JP2019178495A - Water discharge device - Google Patents

Abstract

To provide a water discharge device with a simple configuration capable of suppressing influence of light other than detection light.SOLUTION: A water discharge device comprises: a water discharge unit; a water supply passage for guiding water from a water supply source to the water discharge unit; an on-off valve for opening/closing the water supply passage; a photoelectric sensor that projects detection light, receives reflection light of the detection light, and outputs a reception signal corresponding to a light reception amount of the reflection light; and a control unit that on the basis of the reception signal, detects the existence of an object and controls opening/closing of the on-off valve depending on a result of the object detection. The photoelectric sensor includes: a light projection element for projecting the detection light; a light receiving element for receiving the reflection light; a first polarization member for allowing light having first polarization included in the detection light to transmit; and a second polarization member that cuts off light having second polarization generated via mirror reflection and allows light having third polarization differing from the second polarization to transmit, the light having the second polarization and the light having the third polarization included in the reflection light. The light receiving element has a wavelength band including a wavelength outside a wavelength band of the detection light; the second polarization member has a wavelength band including a wavelength outside the wavelength band of the light receiving element.SELECTED DRAWING: Figure 1

Description

  Aspects of the present invention generally relate to a water discharge device.

  There is known a water discharge device including a photoelectric sensor composed of a light projecting element and a light receiving element. In the photoelectric sensor of such a water discharging apparatus, it is known to arrange a polarizing member in front of the light projecting element and the light receiving element (for example, Patent Document 1).

  The detection light projected from the light projecting element is converted into predetermined polarized light by the polarizing member, and is irradiated onto the object. Of the light reflected by the object, polarized light different from that at the time of projection passes through the polarizing member and enters the light receiving element. Thereby, the reflected light of the hand that has been diffusely reflected passes through the polarizing member and is received by the light receiving element, and the light that is specularly reflected by metal or the like is blocked by the polarizing member. Therefore, an object can be reliably detected by the photoelectric sensor.

  The light projecting element projects detection light of a predetermined wavelength band. If the wavelength band of the light that can be received by the light receiving element is narrower than the wavelength band of the detection light projected from the light projecting element, a part of the detection light emitted from the light projecting element cannot be received, and the detection accuracy is improved. There was a risk of lowering. For this reason, it is desirable that the wavelength band of light received by the light receiving element is set wider than the wavelength band of light projected by the light projecting element.

  However, if the wavelength band of light received by the light receiving element is made wider than the wavelength band of light projected by the light projecting element, the light receiving element also receives light other than the detection light of the light projecting element. The light other than the detection light of the light projecting element is ambient light such as illumination light or sunlight. Further, the wavelength band of the polarized light of the polarizing member on the light receiving element side is set according to the wavelength band of the light projecting element. For this reason, light outside the wavelength band of the detection light enters the light receiving element without being polarized by the polarizing member on the light receiving element side. Therefore, light other than the detection light becomes noise and causes a malfunction of the water discharge device.

  As a countermeasure, it may be possible to suppress the influence of light other than the detection light by adding a new member, circuit, or control. However, if such a new configuration is added, there is a risk that the size and cost of the water discharge device will increase, or the reaction rate will decrease. For this reason, in a water discharging apparatus, it is desired to be able to suppress the influence of light other than detection light with a simple configuration.

JP 2003-96850 A

  This invention is made | formed based on recognition of this subject, and it aims at providing the water discharging apparatus which can suppress the influence of lights other than detection light with a simple structure.

  The first invention comprises a water discharge section having a water discharge port for discharging water, a water supply channel for guiding water from a water supply source to the water discharge port, an on-off valve that opens and closes the water supply channel, and a detection light. A photoelectric sensor that receives reflected light of the detection light and outputs a reception signal corresponding to the received light amount of the reflected light, detects the presence or absence of an object based on the reception signal, and according to the detection result of the object A control unit that controls opening and closing of the on-off valve, and the photoelectric sensor is provided in front of the light projecting element, a light projecting element that projects the detection light, a light receiving element that receives the reflected light, and A first polarizing member that transmits the first polarized light included in the detection light and blocks the polarized light different from the first polarized light, and is provided in front of the light receiving element and is included in the reflected light. Of the light, the second polarized light is formed by specular reflection of the first polarized light. And a second polarizing member that transmits light of a third polarization different from the second polarization, and a wavelength band in which the light receiving element can receive light is other than a wavelength band of the detection light of the light projecting element The wavelength band in which the second polarizing member can block the second polarized light also has a wavelength other than the wavelength band of the light receiving element. .

