JP2018004605A - Transparency type optical coupling device and electric apparatus with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transparency type optical coupling device that accurately detect a storage level by preventing reflected light reflected by a boundary surface from being received by a light reception section, and an electric apparatus with the transparency type optical coupling device.SOLUTION: The present invention relates to a transparency type optical coupling device (50) capable of detecting a storage level of a light-transmissive liquid (70) stored in a light-transmissive container (4), the transparency type optical coupling device comprising: a light emission section (30) which emits light toward a side wall portion of the container; a light reception section (40) which receives light emitted from the light emission section and transmitted through the container; a level detection section (60b) which detects the storage level of the liquid reserved in the container on the basis of a light reception quantity of the light reception section; and an emission light restriction section (35a) which allows straight-traveling light, traveling straight to be emitted, of the light emitted from the light emission section to pass, but cuts off non-straight-traveling light transmitted in the liquid possibly to be reflected light reflected by a boundary surface 71 between the liquid and a gas contacting the liquid.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a transmission type optical coupling device and an electric apparatus including the device, and more particularly, to a transmission type optical coupling device that detects a storage level of a light-transmitting liquid stored in a light-transmitting container, and The present invention relates to an electric apparatus including the device.

  Patent Document 1 is composed of a light emitter that is disposed at a position that avoids the center of the inner wall of the drip tube, and a light receiver that is disposed at a position where light can be received when the drug solution in the drip tube is not on the emission line. Thus, a liquid level detection device including a detector fixed to the drip tube is disclosed.

  In Patent Document 2, the light emitting element and the light receiving element are arranged to face each other, and the optical axis connecting the light emitting element and the light receiving element is inclined with respect to the inner wall surface on the light incident side of the container to be measured. A positioned liquid detector is disclosed.

  In Patent Document 3, a light emitting means and a light receiving means are arranged with a part of a container or a liquid chamber communicating with the container interposed therebetween, and the transmitted light axis of the inner surface of the container or the liquid chamber is changed in the liquid level detecting means by changing the amount of transmitted light. Disclosed is a liquid level detecting means for forming a crossing portion with a highly wettable member.

Japanese Patent Laid-Open No. 02-295567 JP-A-61-270881 Japanese Patent Laid-Open No. 05-340791

  In the liquid level detection device of Patent Document 1, the liquid level is detected by using the refracting action of the drip tube and the chemical solution, and the light receiver becomes a position where light cannot be received or a position where light can be received depending on the presence or absence of the chemical solution. Thus, it is necessary to adjust the refractive action of the drip tube and the chemical solution.

  Also in the liquid detector of Patent Document 2, the liquid level is detected by using the refraction action of the container to be measured and the liquid, and the light receiving element is placed at a position where light cannot be received or a position where light can be received depending on the presence or absence of liquid. Thus, it is necessary to adjust the refractive action of the container to be measured and the liquid.

  In the liquid level detection means of Patent Document 3, the amount of transmitted light changes depending on whether or not the light from the light emitting means is blocked by ink with low light transmittance, and the height of the ink liquid level is detected by the change in the amount of transmitted light. In other words, the light shielding property of ink having very low light transmittance is utilized. Therefore, it is inappropriate to use a light-transmitting liquid as the liquid targeted by the liquid level detection means of Patent Document 3.

  As described above, Patent Literature 1 and Patent Literature 2 utilize the refraction action of the container to be measured and the liquid, and Patent Literature 3 utilizes a change in the amount of transmitted light. However, in Patent Document 3, the light shielding property of the ink is used, and there is a possibility that the ink is erroneously detected as having the light transmitting property.

  By the way, when the liquid level of a light-transmitting liquid is detected by a change in the amount of transmitted light, the light emitted from the light emitting unit may be directly received by the light receiving unit, that is, the direct light may be received by the light receiving unit. This is preferable in terms of accurate storage level detection. However, in reality, since the refractive index differs between the container and the liquid, an interface exists in the container storing the liquid. For example, there are a liquid surface and a bottom interface between the air and the liquid and between the bottom of the container and the liquid, respectively. Depending on the incident angle with respect to the interface, light incident on the interface is not transmitted but reflected by the interface. For this reason, the reflected light reflected from the liquid surface or bottom interface, that is, indirect light is received by the light receiving unit. When the reflected light is received by the light receiving unit, the amount of light received by the light receiving unit does not correspond to the liquid storage level and may be erroneously detected.

