JP2010053575A - Automatic water faucet device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an automatic water faucet device capable of preventing a cover for protection, or the like, from being misdetected. <P>SOLUTION: In this automatic water faucet device, an interval between an installed chip section 22a on the light-receiving part side in a light-projecting part which is a section for radiating light in the light-projecting part and being the closest to a light-receiving part and an installed chip section 30a on a light-projecting part side in the light-receiving part which is a section for receiving the reflected light in the light-receiving part and being the closest to the light-projecting part is set at such a distance that an area is formed which is in common by intersecting a light-projecting area 40 with a light-receiving area 41 mutually in an area to be detected. Even when the light positioned on the outermost-side section out of the light radiated from the light-projecting part is reflected by the cover 7, the interval between them is set to be a distance such that prevents the reflected light from being received by the light-receiving part. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an automatic faucet device that detects an object to be cleaned such as a human hand and automatically discharges water.

Conventionally, this type of automatic faucet device includes an optical unit that is buried in a position near the water outlet and facing the detection region. This optical unit includes a light projecting unit that projects light toward a human hand or the like that has been pushed out to the detection region, and a light receiving unit that receives reflected light reflected from the human hand or the like ( For example, see Patent Document 1). And the conventional automatic faucet device may be equipped with the cover for light transmission protection in order to protect the surface of a light projection part and a light-receiving part from dirt.
Japanese Patent Laid-Open No. 5-31709

  However, although this protective cover covers the front surface of the light projecting part and the light receiving part to prevent dirt and contribute to ensuring the detection performance, the automatic faucet device is attached to the protective cover and the protective cover. In other words, the light reflected by the water droplets) is received and erroneously detected. If the protective cover is erroneously detected in this way, there is a problem that water is discharged unexpectedly, or once such a situation occurs, water continues to come out.

  In order to prevent the reflected light from being generated by the protective cover, it is desirable to install the protective cover so that there is no gap between the light projecting part and the light receiving part and the inner surface of the protective cover. Actually, it is difficult to install in a desired state due to manufacturing errors of each part, assembly errors in the assembly process, and the like.

  Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide an automatic faucet device that can prevent erroneous detection of a protective cover or the like.

In order to achieve the above object, the following technical means are adopted. That is, the invention according to claim 1 projects light that radiates light toward a detection target area as a detection target so as to form a predetermined radiation angle (α) to form a light projection area (40). A light receiving portion (30) that forms a light receiving area (41) having a predetermined light receiving angle (β) so as to receive reflected light reflected by the light emitted from the light projecting portion and the object. ) And a light-transmitting cover (7) provided so as to cover the front side of the light projecting unit and the light receiving unit on the detection target area side, and the reflected light reflected by the hand entering the light projecting area is received by the light receiving unit Is an invention related to an automatic faucet device that automatically drains water when it receives light,
A tip portion (20a, 22a) closest to the light receiving portion that emits light from the light projecting portion, and a tip portion (30a) closest to the light projecting portion that receives the reflected light of the light receiving portion. The installation interval of
In the detection target area, the light projecting area and the light receiving area intersect to be set to a distance that forms a shared area,
Even if light traveling through the outermost part of the light emitted from the light projecting part is reflected by the cover and the adhering matter attached to the cover, the reflected light is set to a distance at which it is not received by the light receiving part. Features.

  According to this invention, even if the light radiated from the light projecting unit is reflected by the cover, the light receiving unit reflects the reflected light by arranging and arranging the installation interval between the light projecting unit and the light receiving unit as described above. Therefore, an automatic water faucet device that can prevent erroneous detection of a light emitting unit and a cover for protecting the light receiving unit is obtained.

According to the second aspect of the present invention, the installation interval in the first aspect is D, the predetermined radiation angle is α, and the inclination angle of the axis (26) of the light projecting portion with respect to the perpendicular direction of the cover inner surface (7a) is θ1. When the distance from the tip part (20a, 22a) of the light projecting part to the cover is g1, and the distance from the tip part (30a) of the light receiving part to the cover is g2,
The installation interval (D) is preferably set so as to satisfy the relationship represented by the following Expression 7.

  According to this, by setting the installation interval (D) between the light projecting unit and the light receiving unit so as to satisfy Expression 7 in consideration of the inclination of the light projecting unit and the size of the radiation angle, the light is emitted from the light projecting unit. Even when the light located at the outermost part of the light is reflected by the cover, the light can be controlled to be reflected at a position where it cannot be received by the light receiving unit. Accordingly, a simple method based on each condition of the light projecting unit can be provided as a design for preventing erroneous detection of the cover.

In the invention according to claim 3, the installation interval in claim 1 is D, the predetermined light receiving angle is β, and the inclination angle of the axis (36) of the light receiving portion with respect to the perpendicular direction of the cover inner surface (7a) is θ2. When the distance from the tip part (20a, 22a) of the light projecting part to the cover is g1, and the distance from the tip part (30a) of the light receiving part to the cover is g2,
The installation interval (D) is preferably set so as to satisfy the relationship represented by the following Expression 8.

  According to this, the light radiated from the light projecting unit is set by setting the installation interval (D) between the light projecting unit and the light receiving unit so as to satisfy Expression 8 in consideration of the inclination of the light receiving unit and the size of the light receiving angle. Of these, even when the light located at the outermost part is reflected by the cover, the light can be controlled to be reflected at a position where it cannot be received by the light receiving unit. Thereby, the simple method based on each condition of a light-receiving part can be provided as a design concerning the erroneous detection of a cover.

In the invention according to claim 4, the installation interval in claim 1 is D, the predetermined radiation angle is α, and the inclination angle of the axis (26) of the light projecting portion with respect to the perpendicular direction of the cover inner surface (7a) is θ1. The distance from the tip part (20a, 22a) of the light projecting part to the cover is g1, the distance from the tip part (30a) of the light receiving part to the cover is g2, the refractive index of air is n1, and the cover When the refractive index of n is n2 and the thickness dimension of the cover is t,
The installation interval (D) is preferably set so as to satisfy the relationship represented by the following Expression 9.

  According to this, by setting the installation interval (D) between the light projecting unit and the light receiving unit so as to satisfy Equation 9 in consideration of the inclination of the light projecting unit and the size of the radiation angle, the light is emitted from the light projecting unit. Even when the light located at the outermost part of the light is reflected by dirt or the like attached to the outer surface of the cover, the light can be controlled to be reflected at a position where it cannot be received by the light receiving unit. Thereby, the simple method based on each condition of a light projection part and the deposit | attachment of an outer surface of a cover can be provided as a design which concerns on the erroneous detection of a cover.