  According to this water discharge device, since the wavelength band in which the second polarizing member can block the second polarized light also has a wavelength other than the wavelength band of the light receiving element, the wavelength band in which the light receiving element can receive light is projected. Even when the optical device has a wavelength other than the wavelength band of the detection light, the same component as the second polarization of the light other than the detection light can be blocked by the second polarizing member. Thereby, the incident amount of light other than the detection light incident on the light receiving element can also be reduced. Without adding a new member, circuit, control or the like, it is possible to suppress malfunction of the water discharger due to light other than the detection light. Therefore, it is possible to provide a water discharger that can suppress the influence of light other than detection light with a simple configuration.

  A second invention is the water discharge device according to the first invention, wherein the first polarized light and the second polarized light are linearly polarized light that vibrates in a direction parallel to a horizontal plane.

  For example, when light is incident on water or glass at an angle called Brewster angle, a component (so-called S wave) that vibrates in a direction parallel to the interface included in the light is reflected relatively strongly at the interface. On the other hand, the component (so-called P wave) that vibrates in the direction perpendicular to the interface included in the light is suppressed from reflection at the interface and is incident on water or glass. Therefore, in this water discharging apparatus, the first polarized light and the second polarized light are linearly polarized light that vibrates in a direction parallel to the horizontal plane. That is, light that vibrates in a direction parallel to the horizontal plane can be blocked by the second polarizing member. Thereby, it can suppress more reliably that the ambient light etc. which reflected on the water surface or glass etc. inject into a light receiving element. Therefore, malfunction of the water discharging device due to light other than the detection light can be more reliably suppressed.

  A third invention is the water discharge device according to the first or second invention, wherein the second polarizing member is a metal wire grid polarizing plate.

  According to this water discharging apparatus, it is possible to relatively easily manufacture the second polarizing member whose wavelength band capable of blocking the second polarized light is wider than the wavelength band of the light receiving element. Further, since metal is difficult to transmit ultraviolet rays, it is possible to suppress deterioration of internal resin parts and the like. More specifically, when the resin constituting the light projecting element and the light receiving element is deteriorated by ultraviolet rays, the detection accuracy is deteriorated. However, the presence of a metal in the front can reduce the incident light amount of ultraviolet rays. Further, by exhibiting polarization performance even in the wavelength region of ultraviolet rays, it is possible to further block light and further reduce the amount of incident light.

  ADVANTAGE OF THE INVENTION According to the aspect of this invention, the water discharging apparatus which can suppress the influence of light other than detection light with a simple structure is provided.

It is explanatory drawing showing the water faucet device concerning an embodiment. FIG. 2A and FIG. 2B are block diagrams showing a part of the faucet device according to the embodiment. Fig.3 (a) and FIG.3 (b) are block diagrams showing a part of faucet device concerning an embodiment. It is a flowchart showing operation | movement of the water faucet apparatus concerning embodiment.

Hereinafter, embodiments will be described with reference to the drawings. In addition, in each drawing, the same code | symbol is attached | subjected to the same component and detailed description is abbreviate | omitted suitably.
Drawing 1 is an explanatory view showing the faucet device concerning an embodiment.
As shown in FIG. 1, the faucet device 10 (water discharge device) detects a target object (human body, object, etc.) and performs automatic water discharge, and a wash basin 11 provided in a wash basin. Water is discharged against the water.

  The basin 11 is provided on the lower surface of the basin counter 12. A water faucet 13 (a water discharge portion) constituting a spout for discharging water to the bowl surface 11 a of the basin 11 is provided on the wash counter 12. The faucet 13 has a water discharge port 13 a for discharging water, and is provided so that water discharged from the water discharge port 13 a is discharged into the bowl surface 11 a of the basin 11.

  The water discharged from the water spout 13 a by the faucet 13 is supplied by the water supply channel 14. The water supply channel 14 guides water supplied from a water supply source such as a water pipe to the water discharge port 13a. A drainage channel 15 is connected to the basin 11. The drainage channel 15 discharges the water discharged from the water outlet 13a into the bowl surface 11a of the basin 11.

  The faucet device 10 includes an electromagnetic valve 16 (open / close valve), a photoelectric sensor 18, and a control unit 20. The photoelectric sensor 18 is separated from the control unit 20. The photoelectric sensor 18 is accommodated in the faucet 13, for example. The solenoid valve 16 and the control unit 20 are accommodated, for example, below the washstand. The solenoid valve 16 and the control unit 20 are accommodated in, for example, a cabinet (not shown) provided below the wash counter 12.

  The photoelectric sensor 18 and the control unit 20 are connected by a connection cable 17. For example, the control unit 20 supplies a power supply voltage to the photoelectric sensor 18 via the connection cable 17 and controls the photoelectric sensor 18 via the connection cable 17.