  Therefore, the technical problem to be solved by the present invention is to prevent the reflected light that is transmitted through the liquid and reflected at the interface between the liquid and the gas in contact with the liquid from being received by the light receiving unit, thereby accurately adjusting the storage level. It is another object of the present invention to provide a transmission type optical coupling device that detects the above and an electric device including the device.

  In order to solve the technical problem, according to the present invention, the following transmission type optical coupling device is provided.

A transmission type optical coupling device capable of detecting a storage level of a liquid having optical transparency stored in a container having optical transparency,
A light emitting part for emitting light toward the side wall part of the container;
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container;
Based on the amount of light received by the light receiving unit, a level detection unit that detects a storage level of the liquid stored in the container;
Among the light emitted from the light emitting part, the straight light emitted straightly in the direction of the light receiving part is allowed to pass, while being reflected at the interface between the liquid and the gas in contact with the liquid. And an outgoing light restricting portion that shields non-straight light that can be reflected light.

  Preferably, the emitted light restricting portion is an upper light shielding portion provided on the upper side of the light emitting portion.

  Preferably, as another outgoing light restricting portion, a lower light shielding portion provided below the light emitting portion is provided.

Preferably, the apparatus further comprises a container detection unit that detects that the container is attached to or detached from the predetermined location.
The container detection unit detects detachment of the container when the amount of light received by the light receiving unit is larger than the amount of light received when the liquid storage level is detected.

  Preferably, the level detection unit has hysteresis.

  Preferably, the light receiving unit performs an analog output corresponding to the amount of received light, and performs a filtering process or an averaging process on the analog output.

  Moreover, the electric equipment of this invention is equipped with the transmissive | pervious optical coupling device of any one of Claim 1-5.

Preferably, the light emitting part and the light receiving part are respectively disposed on adjacent side wall parts of the container so that light emitted from the light emitting part traverses a corner part of the container mounted on the electric device. The transmission type optical coupling device is configured,
The light emitting unit and the light receiving unit are disposed opposite to each other and optically coupled.

According to the present invention, an electric device including a transmission type optical coupling device capable of detecting a storage level of a light-transmitting liquid stored in a light-transmitting container,
A light emitting part for emitting light toward the side wall part of the container;
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container;
A level detection unit that detects a storage level of the liquid stored in the container based on the amount of light received by the light receiving unit;
The light emitting part and the light receiving part are respectively disposed on adjacent side wall parts of the container, and the light emitted from the light emitting part is transmitted through the corner part of the container mounted on the electric device. Type optical coupling device is configured,
There is provided an electric device in which light emitting edge light having a light emission directivity angle out of light emitted from the light emitting portion and a light receiving edge portion having a light reception directivity angle of light received by the light receiving portion are optically coupled.

Preferably, the light emitting unit and the light receiving unit respectively include a plurality of light emitting elements and a plurality of light receiving elements arranged in the depth direction of the container,
All of the plurality of light emitting elements in the light emitting unit emit light, and the light receiving unit outputs an output value corresponding to an addition value obtained by adding the respective photocurrent values generated by the plurality of light receiving elements.

Preferably, a container detection unit that detects that the container is attached or detached from a predetermined place;
A storage unit that stores the received light amount received by the light receiving unit as an initial received light amount when detachment of the container is detected by the container detection unit in an initial operation;
The received light amount received by the light receiving unit when the container detecting unit detects the detachment of the container and the initial received light amount stored in the storage unit, and the received light amount with respect to the initial received light amount A received light amount decrease detection unit for detecting whether or not the decrease in the amount is greater than a predetermined value;
A notification unit that notifies the decrease in the amount of received light when the decrease in the amount of received light with respect to the initial amount of received light is greater than a predetermined value.

  According to the transmission type optical coupling device of the present invention, the light emitted without going straight in the direction of the light receiving unit is blocked by the outgoing light regulating unit, so that the reflected light reflected at the interface in the container storing the liquid is reduced. Thus, the reflected light is less likely to be received by the light receiving unit. Therefore, erroneous detection due to reflected light can be prevented. Therefore, it is possible to prevent the reflected light reflected at the interface from being received by the light receiving unit, and to accurately detect the storage level of the liquid stored in the container.