In the invention according to claim 5, the installation interval in claim 1 is D, the predetermined light receiving angle is β, and the inclination angle of the axis (36) of the light receiving portion with respect to the perpendicular direction of the cover inner surface (7a) is θ2. The distance from the tip part (20a, 22a) of the light projecting part to the cover is g1, the distance from the tip part (30a) of the light receiving part to the cover is g2, the refractive index of air is n1, When the refractive index is n2 and the thickness dimension of the cover is t,
The installation interval (D) is preferably set so as to satisfy the relationship represented by the following Expression 10.

  According to this, the light emitted from the light projecting unit is set by setting the installation interval (D) between the light projecting unit and the light receiving unit so as to satisfy Equation 10 in consideration of the inclination of the light receiving unit and the size of the light receiving angle. Of these, even when the light located at the outermost part is reflected by dirt or the like attached to the outer surface of the cover, the light can be controlled to be reflected at a position where light cannot be received by the light receiving unit. As a result, a simple method based on the conditions of the light receiving unit and the deposits on the outer surface of the cover can be provided as a design for preventing erroneous detection of the cover.

In the invention according to claim 6, the installation interval in claim 1 is D, the predetermined radiation angle is α, and the inclination angle of the axis (26) of the light projecting portion with respect to the normal direction of the cover inner surface (7a) is θ1. The distance from the tip part (20a, 22a) of the light projecting part to the cover is g1, the distance from the tip part (30a) of the light receiving part to the cover is g2, the refractive index of air is n1, and the cover When the refractive index of n2 is n2, the thickness dimension of the cover is t, and the length of the attachment surface of water drops attached to the cover is a predetermined length W,
The installation interval (D) is preferably set so as to satisfy the relationship represented by the following Expression 11.

  According to this, by setting the installation interval (D) between the light projecting unit and the light receiving unit so as to satisfy Equation 11 in consideration of the inclination of the light projecting unit and the size of the radiation angle, the light is emitted from the light projecting unit. Even when light located at the outermost part of the light is reflected by a predetermined length of water droplets attached to the outer surface of the cover, the light can be controlled to be reflected at a position where it cannot be received by the light receiving unit. As a result, a simple technique based on the conditions of the light projecting unit and the size of water droplets on the outer surface of the cover can be provided as a design for preventing erroneous detection of the cover.

In the invention of claim 7, the installation interval in claim 1 is D, the predetermined light receiving angle is β, and the inclination angle of the axis (36) of the light receiving portion with respect to the perpendicular direction of the cover inner surface (7a) is θ2. The distance from the tip part (20a, 22a) of the light projecting part to the cover is g1, the distance from the tip part (30a) of the light receiving part to the cover is g2, the refractive index of air is n1, When the refractive index is n2, the thickness dimension of the cover is t, and the attached surface length of water drops or the like attached to the cover is a predetermined length W,
The installation interval (D) is preferably set so as to satisfy the relationship represented by the following Expression 12.

  According to this, the light emitted from the light projecting unit is set by setting the installation interval (D) between the light projecting unit and the light receiving unit so as to satisfy Expression 12 in consideration of the inclination of the light receiving unit and the size of the light receiving angle. Of these, even when the light located at the outermost part is reflected by a predetermined length of water droplets attached to the outer surface of the cover, the light can be controlled to be reflected at a position where it cannot be received by the light receiving unit. As a result, a simple method based on the conditions of the light receiving unit and the size of water droplets on the outer surface of the cover can be provided as a design for preventing erroneous detection of the cover.

  In the invention according to claim 8, the automatic water faucet device further includes a light emitting element (102) that outputs light to the light projecting unit, and a light projecting optical fiber that guides the light output from the light emitting element to the light projecting unit ( 4), a light receiving element (103) to which the light received by the light receiving unit is input, and a light receiving optical fiber (5) for guiding the light received by the light receiving unit to the light receiving element.

  An optical fiber has a wide emission angle and light reception angle, and thus tends to detect a cover easily. Therefore, according to the present invention, by setting the installation interval between the light projecting unit and the light receiving unit to the above setting, a more remarkable effect of preventing erroneous cover detection can be obtained.

  In addition, the code | symbol in the bracket | parenthesis of each said means is an example which shows a corresponding relationship with the specific means of embodiment mentioned later.

  A plurality of modes for carrying out the present invention will be described below with reference to the drawings. In each embodiment, parts corresponding to the matters described in the preceding embodiment may be denoted by the same reference numerals, and redundant description may be omitted. When only a part of the configuration is described in each mode, the other modes described above can be applied to the other parts of the configuration. Not only combinations of parts that clearly show that combinations are possible in each embodiment, but also combinations of the embodiments even if they are not specified unless there is a problem with the combination. Is also possible.

(First embodiment)
1st Embodiment which is one Embodiment of this invention is described according to FIGS. FIG. 1 is a schematic diagram showing a schematic configuration of an automatic faucet device according to the present embodiment. FIG. 2 is a block diagram showing the configuration of the control device 100. FIG. 3 is a partial cross-sectional view showing configurations of the light projecting assembly 2 and the light receiving assembly 3.

  This automatic faucet device automatically detects when there is an object to be cleaned, such as a human hand, in the detection target area for the space below the discharge part where tap water is discharged. This is a device for home use or business use in which water is discharged and stopped, and is used, for example, as a hand-washing plug in a toilet, a kitchen or the like.

  This automatic faucet device detects an object to be cleaned using a light projecting unit that emits light and a light receiving unit that receives reflected light of the emitted light. The light projecting part and the light receiving part may be splashed with water, attached with detergent, or other dirt due to hand-washing operation. Therefore, in order to ensure detection performance, it is protected with a cover that covers the light projecting part There is a need. The cover 7 is provided in front of the light projecting unit and the light receiving unit on the detection target area side so as to cover the front of the light projecting unit and the light receiving unit. And the light receiving part is protected. The material of the cover 7 is made of a transparent resin, glass or the like that can transmit light. Moreover, the cover 7 may be provided with the window part which permeate | transmits light.

  The light radiated from the light projecting unit is normally radiated to the detection target area through the cover 7. When a human hand or the like is present in the light receiving area, the reflected light reflected by the light passes through the light receiving area and enters the light receiving unit to be received. On the other hand, the light emitted from the light projecting part may be reflected by the cover and received by the light receiving part due to the assembly error or manufacturing error of each part. In addition, this phenomenon may occur due to the adhering matter attached to the cover.

  In view of this, the automatic faucet device includes a cover 7 having light permeability that protects the light projecting unit and the light receiving unit from dirt and the like, and accurately detects an object to be cleaned such as a human hand and is reflected by the cover. It is provided that the light to be detected is detected and the cover is prevented from being erroneously detected as the object to be cleaned.

  As shown in FIG. 1, the automatic faucet device includes a main body case 10 in which a control device 100 is built, a faucet case 1 having a discharge portion 6 (discharge port) through which tap water is discharged, and both cases. And an optical carrier line and a water supply hose 14 disposed therebetween. A water supply pipe 11 through which tap water flows passes through the main body case 10, and the water supply pipe 11 is connected on the suction side of a water supply hose 14 connected to the discharge unit 6.