  The electromagnetic valve 16 is provided in the water supply channel 14 and opens and closes the water supply channel 14. When the electromagnetic valve 16 is opened, the water supplied from the water supply passage 14 is discharged from the water outlet 13a. When the electromagnetic valve 16 is closed, the water supplied from the water supply passage 14 is not discharged from the water outlet 13a. It becomes a water state.

  The electromagnetic valve 16 is connected to the control unit 20, and the control unit 20 drives the electromagnetic valve 16 to control the opening / closing operation. The electromagnetic valve 16 is electrically controlled in accordance with a control signal from the control unit 20 to open and close the water supply channel 14. Thus, the electromagnetic valve 16 functions as a water supply valve that opens and closes the water supply path 14 of water discharged from the water outlet 13a.

  The solenoid valve 16 is a self-holding solenoid valve (latched solenoid valve) called a so-called latching solenoid valve, and operates from a closed state to an open state (opening operation) by energizing the solenoid coil in one direction. After that, even if the energization to the solenoid coil is interrupted, the open state is maintained, the energization in the other direction to the solenoid coil operates from the open state to the closed state (closing operation), and then the energization to the solenoid coil is interrupted Even if it is closed. The opening and closing of the water supply path 14 is not limited to the electromagnetic valve 16, and may be performed by another open / close valve mechanism that can open and close the water supply path 14 according to the control of the control unit 20.

  The photoelectric sensor 18 detects an object (such as a hand) that approaches the spout 13a. The water discharge destination of the water discharge port 13 a becomes a detection region of the photoelectric sensor 18. The photoelectric sensor 18 projects detection light, receives reflected light of the detection light, and outputs a reception signal corresponding to the amount of received reflected light. Thereby, the position and movement of the object are detected.

  The photoelectric sensor 18 is an optical sensor using infrared detection light, for example. The detection light projected from the photoelectric sensor 18 may be, for example, visible light. Hereinafter, the detection light will be described as infrared light. The “infrared light” is light having a wavelength of 0.7 μm or more and 1000 μm or less, for example. For example, the photoelectric sensor 18 projects near-infrared detection light of 0.7 μm or more and 2.5 μm or less.

  The photoelectric sensor 18 is provided inside the faucet 13 near the water outlet 13a, and is arranged so as to project detection light toward the user side (left side in FIG. 1) of the washstand. Thereby, the photoelectric sensor 18 can detect that the human body has approached the spout 13a, that a hand has been pushed out from the human body approaching the spout 13a toward the spout 13a, and the like.

  The photoelectric sensor 18 outputs a received signal corresponding to the amount of reflected light received (detection result of the object) to the control unit 20 via the connection cable 17. The control unit 20 detects the presence / absence of an object based on the received signal output from the photoelectric sensor 18. For example, the control unit 20 detects the position and movement of the object based on the received signal. And the control part 20 controls the opening / closing operation | movement of the solenoid valve 16 based on this detection result. The control unit 20 outputs a control signal to the photoelectric sensor 18 to control the sensing operation of the photoelectric sensor 18.

  As described above, the faucet device 10 according to the present embodiment includes the faucet 13, the water supply channel 14, the electromagnetic valve 16, the photoelectric sensor 18, and the control unit 20, and is based on the reception signal of the photoelectric sensor 18. Thus, the control unit 20 controls the opening / closing operation of the electromagnetic valve 16. Thereby, the water discharge according to the detection result (movement of the user of a washstand, etc.) of the target object which approaches the water discharge opening 13a is performed. The control unit 20 performs water discharge according to the detection of the target object and stops water discharge according to the non-detection of the target object. That is, in the water faucet device 10, water is automatically discharged while the user puts out a hand or the like near the water outlet 13a.

  The photoelectric sensor 18 does not always operate, but the control unit 20 controls so as to operate at a timing that requires sensing. Thereby, the power consumption of the photoelectric sensor 18 can be reduced. For example, the control unit 20 reduces the frequency of the sensing operation of the photoelectric sensor 18 to the extent that the user does not feel inconvenient. Thereby, the power consumption of the faucet device 10 as a whole can be reduced.

Drawing 2 (a) and Drawing 2 (b) are block diagrams showing a part of faucet device concerning an embodiment.
As illustrated in FIGS. 2A and 2B, the photoelectric sensor 18 includes a light projecting unit 30 and a light receiving unit 40. The light projecting unit 30 projects detection light toward the detection area of the object. The light receiving unit 40 receives the reflected light of the detection light and outputs a reception signal corresponding to the amount of received reflected light to the control unit 20.

