Sensor unit for faucet

Abstract

To provide a sensor unit for a faucet that is less likely to cause false detection even when dirt or water droplets adhere to a sensor cover.SOLUTION: A sensor unit 10 for a faucet comprises a reflection-type photoelectric sensor 11 that detects the extension of a user's hand, and a light-transmissive sensor cover 12 that covers the photoelectric sensor 11. The photoelectric sensor 11 has a light-emitting part 11B that emits light to the outside through the sensor cover 12, and a light-receiving part 11C that receives reflected light from the light emitted by the light-emitting part 11B through the sensor cover 12. The sensor unit 10 for a faucet further comprises a light-shielding part 12C that suppresses the internally reflected light within the cover, which is reflected from a cover surface AS of the sensor cover 12, from reaching the light-receiving part 11C, out of the light emitted from the light-emitting part 11B.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a sensor unit for a faucet, and more particularly to a sensor unit for a faucet having a reflective photoelectric sensor that detects the presentation of an object to be detected, and a light-transmitting sensor cover that covers the photoelectric sensor. [Background technology]

[0002] Patent Document 1 discloses an automatic faucet equipped with a sensor unit capable of contactlessly detecting the presentation of a user's hand. This sensor unit has a reflective photoelectric sensor (infrared sensor) and a sensor cover made of a light-transmitting resin material that covers the photoelectric sensor. The photoelectric sensor has a light-projecting section that projects light to the outside through the sensor cover, and a light-receiving section that receives the projected light that hits an object and is reflected through the sensor cover. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6052491 Summary of the Invention [Problem to be solved by the invention]

[0004] In the above-mentioned conventional technology, there is a risk of false detection occurring when dirt or water droplets adhere to the sensor cover, causing the light projected from the light-projecting unit to be reflected by the surface of the cover and received by the light-receiving unit. Therefore, the present invention provides a faucet sensor unit that is less likely to cause false detection even if dirt or water droplets adhere to the sensor cover. [Means for solving the problem]

[0005] In order to solve the above problems, the faucet sensor unit of the present invention takes the following measures.

[0006] In other words, the first invention of the present invention is a faucet sensor unit having a reflective photoelectric sensor that detects the presentation of an object to be detected and a light-transmitting sensor cover that covers the photoelectric sensor, wherein the photoelectric sensor has a light-projecting section that projects light to the outside through the sensor cover and a light-receiving section that receives the reflected light of the light projected from the light-projecting section through the sensor cover, and the faucet sensor unit further has a light-shielding section that prevents intra-cover reflected light that is reflected inwardly by the cover surface of the sensor cover from reaching the light-receiving section, of the light projected from the light-projecting section.

[0007] According to the first invention, a sensor cover used in a wet environment is prone to have dirt and water droplets on its cover surface due to splashes of water, etc. When dirt or water droplets adhere to the cover surface of the sensor cover, a part of the light projected from the light-projecting unit is reflected by the cover surface as light reflected within the cover, and is likely to travel toward the light-receiving unit. However, by providing a light-shielding unit, it is possible to appropriately prevent the light reflected within the cover from reaching the light-receiving unit and causing a false detection.

[0008] The second invention of the present invention is a sensor unit for a faucet, in which, in the first invention described above, the light-shielding portion is arranged so as to separate a light-projecting area directly facing the light-projecting portion of the sensor cover from a light-receiving area directly facing the light-receiving portion.

[0009] According to the second aspect of the present invention, it is possible to more appropriately prevent the light reflected within the cover from reaching the light receiving section.

[0010] A third invention of the present invention is the faucet sensor unit according to the first or second invention, wherein the light blocking portion is integrally formed with the sensor cover.

[0011] According to the third aspect of the present invention, it is possible to obtain a configuration that is less likely to cause erroneous detection without complicating the structure of the faucet sensor unit. In addition, since the position of the light blocking part relative to the sensor cover can be fixed, it is possible to more appropriately prevent the reflected light from within the cover from reaching the light receiving part.

[0012] A fourth aspect of the present invention is the faucet sensor unit according to the first or second aspect, wherein the light blocking portion is arranged flush with the cover surface of the sensor cover.