  Further, an electromagnetic valve 12 and a generator 13 are provided inside the main body case 10. The electromagnetic valve 12 is a valve body that is provided in the middle of the water supply pipe 11 and opens and closes the passage of the water supply pipe 11. The generator 13 is provided in the middle of the water supply pipe 11 and closer to the discharge unit 6 (downstream side) than the electromagnetic valve 12. The generator 13 generates electricity by rotating a built-in water wheel by a water flow in the water supply pipe 11.

  The generator 13 includes a magnet that is a rotor coupled to a rotating shaft of a water turbine, and a stator coil that is disposed radially outward of the rotating shaft with respect to the magnet, and the electromagnetic valve 12 is in an open state. When a water flow is formed, an induced electromotive force is generated in the stator coil by the rotation of the magnet accompanying the rotation of the water wheel.

  As shown in FIG. 2, the control device 100 includes various electronic components such as a microcomputer 101, a light emitting element 102, a light receiving element 103, and a capacitor 112, and controls the overall operation of the automatic water faucet device. The microcomputer 101 executes various calculations using signals from the input side of the light receiving element 103 and the like, and has a built-in ROM and RAM as storage means and stores a preset control program and an updatable control program. Have.

  The microcomputer 101 sends a signal for causing the light emitting element 102 to emit light via the drive circuit 105. The received light signal of the reflected light from the sensing object output from the light receiving element 103 is amplified by the amplifier circuit 106, held by the sample hold unit 108, converted by the A / D converter 109, and input to the microcomputer 101. The The microcomputer 101 executes various calculations using the signals input in this way, and outputs a signal based on the calculation results to the electromagnetic valve 12 by the drive circuit 110 to control the opening and closing thereof.

  The power storage device 112 is power storage means in the automatic water faucet device, and is a storage battery composed of, for example, a secondary battery, and stores the power generated by the generator 13. The electric power generated by the generator 13 covers the electric power required for the automatic water faucet apparatus such as the microcomputer 101 and the light emitting process of the light emitting element 102. The power generated by the generator 13 is rectified by the rectifier 113, stored in the capacitor 112, and further supplied to the power source 111.

  The light emitting element 102 is a light source for detecting an object, and is connected to a light projecting portion of a light projecting assembly 2 disposed in the faucet case 1 by a light projecting optical fiber 4 which is a light carrying line. The light emitting element 102 is a light emitting diode (LED) that emits visible light toward the light projecting optical fiber 4. The light output from the light emitting element 102 is guided to the light projecting portion of the light projecting assembly 2 by the light projecting optical fiber 4. The visible light has a wavelength of, for example, 600 to 700 nm, more preferably about 650 nm. When such visible light is used, the light emission efficiency of the light emitting diode is improved, and the transmittance of the optical fiber made of plastic is excellent.

  The light receiving element 103 is connected to a light receiving portion of the light receiving assembly 3 disposed in the faucet case 1 by a light receiving optical fiber 5 which is a light carrying line. The light receiving element 103 is formed of a photodiode or the like, receives light guided by the light receiving optical fiber 5, and outputs an electric signal corresponding to the amount of received light. As the light receiving element 103, a light receiving element having high sensitivity to the wavelength of light emitted from the light emitting element 102 is used.

  The faucet case 1 is attached so as to protrude from a wall 52 where the automatic faucet device is installed, and a substantially bowl-shaped sink 50 is provided below the faucet case 1. And at the front end side of the faucet case 1, the discharge part 6, the light projection assembly 2, and the light reception assembly 3 are arrange | positioned so that the detection object area below may be faced. The optical fibers 4 and 5 and the water supply hose 14 are arranged through a hole 53 formed in the wall 52 so as to connect between the faucet case 1 and the main body case 10. In addition, the light projecting optical fiber 4 and the light receiving optical fiber 5 are preferably made of plastic that is more flexible than quartz glass and strong against bending.

  As shown in FIG. 3, the light projecting assembly 2 is provided so that the light projecting end portion 22 of the light projecting optical fiber 4 is in close contact with the lens 20 that is a condensing means, and the periphery of the lens 20 is held by a holder 23. It is configured in this way. When the light condensing means is provided as in the present embodiment, the lens 20 is the light projecting unit of the present invention that emits light toward the detection target area above the sink 50. On the contrary, when the light condensing means is not provided, the light projecting end portion 22 is the light projecting portion of the present invention.

  The holder 23 fixes the lens 20 by press-fitting, and fixes the light projecting end portion 22 and the covering portion 25 of the light projecting optical fiber 4 via an adhesive 24, and the holder 23 itself is attached to the faucet case 1. ing. With this structure, the light projecting optical fiber 4 can be firmly fixed without being damaged. Further, the covering portion 25 is not provided on the lens 20 side portion of the light projecting end portion 22. This is to prevent the covering portion 25 from extending due to thermal expansion and entering between the lens 20 and the fiber tip, and to improve the adhesiveness of the adhesive 24. Here, the adhesive is desirably black, which has a high light-absorbing effect, so that light condensing and non-dispersion can be expected, and generation of stray light can be prevented. Further, an O-ring 21 is externally fitted near the tip of the light projecting end portion 22 and the O-ring 21 is held by a holder 23 from the outside to ensure a sealing property so that the adhesive 24 does not flow on the lens surface. ing.

  The light receiving assembly 3 is configured so that the holder 31 holds the periphery of the light receiving end 30 of the light receiving optical fiber 5. The holder 31 fixes the light receiving end 30 and the covering portion 33 of the light receiving optical fiber 5 via an adhesive 32, and the holder 31 itself is attached to the faucet case 1. Again, the adhesive is preferably black for the reasons described above. With this structure, the light receiving optical fiber 5 can be firmly fixed without being damaged.

  Since the light receiving assembly 3 does not include a light collecting means such as a lens, the light receiving assembly 3 receives reflected light at a light receiving angle of the optical fiber itself. Therefore, the target area where the light receiving assembly 3 can receive the reflected light reflected by the sensing object is wide. For example, when a plastic optical fiber is used, incident light having an apex angle (light receiving angle) of about π / 3 radians (60 °), that is, a cone angle of about π / 6 radians (30 °) can be received. it can. When the light condensing means is not provided as in the present embodiment, the light receiving end 30 is a light receiving unit of the present invention that receives light reflected by an object in the detection target area.

