JP4048891B2 - Automatic faucet device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic faucet that is used for the purpose of hand-washing and the like, and automatically discharges water by detecting an object.
[0002]
[Prior art]
Automatic faucets that automatically detect water in toilets and toilets and detect dishes and pans in the kitchen are widely used. An infrared sensor is mostly used as a sensor for detecting an object of water discharge. Infrared light is emitted toward the object, and the presence or absence of an object is determined based on the magnitude or change of the infrared light reflected from the object.
[0003]
The faucet body of the automatic faucet is attached to the wash basin in the toilet and washroom, and to the sink in the kitchen. An example of a basin is shown in FIG . The detection direction of the sensor and the direction of water discharge are preferably the same from the viewpoint of ease of use, and the sensor is directed toward the basin as shown in FIG .
[0004]
The wash basin is generally made of earthenware and usually diffuses and reflects the infrared light emitted from the sensor on the earthenware surface. In the configuration of FIG. 8 , the distance between the sensor and the basin is farther than the distance between the sensor and the hand. Therefore, the reflected light from the hand becomes larger than the reflected light from the washbasin, and the automatic faucet can detect the hand.
[0005]
In this case, the closer the sensor is to the hand and the farther the sensor and the washbasin are, the smaller the reflection of infrared light from the washbasin becomes, and the usability of the automatic faucet is improved. In order to make this distance relationship ideal, there is a configuration in which a sensor is arranged at a water discharge port (see, for example, Patent Document 1).
[0006]
However, depending on the washbasin, infrared light may cause specular reflection on the ceramic surface instead of diffuse reflection, and return a large reflection to the sensor. Furthermore, kitchen sinks are generally made of stainless steel, and basins are made of shiny materials such as stainless steel and glass in addition to pottery, and infrared light also causes specular reflection.
[0007]
Such specular reflection causes a very high reflection level regardless of the distance to the sensor, and thus causes a malfunction of the automatic faucet. Even the method (Patent Document 1) in which the above-described sensor is disposed at the water discharge port portion can be improved only slightly.
[0008]
On the other hand, a polarizing means is incorporated into the light projecting / receiving part of the sensor to remove harmful specular reflection components and detect only diffuse reflection components such as hands, so that automatic water can be used regardless of the basin or sink material. A device for stably operating the stopper has been devised .
Combining the above-described device with Patent Document 1 realizes an easy-to-use automatic water faucet without malfunction due to mirror reflection of a basin or the like.
[0009]
An example of a structure in which a polarization unit is incorporated in a sensor is described as an example of a reflective photoelectric sensor using a regressive reflector (see, for example, Patent Document 2 ).
In Patent Document 2 , a polarizing plate is set in a sensor, and a transparent plate having no birefringence is fitted into a main body case in order to protect the polarizing filter on the outside thereof.
[0010]
[Patent Document 1]
Japanese Patent Laid-Open No. 2002-70096 (page 4, FIG. 1)
[Patent Document 2]
Japanese Patent Publication No. 6-93521 (page 4, Fig. 1)
[0011]
[Problems to be solved by the invention]
Since the sensor part of the automatic faucet is splashed with water during use or during cleaning, the sensor itself must be waterproof. If a polarizing plate, a polarizing beam splitter, or the like is used as the polarizing means, it is necessary to incorporate these into the waterproof structure sensor.
[0012]
However, the conventional structure as in Patent Document 2 cannot achieve a sufficient waterproof performance. The idea is to fit a polarizing plate and a protective cover into an existing sensor, and simple waterproof performance is the limit. In an environment exposed to water every day, such as an automatic faucet, parts such as a polarizing plate cannot be completely protected from water.
[0013]
Moreover, since the sensor of an automatic faucet affects the magnitude | size of the spout (water faucet main body) of an automatic faucet, it is requested | required that it is small from the point of design property. In addition, in terms of assembly and maintenance, a complicated shape for fixing to the spout is required so that it can be easily incorporated into and removed from the spout.
[0014]
FIG. 9 is a perspective view of the sensor unit of the automatic faucet of FIG. A cross-sectional view showing the internal structure is shown in FIG. In FIG. 10, reference numeral 11 denotes a case, and the material is a resin that transmits infrared light, and is generally manufactured by injection molding.