  2A shows the case where the detection light projected from the photoelectric sensor 18 is reflected by the diffuse reflector 2a, and FIG. 2B shows the case where the detection light transmitted from the photoelectric sensor 18 is specularly reflected. The case where it reflects with the thing 2b is represented. The diffuse reflector 2a is, for example, a ceramic basin 11. In addition, objects such as human hands are also included in the diffuse reflector 2a. The specular reflector 2b is, for example, a stainless steel basin 11. Moreover, the faucet device 10 may be used for a system kitchen. In this case, the diffuse reflector 2a is a tiled kitchen sink or the like, and the specular reflector 2b is a stainless steel kitchen sink or the like.

  The light projecting unit 30 includes a light projecting element 32 and a first polarizing member 34. The light projecting element 32 projects detection light. For example, the light projecting element 32 projects non-polarized detection light (natural light). For example, the light projecting element 32 projects non-polarized infrared light. For the light projecting element 32, for example, a light emitting element such as an LED (Light Emitting Diode) is used. The light projecting unit 30 is electrically connected to the control unit 20 and switches between the detection light projection from the light projecting element 32 and the stop of the detection light projection based on the control of the control unit 20.

  The first polarizing member 34 is provided in front of the light projecting element 32 on the optical axis of the light projecting element 32. The non-polarized detection light projected from the light projecting element 32 enters the first polarizing member 34. In other words, the light projecting element 32 projects non-polarized detection light toward the first polarizing member 34. The first polarizing member 34 transmits the first polarized light included in the non-polarized detection light projected from the light projecting element 32 and blocks the polarized light different from the first polarized light.

  The non-polarized detection light projected from the light projecting element 32 has a first polarization component and a polarization component different from the first polarization. For example, the light projecting element 32 projects detection light obliquely downward toward the front (see FIG. 1). In other words, the optical axis of the light projecting element 32 (the direction in which the detection light is projected) is inclined with respect to the horizontal plane. In this case, the first polarized light is, for example, linearly polarized light that vibrates in a direction parallel to the horizontal plane. In this case, the polarized light different from the first polarized light is, for example, linearly polarized light that oscillates in a direction perpendicular to the first polarized light.

  The linearly polarized light that vibrates in a direction parallel to the horizontal plane may not be strictly parallel to the horizontal plane. In the specification of the present application, for example, a state where the polarization plane is inclined by about ± 5 ° with respect to the horizontal plane is also included in the linearly polarized light that vibrates in a direction parallel to the horizontal plane. Similarly, in the present specification, for example, a state in which the polarization plane is inclined by about ± 5 ° with respect to the vertical plane is included in the linearly polarized light that vibrates in the direction perpendicular to the horizontal plane.

  The optical axis of the light projecting element 32 is not necessarily inclined with respect to the horizontal plane. The optical axis of the light projecting element 32 may be orthogonal to the horizontal plane, for example. In other words, the light projecting element 32 may project the detection light toward directly below. In this case, in the state where the optical axis of the light projecting element 32 is orthogonal to the horizontal plane, when the direction in which the faucet 13 faces is the front side, the first polarized light is, for example, linearly polarized light that vibrates in the left-right direction when viewed from the front side. . The polarized light different from the first polarized light is, for example, linearly polarized light that vibrates in the vertical direction when viewed from the front side. In this case, the first polarized component of ambient light incident from the front side of the faucet 13 is blocked.

  The faucet 13 is generally disposed on the rear side of the bowl surface 11a and is provided with the bowl surface 11a side facing. Thereby, it becomes possible to discharge water toward the bowl surface 11a. Thus, the water tap 13 is provided in a predetermined direction. In the state where the optical axis of the light projecting element 32 is orthogonal to the horizontal plane, when the direction facing the faucet 13 is the front side, the first polarized light is, for example, linearly polarized light that vibrates in the left-right direction when viewed from the front side. The polarized light different from the first polarized light is, for example, linearly polarized light that vibrates in the vertical direction when viewed from the front side.

  The first polarized light is not limited to the above, and may be linearly polarized light in any direction. The polarized light different from the first polarized light is not limited to the linearly polarized light in the direction orthogonal to the first polarized light, and may be linearly polarized light having an arbitrary polarization direction different from the polarization direction of the first polarized light. Hereinafter, linearly polarized light (so-called S wave) that vibrates the first polarized light in a direction parallel to the horizontal plane, and linearly polarized light (so-called P wave) that vibrates the polarized light different from the first polarized light in a direction perpendicular to the horizontal plane. Give an explanation. The first polarized light is not limited to linearly polarized light, and the same embodiment is possible with circularly polarized light or elliptically polarized light. The polarized light different from the first polarized light is not limited to linearly polarized light, and may be polarized light in any direction different from the first polarized light.