[0013] According to the fourth aspect of the present invention, the light-shielding portion does not protrude from the cover surface of the sensor cover, so that the projected light and the reflected light are less likely to be blocked by the light-shielding portion. Also, since the cover surface does not protrude, the cover surface is less likely to become clogged with dirt or water droplets. Therefore, the light-shielding portion can be appropriately provided so as not to impair the detection function of the faucet sensor unit. [Brief description of the drawings]

[0014] [Figure 1] 1 is a perspective view showing an outline of a faucet sensor unit according to a first embodiment; [Diagram 2] FIG. 2 is an enlarged view taken along the arrow II in FIG. [Diagram 3] FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0016] First Embodiment (Schematic configuration of faucet sensor unit 10) First, the configuration of a faucet sensor unit (hereinafter, sensor unit) 10 according to a first embodiment of the present invention will be described with reference to Figures 1 to 4. In the following description, when directions such as front, back, top, bottom, left, and right are indicated, they refer to the respective directions shown in each figure.

[0017] The directions shown in each figure are those seen by a user standing in front of the automatic faucet 1 on which the sensor unit 10 is installed. In the following description, when no specific reference figure is shown or when no reference figure has a corresponding reference symbol, any of Figures 1 to 4 will be referred to as appropriate.

[0018] As shown in Fig. 1, the sensor unit 10 according to this embodiment is incorporated into an automatic faucet 1 that is installed on the top plate at the rear of the washstand. The automatic faucet 1 includes a faucet body 2 that extends in a gooseneck shape from the top plate at the rear of the washstand, and a water outlet pipe 3 that passes through the inside of the faucet body 2.

[0019] As shown in Fig. 2, the water discharge pipe 3 is provided so that the water discharge port 3A at its tip is exposed to the outside from the opening 2A at the end of the gooseneck-shaped extension of the faucet body 2. The automatic faucet 1 further includes a sensor unit 10 provided within the opening 2A so as to be exposed to the outside alongside the water discharge port 3A.

[0020] The sensor unit 10 has a reflective photoelectric sensor 11 that can detect without contact that a user's hand is placed in front of the water outlet 3A, and a sensor cover 12 that covers the photoelectric sensor 11. When the sensor unit 10 detects that a user's hand is placed in front of the water outlet 3A, it transmits a detection signal to a control device (not shown).

[0021] When the control device (not shown) determines based on the received detection signal that the user's hand is held out in front of the water outlet 3A, it sends a control signal to a solenoid valve (not shown) to switch the solenoid valve from a closed state to an open state, causing water to flow from a water supply pipe (not shown) to the water outlet pipe 3, and the water is discharged from the water outlet 3A to the outside.

[0022] When a control device (not shown) determines that the user's hand has been removed from in front of the water outlet 3A based on the detection signal sent from the sensor unit 10, it sends a control signal to a solenoid valve (not shown) to switch the solenoid valve from an open state to a closed state, thereby stopping the discharge of water from the water outlet 3A.

[0023] The sensor unit 10 is arranged inside the opening 2A of the faucet body 2, lined up at a position in front of the water outlet 3A. This allows the sensor unit 10 to accurately detect when a user holds out their hand in front of the water outlet 3A. However, because the sensor unit 10 is used in a wet environment as described above, it is configured such that dirt and water droplets are likely to adhere to the cover surface AS of the sensor cover 12 due to the effects of water splashes when a user washes their hands or objects directly below the water outlet 3A.

[0024] If dirt or water droplets adhere to the cover surface AS of the sensor cover 12, the light emitted from the photoelectric sensor 11 is likely to be reflected inward by the dirty or water droplet-adhered cover surface AS of the sensor cover 12. If this reflected light is received by the photoelectric sensor 11, there is a risk that a control device (not shown) will erroneously detect that a user's hand is placed in front of the water outlet 3A, even though the user's hand is not actually placed in front of the water outlet 3A.

[0025] In order to prevent this erroneous detection, the sensor unit 10 is provided with a light-shielding portion 12C that can suppress the light reflected inwardly by the cover surface AS of the sensor cover 12 from being received by the photoelectric sensor 11. The light-shielding portion 12C is integrally built into the sensor cover 12.