  In the light receiving assembly 3, the axes 26 and 36 are arranged at a predetermined angle (unit: radians) so that the tip ends of the light receiving assembly 3 are close to each other. In FIG. 3, as an example, the light emitting unit is installed with the axis 26 inclined by θ1 (unit: radians) with respect to the vertical direction. Further, the axes 26 and 36 are in a relationship such that they intersect in a detectable area formed toward the sink 50. The light projecting unit and the light receiving unit are arranged such that a distance D is formed between the light receiving unit side tip part 20a of the lens and the light projecting unit side tip part 30a of the light receiving unit. In other words, the installation interval between the tip portion that radiates light from the light projecting portion and is closest to the light receiving portion and the tip portion that is the portion that receives reflected light from the light receiving portion and is closest to the light projecting portion is predetermined. Distance D.

  The axis 26 of the light projecting unit coincides with the axis (optical axis) of the light projected toward the sink 50 below, and the apex angle α (unit is radians, with the cone angle of the cone angle). A conical light projecting area 40 (an area indicated by a hatched portion in FIG. 1) having a double angle is formed. The light projecting area 40 is an area included in a cone formed so as to widen toward the sink 50 at a cone angle α / 2, and is also a detection area that occupies a part of the light receiving area 41. The apex angle α is an angle in a range in which light emitted from the tip of the light projecting optical fiber 4 diffuses around the optical axis, and is also referred to as a radiation angle α. The cone angle α / 2 which is a half of the apex angle is obtained by changing the radiation angle π / 3 radians (60 °) of the optical fiber 4 for projection by the lens 20 to, for example, π / 36 to π / 9 radians (5 ° to 20 °). The angle is limited to the range.

  The light receiving assembly 3 sinks a conical light receiving area 41 having an apex angle β (the unit is radians as in α and twice the cone angle) around the axis 36 direction of the light receiving portion. It forms toward 50. The angle β is larger than the angle α, and is approximately π / 3 radians (60 °) because a plastic optical fiber is used in this embodiment. The light projecting area 40 and the light receiving area 41 intersect with each other in the detection target area to form a common area. The light receiving part side tip part 20a of the lens and the light projecting part side tip part 30a of the light receiving part The distance D is set to a distance that forms the shared area.

  The light receiving area 41 receives only the light reflected by the object existing in the area shared with the light projecting area 40. In the example shown in FIG. 1, the light receiving area 41 has a size that includes substantially the entire light projecting area 40, and other areas other than the light projecting area 40 are included in the area. Then, since no light is projected, no reflected light is generated, and the light receiving assembly 3 receives only the reflected light from the light rays in the light projecting area 40.

  The light receiving assembly 3 collects and receives only the light reflected in the light receiving area 41 that overlaps the light projecting area 40. The amount of electricity of the received light reception signal (the output value of the amount of light received) is guided from the light receiving assembly 3 to the light receiving optical fiber 5 and input to the light receiving element 103.

  Next, when the light emitted from the light projecting unit is reflected by the cover 7 provided so as to cover the front side of the detection target area of the light projecting unit and the light receiving unit, the light receiving unit receives the reflected light and When light is not received, each state in which light travels will be described with reference to FIGS. First, the case where the radiation angle α is set larger than the light receiving angle β will be described with reference to FIGS. 4 and 5 as an example. Each figure of FIG. 4 is a schematic diagram for explaining the progress of light when radiated light is reflected by the cover when the light projecting part and the light receiving part are not inclined and are installed in the perpendicular direction Z of the inner surface 7a of the cover. FIG.

  FIG. 4A shows an installation interval D (hereinafter also referred to as an installation interval between the light projecting unit and the light receiving unit) D between the light receiving unit side front end region 22a of the light projecting unit and the light projecting unit side front end region 30a of the light receiving unit. This is a case where the light projecting area 40 and the light receiving area 41 do not intersect on the inner surface 7a of the cover and do not form a common area. In this state, there is a distance D1 between the light receiving part-side tip part 22a of the light projecting part and the point 22R returning after the light emitted from the outermost part of the light projecting part is reflected by the inner surface 7a of the cover. Since the installation interval D between the light projecting unit and the light receiving unit is smaller (D1 <D), the radiated light is not received by the light receiving end 30.

  In FIG. 4B, the installation distance D between the light projecting part and the light receiving part is smaller than the distance D1, and the light projecting area 40 and the light receiving area 41 do not intersect on the inner surface 7a of the cover to form a common area. This is the case. Further, at this time, the installation interval D between the light projecting unit and the light receiving unit is a point 30R where the light projecting unit side tip portion 30a of the light receiving unit and the outermost site of the light receiving area 41 are reflected by the inner surface 7a of the cover and returned. It is larger than the distance D2 between (D2 <D <D1). In this state, the emitted light is incident on the light receiving end 30, but is not received by the light receiving end 30.

  This is because the light receiving unit is configured not to receive (receive no light) the optical signal even if light enters from outside the light receiving area 41 formed by itself. In other words, the light receiving unit does not receive the optical signal of the light reflected outside the light receiving area 41. In other words, the light receiving portion is configured to receive only light incident at an angle smaller than half the light receiving angle (β / 2) with respect to the perpendicular direction Z of the inner surface 7a of the cover. It is.

  In FIG. 4C, the installation distance D between the light projecting part and the light receiving part is smaller than the distance D1 (D <D1), and the light projecting area 40 and the light receiving area 41 intersect and share on the inner surface 7a of the cover. This is a case where the area 42 is formed. In this state, the light emitted from the outermost part of the light projecting unit does not enter the light receiving end 30 and is not incident on the light receiving end 30, but part of the reflected light reflected by the common area 42 is a part of the light receiving end. Since the light is incident on the light receiving portion 30, the light receiving portion receives the reflected light from the cover 7.

  Each figure of FIG. 5 shows the progress of light when the radiated light is reflected by the cover 7 when the light projecting part and the light receiving part are installed inclined with respect to the perpendicular direction Z of the inner surface 7a of the cover. It is a schematic diagram to explain. FIG. 5A shows a case where the installation distance D between the light projecting part and the light receiving part is sufficiently large, and the light projecting area 40 and the light receiving area 41 do not intersect on the inner surface 7a of the cover and do not form a shared area. is there. In this state, there is a distance D1 between the light receiving part-side tip part 22a of the light projecting part and the point 22R returning after the light emitted from the outermost part of the light projecting part is reflected by the inner surface 7a of the cover. Since the distance between the light projecting part and the light receiving part is smaller than D (D1 <D), the emitted light is not received by the light receiving end part 30.

  In FIG. 5B, the installation distance D between the light projecting part and the light receiving part is smaller than the distance D1, and the light projecting area 40 and the light receiving area 41 do not intersect on the inner surface 7a of the cover to form a common area. This is the case. Further, at this time, the installation interval D between the light projecting unit and the light receiving unit is a point 30R where the light projecting unit side tip portion 30a of the light receiving unit and the outermost site of the light receiving area 41 are reflected by the inner surface 7a of the cover and returned. It is larger than the distance D2 between (D2 <D <D1). In this state, the radiated light is incident on the light receiving end 30, but is not incident on the light receiving end 30 because it is light incident from outside the light receiving area 41.