  For example, the first polarizing member 34 transmits the S wave component included in the non-polarized detection light projected from the light projecting element 32 and is included in the non-polarized detection light projected from the light projecting element 32. Blocks P wave components. Accordingly, the first polarizing member 34 converts the non-polarized detection light into S-wave detection light. Thus, the light projecting unit 30 projects the S-wave detection light transmitted through the first polarizing member 34 onto the detection region.

  In the present specification, “blocking” includes not only a state where light is not completely transmitted but also a state where light is slightly transmitted. The “blocking” is, for example, a state where the light transmittance is 10% or less. “Transmission” is, for example, a state where the light transmittance is 80% or more.

  The light receiving unit 40 includes a light receiving element 42 and a second polarizing member 44. The light receiving element 42 receives the reflected light. The second polarizing member 44 is disposed in front of the light receiving element 42 on the optical axis of the light receiving element 42. The second polarizing member 44 blocks the second polarized light formed by specularly reflecting the first polarized light out of the light included in the reflected light, and outputs the third polarized light different from the second polarized light. Make it transparent.

  When the first polarized light is an S wave, the second polarized light formed by specular reflection is also an S wave. The third polarization is, for example, a P wave. Accordingly, in this example, the second polarizing member 44 blocks the S wave component included in the reflected light and transmits the P wave component included in the reflected light. The second polarizing member 44 blocks the S wave component by, for example, at least one of reflection and absorption.

  The light receiving element 42 receives the reflected light of the P wave that has passed through the second polarizing member 44. For example, the light receiving element 42 photoelectrically converts the received P-wave reflected light to output an electrical signal corresponding to the amount of received P-wave reflected light. For the light receiving element 42, for example, a phototransistor or a photodiode having sensitivity to infrared light is used.

  The light receiving unit 40 outputs a reception signal corresponding to the amount of light received by the light receiving element 42 to the control unit 20. For example, the light receiving unit 40 outputs a reception signal corresponding to the electric signal output from the light receiving element 42 to the control unit 20.

  The wavelength band in which the light receiving element 42 can receive light has a wavelength other than the wavelength band of the detection light of the light projecting element 32. The wavelength band in which the light receiving element 42 can receive light is, for example, wider than the wavelength band of the detection light of the light projecting element 32. The wavelength band that can be received by the light receiving element 42 is not limited to the wide state on both the short wavelength side and the long wavelength side with respect to the wavelength band of the detection light of the light projecting element 32, but is wide only on the short wavelength side, Alternatively, it may be wide only on the long wavelength side. That is, the wavelength band in which the light receiving element 42 can receive light overlaps at least a part of the wavelength band of the detection light of the light projecting element 32. It is more preferable that the wavelength band that can be received by the light receiving element 42 overlaps the entire wavelength band of the detection light of the light projecting element 32.

  The wavelength band in which the second polarizing member 44 can block the second polarized light has a wavelength other than the wavelength band in which the light receiving element 42 can receive light. The wavelength band in which the second polarizing member 44 can block the second polarized light is wider than the wavelength band in which the light receiving element 42 can receive light, for example. The wavelength band in which the second polarizing member 44 can block the second polarized light is not limited to a wide state on both the short wavelength side and the long wavelength side with respect to the wavelength band that can be received by the light receiving element 42, and the short wavelength side It may be a wide state only, or a wide state only on the long wavelength side. That is, the wavelength band in which the second polarizing member 44 can block the second polarized light overlaps at least a part of the wavelength band in which the light receiving element 42 can receive light. More preferably, the wavelength band in which the second polarizing member 44 can block the second polarized light overlaps the entire wavelength band in which the light receiving element 42 can receive light.

  The wavelength band of the detection light of the light projecting element 32 is, for example, not less than 800 nm and not more than 1200 nm. Here, the wavelength band of the detection light of the light projecting element 32 is, for example, a frequency band of 1% or more in the relative energy intensity of each wavelength when the wavelength having the maximum energy intensity is 100%.

  The wavelength band in which the light receiving element 42 can receive light is, for example, not less than 650 nm and not more than 1300 nm. Thus, a part of the wavelength band in which the light receiving element 42 can receive light enters the visible light area when the wavelength band of the detection light of the light projecting element 32 is set to the near infrared range. Here, the wavelength band in which the light receiving element 42 can receive light is, for example, a frequency band of 1% or more in the relative light receiving sensitivity of each wavelength when the wavelength having the maximum light receiving sensitivity is 100%.

