of times at time intervals. It is determined when the signal amplitude increases with time, and when the signal amplitude decreases with time, it is determined that the detected object is moving away from the vicinity of the water discharger.
In the present invention configured as described above, since the direction of movement of the detected object such as the user or the object to be cleaned can be determined, the operation of the user is accurately determined, and the automatic water that is convenient for the user is used. A plug can be provided.

  According to the automatic faucet of the present invention, based on the Doppler signal generated by the radio wave sensor, the user's own movement and the movement of the object to be cleaned such as the user's hand are discriminated, respectively, and the water discharge control is performed. As a result, it is possible to accurately discriminate the operation of the user and provide an automatic faucet that is convenient for the user.

It is a perspective view which shows the state which installed the automatic faucet by embodiment of this invention in the washstand. It is side surface sectional drawing which shows the state which installed the automatic faucet by embodiment of this invention in the washstand. It is a block diagram which shows the structure of the automatic water tap by embodiment of this invention. It is a wave form diagram showing an example of a waveform of a Doppler signal which a radio wave sensor of an automatic faucet by an embodiment of the present invention generated, and a threshold. It is a wave form diagram showing an example of a waveform of a Doppler signal which a radio wave sensor of an automatic faucet by an embodiment of the present invention generated, and a threshold. It is a wave form diagram showing an example of a waveform of a Doppler signal which a radio wave sensor of an automatic faucet by an embodiment of the present invention generated, and a threshold. It is a wave form diagram showing an example of a waveform of a Doppler signal which a radio wave sensor of an automatic faucet by an embodiment of the present invention generated, and a threshold. It is a wave form diagram showing an example of a waveform of a Doppler signal which a radio wave sensor of an automatic faucet by an embodiment of the present invention generated, and a threshold. It is a flowchart figure which shows the control processing of the automatic faucet based on the Doppler signal which the radio wave sensor by embodiment of this invention produced | generated. It is a flowchart figure which shows the control processing of the automatic faucet based on the Doppler signal which the radio wave sensor by embodiment of this invention produced | generated.

Next, an automatic faucet according to an embodiment of the present invention will be described with reference to the accompanying drawings.
First, the configuration of an automatic faucet according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view illustrating a state in which an automatic faucet according to an embodiment of the present invention is provided on a wash basin, and FIG. 2 schematically illustrates a state in which the automatic faucet according to an embodiment of the present invention is provided on a wash basin. It is side surface sectional drawing shown. FIG. 3 is a block diagram showing the configuration of the automatic faucet according to the embodiment of the present invention.

  As shown in FIG.1 and FIG.2, the automatic water tap 1 by embodiment of this invention is provided in the washstand. The wash basin includes a sink portion 2 and a spout 3 (water discharge portion, water discharge port) for discharging water is provided in the sink portion 2. The spout 3 is disposed so as to discharge water with respect to the sink portion 2 from obliquely upward to obliquely downward. A water supply pipe 4 is connected to the spout 3. The water supply pipe 4 is a flexible tubular member and supplies water to the spout 3. The water supply pipe 4 is provided with a water discharge valve 5. The water discharge valve 5 is an electromagnetic valve, and is configured to perform an opening / closing operation by a control signal from the control unit 10. Further, the water discharge valve 5 is a constant flow valve, and a constant flow of water is supplied toward the spout 3 through the water supply pipe 4 during the opening operation.

The control unit 10 is usually installed below the sink unit 2 at a position that is not visible when the user uses the washstand. The control unit 10 is electrically connected to the water discharge valve 5 and the radio wave sensor 20, and controls the opening and closing of the water discharge valve 5 based on a signal from the radio wave sensor 20, as will be described later. Control water stop.
The radio wave sensor 20 is installed on the back side of the wall surface at the back of the front surface of the sink part 2 and is provided below the spout 3. The radio wave sensor 20 is a microwave Doppler sensor, and the frequency used is, for example, about 10 GHz or about 24 GHz. The radio wave sensor 20 is arranged so that the detection range 100 extends obliquely upward from the back side of the sink part 2 of the washstand as viewed from the side of the washstand. It is preferable that the edge of the sink part 2 on the front side when viewed from the user of the sink part 2 has an angle that does not cover the detection range 100. This is to prevent the microwave transmitted from the radio wave sensor 20 from being irregularly reflected by the edge on the front side of the sink part 2. On the other hand, it is preferable to have a forward spread to such an extent that the approach of the user who uses the washstand can be detected.

  As illustrated in FIG. 3, the control unit 10 includes a determination unit 12 and a memory unit 13. The determination unit 12 and the memory unit 13 are configured by a microcomputer or the like. The determination unit 12 receives a Doppler signal via a filter circuit 25 in the radio wave sensor 20 described later. Information on the frequency and signal amplitude can be obtained from this signal. The discriminating unit 12 stores various information related to the signal in the memory unit 13 and uses it in the discriminating process described later. Based on the waveform of the Doppler signal, the discriminating unit 12 discriminates each condition relating to the amplitude, frequency, time, and distance of the Doppler signal, and the user himself / herself or an object to be cleaned such as a hand / cup close to the radio wave sensor 20. Control of water discharge from the spout 3, which will be described later, is executed after determining whether or not, separation or passage. This water discharge control is executed by opening / closing control of the water discharge valve 5 connected to the control unit 10. As shown in FIG. 3, the radio wave sensor 20 includes a transmitter 22, a receiver 23, a mixer 24, an antenna 21 that transmits microwaves and receives reflected waves, and a mixer 24. Is provided with a filter circuit 25 for extracting a low frequency component of the output signal. The transmission unit 22, the reception unit 23, the mixer unit 24, the antenna 21, and the filter circuit 25 are electrically connected, and the radio wave sensor 20 transmits a transmission wave (transmission signal) from the transmission unit 22 via the antenna 21. Then, the reception unit 23 receives the reflected wave (received signal) reflected by the transmitted wave hitting the user of the washstand or the object to be cleaned through the antenna 21. Then, the mixer unit 24 mixes these transmission signal and reception signal, and an output signal reflecting the Doppler effect is output to the control unit 10 as a Doppler signal.

When the object to be detected is stationary, the radio wave sensor 20 cannot detect the presence or absence of the object to be detected because the frequencies of the transmission wave (transmission signal) and the reflected wave (reception signal) are the same. However, when the object to be detected is moving, the frequency of the reflected wave changes, so that a so-called Doppler signal appears at the output of the mixer unit 24. The faster the movement of the object to be detected, the larger the frequency of the Doppler signal, and the slower the movement of the object to be detected, the smaller the frequency of the Doppler signal.
In addition, the determination unit 12 of the control unit 10 obtains the speed of movement of the detected object based on the frequency of the Doppler signal from the detected object, and performs time integration on the obtained speed to thereby detect the detected object. The travel distance can be calculated.