The schematic front view of a heating cooker provided with the transmissive | pervious optical coupling device which concerns on 1st Embodiment of this invention. The schematic longitudinal cross-sectional view of the heating cooker shown in FIG. The control block diagram of the heating cooker shown in FIG. The schematic cross-sectional view of the said transmission type optical coupling device and the container in which this device was installed. The schematic longitudinal cross-sectional view of the transmissive | pervious optical coupling device shown in FIG. The model explanatory drawing of the light emission part in a transmissive | pervious optical coupling device. The transmissive | pervious optical coupling device which concerns on 2nd Embodiment of this invention, and the model cross section of the container in which this device was installed. The schematic longitudinal cross-sectional view when the corner part of the container in which the transmissive | pervious optical coupling device shown in FIG. 7 was installed was seen from the light emission part side. The schematic longitudinal cross-sectional view in the cross section containing the light emission part and the light-receiving part in the corner part of the container in which the transmissive | pervious optical coupling device shown in FIG. 7 was installed. The figure explaining the relationship between the storage level of the liquid in a container, and the output value in a light-receiving part. The circuit diagram when adding the photocurrent produced | generated by the several light receiving element. The figure explaining that the level detection part is comprised so that it may have a hysteresis so that the threshold value of the supply direction of a liquid may differ from the threshold value of a discharge direction. The schematic longitudinal cross-sectional view which shows the principal part of the transmissive | pervious optical coupling device which concerns on 4th Embodiment. The figure explaining the relationship between the storage level of the liquid in the container in the transmission type optical coupling device shown in FIG. 13, and the output value in a light-receiving part.

  Hereinafter, a cooking device 1 including a transmission type optical coupling device 50 according to a first embodiment of the present invention will be described with reference to the drawings. This embodiment is merely an example, and the present invention is not limited to this embodiment.

[First Embodiment]
FIG. 1 is a schematic diagram showing a state when the cooking device 1 including the transmissive optical coupling device 50 according to the first embodiment of the present invention is viewed from the front.

  As shown in FIG. 1, the heating cooker 1 has a rectangular parallelepiped main body casing 1a, a heating chamber 2 provided in the main body casing 1a, and a lower side on the front side of the main body casing 1a. A door 3 that is pivotably attached and a water supply tank 4 that is housed in the main casing 1a and is detachably attached are provided. The water supply tank 4 is an example of a container that stores water 70 as a light-transmitting liquid.

  An exhaust duct 5 having an outlet 5a is provided on the upper side and the rear side of the main casing 1a. The steam or the like in the heating chamber 2 is exhausted from the outlet 5a to the outside.

  The heating chamber 2 has an opening 2a on the front side for taking in and out the article to be heated 20 (shown in FIG. 2).

  The door 3 opens and closes the opening 2 a of the heating chamber 2. A transparent outer glass 6 having heat resistance is provided on the front surface of the door 3 (the surface opposite to the heating chamber 2). The door 3 has a handle 7 positioned on the upper side of the outer glass 6 and an operation panel 8 provided on the right side of the outer glass 6.

  The operation panel 8 includes a color liquid crystal display unit 9, a button group 10, and a dial 11. This group of buttons 10 includes a cancel button that is pressed when heating is stopped halfway or when the operation is repeated, and a warm start button that is pressed when range heating is automatically performed or other heating is started. And so on. The dial 11 is used to adjust the range output.

  When the water supply tank 4 is attached to the main body casing 1 a, the water supply tank 4 is positioned below the right portion of the door 3. At this time, the front surface of the water supply tank 4 is exposed without being covered with other members. The water supply tank 4 is made of a light-transmissive resin member (for example, polycarbonate).

  As shown in FIGS. 4 and 5, the water supply tank 4 has a rectangular parallelepiped shape as a whole, and includes a lid 4a, a light emitting side wall 4b, a light receiving side wall 4c, two other side walls, and a bottom surface 4d. It is comprised from the housing | casing which has. The bottom surface portion 4d on the light-receiving side wall portion 4c side is formed with an inclined portion 4e that is inclined upward toward the light-receiving side wall portion 4c. A corner portion 4f is formed at a portion where the light emitting side wall portion 4b and the light receiving side wall portion 4c, which are adjacent side wall portions, intersect and in the vicinity thereof.

  When the water 70 (liquid) is stored in the water supply tank 4, a liquid level 71 (interface) is formed between the water 70 and the air 74 (gas) in contact with the water 70. Further, a bottom interface 72 (interface) is formed between the water 70 and the bottom surface portion 4 d of the water supply tank 4 in contact with the water 70.

  FIG. 2 is a schematic diagram showing a cross section of the cooking device 1 cut along a vertical plane parallel to the front-rear direction.

  A steam generator 12 is installed inside the main casing 1a and outside the heating chamber 2. The steam generator 12 heats the water 70 from the water supply tank 4 by heating with a heater to supply the steam into the heating chamber 2, or further heats the steam with a heater to supply superheated steam into the heating chamber 2. Or At this time, water is supplied from the water supply tank 4 to the water vapor generator 12 by a water supply pump 13 (shown in FIG. 3). In addition, superheated steam is the steam which became the temperature exceeding 100 degreeC.