Reference numeral 2 denotes an infrared light emitting diode as a light projecting element, and 3 denotes a photodiode as a light receiving element, which is electrically connected to a circuit board 4 on which a signal processing circuit is mounted. In addition, a signal line 5 is connected to the circuit board 4 to input power and output signals.
[0015]
The light projecting element 2 and the light receiving element 3 are fixed to an element holder 61 in which a light projecting / receiving window is opened. The material of the element holder 61 is a resin that does not transmit infrared light. The element holder 61 holds a light projecting / receiving element and also has a role of shielding light between light projecting and receiving. The element holder 61 is also manufactured by injection molding.
[0016]
The element holder 61, the light projecting element 2, the light receiving element 3, and the circuit board 4 are assembled in the sensor case 11, and finally the casting agent 7 is poured into the sensor so that the sensor is hermetically sealed.
By selecting a material of the casting agent 7 that has good adhesion to the material of the sensor case 11, the waterproof performance of the sensor unit in FIG. 10 becomes strong.
FIG. 11 is an exploded view of FIG. 10 into constituent parts (excluding the casting agent 7).
[0017]
FIG. 11 is a perspective view when the polarizing plates 8 and 9 are incorporated in the sensor unit of FIG. 10 without changing the basic structure of the sensor.
The shapes of the polarizing plates 8 and 9 are rectangular, and the same polarizing plates are arranged orthogonally. 13 is a cross-sectional view showing the internal structure of FIG. If a space for the polarizing plate is provided on the element holder 6 side and the polarizing plates 8 and 9 are set here and assembled in the conventional manner, a waterproof structure is obtained. The optical positional relationship of the light projecting / receiving element is the same as that in FIG. 10 and has the least influence by incorporating the polarizing plate.
[0018]
However, in this configuration, there is a high possibility that the effect of incorporating the polarizing plate cannot be obtained due to the phenomenon of birefringence. Birefringence is a phenomenon in which the refractive index in a substance varies depending on the vibration direction of light, and particularly in a resin molded product, it is remarkably generated due to residual stress during molding.
[0019]
As shown in FIG. 9, the sensor case has a complicated structure in consideration of attachment to the faucet body and design, and is manufactured by injection molding. When the sensor case of FIG. 11 is injection-molded, the resin flow becomes complicated especially at the corners and the like, and a non-uniform portion of pressure tends to occur in the entire case, and there is a high possibility that birefringence occurs. When birefringence occurs in the sensor case, the polarization state changes when polarized infrared light passes through the sensor case, and the purpose of removing specular reflection cannot be achieved.
[0020]
In order to reduce birefringence, a resin material that hardly generates birefringence has been developed. However, it does not completely cause birefringence, and is expensive because it is special. Therefore, this problem cannot be solved by selecting a resin material.
[0021]
FIG. 14 is a cross-sectional view of a spout in which the sensor unit is disposed at the water discharge port. FIG. 15 is a cross-sectional view of the sensor unit. This type of sensor needs to be as small as possible to make the spout look thin.
As a factor that determines the size of the sensor, there is an interval of arrangement of the light projecting and receiving elements. Although the sensor can be miniaturized by arranging the light projecting / receiving element closer, it is necessary to separate the light emitting / receiving element to such an extent that no wraparound of infrared light through the water droplet occurs when the water droplet adheres to the sensor surface. Therefore, it is desirable to arrange them closer as long as they do not malfunction due to water droplets.
[0022]
FIG. 16 is a front view of the spout spout when a rectangular polarizing plate is set as shown in FIGS.
In order to identify the mounting direction of the polarizing plate, the shape is rectangular, but since the length of the long side of the rectangle is stored in the sensor, the thickness of the sensor increases as shown in FIG. End up.
Since the spout is the tip of the spout, if this part becomes large, the whole spout will become large, and the design of the automatic faucet will be damaged.
[0023]
The present invention has been made in order to solve the above-mentioned problems, and a polarizing plate is incorporated into a small and waterproof infrared sensor while maintaining its shape and waterproof performance, thereby demonstrating the effect thereof. It is to provide an automatic faucet that is not erroneously detected and excellent in design.