[0026] The following describes in detail the specific configuration of each part of the sensor unit 10. As shown in Figures 3 and 4, the photoelectric sensor 11 has a substrate 11A attached to the faucet body 2, and a light-projecting unit 11B and a light-receiving unit 11C provided on the substrate 11A in an electrically connected state.

[0027] The substrate 11A is formed in a horizontally elongated flat plate shape extending in the left-right direction in the figure. The light-projecting section 11B and the light-receiving section 11C are provided separately at left and right positions sandwiching the center of the substrate 11A in the left-right direction in the figure. The light-projecting section 11B includes a light-emitting element that projects light such as infrared light or visible light toward the outside. The light-receiving section 11C includes a light-receiving element that receives reflected light of the light projected from the light-projecting section 11B.

[0028] Sensor cover 12 is made of a light-transmitting resin material. Sensor cover 12 has a container shape that envelops light-projecting unit 11B and light-receiving unit 11C provided on substrate 11A between substrate 11A and sensor cover 12. Specifically, sensor cover 12 has cover top plate portion 12A in the shape of a horizontally long flat plate facing substrate 11A, and peripheral side plate portion 12B extending in a cylindrical shape from the periphery of cover top plate portion 12A.

[0029] The sensor cover 12 is set so that the substrate 11A fits into the cylinder of the peripheral side plate portion 12B. The sensor cover 12 is fixed integrally with the substrate 11A by fastening it to a mounting base (not shown) that supports the substrate 11A. By the above fixing, the sensor cover 12 is set so that its cover top plate portion 12A faces the light projecting portion 11B and the light receiving portion 11C provided on the substrate 11A. The sensor cover 12 is also set so that its peripheral side plate portion 12B surrounds the light projecting portion 11B and the light receiving portion 11C provided on the substrate 11A.

[0030] A light-shielding portion 12C is incorporated in the sensor cover 12, extending in a strip shape along the center in the left-right direction in the figure so as to divide the cover top plate portion 12A into left and right portions. The light-shielding portion 12C is made of a resin material with lower light transmittance than the sensor cover 12. Specifically, the light-shielding portion 12C is made of a black resin material that can block the light on its surface without transmitting it even if the light projected from the light-projecting portion 11B hits the light-shielding portion 12C.

[0031] The light shielding portion 12C is provided so as to extend continuously over the entire area in the front-rear direction from the edge on the front side to the edge on the back side of the cover top plate portion 12A in the figure. The light shielding portion 12C is also provided on the cover top plate portion 12A and on the front side of the peripheral side plate portion 12B in the figure so as to extend in a band shape along the center in the left-right direction in the figure.

[0032] In detail, the light shielding portion 12C is provided so as to extend continuously over the entire area in the vertical direction from the lower edge to the upper edge of the front side of the peripheral side plate portion 12B in the figure. The light shielding portion 12C is integrally formed with the sensor cover 12 so as to be flush with the sensor cover 12.

[0033] Specifically, the light shielding portion 12C is formed in an L-shaped plate shape that extends along the cover top plate portion 12A and the peripheral side plate portion 12B to have the same plate thickness as these portions. The light shielding portion 12C is integrally molded with the sensor cover 12 to be flush with the cover surface AS of the cover top plate portion 12A and the cover surface AS of the front side portion of the peripheral side plate portion 12B in the figure.

[0034] Specifically, the light-shielding portion 12C is disposed so as to separate the light-projecting area A1 directly facing the light-projecting portion 11B of the cover top plate portion 12A from the light-receiving area A2 directly facing the light-receiving portion 11C. More specifically, the light-shielding portion 12C is not disposed at each position directly facing the light-projecting portion 11B and the light-receiving portion 11C, but is disposed so as to extend in a band shape passing between them with a band width narrower than the spacing between them.

[0035] Even if dirt or water droplets adhere to the cover surface AS of the sensor cover 12 and reflection occurs at the cover surface AS, the light-shielding portion 12C prevents the reflected light (light reflected within the cover) from traveling through the sensor cover 12 and being received by the photoelectric sensor 11. Specifically, as shown in FIG. 4, when light such as infrared light or visible light is projected from the light-projecting portion 11B, the light is irradiated to the outside through the cover top plate portion 12A of the sensor cover 12.