  In FIG. 5C, the installation distance D between the light projecting part and the light receiving part is smaller than the distance D1 (D <D1), and the light projecting area 40 and the light receiving area 41 intersect and share on the inner surface 7a of the cover. This is a case where the area 42 is formed. In this state, a part of the radiated light reflected by the shared area 42 enters the light receiving end 30 and receives the light, so that the light receiving unit receives the reflected light from the cover 7.

  Next, the case where the light receiving angle β is set larger than the radiation angle α will be described with reference to FIGS. 6 and 7 as an example. FIGS. 6A and 6B are schematic diagrams for explaining the progress of light when radiated light is reflected by the cover when the light projecting unit and the light receiving unit are not inclined and are installed in the perpendicular direction Z of the inner surface 7a of the cover. FIG. Each figure of FIG. 7 shows the light traveling state when the radiated light is reflected by the cover 7 when the light projecting part and the light receiving part are installed inclined with respect to the perpendicular direction Z of the inner surface 7a of the cover. It is a schematic diagram to explain.

  In FIG. 6A, the installation distance D between the light projecting part and the light receiving part (the distance between 22a and 30a in FIG. 6A) is sufficiently large, and the light projecting area 40 and the light receiving area 41 are the inner surface 7a of the cover. This is a case where no common area is formed without crossing above. In this state, there is a distance D1 between the light receiving part-side tip part 22a of the light projecting part and the point 22R returning after the light emitted from the outermost part of the light projecting part is reflected by the inner surface 7a of the cover. Since the installation interval D between the light projecting unit and the light receiving unit is smaller (D1 <D), the radiated light is not received by the light receiving end 30.

  Although not shown in particular, even if the light projecting area 40 and the light receiving area 41 form a common area, there may be a positional relationship in which the emitted light is not received by the light receiving end 30. In this case, the light projecting unit and the light receiving unit are closer to each other than the state shown in FIG. The light projecting area 40 and the light receiving area 41 intersect on the inner surface 7a of the cover to form a shared area 42, but the distance D1 is smaller than the installation interval D between the light projecting part and the light receiving part (D1 < D) Therefore, the emitted light is not received by the light receiving end 30.

  In FIG. 6B, the installation distance D between the light projecting part and the light receiving part is smaller than the distance D1, and the light projecting area 40 and the light receiving area 41 intersect on the inner surface 7a of the cover to form a shared area 42. This is the case. In this state, the light emitted from the light projecting unit is reflected by the shared area 42 and incident on the light receiving end 30 to be received, so that the light receiving unit receives the reflected light from the cover 7. become.

  In FIG. 7A, the installation distance D between the light projecting part and the light receiving part (the distance between 22a and 30a in FIG. 7A) is sufficiently large, and the light projecting area 40 and the light receiving area 41 are the inner surface 7a of the cover. This is a case where no common area is formed without crossing above. In this state, there is a distance D1 between the light receiving part-side tip part 22a of the light projecting part and the point 22R returning after the light emitted from the outermost part of the light projecting part is reflected by the inner surface 7a of the cover. Since the installation interval D between the light projecting unit and the light receiving unit is smaller (D1 <D), the radiated light is not received by the light receiving end 30.

  Although not shown in particular, even if the light projecting area 40 and the light receiving area 41 form a common area, there may be a positional relationship in which the emitted light is not received by the light receiving end 30. In this case, the light projecting unit and the light receiving unit come closer to each other than the state shown in FIG. The light projecting area 40 and the light receiving area 41 intersect on the inner surface 7a of the cover to form a shared area 42, but the distance D1 is smaller than the installation interval D between the light projecting part and the light receiving part (D1 < D) Therefore, the emitted light is not received by the light receiving end 30.

  In FIG. 7B, the installation distance D between the light projecting part and the light receiving part is smaller than the distance D1, and the light projecting area 40 and the light receiving area 41 intersect on the inner surface 7a of the cover to form a shared area 42. This is the case. In this state, the light emitted from the light projecting unit is reflected by the shared area 42 and incident on the light receiving end 30 to be received, so that the light receiving unit receives the reflected light from the cover 7. become.

  Next, setting conditions for installing the light projecting assembly 2 and the light receiving assembly 3 in the automatic faucet device will be described with reference to FIGS. FIG. 8 is a schematic diagram for explaining the concept of setting the installation interval D between the light projecting unit and the light receiving unit based on the emission angle α and the inclination θ1 of the light projecting unit. FIG. 9 is a schematic diagram for explaining the installation interval D between the light projecting unit and the light receiving unit based on the light receiving angle β and the inclination θ2 of the light receiving unit.

  The setting concept of the installation interval D between the light projecting unit and the light receiving unit shown in FIGS. 8 and 9 assumes that the light emitted from the light projecting end 22 is reflected by the inner surface 7a of the cover and returns. is doing. The installation interval D shown in the figure is the upper limit distance D when the reflected light from the inner surface 7a of the cover is received by the light receiving unit. For this reason, in the setting concept based on the emission angle α and the inclination θ1 of the light projecting unit in FIG. 8, the installation interval D of the automatic faucet device is calculated from the value obtained by calculating the right side of the following Expression 13. May be set to a larger value.

  That is, the installation interval D is set so as to satisfy the relationship represented by the following Expression 13, and the light projecting unit and the light receiving unit are arranged in a positional relationship according to the relationship.

  In Expression 13, α is a predetermined radiation angle, θ1 is the inclination angle of the axis 26 of the light projecting unit with respect to the perpendicular direction Z of the inner surface 7a of the cover, and g1 is from the light receiving unit side tip region 22a of the light projecting unit. This is the distance to the cover 7, and g <b> 2 is the distance from the light projecting part side tip portion 30 a of the light receiving part to the cover 7.

  According to the simple setting method based on each condition of the light projecting unit obtained by Expression 13, even when the light located at the outermost part of the light emitted from the light projecting unit is reflected by the cover 7, the light receiving unit. It is possible to obtain an optical system that reflects the reflected light to a position where it cannot receive the reflected light. Further, if the installation interval D is set so as to satisfy Expression 13, it is not necessary to separately provide a light shielding plate for shielding light between the light projecting unit and the light receiving unit, so that the number of parts can be reduced.

  Next, in the setting concept based on the light receiving angle β and the inclination θ2 of the light receiving unit in FIG. 9, the installation interval D of the automatic water faucet device is larger than the value obtained by calculating the right side of the following Expression 14. A large value may be set.

  That is, the installation interval D is set so as to satisfy the relationship represented by the following Expression 14, and the light projecting unit and the light receiving unit are arranged in a positional relationship according to the relationship.