  The wavelength band in which the second polarizing member 44 can block the second polarized light is, for example, not less than 400 nm and not more than 1500 nm. The wavelength band in which the second polarizing member 44 can block the second polarized light is, for example, an arbitrary wavelength band that is wider than the wavelength band in which the light receiving element 42 can receive light and overlaps the entire wavelength band in which the light receiving element 42 can receive light. It's okay. Here, the wavelength band in which the second polarizing member 44 can block the second polarized light is, for example, a wavelength band in which the extinction ratio (ratio of the transmittance of the third polarized light to the transmittance of the second polarized light) is 10 or more. . In other words, the transmittance of the third polarization is a wavelength band that is 10 times or more that of the second polarization.

  The first polarizing member 34 and the second polarizing member 44 are, for example, metal wire grid polarizing plates. However, the 1st polarizing member 34 and the 2nd polarizing member 44 are not restricted to a wire grid polarizing plate, The arbitrary members which have the above characteristics may be sufficient. For example, a wire grid polarizing plate may be used for the second polarizing member 44 and another type of polarizing plate may be used for the first polarizing member 34. The second polarizing member 44 may be configured separately from the first polarizing member 34 or may be configured integrally with the first polarizing member 34 via a common base material or the like.

  In diffuse reflection, light polarized in various directions is mixed and becomes non-polarized light. For this reason, as shown in FIG. 2A, when the detection light is reflected by the diffuse reflector 2a, the reflected light includes a P wave component and an S wave component. Therefore, when the detection light is reflected by the diffuse reflector 2 a, the P wave component included in the reflected light passes through the second polarizing member 44 and enters the light receiving element 42. This makes it possible to detect an object such as a human hand.

  The control unit 20 obtains the amount of light received by the light receiving element 42 based on the electrical signal from the light receiving element 42, and detects that there is an object when the amount of light received by the light receiving element 42 exceeds a predetermined threshold.

  In addition, as illustrated in FIG. 1, the distance L1 until the detection light is reflected by the object is shorter than the distance L2 until the detection light is reflected by the washbasin 11. Therefore, for example, when the light receiving element 42 receives the P wave component of the reflected light diffusely reflected by the ceramic washbasin 11 or the like, the amount of received light is smaller than that of the object. For this reason, by appropriately setting the threshold of the amount of received light, it is possible to detect only the target object and suppress erroneous water discharge when the detection light is diffusely reflected by the ceramic washbasin 11 or the like.

  On the other hand, as shown in FIG. 2B, when the detection light is reflected by the specular reflector 2b, the polarization state is maintained, so that the reflected light is substantially only in the S wave. Accordingly, the reflected light is blocked by the second polarizing member 44. That is, the reception of specular reflection light by the light receiving element 42 is suppressed. Thereby, the erroneous water discharge by specular reflected light is also suppressed.

  In this way, the S-wave infrared light included in the reflected light is a component of specular reflection light, and the P-wave infrared light included in the reflected light can be considered as a component of diffuse reflection light. . The control unit 20 detects the presence / absence of an object using the component (third polarization) included in the diffuse reflection light without using the component of the specular reflection light (second polarization).

Drawing 3 (a) and Drawing 3 (b) are block diagrams showing a part of faucet device concerning an embodiment.
As illustrated in FIG. 3A, for example, ambient light such as illumination light or sunlight may be specularly reflected by the specular reflector 2 b and may enter the second polarizing member 44. Ambient light is unpolarized light. For this reason, the P wave component included in the ambient light passes through the second polarizing member 44 and is received by the light receiving element 42. Therefore, ambient light becomes noise and may cause a malfunction of the faucet device 10.

  For example, when the wavelength band of the light receiving element 42 is wider than the wavelength band of the detection light and the wavelength band of the light receiving element 42 extends from the infrared region to the visible light region, the second polarization of the second polarizing member 44 is blocked. A configuration in which the possible wavelength band is only the same infrared region as the detection light is conceivable. In such a configuration, with respect to the light in the infrared region of the ambient light, the S wave is blocked by the second polarizing member 44, and only the P wave in the infrared region of the ambient light is incident on the light receiving element 42. On the other hand, the light in the visible light region of the ambient light is incident on the light receiving element 42 without being blocked by the second polarizing member 44. For this reason, the amount of ambient light received increases.

  On the other hand, in the faucet device 10 according to the present embodiment, the wavelength band in which the second polarizing member 44 can block the second polarized light is wider than the wavelength band in which the light receiving element 42 can receive light. Thereby, also about the light of the visible light region of ambient light, the S-wave component can be blocked by the second polarizing member 44, and ambient light incident on the light receiving element 42 can be suppressed. Since ambient light such as illumination light and sunlight contains a large amount of visible light components, the second polarized light component should be blocked even in the visible light region as in the faucet device 10 according to the present embodiment. Thus, noise can be effectively suppressed.

  As shown in FIG. 3B, for example, when ambient light such as illumination light or sunlight is incident on the reflector 2c such as water or glass at an angle called Brewster angle, it is included in the ambient light. The P wave component transmitted through the reflector 2c, and only the S wave component included in the ambient light is reflected by the reflector 2c.