The radio wave sensor 20 sends information including the value of the signal amplitude to the control unit 10 regarding the signal intensity of the Doppler signal. Note that the intensity of the reflected wave signal of the microwave depends on the size of the detected object that reflects the microwave and the distance between the radio wave sensor 20 and the detected object. The signal intensity of the reflected wave increases as the size of the detected object increases, and the signal intensity of the reflected wave increases as the detected object approaches the radio wave sensor 20. In particular, the influence of the distance between the radio wave sensor 20 and the object to be detected is large, and when a microwave sensor is used, the signal intensity of the reflected wave is known to be inversely proportional to the fourth power of the distance between the sensor and the object to be detected. ing. On the other hand, since the amplitude intensity of the Doppler signal is the product of a part of the radiated radio wave having a constant amplitude intensity added to the mixer unit and the amplitude of the reflected wave signal, the amplitude intensity of the Doppler signal is the same as the amplitude intensity of the reflected wave signal. , Inversely proportional to the fourth power of the distance between the sensor and the object to be detected. As will be described later, the user himself (such as the user's upper body and torso) is larger than the hand or cup that is the object to be cleaned, but is closer to the spout 3 than the user standing in front of the sink. The approached object to be cleaned is closer to the radio wave sensor 20. Also, since the object to be cleaned is accompanied by some movement, the reflected wave reflects the Doppler effect and is closer to the spout 3 than the signal intensity of the reflected wave reflected by the user himself when approaching the washstand. Thus, the signal intensity of the reflected wave reflected by the object to be cleaned is increased. The determination unit 12 sets a detection lower limit value in advance as the minimum amplitude value of the signal indicating the detection of the detected object with respect to the value of the signal amplitude of the Doppler signal from the radio wave sensor 20, and an amplitude less than the detection lower limit value is set. The signals that are included are not identified as noise.
The present invention detects the user's own movement and the movement of the object to be cleaned based on the frequency and amplitude of the Doppler signal generated by the radio wave sensor 20 based on the configuration of the automatic faucet described above. In addition, the user uses and determines the usage purpose and usage status of the wash basin to perform water discharge control and water stop control.

Hereinafter, with reference to FIG. 4 to FIG. 8, the difference in the waveform of the Doppler signal depending on the purpose and usage of the washstand by the user, each threshold value used in the determination process described later, and the like will be described. The flow of discrimination processing based on the difference in waveform will be described with reference to the flowcharts of FIGS.
In addition, in order to express each measurement value and threshold value concisely, “A” is related to amplitude, “F” is related to frequency, and “D” is related to distance. Various codes such as “T” may be used for time.

  FIG. 4 is an example of a Doppler signal generated by the radio wave sensor 20 of the automatic faucet 1. An example of a Doppler signal relating to a series of operations until the user approaches the washstand, stops and puts his hand toward the spout 3 to wash his hands is shown. Hereinafter, in each of FIGS. 4 to 8, the horizontal direction is the time axis, and the direction is such that time flows from left to right. First, in the process in which the user approaches the washstand, the amplitude of the waveform gradually increases (the “approach (body movement)” portion in FIG. 4). This indicates that the user is approaching the radio wave sensor 20. The frequency of the Doppler signal corresponds to the speed at which the user approaches the washstand. When the speed at which the user approaches the washstand is substantially constant, the frequency of the Doppler signal is also substantially constant. Here, the maximum value of the amplitude of the Doppler signal, that is, the amplitude of the Doppler signal at the point where the user is closest to the washstand is defined as the first amplitude threshold value A1 (here, S510 is a response in a flowchart described later) And so on.) When the user approaches the washstand and stops, the amplitude of the Doppler signal decreases and the frequency also decreases. The discriminating unit 12 determines that the user is stationary from the amplitude and frequency of the Doppler signal (“stationary” portion in FIG. 4). Specifically, as will be described later, it is determined whether the amplitude A of the Doppler signal is equal to or greater than the approaching stationary reference value and the frequency is equal to or less than the second frequency threshold value F2. Thereafter, when the user puts his hand toward the spout 3 to wash his hand, the operation appears again in the Doppler signal. In other words, it has a frequency that reflects the speed of movement of the hand when it is put out from the signal of the stationary state, and reflects that the distance between the hand and the radio wave sensor 20 is reduced. Then, a Doppler signal is detected so that the amplitude gradually increases (the “hand-out (hand movement)” portion in FIG. 4). Here, the second amplitude threshold value A2 smaller than the first amplitude threshold value A1 described above is set as the threshold value of the signal amplitude in the vicinity of the hand movement.

  The amplitude value of the Doppler signal is stored in the memory unit 13 of the control unit 10, and the determination unit 12 calculates data related to the waveform of the signal based on the amplitude value data stored in the memory unit 13. Comparison with each amplitude threshold value is also executed based on the amplitude value data stored in the memory unit 13. Further, the frequency value of the Doppler signal is calculated by looking at the time variation of the acquired amplitude value. In addition, as described above, since the frequency of the Doppler signal corresponds to the speed of movement of the detected object, the speed of movement of the detected object is obtained based on the frequency of the Doppler signal, and the time for the obtained speed is calculated. The moving distance of the detected object is also calculated by performing the integration.

  Thus, the discrimination | determination part 12 of the user (namely, to-be-washed | cleaned object) when taking out the hand toward the spout 3 after approaching the washstand and the user's own movement approaching the washstand. The movement can be determined by the frequency and amplitude of the Doppler signal generated by the radio wave sensor 20. When the user puts his hand toward the spout 3, the control unit 10 performs water discharge control, and opens the water discharge valve 5 to discharge water from the spout 3. Details of the water discharge control after the hand approaches the spout 3 and the operation after the hand washing will be described later with reference to FIG. 7 and FIG. A relatively simple Doppler signal waveform or the like when the person performs another operation will be described with reference to FIGS. 5 and 6 as follows.

  FIG. 5 is an example of a Doppler signal generated by the radio wave sensor 20 of the automatic faucet 1 as in FIG. An example of a Doppler signal relating to a series of operations in which a user approaches a washstand and stops and then moves out of the front of the washstand is shown. Such a series of operations corresponds to, for example, a case where the user approaches the washstand in order not to wash hands, but to wear a mirror or the like provided on the washstand. In other words, after the user approaches the washstand, looks at the mirror and wears the clothes, he leaves the front of the washstand without washing his hands.