  Further, an antenna 15 for agitating the microwave generated by the magnetron 14 (shown in FIG. 3) is installed below the heating chamber 2. The antenna 15 is rotationally driven by a motor 19.

  The heating chamber 2 is formed so as to accommodate the tray 16 on which the article to be heated 20 is mounted. The tray 16 is supported by a shelf holder (not shown) on the inner wall surface of the heating chamber 2. Further, the object to be heated 20 on the tray 16 is heated by water vapor or superheated water vapor from the water vapor generating device 12 or is heated by radiant heat of the upper heater 17 or the lower heater 18. Further, the top wall of the heating chamber 2 is located below the upper heater 17, and the bottom wall of the heating chamber 2 is located above the lower heater 18, so that the upper heater 17 and the lower heater 18 are not exposed in the heating chamber 2. . The bottom wall is made of ceramic, and the walls other than the bottom wall of the heating chamber 2 are made of metal.

  The heating cooker 1 also includes a transmissive optical coupling device 50 that detects the storage level of the water 70 stored in the water supply tank 4. The transmissive optical coupling device 50 is installed on the rear side of the water supply tank 4 attached to the main body casing 1 a, that is, on the opposite side to the take-out side of the water supply tank 4.

  The transmissive optical coupling device 50 includes a light emitting unit 30 that emits light toward the light emitting side wall 4b of the water supply tank 4, and a light receiving unit 40 that receives light emitted from the light emitting unit 30 and transmitted through the water supply tank 4. And a support 52 for supporting the light emitting unit 30 and the light receiving unit 40 and attaching them to the main body casing 1a.

  The light emitting unit 30 includes at least one light emitting element that emits near-infrared light. In this embodiment, three light emitting elements arranged in the depth direction of the water supply tank 4, that is, the first light emitting element 31 and the second light emitting element 30. The light emitting element 32 and the third light emitting element 33 are included. The light emitting unit 30 is configured to emit light substantially horizontally toward the light emitting side wall portion 4 b of the water supply tank 4. Each of the light emitting elements 31, 32, and 33 is, for example, a light emitting diode that emits near infrared light, and is mounted on the light emitting substrate 34.

  The light receiving unit 40 includes at least one light receiving element corresponding to the light emitting element of the light emitting unit 30. In this embodiment, three light receiving elements arranged in the depth direction of the water supply tank 4, that is, a first light receiving element 41 and A second light receiving element 42 and a third light receiving element 43 are included. The light receiving unit 40 receives light emitted from the light emitting unit 30 substantially horizontally and transmitted through the water supply tank 4 substantially horizontally. Each of the light receiving elements 41, 42, 43 is, for example, a photodiode that receives near-infrared light, and is mounted on the light receiving substrate 44. The light receiving unit 40 outputs an output value (for example, an output voltage) corresponding to the amount of light received by each of the light receiving elements 41, 42, and 43.

  FIG. 3 is a control block diagram of the heating cooker 1.

  The heating cooker 1 includes a control device 60 including a microcomputer and an input / output circuit. The control device 60 includes a magnetron 14, an operation panel 8, a water vapor generator 12, a water supply pump 13, an upper heater 17, a lower heater 18, a motor 19, a storage unit 22, a notification unit 23, a light emitting unit 30, a light receiving unit 40, and the like. Is connected.

  The control device 60 controls the magnetron 14, the operation panel 8, the water vapor generation device 12, the water supply pump 13, the upper heater 17, the lower heater 18, the motor 19 and the like based on the signal from the operation panel 8. Further, the control device 60 controls the light emission of the light emitting unit 30 and detects the storage level of the water 70 in the water supply tank 4 based on the output value from the light receiving unit 40 that receives the light from the light emitting unit 30. . That is, the control device 60 detects the presence / absence of the water supply tank 4 and the presence / absence of the water 70 stored in the water supply tank 4 based on the output value from the light receiving unit 40 of the transmissive optical coupling device 50. The magnitude of the amount of light received by the light receiving unit 40 is such that when the water supply tank 4 is not attached, the water supply tank 4 is attached, and when the water 70 is not stored in the water supply tank 4, the water supply tank 4 is When the water 70 is stored and stored in the water supply tank 4, the size increases in the order.