  In particular, when the faucet 13 is disposed on the rear side of the bowl surface 11a and the second polarizing member 44 is provided in an inclined state with respect to the horizontal plane, the direction opposite to the faucet 13 is opposite to the second polarizing member 44. The light receiving element 42 is located on the direction side (the back side when viewed from the front side). Therefore, ambient light such as illumination light and sunlight is easily reflected from the direction (front side) toward the faucet 13 to water, glass, etc. in the bowl surface 11a and is incident on the light receiving unit 40.

  In order to suppress visible light noise, it is possible to add a visible light cut member in front of the light receiving element 42 or to mold the light receiving element 42 itself with a visible light cut resin. It is difficult to completely match the wavelength band of the received light with the wavelength band of the detection light of the light projecting element 32. For this reason, the wavelength band for receiving light is not limited to the wavelength band of the detection light, and noise due to ambient light is received. This is not limited to the wavelength band of visible light, but applies to all wavelength bands other than the wavelength band of the detection light of the light projecting element 32.

  At this time, in the faucet device 10 according to the present embodiment, the first polarized light and the second polarized light are linearly polarized light that vibrates in a direction parallel to the horizontal plane, and the S wave can be blocked by the second polarizing member 44. ing. Therefore, when the ambient light is reflected at the Brewster angle, the S-wave ambient light can be appropriately blocked by the second polarizing member 44. Thereby, it can suppress more reliably that ambient light will inject into the light receiving element 42. FIG.

FIG. 4 is a flowchart showing the operation of the faucet device according to the embodiment.
As illustrated in FIG. 4, the control unit 20 of the faucet device 10 waits for a predetermined time when the operation is started, for example, by turning on the power (step S <b> 101 in FIG. 4). The predetermined time is, for example, 0.5 seconds. The waiting time is not limited to this and may be any time.

  After waiting for a predetermined time, the control unit 20 supplies current to the light projecting element 32, thereby causing the light projecting element 32 to project detection light (step S102 in FIG. 4). The controller 20 causes the light projecting element 32 to project light a predetermined number of times, for example, by supplying a pulsed current (voltage) to the light projecting element 32.

  The control unit 20 determines whether or not the amount of light received by the light receiving element 42 is equal to or greater than a predetermined threshold based on the reception signal input from the light receiving unit 40 after performing a predetermined number of pulse projections. More specifically, it is determined whether or not the integrated value of the amount of light received with a predetermined number of pulse projections is greater than or equal to a threshold value.

  When the amount of received light is equal to or greater than the threshold value, the control unit 20 determines that it is sensing. That is, it detects that there is an object. And the control part 20 determines with non-sense, when the light reception amount is less than a threshold value. That is, it detects that there is no object.

  The control unit 20 determines whether or not an object is sensed in the current detection operation with a predetermined number of pulse projections (step S103 in FIG. 4).

  When it determines with having sensed, the control part 20 determines whether it is still water stop (step S104 of FIG. 4).

  When it determines with it being under water stop, the control part 20 opens the solenoid valve 16, starts water discharge, and returns to the process of step S101 (step S105 of FIG. 4). On the other hand, when it determines with the control part 20 not being still water in step S104, it returns to the process of step S101 as it is.

  When it determines with non-sense in step S103, the control part 20 determines whether it is discharging water (step S106 of FIG. 4).

  When determining that the water is being discharged, the control unit 20 closes the electromagnetic valve 16 and terminates the water discharge, and then returns to the process of step S101 (step S107 in FIG. 4). On the other hand, if the control unit 20 determines in step S106 that the water is not discharged, the process returns to step S101 as it is.

  The control unit 20 repeats the above processing. Thereby, in the faucet device 10, when the user brings his hand or the like closer to the spout 13a, water discharge is automatically started from the spout 13a, and when the user moves his hand away from the spout 13a, the spout Water discharge from 13a is terminated.

  As described above, in the faucet device 10 according to the present embodiment, the wavelength band in which the second polarizing member 44 can block the second polarized light has a wavelength other than the wavelength band of the light receiving element 42. Thus, even when the wavelength band that can be received by the light receiving element 42 has a wavelength other than the wavelength band of the detection light of the light projecting element 32, the second component of the second polarization of light other than the detection light is also second. It can be blocked by the polarizing member 44. Thereby, the incident amount of light other than the detection light incident on the light receiving element 42 can also be reduced. Without adding a new member, circuit, or control, it is possible to suppress malfunction of the faucet device 10 due to light other than detection light. Therefore, it is possible to provide the faucet device 10 that can suppress the influence of light other than the detection light with a simple configuration.