  In the process in which the user approaches the washstand, the amplitude of the waveform gradually increases (the “approach (body movement)” portion in FIG. 5). This indicates that the user is approaching the radio wave sensor 20. The frequency of the Doppler signal corresponds to the speed at which the user approaches the sink. Here, the amplitude of the Doppler signal at the point where the user himself (user's body) is closest to the washstand, that is, the maximum value of the amplitude of the Doppler signal in this approach process is defined as the first amplitude threshold A1. When the user comes to rest after approaching the washstand, the frequency decreases and the Doppler signal also weakens. The control unit 10 determines that the user is stationary from the frequency of the Doppler signal (“stationary” portion in FIG. 5). Specifically, as will be described later, it is determined whether or not the amplitude A of the Doppler signal is equal to or greater than the approaching stationary reference value and the frequency is equal to or less than the second frequency threshold value F2. Thereafter, unlike the example shown in FIG. 4, in the example shown in FIG. 5, the user does not put out his hand toward the spout 3 because he / she wears while looking at the mirror on the spot. Therefore, unlike the waveform shown in FIG. 4, a Doppler signal derived from the hand that has been drawn out does not occur, and a Doppler signal with a small amplitude is generated due to the light movement of the user accompanying grooming. Even if the amplitude A of such a Doppler signal is smaller than the second amplitude threshold value A2 or sometimes larger than the second amplitude threshold value A2, the time to show such amplitude is a very limited time. When the dressing is finished, the user leaves (leaves) from the front of the washbasin as it is, and the Doppler signal shows this move-out action (the “leave (body movement)” portion in FIG. 5). That is, from the amplitude of the Doppler signal at the point where the user is closest to the washstand, that is, the amplitude having a value according to the first amplitude threshold value A1, the waveform gradually appears as the amplitude gradually decreases. .

When the user moves out of the washstand, the user gradually moves away from the closest point, so the amplitude value of the signal when starting the moving operation conforms to the first amplitude threshold A1. Value, that is, an amplitude value that is substantially the same size as the first amplitude threshold A1. Depending on the user's posture and the like, it is not determined whether or not a signal having an amplitude substantially the same as the first amplitude threshold A1 is generated instead of using the same value as the first amplitude threshold A1. Is preferred. As the value according to the first amplitude threshold A1, a value of about ± 10% of the value of the first amplitude threshold A1 can be used. Since the user gradually moves away from the washbasin after starting the leaving operation, the amplitude of the signal gradually decreases. If the speed of approaching and leaving the user is about the same, the waveform at the time of approaching and the waveform at the time of leaving are substantially symmetrical with respect to amplitude and frequency.
In this way, the radio wave sensor 20 generates the user's own movement approaching the washstand, the state of grooming in front of the washstand, and then the user's own movement leaving the washstand. It can be determined by the frequency and amplitude of the Doppler signal.

  FIG. 6 is an example of a Doppler signal generated by the radio wave sensor 20 of the automatic faucet 1 as in FIGS. 4 and 5. An example of a Doppler signal relating to a series of operations in which a user approaches the washstand and moves out of the washstand as it is without standing still in front of the washstand is shown. Such an operation corresponds to, for example, a case where the user simply passes through the front surface of the washstand and the detection range 100 of the radio wave sensor 20.

  In the process of the user approaching the washstand (the “approach” portion in FIG. 6), the amplitude of the Doppler signal gradually increases, indicating that the user is approaching the radio wave sensor 20. FIG. 6 shows the approaching stationary reference value of the amplitude used by the determination unit 12 to determine the user's movement. (In order to avoid complication, although not displayed in the examples shown in FIGS. 4 and 5, the approach stationary reference value of the amplitude is also used in the examples shown in FIGS. 4 and 5. 9 and 10 will be described later with reference to the flowcharts of FIGS. 9 and 10.) When the amplitude value of the Doppler signal exceeds the approach stationary reference value, the user is sufficiently equipped with the radio wave sensor 20, that is, the automatic faucet 1. It can be determined that the basin has been approached. In the example shown in FIG. 6, unlike the examples shown in FIGS. 4 and 5, the user passes as it is without moving in front of the washstand and moves away. Therefore, the signal amplitude at the time when the user changes from the process of approaching the washstand to the process of leaving the washstand (the “removal” portion in FIG. 6) is the largest amplitude among the waveforms showing a series of operations. Will have Amax. And in the process in which a user leaves the washstand, the amplitude of the Doppler signal gradually decreases. The frequency of the Doppler signal in the process of leaving the user is almost the same as the frequency of the Doppler signal when the user approaches the washstand, and the moving speed of the user passing in front of the washstand is This means that the approach is the same when approaching the washstand and when leaving the washstand.

Specifically, in order to determine whether or not the user has moved away (removed) from the washbasin, in the process of decreasing the amplitude of the signal, the frequency F of the Doppler signal is higher than the second frequency threshold F2 described above. It is determined whether the amplitude A of the Doppler signal is larger than the amplitude Amax described above. The second frequency threshold value F2 is a frequency threshold value that is also shown in FIGS. 4 and 5 and serves as a reference for determining whether or not the detected object is stationary. The second frequency threshold value F2 is a Doppler signal that is higher than the second frequency threshold value F2. When the frequency is large, it is determined that the detected object is moving. Then, when the detected object continues to move and the amplitude of the Doppler signal becomes smaller than Amax, it is determined that the movement of the detected object, that is, the user, has shifted from approaching to the washstand. Note that the amplitude of the Doppler signal decreases as the user moves away from the washstand. When the amplitude of the Doppler signal falls below the detection lower limit value, the automatic faucet 1 determines that the user is sufficiently separated, that is, has become absent, stops the detection operation, and returns to the initial state.
Thus, the frequency and amplitude of the Doppler signal generated by the radio wave sensor 20 indicate the user's own movement approaching the washstand and the user's own movement passing through the front of the washstand and leaving the washstand as it is. Can be determined.

With reference to FIG. 4 thru | or FIG. 6, it demonstrated that a user approached a washstand and the difference of a subsequent operation | movement can be discriminate | determined by a Doppler signal. When the user extends his hand toward the spout 3 with the wash basin, the above-described Doppler signal as shown in FIG. 4 is first obtained, but there are mainly two possible operations as the subsequent operation. First, the user stands still in front of the washbasin and extends his hand toward the spout 3, but passes the spout 3 to the back to pick up the object behind the spout 3 without performing hand washing. The action of reaching out can be considered. In this case, although the hand is put out, the hand passes in front of the spout 3 and the hand stops at the back of the spout 3.
Another operation is that the user extends his hand toward the spout 3 as in normal use, receives the water discharged from the spout 3 and performs hand washing. It is a series of actions to move out of the sink. Hereinafter, with reference to FIGS. 7 and 8, the waveform of the Doppler signal and the like relating to these operations will be described.