  In Expression 14, β is a predetermined light receiving angle, θ2 is an inclination angle of the light receiving portion axis 36 with respect to the perpendicular direction Z of the inner surface 7a of the cover, and g1 and g2 are the same distances as in FIG.

  Even with a simple setting method based on each condition of the light receiving part obtained by the equation 14, the light receiving part is reflected even when light located at the outermost part of the light emitted from the light projecting part is reflected by the cover 7. An optical system that reflects light at a position or angle where light cannot be received can be obtained. Further, if the installation interval D is set so as to satisfy Expression 14, it is not necessary to separately provide a light shielding plate for shielding light between the light projecting unit and the light receiving unit, so that the number of parts can be reduced.

  The effects brought about by the automatic faucet device according to this embodiment will be described below. In this automatic water faucet device, the light emitting part is a part that emits light and is the light receiving part side tip part 22a of the light projecting part closest to the light receiving part, and the part that receives the reflected light of the light receiving part. The installation interval D between the light-receiving unit closest to the light unit and the light-projecting-unit-side tip portion 30a is set to a distance that forms a shared area when the light-projecting area 40 and the light-receiving area 41 intersect in the detection target area. At the same time, even when light traveling through the outermost part of the light emitted from the light projecting part is reflected by the cover 7, the distance is set such that the emitted light is not received by the light receiving part.

  According to this configuration, even if the light emitted from the light projecting unit is reflected by the cover 7, the light receiving unit does not receive the reflected light, and thus erroneous detection of the cover 7 for protecting the light projecting unit and the light receiving unit is prevented. Can be prevented. Further, it is a precondition that the installation interval D between the light projecting unit and the light receiving unit is set to a distance at which the light projecting area 40 and the light receiving area 41 intersect to form a common area 42 in the detection target area. Satisfying this precondition is also the upper limit condition of the installation interval D. In addition, when the light traveling through the outermost part of the radiated light is reflected by the cover 7, the distance at which the radiated light is not received by the light receiving unit Is also a lower limit condition of the installation interval D. Accordingly, the installation distance D between the light projecting unit and the light receiving unit can be set to a distance that is not too close and not too close, so that both effects of preventing erroneous detection of the cover 7 and miniaturization of the automatic water faucet device can be obtained. .

  Moreover, the arrangement | positioning of a light projection part and a light-receiving part is determined by selecting D with the smaller calculated value of a right side among the said Formula 13 and Formula 14, and setting the said installation space | interval D based on this. Is preferred. According to this configuration, the lower limit condition of the installation interval D can be further reduced, and the apparatus can be further miniaturized.

(Second Embodiment)
2nd Embodiment is another setting concept used in order to set the installation space | interval D of a light projection part and a light-receiving part. In the present embodiment, the concept of setting the installation interval D in consideration of the fact that there are deposits on the cover 7 and the radiated light is reflected by the deposits will be described with reference to FIGS. 10 and 11. FIG. 10 is a schematic diagram for explaining the concept of setting the installation interval D between the light projecting unit and the light receiving unit based on the radiation angle α and the inclination θ1 of the light projecting unit. FIG. 11 is a schematic diagram illustrating a setting concept of the installation interval D between the light projecting unit and the light receiving unit based on the light receiving angle β and the inclination θ2 of the light receiving unit.

  The setting concept of the installation distance D between the light projecting unit and the light receiving unit shown in FIGS. 10 and 11 is that the light emitted from the light projecting end 22 is refracted from the inner surface 7a of the cover, and the outer surface of the cover It is assumed that the light is reflected by an adhering matter such as dirt adhering to 7b, and is further refracted and returned from the inside of the cover 7 by the air layer on the inner surface 7a side. And the said installation space | interval D shown by the figure is the upper limit distance D in case the reflected light in an attachment is received by a light-receiving part. For this reason, in the setting concept based on the emission angle α and the inclination θ1 of the light projecting unit in FIG. 10, the installation interval D of the automatic faucet device is calculated from the value obtained by calculating the right side of the following Expression 15. May be set to a larger value.

  That is, the installation interval D is set so as to satisfy the relationship expressed by the following Expression 15, and the light projecting unit and the light receiving unit are arranged in a positional relationship according to the relationship.

  In Expression 15, α is a predetermined radiation angle, θ1 is an inclination angle of the axis 26 of the light projecting unit with respect to the perpendicular direction Z of the inner surface 7a of the cover, and g1 is a light receiving unit side tip portion 22a of the light projecting unit. Is a distance from the light projecting portion side tip portion 30a of the light receiving portion to the cover 7. Furthermore, n1 is the refractive index of air, n2 is the refractive index of the cover, and t is the thickness dimension of the cover.

  As shown in FIG. 10, the equation on the right side of Equation 15 is the sum of g1 · tan (θ1 + α / 2), X1, X1, g2 · tan (θ1 + α / 2). Below, the calculation method of X1 is demonstrated.

First, according to the law of refraction,
n1 · cosA1 = n2 · cosB1 (Equation 15a) holds,
From Expression 15a, B1 = cos ⁻¹ {(n1 / n2) · cosA1} (Expression 15b).

A1 = (θ1 + α / 2) + π / 2 (Equation 15c)
Since X1 = t · tan (B1−π / 2) (Equation 15d),
Substituting Equation 15b and Equation 15c into Equation 15d,
X1
= T · tan [cos ⁻¹ {(n1 / n2) · cos (θ1 + α / 2 + π / 2)} − π / 2]. When (g1 + g2) · tan (θ1 + α / 2) is added to the expression obtained by doubling X1, the expression on the right side of Expression 15 is obtained.

  As described above, according to the simple setting method based on the conditions of the light projecting unit obtained by Expression 15, when dirt or the like is attached to the cover 7, the light emitted from the light projecting unit Even if light located at the outermost part is refracted in the cover 7 and reflected by the deposit on the cover 7, an optical system is obtained in which the light receiving part reflects the reflected light to a position where it cannot receive the reflected light. Can be provided. Further, if the installation interval D is set so as to satisfy Expression 15, it is not necessary to separately provide a light shielding plate between the light projecting unit and the light receiving unit, so that the number of parts can be reduced.

  Next, in the setting concept based on the light receiving angle β and the inclination θ2 of the light receiving unit in FIG. 11, the installation interval D of the automatic faucet device is more than the value obtained by calculating the right side of the following Expression 16. A large value may be set.

  That is, the installation interval D is set so as to satisfy the relationship expressed by the following Expression 16, and the light projecting unit and the light receiving unit are arranged in a positional relationship according to the relationship.

  In Expression 16, β is a predetermined light receiving angle, and θ2 is an inclination angle of the axis 36 of the light receiving portion with respect to the perpendicular direction Z of the inner surface 7a of the cover.