  The wavelength band in which the second polarizing member 44 can block the second polarized light is only one of the short wavelength side (ultraviolet side) or the long wavelength side (far infrared side) of the wavelength band that can be received by the light receiving element 42. Even in a wide case, it is possible to reduce the amount of incident light other than the detection light incident on the light receiving element 42. Then, the wavelength band in which the second polarizing member 44 can block the second polarized light is made wider than the wavelength band in which the light receiving element 42 can receive light, and overlaps the entire wavelength band in which the light receiving element 42 can receive light. Thus, the amount of incident light other than the detection light incident on the light receiving element 42 can be more reliably reduced.

  In the faucet device 10, the first polarized light and the second polarized light are linearly polarized light that vibrates in a direction parallel to the horizontal plane. That is, the light that vibrates in a direction parallel to the horizontal plane can be blocked by the second polarizing member 44. Thereby, it can suppress more reliably that the ambient light etc. which reflected with the Brewster angle by the water surface, glass, etc. inject into the light receiving element 42. FIG. Therefore, malfunction of the faucet device 10 due to light other than detection light can be more reliably suppressed.

  In the faucet device 10, the second polarizing member 44 is a metal wire grid polarizing plate. As a result, the second polarizing member 44 having a wider wavelength band capable of blocking the second polarized light than the wavelength band of the light receiving element 42 can be manufactured relatively easily. Further, since metal is difficult to transmit ultraviolet rays, deterioration of resin parts and the like inside the photoelectric sensor 18 can be suppressed. More specifically, when the resin constituting the light projecting element 32 and the light receiving element 42 is deteriorated by ultraviolet rays, the detection accuracy is deteriorated. However, the presence of a metal in the front can reduce the incident light amount of ultraviolet rays. . Further, by exhibiting polarization performance even in the wavelength region of ultraviolet rays, it is possible to further block light and further reduce the amount of incident light.

  In the said embodiment, the faucet device 10 which supplies water to the faucet 13 and enables hand-washing etc. is shown as an example of the water discharging device. The water discharging device is not limited to this, and may be, for example, a water discharging device that discharges water soap in response to detection of an object such as a hand. The water discharged from the water discharging device is not limited to tap water and may include liquid such as water soap.

The embodiment of the present invention has been described above. However, the present invention is not limited to these descriptions. As long as the features of the present invention are provided, those skilled in the art appropriately modified the design of the above-described embodiments are also included in the scope of the present invention. For example, the shape, dimensions, material, arrangement, and the like of each element included in the faucet device 10 are not limited to those illustrated, and can be changed as appropriate.
Moreover, each element with which each embodiment mentioned above is provided can be combined as long as technically possible, and the combination of these is also included in the scope of the present invention as long as it includes the features of the present invention.

  2a diffuse reflector, 2b specular reflector, 2c reflector, 10 faucet device, 11 wash basin, 11a bowl surface, 12 wash basin counter, 13 faucet, 13a spout, 14 water supply channel, 15 drainage channel, 16 solenoid valve , 17 connection cable, 18 photoelectric sensor, 20 control unit, 30 light projecting unit, 32 light projecting element, 34 first polarizing member, 40 light receiving unit, 42 light receiving element, 44 second polarizing member

Claims (3)

A water discharge part having a water discharge port for discharging water;
A water supply channel for leading water from a water supply source to the water outlet;
An on-off valve for opening and closing the water supply channel;
A photoelectric sensor that projects detection light, receives reflected light of the detection light, and outputs a reception signal corresponding to the amount of received light of the reflected light;
A controller that detects the presence or absence of an object based on the received signal, and controls opening and closing of the on-off valve according to the detection result of the object;
With
The photoelectric sensor is
A light projecting element that projects the detection light;
A light receiving element for receiving the reflected light;
A first polarizing member that is provided in front of the light projecting element, transmits a first polarized light included in the detection light, and blocks a polarized light different from the first polarized light;
Provided in front of the light receiving element, out of the light included in the reflected light, the first polarized light is mirror-reflected to block the second polarized light and is different from the second polarized light. A second polarizing member that transmits three-polarized light;
Have
The wavelength band that can be received by the light receiving element has a wavelength other than the wavelength band of the detection light of the light projecting element,
The water discharging apparatus according to claim 1, wherein the wavelength band in which the second polarizing member can block the second polarized light has a wavelength other than the wavelength band of the light receiving element.   The water discharging apparatus according to claim 1, wherein the first polarized light and the second polarized light are linearly polarized light that vibrates in a direction parallel to a horizontal plane.   The water discharging apparatus according to claim 1, wherein the second polarizing member is a metal wire grid polarizing plate.

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