First, with reference to FIG. 7, the waveform of the Doppler signal when the user passes the vicinity of the spout 3 and reaches the back will be described. FIG. 7 is an example of a Doppler signal generated by the radio wave sensor 20 of the automatic faucet 1.
First, in the process in which the user approaches the washstand, the waveform amplitude gradually increases (the “approach” portion in FIG. 7). This indicates that the user is approaching the radio wave sensor 20. Note that the frequency of the Doppler signal corresponds to the speed at which the user approaches the washstand, as in the process of the user approaching the washstand described with reference to FIG. Here, the amplitude of the Doppler signal at the point where the user is closest to the washstand is defined as a first amplitude threshold A1. When the user approaches the washstand and stops, the Doppler signal also weakens, and the determination unit 12 determines that the user is stationary from the amplitude and frequency of the Doppler signal (“stationary” portion in FIG. 7). Specifically, as will be described later, it is determined whether the amplitude A of the Doppler signal is equal to or greater than the approaching stationary reference value and the frequency is equal to or less than the second frequency threshold value F2. Thereafter, when the user puts his hand toward the spout 3 to wash his hand, the operation appears again in the Doppler signal. That is, the Doppler signal has a frequency that reflects the speed of movement of the hand when the hand is put out, and the distance between the hand and the radio wave sensor 20 is reduced. A Doppler signal is detected, the amplitude of which gradually increases as a result of reflection (the first part in FIG. 7 “The first part of“ passing by hand and resting before the spout ”). Here, the second amplitude threshold A2 smaller than the first amplitude threshold A1 described above is set as the signal amplitude in the vicinity of the start of hand movement.

The discriminating unit 12 of the automatic faucet 1 according to the embodiment of the present invention is in a state where the amplitude value A of the Doppler signal is greater than or equal to the second amplitude threshold A2 reflecting this hand movement and less than the first amplitude threshold A1. The time when the amplitude value A of the Doppler signal is greater than or equal to the second amplitude threshold A2 and less than the first amplitude threshold A1 continues for the first time threshold T1 or the amplitude of the Doppler signal In the state where A is greater than or equal to the second amplitude threshold A2 and less than the first amplitude threshold A1, the movement of the user's hand (object to be cleaned) starts when the hand movement distance is greater than or equal to the first distance threshold D1. It is judged that it was done. As for a specific value of D1, generally, a general value (for example, several tens of centimeters) of the moving distance of the hand from the state where the user stands in front of the washstand to the state where the user puts his hand near the spout 3 is used. It is possible to use.
Here, regarding the movement distance of the hand (object to be cleaned), as described above as the method of obtaining the movement distance of the object to be detected, the determination unit 12 sets the frequency of the Doppler signal from the user's hand (object to be cleaned). Based on this, the speed of movement of the user's hand can be obtained, and time integration is performed for the obtained speed.

  Thereafter, the third amplitude threshold value A3 larger than the first amplitude threshold value A1 is compared with the amplitude value A of the Doppler signal, the amplitude A becomes larger than the third amplitude threshold value A3, and the frequency F of the Doppler signal is set to the first value. When the frequency threshold F1 or less, it is determined that the user's hand (object to be cleaned) has reached the vicinity of the spout 3. On the other hand, the use situation shown in FIG. 7 is a case where the user presents his / her hand in order to remove the soap or the like further behind the spout 3. In this case, when passing through the vicinity of the spout 3, the signal amplitude value of the reflected wave does not change so much and the movement of the hand continues at a predetermined speed. Therefore, a signal having a frequency component corresponding to the moving speed of the hand is continued. (In FIG. 7, “passing near the spout”). When the user's hand passes near the spout 3 and continues to be pushed further into the spout 3, the distance between the user's hand and the radio wave sensor 20 is also increased, so the amplitude of the Doppler signal is also increased. It gradually becomes smaller (in FIG. 7, the part “away from the spout”). Specifically, when it is detected that the signal amplitude of the reflected wave has fallen below the third amplitude threshold value, it is determined that the user's hand has moved in the direction away from the vicinity of the spout 3. Then, when the user reaches out and reaches the target object, the extended hand stops moving. This stillness of the hand can be determined by the fact that the frequency F of the Doppler signal has fallen below the first frequency threshold value F1 (in FIG. 7, “hand rest” portion).

Here, the determination unit 12 calculates and obtains a moving distance from when the user's hand passes near the spout 3 until it reaches the object and stops. Specifically, from when it is detected that the signal amplitude A of the Doppler signal is below the third amplitude threshold A3, until it is detected that the signal frequency F of the Doppler signal is below the first frequency threshold F1. The moving distance of the user's hand is calculated, and whether or not the moving distance D, that is, the moving distance D from when the user's hand passes through the spout 3 until it stops is equal to or greater than the second distance threshold D2. Is determined. When the moving distance of the user's hand is equal to or greater than the second distance threshold D2, the determination unit 12 determines that this series of hand movements is not a hand washing operation, and does not perform the water discharge process from the spout 3. .
In this way, the user's own movement approaching the washstand, and the user who passes near the spout 3 when passing by the user after standing in front of the washstand. Can be discriminated based on the frequency and amplitude of the Doppler signal received by the radio wave sensor 20.

Next, referring to FIG. 8, the user extends his hand toward the spout 3, receives the water discharged from the spout 3, performs hand-washing, and after hand-washing is finished, retracts the hand, and then from the washstand. The waveform of the Doppler signal and the like in the case of general use of leaving will be described. Note that other threshold values and the like, which have been omitted from the description so far as to avoid complication, will be described with reference to FIG. FIG. 8 is an example of a Doppler signal generated by the radio wave sensor 20 of the automatic faucet 1.
First, in the control unit 10 of the automatic faucet 1 according to the present invention, a detection lower limit value for detecting the movement of the user or the object to be cleaned is set in advance. When the Doppler signal has an amplitude value exceeding the detection lower limit value, the control unit 10 detects the movement of the user or the object to be cleaned. Thereafter, when the user approaches the washstand (that is, the radio wave sensor 20), a Doppler signal having a frequency corresponding to the approach speed is generated, and the amplitude of the Doppler signal gradually increases (in FIG. 8, “approach”). Part). When the amplitude of the Doppler signal exceeds the amplitude of the approaching stationary reference value (the same as the approaching stationary reference value of the amplitude shown in FIG. 6), the determination unit 12 causes the user to sufficiently connect the radio wave sensor 20, that is, the washstand. It can be determined that they are approaching. Further, when the user approaches the washstand and stops in front of the washstand, the frequency of the Doppler signal decreases accordingly. Here, when the signal amplitude of the Doppler signal takes a value equal to or greater than the approach stationary reference value described above and the frequency F of the Doppler signal is equal to or less than the second frequency threshold value F2, the user approaches the washstand. Then, it is determined that the operation has been stopped (“stationary” portion in FIG. 8).