[0024]
[Means for Solving the Problems]
In order to achieve the above-mentioned target, the first aspect of the present invention projects a sensor unit that projects infrared light toward a detection body and detects the presence or absence of the detection body according to the amount of received infrared light reflected by the detection body. A faucet passage having a cylindrical spout at the tip, an electromagnetic valve for opening and closing the faucet passage, and an electromagnetic valve for controlling the electromagnetic valve based on a detection result by the sensor portion In the automatic water faucet device comprising the control means, the sensor section projects light means for projecting infrared light toward the detection body, and light reception means for receiving infrared light reflected by the detection body. A first polarizing plate disposed on the front surface of the light projecting means, a second polarizing plate disposed on the front surface of the light receiving means, and a sensor case for housing them, The edge of the case window that allows external light to pass through has a shape along the cylindrical shape of the spout. The water outlet and the sensor case are in contact with each other at this portion, the light projecting means and the light receiving means are disposed at a position perpendicular to the center of the water outlet, and the first and first Since the polarizing plate of No. 2 is arranged parallel to the tangent of the edge of the water outlet, the polarizing component transmitted by the first polarizing plate and the polarizing component transmitted by the second polarizing plate are orthogonal to each other. The polarizing plate can be orthogonalized only by the arrangement method of the polarizing plate, and the sensor can be miniaturized.
[0025]
According to a second aspect of the present invention, in the automatic water faucet device according to the first aspect, the first and second polarizing plates have a rectangular shape, and their long sides are arranged in parallel to the tangent of the edge of the water outlet. A rectangular polarizing plate excellent in mass productivity can be disposed with the polarization components orthogonal to each other while minimizing the shape of the sensor portion.
[0029]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail based on the embodiments shown in the drawings.
FIG. 1 is a sectional view of a sensor portion of an automatic faucet according to the first embodiment of the present invention. In FIG. 1, the components 2 to 9 except for the sensor case 1 are the same as those in FIG.
[0030]
In other words, the light projecting element 2 and the light receiving element 3 are fixed to an element holder 6 in which a light projecting / receiving window and a fixing space for a polarizing plate are opened, and are further electrically connected to the circuit board 4. A signal line 5 is connected to the circuit board 4. These parts are assembled in the sensor case 1, and finally the casting agent 7 is poured to seal the sensor.
[0031]
FIG. 2 is an exploded view of FIG. 1 into constituent parts (excluding the casting agent 7). In FIG. 2, the sensor case 1 is a component obtained by joining two components. In FIG. 2, reference numeral 101 denotes a window component of a light projecting / receiving surface through which infrared light of the sensor case 1 is transmitted, and has a substantially plate shape. Reference numeral 102 denotes a part of the case main body excluding the part 101 on the light projecting / receiving surface of the sensor case 1. Both parts 101 and 102 are manufactured by injection molding. The resin material of the component 101 is preferably a material that does not easily generate birefringence, while the resin material of the component 102 is not limited in optical performance.
[0032]
There are the following methods for connecting the component 101 and the component 102.
(1) Adhesion (2) Two-color molding (3) Insert molding (4) Ultrasonic welding [0033]
(1) is a method of bonding using an adhesive, but since the bonding is performed at the stage of a part called a sensor case, not at the time of assembling as a waterproof structure sensor, the choice of the adhesive expands.
If the procedure is to use an adhesive in a state where the polarizing plate is incorporated in the sensor, the curing time and curing temperature of the adhesive must be set to conditions that do not cause deterioration of the performance of the polarizing plate. In order to obtain sufficient waterproof performance, the adhesive should be selected with the highest priority on adhesive strength, and making the curing conditions of the adhesive compatible with maintaining the performance of the polarizing plate is a major limitation in selecting the adhesive.
But,
[0034]
The two-color molding of (2) is a method in which two resins are poured separately into the same mold, the adhesion of the joint surface is good, the two steps can be performed at once, and mass production is possible. Is excellent. By molding the case 1 by this method, the component 101 and the component 102 can be molded from different resins. In addition, by designing the component 101 into a simple shape such as a flat plate, it is possible to reduce the residual stress generated during molding as much as possible and to minimize the influence of birefringence.
[0035]
In the insert molding of (3), the part 101 is first molded, set in a mold for molding the part 102, and molded by pouring the resin of the part 102 part. Therefore, it takes time to set the component 101 in the mold, but insert molding does not require a dedicated injection molding machine such as the above two-color molding. Furthermore, the strength of the joint can be ensured even with resins having greatly different molding conditions, and the degree of freedom in resin selection is expanded. Further, by designing the component 101 in a simple shape such as a flat plate as in the above two-color molding, it is possible to reduce the residual stress generated during molding as much as possible.