  As shown in FIG. 11, the equation on the right side of Equation 16 is the sum of g1 · tan (θ2 + β / 2), X2, X2, g2 · tan (θ2 + β / 2). Below, the calculation method of X2 is demonstrated.

First, according to the law of refraction,
n1 · cosA2 = n2 · cosB2 (Equation 16a) holds,
From Expression 16a, B2 = cos ⁻¹ {(n1 / n2) · cosA2} (Expression 16b).

A2 = (θ2 + β / 2) + π / 2 (Equation 16c)
Since X2 = t · tan (B2−π / 2) (Expression 16d),
When Expression 16b and Expression 16c are substituted into Expression 16d,
X2
= T · tan [cos ⁻¹ {(n1 / n2) · cos (θ2 + β / 2 + π / 2)} − π / 2]. When (g1 + g2) · tan (θ2 + β / 2) is added to the expression obtained by doubling X2, the expression on the right side of Expression 16 is obtained.

  As described above, according to the simple setting method based on each condition of the light receiving part obtained by Expression 16, when dirt or the like is attached to the cover 7, the light emitted from the light projecting part is the maximum. An apparatus for preventing an erroneous detection by obtaining an optical system in which a light receiving unit reflects light at a position or an angle where reflected light cannot be received even when light located at an outer portion is refracted in the cover 7 and reflected by an object attached to the cover 7 Can provide. Further, if the installation interval D is set so as to satisfy Expression 16, it is not necessary to separately provide a light shielding plate between the light projecting unit and the light receiving unit, so that the number of parts can be reduced.

(Third embodiment)
3rd Embodiment is another setting concept used in order to set the installation space | interval D of a light projection part and a light-receiving part. In the present embodiment, the concept of setting the installation interval D in consideration of the fact that water droplets or the like are attached to the outer surface 7b of the cover and the light is reflected through the water droplets will be described with reference to FIGS. To do. FIG. 12 is a schematic diagram for explaining the concept of setting the installation interval D between the light projecting unit and the light receiving unit based on the emission angle α and the inclination θ1 of the light projecting unit. FIG. 13 is a schematic diagram illustrating a setting concept of the installation interval D between the light projecting unit and the light receiving unit based on the light receiving angle β and the inclination θ2 of the light receiving unit.

  The setting concept of the installation interval D between the light projecting unit and the light receiving unit shown in FIGS. 12 and 13 is that the light emitted from the light projecting end 22 is refracted from the inner surface 7a of the cover, and the outer surface of the cover It is assumed that the light is reflected in a deposit such as water droplets adhering to 7b, and is further refracted and returned from the inside of the cover 7 by the air layer on the inner surface 7a side.

  In the case of this assumption, it is necessary to consider the length of the adhesion surface such as water droplets. In this embodiment, the adhering surface length of the water droplet or the like is a predetermined length W. Since the predetermined length W is a value that varies depending on the shape, installation posture, and material of the cover 7, it is a value that is determined in consideration of empirical rules based on experiments and the situation in which the automatic faucet device is used. For example, it is determined to be 10 mm or less.

  And the said installation space | interval D shown by the figure is the upper limit distance D in case the reflected light in an attachment is received by a light-receiving part. For this reason, in the setting concept based on the emission angle α and the inclination θ1 of the light projecting unit in FIG. 12, the installation interval D of the automatic faucet device is calculated from the value obtained by calculating the right side of the following Expression 17. May be set to a larger value.

  That is, the installation interval D is set so as to satisfy the relationship represented by the following Expression 17, and the light projecting unit and the light receiving unit are arranged in a positional relationship according to the relationship. Further, the right side of Expression 17 below is an expression obtained by adding a predetermined length W to the right side of Expression 15 in the second embodiment.

  As described above, according to the simple setting method based on the conditions of the light projecting unit obtained by Expression 17, when water droplets or the like are attached to the cover 7, the light emitted from the light projecting unit Even when light located at the outermost part is refracted in the cover 7 and reflected inside a water droplet or the like adhering to the outer surface 7b of the cover, an optical system that reflects the reflected light to a position where the reflected light cannot be received is obtained. Therefore, it is possible to provide a device that prevents erroneous detection. Further, if the installation interval D is set so as to satisfy Expression 17, it is not necessary to separately provide a light shielding plate between the light projecting unit and the light receiving unit, so that the number of parts can be reduced.

  Next, in the setting concept based on the light receiving angle β and the inclination θ2 of the light receiving unit in FIG. 13, the installation interval D of the automatic faucet device is more than the value obtained by calculating the right side of the following Equation 18. A large value may be set.

  That is, the installation interval D is set so as to satisfy the relationship expressed by the following equation 18, and the light projecting unit and the light receiving unit are arranged in a positional relationship according to the relationship. Moreover, the right side of the following formula 18 is a formula in which a predetermined length W is added to the right side of the formula 16 in the second embodiment in consideration of the attached surface length of a water droplet or the like.

  As described above, according to the simple setting method based on each condition of the light receiving unit obtained by Expression 18, when water droplets or the like are attached to the cover 7, the light emitted from the light projecting unit is the maximum. An optical system that reflects light at a position or angle at which the light receiving unit cannot receive reflected light even when light located at the outer portion is refracted in the cover 7 and reflected inside a water droplet or the like attached to the outer surface 7b of the cover. It is possible to provide a device that is obtained and prevents erroneous detection. Further, if the installation interval D is set so as to satisfy Expression 18, it is not necessary to separately provide a light shielding plate between the light projecting unit and the light receiving unit, so that the number of parts can be reduced.

  Moreover, the arrangement | positioning of a light projection part and a light-receiving part is determined by selecting D with the smaller calculated value of a right side among the said Formula 17 and Formula 18, and setting the said installation space | interval D based on this. Is preferred. According to this configuration, the lower limit condition of the installation interval D can be further reduced, and the apparatus can be further miniaturized.