  As will be described later with reference to the flowchart, the maximum amplitude value of the measured Doppler signal is stored and updated in the memory unit 13 as Amax in the process of approaching the user's washstand. Based on the frequency of the Doppler signal described above, the value of Amax at the time when it is determined that the user has approached the washstand and stopped is set as the first amplitude threshold A1.

  Subsequently, when the user puts his / her hand toward the spout 3 to wash his / her hand, the operation again appears in the Doppler signal, similar to the waveform of the Doppler signal shown in FIG. The threshold value for determining whether or not the hand movement has started is the second amplitude threshold value A2 that is smaller than the first amplitude threshold value A1. The time during which the amplitude value A of the Doppler signal is greater than or equal to the second amplitude threshold value A2 continues for the first time threshold value T1 or greater, and the moving distance that is greater than or equal to the second amplitude threshold value A2 is the first. When the distance is equal to or greater than the one-distance threshold D1, it is determined that the hand starts moving toward the spout 3. When a hand is put out toward the spout 3, the distance from the radio wave sensor 20 is shortened, and the amplitude of the Doppler signal is also increased. As described above, since the magnitude of the amplitude of the Doppler signal greatly depends on the distance between the radio wave sensor 20 and the object to be detected, the size of the hand (object to be cleaned) placed toward the spout 3 is determined by the user himself. The amplitude of the Doppler signal increases even if it is smaller than that. Therefore, the amplitude of the Doppler signal from the start of the movement of the hand toward the spout 3 to the arrival in the vicinity of the spout 3 is the first amplitude threshold A1 related to the amplitude of the Doppler signal when the user approaches the washstand. It is discriminated based on a third amplitude threshold A3 that is larger than that. Here, if the amplitude of the Doppler signal by the user's hand is larger than the third amplitude threshold A3, it can be determined that the vicinity of the spout 3 has been reached (the “hand-out” portion in FIG. 8). . Furthermore, in order to determine that the movement of the hand (object to be cleaned) has stopped in the vicinity of the spout 3 (that is, that the hand has not been extended to remove the object behind the spout 3), It is determined that the frequency F of the Doppler signal from the object to be cleaned is equal to or lower than the first frequency threshold value F1. Thereby, it is determined that the hand (object to be cleaned) has reached the vicinity of the spout 3 and waited for water discharge.

In response to this determination result, the control unit 10 sends a control signal to the water discharge valve 5 to open the water discharge valve 5 and starts water discharge from the spout 3. When water discharge starts, the user can wash his hands by rubbing hands. When the user moves his / her hand in the vicinity of the spout 3 along with this hand washing operation, the Doppler signal is a signal having a large amplitude and a frequency corresponding to the movement of the hand during washing (“hand washing” in FIG. 8). Part).
When the hand washing is finished, the user retracts his hand from the vicinity of the spout 3. The starting point for retracting this hand is near the spout 3. The movement when the user retracts the hand that has been handwashed in the vicinity of the spout 3 also appears in the Doppler signal as a movement of the hand away from the vicinity of the spout 3. First, the fourth amplitude threshold 4 serving as a reference when starting to retract the hand has the same size as the third amplitude threshold A3. Here, since the hand moves away from the vicinity of the spout 3, the amplitude intensity of the Doppler signal gradually decreases. The time during which the amplitude value A of the Doppler signal is equal to or smaller than the fourth amplitude threshold A4 continues for the second time threshold T2 or more, or the amplitude value A of the Doppler signal is equal to or smaller than the fourth amplitude threshold. In the state, when the moving distance of the hand becomes about the third distance threshold D3, the determination unit 12 determines that the hand washing is finished and the hand is retracted (“hand retracting” portion in FIG. 8). And the control part 10 operates the solenoid valve 5, and performs water stop control.

  After the user retracts his / her hand, the user will leave (separate) from the wash basin. The threshold for amplitude used to capture this movement is a value A1 ′ according to the first amplitude threshold A1. is there. As described above, the first amplitude threshold A1 is the maximum value of the amplitude of the Doppler signal before the user approaches the washstand and puts the hand out to the spout 3, and is not the object to be cleaned but the user's own trunk. This is the amplitude of the Doppler signal derived from the reflection due to the above. Since approach and separation with respect to the radio wave sensor 20 are symmetrical operations, the first amplitude threshold value A1 can be used as a threshold value when the user separates from the washstand, but these values do not necessarily match. Is not limited. Therefore, in the present embodiment, a value according to the first amplitude threshold A1 is used as the threshold used when the user leaves the washstand. As a value according to the first amplitude threshold A1, for example, a width of about ± 10% of the first amplitude threshold A1 can be provided.

  Here, when the amplitude of the Doppler signal is about the value A1 'according to the first amplitude threshold A1, the determination unit 12 determines that the user's own body is moving. Then, the determination unit 12 stores the amplitude value A of the Doppler signal at the time when it is determined that the user's own body is moving in the memory unit 13, and the third time threshold T3 elapses from this time. Alternatively, it is determined whether or not the amplitude value A ′ of the Doppler signal is smaller than the amplitude value A described above after the user's own body has moved by the fourth distance threshold D4. Here, the amplitude value A ′ is smaller than the amplitude value A, which means that the position of the user at the time of the amplitude value A ′ is higher than the position of the user at the time of the amplitude value A. 20, that is, it is considered to be located away from the washstand. Therefore, when the amplitude value A ′ is smaller than the amplitude value A, it is determined that the user is moving in the direction of moving away from the washstand (“removed” portion in FIG. 8). Furthermore, when the user continues to move in the direction of leaving the washstand, the amplitude of the Doppler signal becomes even smaller, and eventually the amplitude of the Doppler signal becomes less than the detection lower limit value. As described above, when the amplitude of the Doppler signal becomes equal to or lower than the detection lower limit value, a series of movements of the user is completed.

  As described above with reference to FIG. 4 to FIG. 8, a characteristic appears in the amplitude and frequency of the Doppler signal generated by the radio wave sensor 20 depending on the operation of the user. In addition, it is possible to perform water discharge / water stop control of the automatic faucet 1 according to the determination result. Hereinafter, the flow of appropriately determining the Doppler signal including these cases and controlling the operation of the automatic faucet 1 will be described with reference to the flowcharts of FIGS. 9 and 10. The timing and threshold values corresponding to the flowchart will be described as waveform diagrams corresponding to each situation with reference to FIGS. 4 to 8 as appropriate.