[0036]
The ultrasonic welding (4) is a method in which the parts 101 and 102 are separately molded, and the resin at the joint portion is melted by ultrasonic energy. Although a dedicated device is required and the shape is slightly restricted by securing the welding surface, the components 101 and 102 can be manufactured and managed independently. This method also increases the degree of freedom of resin selection as in the above two molding methods, and can reduce the occurrence of residual stress as much as possible.
Further, at the time of welding, since there is almost no stress other than the welded portion, the polarizing plate can be sandwiched between the component 101 and the component 102.
[0037]
As described above, regardless of which of the methods (1) to (4) is selected, the part 101 can have a substantially plate shape, the flow of resin during injection molding is simplified, and the residual stress is minimized. Can be suppressed. Therefore, if a resin material that does not easily generate birefringence is used, the polarization performance is not deteriorated. Further, for joining the component 101 and the component 102, a strong means can be selected according to the sensor shape, and a good waterproof performance can be realized.
[0038]
FIG. 3 is a sectional view of a sensor portion of an automatic faucet according to the second embodiment of the present invention. The structure of FIG. 3 differs from the first embodiment of FIG. 2 in the sensor case and the element holder.
[0039]
An element holder 601 in FIG. 3 is a component in which the element holder 6 in FIG. 2 and the component 102 of the sensor case 1 are integrated. However, the resin material is a resin that does not transmit infrared light. Also, the component 101 in FIG. 2 is an independent component and serves as a sensor window 103.
The sensor window 103 is made of a resin material that hardly generates birefringence.
[0040]
In the assembly procedure, after the polarizing plates 8 and 9 are set in the element holder 601, the sensor window 103 is ultrasonically welded. If ultrasonic welding is used, no stress is applied to the polarizing plates 8 and 9, so there is no concern about performance degradation.
[0041]
Furthermore, since the element holder 601 plays a role as a case of the component 102 in FIG. 2, the outer shape of the sensor unit can be further reduced. In addition, sufficient waterproof performance is ensured.
[0042]
FIG. 4 is a front view of the spout portion of the automatic faucet according to the third embodiment of the present invention. The sensor is disposed in contact with the water outlet.
[0043]
In FIG. 4, the light projecting / receiving element is arranged so that the light projecting / receiving element forms an angle of 90 ° with respect to the center of the water outlet. As described above, the interval between the light projecting and receiving elements may be separated to such an extent that a malfunction does not occur when a water droplet is attached to the sensor surface, but FIG. 4 determines the arrangement from a different viewpoint.
[0044]
And the polarizing plates 8 and 9 are fixed so that the long side of the rectangle is in contact with the edge of the water outlet. With this arrangement, the polarizing plates 8 and 9 are in a positional relationship orthogonal to each other. Moreover, since the rectangular short side direction of a polarizing plate becomes the thickness of a sensor part, it is not necessary to increase the thickness of a sensor part, and the enlargement of a sensor by adding a polarizing plate can be avoided. Therefore, as shown in FIG. 5, the spout portion can be designed compactly.
[0045]
FIG. 6 is a cross-sectional view showing an example of the internal structure of the sensor unit of FIG. The configuration is the same as that of FIG. 1, and the same number is assigned to the functionally same component with respect to FIG. 1.
As in FIG. 1, the sensor case 1 is divided into components 101 and 102, so that the sensor can have a waterproof structure without disturbing the polarization state of infrared light.
[0046]
FIG. 7 is a cross-sectional view showing another example of the internal structure of the sensor unit of FIG. 3 is structurally similar to FIG. 3, and the same numbers are assigned to functionally identical parts with respect to FIG. As in FIG. 3, the outer shape of the sensor can be reduced by using ultrasonic welding.
[0047]
【The invention's effect】
As explained above, by constructing the waterproof sensor case with a combination of different parts, the part that becomes a problem when birefringence occurs can be made into a simple shape, the molding conditions can be easily controlled, and the birefringence becomes easier. The influence of can be suppressed.
Further, since the parts can be joined separately from the assembly of the polarizing plate, a joining means that places importance on waterproof performance can be selected.