[0036] When the light emitted to the outside hits a detection target such as a user's hand, the light is reflected and received by light receiving unit 11C through cover top plate portion 12A of sensor cover 12. However, if dirt or water droplets adhere to cover surface AS of sensor cover 12, some of the light projected from light projecting unit 11B may be reflected by cover surface AS of sensor cover 12 that has dirt or water droplets attached thereto.

[0037] At that time, the light reflected by the cover surface AS (inner cover reflected light) may travel along the cover top plate portion 12A, repeatedly reflecting within the cover top plate portion 12A. However, the light-shielding portion 12C is provided on the cover top plate portion 12A to separate the light-projecting area A1 from the light-receiving area A2, so that the inner cover reflected light is blocked from entering the light-receiving area A2 from the light-projecting area A1. As a result, the light-receiving portion 11C can appropriately prevent the inner cover reflected light from being received.

[0038] Specifically, the light-shielding portion 12C is arranged flush with the cover surface AS of the cover top plate portion 12A and does not protrude from the cover surface AS. This makes it difficult for the light projected from the light-projecting portion 11B to the outside and the light reflected by the detection object to be blocked by the light-shielding portion 12C.

[0039] In addition, since the light shielding portion 12C does not create a protrusion on the cover surface AS, dirt and water droplets are less likely to clog the cover surface AS. Therefore, the light shielding portion 12C can be appropriately provided so as not to impair the detection function of the sensor unit 10.

[0040] In addition, since the light-shielding portion 12C is configured not to transmit light, it can be used for adjusting the light-projecting range of the light-projecting portion 11B and the light-receiving range of the light-receiving portion 11C by widening or narrowing the area where the light-shielding portion 12C is arranged. The light-shielding portion 12C may have any shape that is provided at least on the cover top plate portion 12A, but by having an L-shaped plate shape that is also provided on the peripheral side plate portion 12B, the light-shielding portion 12C can be easily attached to a molding die when being molded integrally with the sensor cover 12. As a result, the sensor cover 12 can be appropriately molded integrally with the light-shielding portion 12C.

[0041] To summarise the above, the sensor unit 10 according to the first embodiment has the following configuration: Note that in the following, the reference characters in parentheses correspond to the respective components shown in the above embodiment.

[0042] That is, the faucet sensor unit (10) has a reflective photoelectric sensor (11) that detects the presentation of an object to be detected, and a light-transmitting sensor cover (12) that covers the photoelectric sensor (11). The photoelectric sensor (11) has a light-projecting unit (11B) that projects light to the outside through the sensor cover (12), and a light-receiving unit (11C) that receives, through the sensor cover (12), the reflected light of the light projected from the light-projecting unit (11B).

[0043] The faucet sensor unit (10) further includes a light-shielding portion (12C) that prevents light projected from the light-projecting portion (11B) from reaching the light-receiving portion (11C) through the inner-cover reflected light that is reflected inwardly from the cover surface (AS) of the sensor cover (12). As described above, the sensor cover (12) used in a wet environment is prone to stains and water droplets due to splashes of water, etc., adhering to its cover surface (AS).

[0044] When dirt or water droplets adhere to the cover surface (AS) of the sensor cover (12), part of the light projected from the light-projecting unit (11B) is reflected by the cover surface (AS) as in-cover reflected light, and is likely to travel toward the light-receiving unit (11C). However, by providing the light-shielding unit (12C), it is possible to appropriately prevent the in-cover reflected light from reaching the light-receiving unit (11C) and causing a false detection.

[0045] In addition, the light-shielding portion (12C) is disposed to separate the light-projecting area (A1) directly facing the light-projecting portion (11B) of the sensor cover (12) from the light-receiving area (A2) directly facing the light-receiving portion (11C). With the above configuration, it is possible to more appropriately prevent the light reflected within the cover from reaching the light-receiving portion (11C).

[0046] In addition, the light-shielding portion (12C) is molded integrally with the sensor cover (12). With the above configuration, it is possible to obtain a configuration that is less likely to cause erroneous detection without complicating the structure of the faucet sensor unit (10). In addition, since the position of the light-shielding portion (12C) relative to the sensor cover (12) can be fixed, it is possible to more appropriately prevent the light reflected within the cover from reaching the light-receiving portion (11C).