FIGS. 9 and 10 are flowcharts showing the water discharge treatment based on the Doppler signal generated by the radio wave sensor 20 of the automatic faucet 1 according to the embodiment of the present invention. The flowchart of FIG. 9 and the flowchart of FIG. 10 are coupled by connectors 1 to 4.
First, the control unit 10 starts detecting the approach of the user using the Doppler signal while using the radio wave sensor 20 (step S501). The control unit 10 receives information on the Doppler signal from the radio wave sensor 20 and calculates an amplitude value (step S502). This calculation can be performed mainly by the determination unit 12 using the memory unit 13. Subsequently, the determination unit 12 determines whether or not the amplitude value A of the Doppler signal is greater than or equal to the detection lower limit value (step S503). When the determination unit 12 determines that the amplitude value A of the Doppler signal is below the detection lower limit value, the control unit 10 and the radio wave sensor 20 until the detection of the Doppler signal having the amplitude value A equal to or greater than the detection lower limit value. On the other hand, when the determination unit 12 determines that the amplitude value A of the Doppler signal is equal to or greater than the detection lower limit value, the determination unit 12 has detected the movement of the user (No in step S503 to step S503). The process proceeds to the previous process (from Yes in step S503 to step S504).

When the determination unit 12 of the control unit 10 determines that the movement of the user has been detected, the determination unit 12 continues to execute the frequency calculation of the Doppler signal (step S504). Then, the cumulative moving distance of the detected object (here, the user) obtained from the frequency calculation result is calculated (step S506). As described above, this moving distance is obtained by time-integrating the speed of movement of the detected object obtained from the frequency calculation. The discriminating unit 12 stores in the memory unit 13 the maximum value among the amplitude value data, the data related to the accumulated movement distance, and the amplitude value after the movement of the detection object is detected as the maximum amplitude value Amax. And store it (step S507).
Next, the determination unit 12 determines whether or not the amplitude A of the Doppler signal is equal to or greater than the approaching stationary reference value and the frequency F of the Doppler signal is equal to or less than the second frequency threshold F2 (Step S508). The determination in step S508 corresponds to determination of whether or not the user has stopped near the washstand. First, a case where the user does not stop near the washstand will be described.

(When the user does not stop near the washstand)
First, a case where the determination unit 12 determines that the amplitude A of the Doppler signal does not exceed the approaching stationary reference value or the frequency F of the Doppler signal is greater than the second frequency threshold F2 will be described (from No in step S508). Step S513). In other words, this situation indicates that the user is not sufficiently close to the washbasin or that the user is moving at high speed, and corresponds to the above-described waveform diagram of FIG. Subsequent to step S508, the determination unit 12 compares the maximum value Amax of the amplitude of the Doppler signal and the amplitude A of the Doppler signal after the determination unit 12 detects the movement of the detected object, and the value of the amplitude A is the amplitude. It is determined whether or not it is equal to or less than the maximum value Amax (step S513). Here, when the value of the amplitude A is equal to or less than Amax, the determination unit 12 determines that the user is moving away from the automatic faucet 1 as compared to the state closest to the washstand (at the time of Amax) (Step S12). From step S513, step S514). That is, the user approaches the washstand and moves so as to move away from the washstand without stopping, so that the user determines that the user has passed through the front of the washstand (step S514). After the determination unit 12 determines whether the user has passed through, the determination unit 12 determines whether or not the amplitude A of the Doppler signal is equal to or lower than the detection lower limit value (step S527). When the amplitude A of the Doppler signal is equal to or lower than the detection lower limit value (Yes in step S527), the determination unit 12 determines that the user is no longer near the washstand, that is, is absent, and the memory unit 13 performs a series of processes. Data such as the amplitude value, cumulative movement distance, and Amax of the stored Doppler signal are initialized (step S528). In the case of the waveform of the Doppler signal shown in FIG. 6, the process proceeds from such steps S501 to S508 and from steps S508 to S513, S514, S527, and S528.

  In the above-described flow, when it is determined that the value of the amplitude A of the Doppler signal is larger than the maximum amplitude value Amax in Step S513 (No in Step S513), the determination unit 12 determines that the amplitude of the Doppler signal is still Since it is large, it is determined that the user is not away from the vicinity of the washstand. Then, the process returns to step S508, and the loop process is performed until the user continues to stand still or moves away from the vicinity of the washstand (from step S513 No to step S508).

  Further, in the flow described above, after passing through determination (step S514), if it is determined in step S527 that the amplitude A of the Doppler signal is larger than the detection lower limit value (No in step S527), the user temporarily After passing through, there is a possibility of returning to the vicinity of the washbasin again, so the process returns to step S508, where the user continues or the amplitude A of the Doppler signal becomes below the detection lower limit value, and the absence determination is made. Loop processing is performed (No in step S527 to step S508). The above is the flow of processing after No is determined in step S508, that is, the processing when the user does not stop near the washstand.

(When the user stops near the washstand)
Next, a case will be described in which the determination unit 12 determines in step S508 that the amplitude A of the Doppler signal is equal to or greater than the approaching stationary reference value and the frequency F of the Doppler signal is equal to or less than the second frequency threshold value F2. In this case, the determination unit 12 determines that the user has stopped near the washstand (from Yes in step S508 to step S509). After determining the stillness, the determination unit 12 sets the value of Amax stored in the memory unit 13 as the first amplitude threshold A1 (step S510). This situation corresponds to the approaching to stationary part of the waveform diagrams of FIGS. 4, 5, 7, and 8 described above. Note that the maximum amplitude is set to “A1” in the approaching portion. This is because, after the determination unit 12 performs the stationary determination in steps S508 to S509, the value of Amax is set as the first amplitude threshold A1 in step S510. It reflects that.

(When the user does not extend his / her hand after resting near the washbasin)
Subsequently, the determination unit 12 compares the amplitude A of the Doppler signal with the second amplitude threshold A2, and the time during which the amplitude A of the Doppler signal is equal to or greater than the second amplitude threshold A2 continues for the first time threshold T1 or more. Whether or not the movement distance of the detected object calculated based on the Doppler signal is equal to or greater than the first distance threshold D1 in a state where the amplitude A of the Doppler signal is equal to or greater than the second amplitude threshold A2. Is determined (step S511). Here, when none of these conditions is satisfied, it is determined that the movement of the hand toward the spout 3 (water discharger) has not started (from No in step S511 to the connector 2). If it is determined that the movement of the hand has not been started, the determination unit 12 next determines whether or not the amplitude A of the value corresponding to the first amplitude threshold A1 has occurred for the amplitude A of the Doppler signal ( Step S523) from the connector 2 in FIG. When it is determined that the amplitude A having a value according to the first amplitude threshold A1 has not occurred (No in step S523), the process returns to step S511 again (from No in step S523 through the connector 3 to step S511 in FIG. 9). ). As described above, the loop processing is performed until Yes is determined in Step S511 or No is determined in Step S523. This situation is the situation where the user is in front of the washstand, the hand is not put out toward the spout 3 and the user does not leave the front of the washstand, that is, used in front of the washstand. 5 represents a situation where a person is dressed, and the “stationary” portion of the waveform diagram of FIG. 5 corresponds to this situation.