It is the mimetic diagram showing the schematic structure of the automatic faucet device concerning a 1st embodiment. 2 is a block diagram illustrating a configuration of a control device 100. FIG. FIG. 3 is a partial cross-sectional view showing configurations of a light projecting assembly 2 and a light receiving assembly 3. (A)-(c) are the progress states of the light when the emitted light is reflected by the cover when the emission angle is larger than the reception angle and the light projecting part and the light receiving part are installed in the direction perpendicular to the inner surface of the cover. FIG. (A) to (c) are the cases where the emitted light is reflected by the cover when the emission angle is larger than the reception angle and the light projecting part and the light reception part are installed inclined with respect to the normal direction of the inner surface of the cover. It is a schematic diagram explaining the advancing state of light. (A) and (b) show the progress of light when the radiated light is reflected by the cover when the light receiving angle is larger than the radiation angle and the light projecting part and the light receiving part are installed in the direction perpendicular to the inner surface of the cover. FIG. (A) and (b) are the results when the radiated light is reflected by the cover when the light receiving angle is larger than the radiation angle and the light projecting part and the light receiving part are installed inclined with respect to the normal direction of the inner surface of the cover. It is a schematic diagram explaining the advancing state of light. It is a schematic diagram explaining the setting concept of the installation interval D between the light projecting unit and the light receiving unit based on the radiation angle α and the inclination θ1 of the light projecting unit in the first embodiment. It is a schematic diagram explaining the setting concept of the installation space | interval D of the light projection part and light reception part based on the light reception angle (beta) and inclination (theta) 2 of a light reception part in 1st Embodiment. It is a schematic diagram explaining the setting concept of the installation space | interval D of a light projection part and a light-receiving part based on radiation angle (alpha) and inclination (theta) 1 of a light projection part in 2nd Embodiment. It is a schematic diagram explaining the setting concept of the installation space | interval D of a light projection part and a light-receiving part based on the light reception angle (beta) and inclination (theta) 2 of a light-receiving part in 2nd Embodiment. It is a schematic diagram explaining the setting concept of the installation space | interval D of the light projection part and light reception part based on radiation angle (alpha) and inclination (theta) 1 of a light projection part in 3rd Embodiment. It is a schematic diagram explaining the setting concept of the installation space | interval D of the light projection part and light reception part based on the light reception angle (beta) and inclination (theta) 2 of a light reception part in 3rd Embodiment.

Explanation of symbols

4 ... Optical fiber for light emission 5 ... Optical fiber for light reception 7 ... Cover 7a ... Inner surface of cover (inner surface of cover)
20 ... Lens (projecting part)
22 ... Projection end (projection unit)
20a... Light receiving part side tip part (tip part) of the lens
22a ... Light receiving part side tip part (tip part) of the light projecting part
26: Axial line of light projecting unit 30: Light receiving end (light receiving unit)
30a: Light projecting portion side tip portion (tip portion) of the light receiving portion
36: Axis of light receiving portion 40: Light emitting area 41 ... Light receiving area 102 ... Light emitting element 103 ... Light receiving element

Claims (8)

A light projecting section (20, 22) that radiates light toward a detection target area as a detection target so as to form a predetermined radiation angle (α) and forms a light projection area (40);
A light receiving portion (30) that forms a light receiving area (41) having a predetermined light receiving angle (β) so as to receive the reflected light reflected by the light emitted from the light projecting portion hitting an object;
A light-transmitting cover (7) provided so as to cover the front side of the detection target area of the light projecting unit and the light receiving unit, and reflected light reflected by a hand entering the light projecting area An automatic faucet device that automatically discharges water when the light receiving part receives light,
The tip portion (20a, 22a) closest to the light receiving portion that emits light from the light projecting portion, and the tip closest to the light projecting portion that receives the reflected light of the light receiving portion. The installation interval with the part (30a) is
In the detection target area, the light projecting area and the light receiving area intersect to be set to a distance that forms a shared area,
Even if light traveling through the outermost part of the light emitted from the light projecting part is reflected by the cover and the adhering matter attached to the cover, the reflected light is set at a distance that is not received by the light receiving part. Automatic faucet device characterized by being made. The installation interval is D, the predetermined radiation angle is α, the inclination angle of the axis (26) of the light projecting unit with respect to the perpendicular direction of the cover inner surface (7a) is θ1, and the tip of the light projecting unit When the distance from the part (20a, 22a) to the cover is g1, and the distance from the tip part (30a) of the light receiving unit to the cover is g2,
The automatic faucet device according to claim 1, wherein the installation interval (D) is set so as to satisfy a relationship represented by the following formula 1.

The installation interval is D, the predetermined light receiving angle is β, the inclination angle of the axis (36) of the light receiving unit with respect to the perpendicular direction of the inner surface (7a) of the cover is θ2, and the tip portion of the light projecting unit When the distance from (20a, 22a) to the cover is g1, and the distance from the tip portion (30a) of the light receiving unit to the cover is g2,
The automatic faucet device according to claim 1, wherein the installation interval (D) is set so as to satisfy a relationship represented by the following expression 2.

The installation interval is D, the predetermined radiation angle is α, the inclination angle of the axis (26) of the light projecting unit with respect to the perpendicular direction of the cover inner surface (7a) is θ1, and the tip of the light projecting unit The distance from the part (20a, 22a) to the cover is g1, the distance from the tip part (30a) of the light receiving part to the cover is g2, the refractive index of air is n1, and the refractive index of the cover is When n2 and the thickness dimension of the cover is t,
The automatic faucet device according to claim 1, wherein the installation interval (D) is set so as to satisfy a relationship represented by the following Expression 3.

The installation interval is D, the predetermined light receiving angle is β, the inclination angle of the axis (36) of the light receiving unit with respect to the perpendicular direction of the inner surface (7a) of the cover is θ2, and the tip portion of the light projecting unit The distance from (20a, 22a) to the cover is g1, the distance from the tip part (30a) of the light receiving portion to the cover is g2, the refractive index of air is n1, and the refractive index of the cover is n2. When the thickness dimension of the cover is t,
The automatic faucet device according to claim 1, wherein the installation interval (D) is set so as to satisfy a relationship represented by the following expression (4).

The installation interval is D, the predetermined radiation angle is α, the inclination angle of the axis (26) of the light projecting unit with respect to the perpendicular direction of the cover inner surface (7a) is θ1, and the tip of the light projecting unit The distance from the part (20a, 22a) to the cover is g1, the distance from the tip part (30a) of the light receiving part to the cover is g2, the refractive index of air is n1, and the refractive index of the cover is When n2 is set, the thickness dimension of the cover is t, and the attachment surface length of water droplets or the like attached to the cover is a predetermined length W,
The automatic faucet device according to claim 1, wherein the installation interval (D) is set so as to satisfy a relationship represented by the following formula (5).

The installation interval is D, the predetermined light receiving angle is β, the inclination angle of the axis (36) of the light receiving unit with respect to the perpendicular direction of the inner surface (7a) of the cover is θ2, and the tip portion of the light projecting unit The distance from (20a, 22a) to the cover is g1, the distance from the tip part (30a) of the light receiving portion to the cover is g2, the refractive index of air is n1, and the refractive index of the cover is n2. When the thickness dimension of the cover is t, and the attachment surface length of water drops etc. attached to the cover is a predetermined length W,
The automatic faucet device according to claim 1, wherein the installation interval (D) is set so as to satisfy a relationship represented by the following expression (6).

  Furthermore, a light emitting element (102) that outputs light to the light projecting unit, a light projecting optical fiber (4) that guides light output from the light emitting element to the light projecting unit, and light received by the light receiving unit A light receiving element (103) to which light is input and a light receiving optical fiber (5) for guiding light received by the light receiving unit to the light receiving element. Automatic faucet device as described in.

Images