[0047] In addition, the light-shielding portion (12C) is provided so as to be aligned flush with the cover surface (AS) of the sensor cover (12). With the above configuration, the light-shielding portion (12C) does not protrude from the cover surface (AS) of the sensor cover (12), so that the projected light and the reflected light are less likely to be blocked by the light-shielding portion (12C). In addition, since the cover surface (AS) does not protrude, the cover surface (AS) is less likely to become clogged with dirt and water droplets. Therefore, the light-shielding portion (12C) can be appropriately provided so as not to impair the detection function of the faucet sensor unit (10).

[0048] Other embodiments Although one embodiment of the present invention has been described above, the present invention can be embodied in various forms as described below in addition to the above embodiment.

[0049] 1. The faucet sensor unit of the present invention may be attached to the faucet body, or may be configured to be installed around the sink apart from the faucet body. Also, the faucet sensor unit may be arranged so that the light-projecting unit projects light downward, or may be arranged so that the light-projecting unit projects light upward, to the side, forward, or toward the back.

[0050] 2. The light-shielding part may be configured to prevent the light reflected from inside the cover, which is reflected on the cover surface of the sensor cover, from reaching the light-receiving part, and may be configured to be made of a black light-absorbing material or a material that reflects the light reflected from inside the cover in a direction that prevents the light reflected from reaching the light-receiving part. The light-shielding part may be configured to completely block the light reflected from inside the cover from reaching the light-receiving part, or may be configured to allow the light reflected from inside the cover to pass through to the extent that it does not cause erroneous detection of the detection target.

[0051] 3. The light-shielding part may be integrally molded with the sensor cover, or may be bonded or fitted to the sensor cover to be integrated with it. Also, the light-shielding part may be bonded or fitted to the substrate of the photoelectric sensor to be integrated with it, instead of the sensor cover.

[0052] The light-shielding portion does not necessarily have to be integrated with the sensor cover or the substrate of the photoelectric sensor, and may be detachably attached to them. The light-shielding portion may be arranged to separate the light-projecting area facing the light-projecting portion of the sensor cover and the light-receiving area facing the light-receiving portion in the plate thickness direction, or may be arranged in a layer along the front cover surface and / or back cover surface of the sensor cover to block light reflected within the cover toward the light-receiving portion.

[0053] The light shielding portion may be configured to protrude from the front cover surface and / or the back cover surface of the sensor cover. The material of the light shielding portion is not particularly limited, and may be a metal material as well as a resin material.

[0054] The embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the description of the embodiments described above, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0055] 1...automatic faucet, 2...faucet body, 2A...opening, 3...discharge pipe, 3A...discharge port, 10...faucet sensor unit, 11...photoelectric sensor, 11A...circumference board, 11B...light-emitting section, 11C...light-receiving section, 12...sensor cover, 12A...cover top plate, A1...light-emitting area, A2...light-receiving area, 12B...surrounding side plate, 12C...light-shielding section, AS...cover surface

Claims

1. A sensor unit for a faucet, comprising a reflective photoelectric sensor for detecting the presence of a detection object and a light-transmitting sensor cover for covering the photoelectric sensor, The photoelectric sensor has a light-projecting unit that projects light to the outside through the sensor cover, and a light-receiving unit that receives reflected light of the light projected from the light-projecting unit through the sensor cover, The faucet sensor unit further has a light-shielding section that prevents light reflected within the cover, which is reflected inwardly from the cover surface of the sensor cover, from reaching the light-receiving section, out of the light projected from the light-projecting section.

2. The faucet sensor unit according to claim 1, A sensor unit for a faucet, in which the light-shielding portion is arranged to separate a light-projecting area directly facing the light-projecting portion of the sensor cover from a light-receiving area directly facing the light-receiving portion.

3. The faucet sensor unit according to claim 1 or 2, The faucet sensor unit has the light-shielding portion integrally molded with the sensor cover.

4. The faucet sensor unit according to claim 1 or 2, A faucet sensor unit, wherein the light-shielding portion is arranged flush with the cover surface of the sensor cover.

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