  From such a situation, when the amplitude A of the value corresponding to the first amplitude threshold A1 is generated for the amplitude A of the Doppler signal, the determination unit 12 determines that the movement of the user's body has occurred (Yes in step S523). To step S524). Subsequently, the determination unit 12 determines that the amplitude A of the Doppler signal immediately after the start of movement and the movement distance of the user calculated from the Doppler signal after the third time threshold T3 has elapsed after the start of movement are the fourth distance. The amplitude A ′ of the Doppler signal after moving by the threshold value is compared, and it is determined whether or not the amplitude A ′ is smaller than the amplitude A (step S525). If the amplitude A ′ is greater than or equal to the amplitude A, the loop processing in step S525 is continued until the amplitude A ′ becomes smaller than the amplitude A (No in step S525 to step S525). When the amplitude A ′ becomes smaller than the amplitude A, the determination unit 12 determines that the user is moving in the withdrawal direction (Yes from step S525 to step S526). Thereafter, the process proceeds to step S527 in FIG. 9 via the connector 4. In step S527, it is determined whether or not the amplitude A of the Doppler signal is equal to or lower than the detection lower limit value, and the subsequent processes are the same as those described above.

(When the user puts his hand after resting near the washbasin)
Whether the amplitude A of the Doppler signal is greater than or equal to the second amplitude threshold A2 and less than the first amplitude threshold A1 continues in the determination unit 12 for the first time threshold T1 or greater in Step S511, In a state where the amplitude A is greater than or equal to the second amplitude threshold A2 and less than the first amplitude threshold A1, the movement distance of the detected object calculated based on the Doppler signal is greater than or equal to the first distance threshold D1. When it is discriminated, it is determined that the movement of the hand is started (from Yes of step S511 to step S512). If the determination unit 12 determines that the movement of the hand has started, the amplitude A of the Doppler signal subsequently becomes equal to or greater than the third amplitude threshold A3 that is larger than the first amplitude threshold A1, and the frequency F of the Doppler signal Is less than or equal to the first frequency threshold F1 (step S515). Here, when the amplitude A of the Doppler signal is equal to or greater than the third amplitude threshold A3 that is larger than the first amplitude threshold A1, the user who has stopped still near the washstand has further placed his hand near the spout 3. It is indicated that the movement of the hand near the spout 3 has become slow because the frequency F of the Doppler signal is equal to or lower than the first frequency threshold value F1. That is, by satisfying these conditions, it is determined that the user's hand has reached the vicinity of the spout 3 (water discharger) (Yes from step S515 to step S516).
After the determination unit 12 determines that the user's hand has reached the vicinity of the spout 3, the control unit 10 controls the water discharge valve 5 to open the faucet (step S517). Thereby, water discharge from the spout 3 is performed, and it is possible to wash an object to be cleaned such as a hand that the user put out toward the spout 3.

  The discriminating unit 12 continues to monitor the Doppler signal even during spitting, and the time during which the amplitude A of the Doppler signal is equal to or less than the fourth amplitude threshold A4 continues for the second time threshold T2 or the Doppler signal. In a state where the amplitude A is equal to or smaller than the fourth amplitude threshold A4, it is determined whether or not the moving distance of the user's hand (object to be cleaned) is equal to or larger than the third distance threshold D3, and the amplitude A of the Doppler signal is further determined. Is continued in a state of less than the fourth amplitude threshold A4 (step S519). The time during which the amplitude A of the Doppler signal is equal to or lower than the fourth amplitude threshold A4 does not continue for the second time threshold T2 or more, and the amplitude A of the Doppler signal is equal to or lower than the fourth amplitude threshold A4. When it is determined that the moving distance of the hand (object to be cleaned) is less than the third distance threshold D3, it is determined that the hand washing is continued, and the loop processing of step S519 is continued (from No in step S519 to step S519). ). Further, the time when the amplitude A of the Doppler signal is equal to or less than the fourth amplitude threshold A4 continues for the second time threshold T2 or more, or the Doppler signal amplitude A is equal to or less than the fourth amplitude threshold A4. Even if the movement distance of the person's hand (object to be cleaned) is equal to or greater than the third distance threshold D3, if the amplitude A of the Doppler signal does not continue below the fourth amplitude threshold A4, hand washing continues in the same manner. The loop process of step S519 is continued (No from step S519 to step S519).

  On the other hand, the time when the amplitude A of the Doppler signal is equal to or smaller than the fourth amplitude threshold A4 continues for the second time threshold T2 or more, or the Doppler signal amplitude A is equal to or smaller than the fourth amplitude threshold A4. When the movement distance of the person's hand (object to be cleaned) is equal to or greater than the third distance threshold D3 and the amplitude A of the Doppler signal continues below the fourth amplitude threshold A4, the determination unit 12 has finished hand washing (SYes from step S521 to step S521). Then, the control unit 10 controls the water discharge valve 5 to close the faucet (step S522). After the faucet is closed, the process proceeds to the above-described step S523 for determining whether or not the user leaves the vicinity of the washstand, and the subsequent processes are performed as described above.

(When the user stops near the washbasin and then puts out his hand and passes near the spout)
In step S515, when the amplitude A of the Doppler signal is equal to or greater than the third amplitude threshold A3 that is greater than the first amplitude threshold A1, and the frequency F of the Doppler signal is not equal to or less than the first frequency threshold F1 (step S515). No), there is a possibility that the user's hand is passing the vicinity of the spout 3 and trying to take the object behind. In this case, the determination unit 12 next determines the position between the position when the amplitude A of the Doppler signal becomes the third amplitude threshold A3 and the position when the frequency F of the Doppler signal becomes equal to or less than the first frequency threshold F1. It is determined whether or not the distance is greater than or equal to the second distance threshold D2 (from No in step S515 to step S518). (As described above, the moving distance of the object to be detected is obtained by time integration with respect to the speed obtained from the frequency of the Doppler signal.) The position when the amplitude A of the Doppler signal becomes the third amplitude threshold A3. And when the distance between the position at which the frequency F of the Doppler signal becomes equal to or lower than the first frequency threshold value F1 is less than the second distance threshold value D2, the process returns to step S515 again, and steps S515 and S518 are performed. Loop processing is performed. The distance between the position when the amplitude A of the Doppler signal becomes the third amplitude threshold A3 and the position when the frequency F of the Doppler signal becomes equal to or less than the first frequency threshold F1 is greater than or equal to the second distance threshold D2. If it is determined that there is an object, it is determined that the movement of the detected object is not an operation related to hand washing, and the first time threshold value T1 and the first distance threshold value D1 are initialized (from Yes in step S518 to step S520). Thereafter, the processing proceeds to step S511 of FIG. 9 via the connector 3, and the subsequent processing proceeds as described above.