Even if an expensive resin material having low birefringence is used, it is sufficient to use it only on the light projecting / receiving surface of the sensor, and the cost increase is small.
[0048]
If a method of ultrasonic welding to the sensor case with the light emitting / receiving surface of the sensor as a separate part is used, the case and the light projecting / receiving element holder can be integrated, which is effective for downsizing the sensor.
[0049]
In addition, in the sensor installed at the water outlet, by arranging the light projecting / receiving element at a position of 90 ° with respect to the center of the water outlet, the polarizing plate is orthogonally crossed just by placing the polarizer parallel to the edge of the water outlet. And the size of the sensor can be reduced.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a configuration of a sensor unit according to a first embodiment of the present invention.
FIG. 2 is a component diagram showing a configuration of a sensor unit according to the first embodiment of the present invention.
FIG. 3 is a cross-sectional view showing a configuration of a sensor unit according to a second embodiment of the present invention.
FIG. 4 is a front view of a water discharge port portion of an automatic faucet according to a third embodiment of the present invention.
FIG. 5 is a perspective view of a water discharge port portion of an automatic water faucet according to a third embodiment of the present invention.
FIG. 6 is a cross-sectional view showing a configuration of a sensor unit according to a third embodiment of the present invention.
FIG. 7 is a cross-sectional view showing a configuration of a sensor unit according to a fourth embodiment of the present invention.
FIG. 8 is a block diagram showing the positional relationship between the automatic faucet and the basin according to the present invention.
FIG. 9 is a perspective view of a sensor unit of a conventional automatic faucet.
FIG. 10 is a cross-sectional view showing a configuration of a sensor unit of a conventional automatic faucet.
FIG. 11 is a component diagram showing a configuration of a sensor unit of a conventional automatic faucet.
FIG. 12 is a perspective view in which a polarizing plate is incorporated in a sensor unit of a conventional automatic faucet.
FIG. 13 is a cross-sectional view showing a configuration in which a polarizing plate is incorporated in a sensor unit of a conventional automatic water faucet.
FIG. 14 is a cross-sectional view of a spout of an automatic faucet incorporating a conventional water outlet sensor.
FIG. 15 is a cross-sectional view showing a configuration of a water outlet sensor portion of a conventional automatic faucet.
FIG. 16 is a front view when a polarizing plate is incorporated in a water outlet sensor portion of a conventional automatic faucet.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Sensor case, 2 ... Light emitting element, 3 ... Light receiving element, 4 ... Circuit board,
DESCRIPTION OF SYMBOLS 5 ... Signal wire, 6 ... Element holder, 7 casting material, 8 ... Polarizing plate, 9 ... Polarizing plate 10 ... Basin, 11 ... Case, 12 ... Sensor accommodating part, 13 ... Water outlet 15 ... Faucet body, 61 ... Element holder 101 ... sensor case window, 102 ... sensor case body 103 ... sensor window, 601 ... element holder

Claims (2)

  A sensor unit that projects infrared light toward the detection body and detects the presence or absence of the detection body according to the amount of received infrared light reflected by the detection body, and a cylindrical discharge at the tip portion In an automatic faucet device comprising: a faucet channel having a water mouth; an electromagnetic valve for opening and closing the faucet channel; and an electromagnetic valve control means for controlling the electromagnetic valve based on a detection result by the sensor unit The sensor unit is disposed on a front surface of the light projecting unit, a light projecting unit that projects infrared light toward the detector, a light receiving unit that receives the infrared light reflected by the detector. A first polarizing plate, a second polarizing plate disposed on the front surface of the light receiving means, and a sensor case for storing them, and an edge of a case window portion through which infrared light of the sensor case is transmitted Is a shape along the cylindrical shape of the water discharge port. The case is configured to contact, the light projecting means and the light receiving means are disposed at a position perpendicular to the center of the water outlet, and one side of the first and second polarizing plates is the side An automatic water faucet device, which is arranged in parallel to a tangent of an edge of a water discharge port, wherein a polarization component transmitted by the first polarizing plate and a polarization component transmitted by the second polarizing plate are orthogonal to each other. 2. The automatic water faucet device according to claim 1, wherein the first and second polarizing plates have a rectangular shape, and their long sides are arranged in parallel to a tangent to the edge of the water outlet. Faucet device.

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