  Thus, a series of processing is performed by the control part 10, and it is possible to perform the spout water control of the automatic water tap 1 according to each use condition of the user. In addition, although the magnitude relationship between threshold values is prescribed | regulated about the various threshold value mentioned above, since the specific value of these threshold values also depends on the system configuration | structure of the automatic faucet 1, the arrangement | positioning of the electromagnetic wave sensor 20, etc. In advance, it is preferable to perform a test using subjects having various physiques such as adults and children, and optimize a specific value of the threshold.

  In addition, in a series of processes, in addition to determination using a predetermined threshold value, the amplitude of a Doppler signal generated by a predetermined object to be detected is detected a plurality of times at predetermined time intervals and the relative change is observed. It is also possible to obtain information on the movement of the detected object. As for the amplitude of the Doppler signal, when the signal amplitude increases with time, it can be determined that the detected object is moving in a direction approaching the vicinity of the spout 3. Further, when the signal amplitude decreases with time, it can be determined that the detected object is moving away from the vicinity of the spout 3, that is, moving in the direction of retreat.

Next, the effect of the automatic faucet according to the above-described embodiment of the present invention will be described.
According to the automatic faucet according to the above-described embodiment of the present invention, it is possible to accurately discriminate between the user's own movement and the movement of an object to be cleaned such as the user's hand. And even if a user does not perform hand washing simply by approaching the washstand provided with the automatic faucet of the present invention, this can be accurately determined. Since it is possible to perform water discharge control according to the determined use situation, it is possible to provide an automatic faucet that is convenient for the user.

DESCRIPTION OF SYMBOLS 1 Automatic faucet 2 Sink part 3 Spout 4 Water supply pipe 5 Water discharge valve 10 Control part 12 Discriminating part 13 Memory part 20 Radio wave sensor 21 Antenna 22 Transmitting part 23 Receiving part 24 Mixer part 25 Filter circuit 100 Detection range

Claims (8)

A water discharge part,
Receiving a reflected wave signal of the radiated radio wave, mixing a part of the transmission signal with a mixer unit, and generating a Doppler signal obtained through a filter circuit;
An automatic faucet comprising a discriminating unit for discriminating the approach of the detected object based on the frequency and amplitude of the Doppler signal generated by the sensor unit,
The determination unit determines whether the object to be detected is a user or an object to be cleaned smaller than the user based on the frequency and amplitude of the Doppler signal, and further, the user's The approach to the vicinity of the water discharge part and the approach to the vicinity of the water discharge part of an object to be cleaned that is smaller than the user are determined,
An automatic faucet that performs water discharge control of the water discharger in accordance with the determination result of the determination unit. The determination of the approach of the user to the vicinity of the water discharge unit is performed by the determination unit based on whether or not the amplitude value of the Doppler signal is equal to or greater than a predetermined value.
The determination that the object to be detected is the object to be cleaned and the determination of the approach of the object to be cleaned to the vicinity of the water discharge unit are the amplitude values of the Doppler signal at the time when the user is closest to the receiving unit. Is a first amplitude threshold, a second amplitude threshold having a value smaller than the first amplitude threshold is provided, and a Doppler signal having an amplitude value smaller than the first amplitude threshold and larger than the second amplitude threshold is Detected whether the Doppler signal is generated based on whether the Doppler signal has continued for a first time threshold or more, or based on the frequency of the Doppler signal having an amplitude value smaller than the first amplitude threshold value and larger than the second amplitude threshold value It is performed by determining whether the moving distance of the detected object obtained by calculating the speed of movement of the body and integrating the speed with respect to time is equal to or greater than a first distance threshold.
The automatic faucet according to claim 1. The start of water discharge in the water discharge control,
The determination unit further provides a third amplitude threshold value having a value larger than the first amplitude threshold value, and after determining that the object to be cleaned has started to approach the water discharge unit,
An amplitude value of a Doppler signal from the object to be cleaned is larger than the third amplitude threshold value;
Performed when the frequency of the Doppler signal from the object to be cleaned is equal to or lower than a first frequency threshold,
The automatic faucet according to claim 2.   The determination unit further obtains the speed of movement of the detected object that generates the Doppler signal based on the frequency of the Doppler signal, and measures the amplitude value of the Doppler signal exceeding the third amplitude threshold value. When the moving distance from the time when the frequency of the Doppler signal is equal to or lower than the first frequency threshold is equal to or greater than the second distance threshold, it is determined that the object to be cleaned has passed near the water discharge portion. The automatic faucet according to claim 3, wherein water is not discharged.   The determination unit further includes a fourth amplitude threshold value having an amplitude value of the Doppler signal larger than the first amplitude threshold value, and the Doppler signal having an amplitude value equal to or smaller than the fourth amplitude threshold value in water discharge. Is the second distance threshold or the movement distance of the detected object that generates a Doppler signal having an amplitude value less than or equal to the fourth amplitude threshold obtained based on the frequency of the Doppler signal is a third distance threshold. The automatic water faucet according to claim 3, wherein when it becomes the above, it is determined that the user's cleaning operation is finished, and water discharge is stopped.   The first amplitude threshold value is equal to or greater than a detection lower limit value where the amplitude value of the Doppler signal is a minimum amplitude value of a signal indicating detection of the detected object from a state where the determination unit does not detect the detected object. When the Doppler signal has an amplitude of λ, it is determined that the user has been detected, and when the frequency of the Doppler signal becomes equal to or lower than the second frequency threshold value indicating the predetermined speed, the user stops moving. 6. The method according to claim 2, wherein it is determined that the user is closest to the receiving unit, and a maximum value of an amplitude value of a Doppler signal in this process is set as the first amplitude threshold value. Automatic faucet.   Even if the amplitude value of the Doppler signal is equal to or higher than a predetermined value, the determination unit is configured to detect the Doppler signal before the frequency of the Doppler signal becomes equal to or lower than a second frequency threshold value indicating a predetermined speed. 7. The device according to claim 2, wherein when the amplitude value is equal to or lower than a detection lower limit value that is a minimum amplitude value of a signal indicating detection of the detection target, it is determined that the user has passed the detection range of the sensor unit. The automatic faucet according to claim 1. The movement of the detected body in a direction approaching the vicinity of the water discharge section is detected by the determination section a plurality of times at predetermined time intervals with respect to the amplitude of the Doppler signal generated by the predetermined detected body. Determined when the signal amplitude increases,
The automatic water faucet according to any one of claims 1 to 7, wherein when the signal amplitude decreases with time, the object to be detected is determined to be moving in a direction away from the vicinity of the water discharger.

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