  The storage unit 22 stores various control programs for exchanging various information with the control device 60. And the memory | storage part 22 memorize | stores the light reception amount which the light-receiving part 40 received when the detachment | desorption of the water supply tank 4 was detected by the container detection part 60a in the operation | movement initial stage as an initial light reception amount. The storage unit 22 includes a ROM (Read Only Memory) and a RAM (Random Access Memory).

  The notification unit 23 is used to notify the decrease in the amount of received light when the decrease in the amount of received light with respect to the initial amount of received light is greater than a predetermined value. The notification unit 23 notifies the speaker by voice or visually by the display unit.

  The control device 60 includes a container detection unit 60a, a level detection unit 60b, and a received light amount decrease detection unit 60c.

  The container detection unit 60a determines whether the water supply tank 4 is attached or detached at a predetermined position of the main casing 1a based on the amount of light received by the light receiving unit 40, that is, the output value output from the light receiving unit 40. Then, the presence or absence of the water supply tank 4 is detected.

  The level detection unit 60b determines whether the water 70 is in a certain storage level in the water supply tank 4 based on the amount of light received by the light receiving unit 40, that is, the output value output from the light receiving unit 40. The storage level of the water 70 stored in the tank 4 is detected.

  The received light amount decrease detection unit 60c compares the received light amount received by the light receiving unit 40 when the container detection unit 60a detects the detachment of the water supply tank 4 with the initial received light amount stored in the storage unit 22. Then, it is detected whether or not the decrease in the amount of received light with respect to the initial amount of received light is greater than a predetermined value.

  And the container detection part 60a, the level detection part 60b, and the light reception amount fall detection part 60c are each comprised from the software.

  Between the light emission part 30 and the light emission side wall part 4b of the water supply tank 4, the emitted light regulation part 35a and the other emitted light regulation part 35b are provided. The outgoing light restricting part 35a and the other outgoing light restricting part 35b are incorporated as a part of the light emitting part 30, and emit light so as to cover the light emitting side of the light emitting elements 31, 32, 33 except for the part where the outgoing light is emitted. Arranged in the vicinity of the elements 31, 32 and 33. In addition, you may arrange | position the emitted light regulation part 35a and the other emitted light regulation part 35b in the intermediate part of the light emission part 30 and the light emission side side wall part 4b on the light emission side side wall part 4b side.

  On the emission side of the light emitting elements 31, 32, 33, the light is emitted by going straight in the direction of the upper light shielding part 35a as an outgoing light restricting part, the lower light shielding part 35b as another outgoing light restricting part, and the light receiving part 40. An exit opening 35c that allows straight light to pass therethrough is provided. The upper light-shielding part 35a shields non-straight light that can be reflected light that is transmitted through the water 70 and reflected by the liquid surface 71 (interface) without going straight in the direction of the light receiving part 40. The lower light-shielding part 35b shields non-straight light that can be reflected light that passes through the water 70 and reflects at the bottom interface 72 (interface) without going straight in the direction of the light-receiving part 40. Accordingly, the outgoing light restricting portion 35a and the other outgoing light restricting portions 35b are allowed to pass the straight light emitted straightly traveling in the direction of the light receiving portion 40, while not traveling straight in the direction of the light receiving portion 40. Non-straight light that can be reflected light at 71 (interface) and bottom interface 72 (interface) is shielded.

  The upper light shielding part 35a is provided on the upper side of the light emitting part 30, and shields light emitted upward. That is, the light is emitted upward from the optical axis of the light emitting unit 30, and the liquid level 71 of the water 70 is emitted in the direction of the liquid level 71 of the water 70 stored in the water supply tank 4 located above the optical axis of the light emitting unit 30. To block the light. When the light emitting unit 30 includes a plurality of light emitting elements (for example, the first light emitting element 31, the second light emitting element 32, and the third light emitting element 33), the upper light shielding part 35a is provided above each of the light emitting elements 31, 32, and 33, respectively. Provided. The upper light shielding portion 35 a provided in the second light emitting element 32 has a function of preventing the light emitted from the second light emitting element 32 from being received by the first light receiving element 41. Further, the upper light shielding portion 35 a provided in the third light emitting element 33 has a function of preventing the light emitted from the third light emitting element 33 from being received by the first light receiving element 41 and the second light receiving element 42. . The upper light-shielding portion 35a can prevent so-called crosstalk from occurring between the light emitting element and the light receiving element that are not paired.

  The lower light-shielding part 35b is provided on the lower side of the light emitting part 30, and shields light emitted downward. That is, it is emitted below the optical axis of the light emitting unit 30, and the liquid level 71 of the water 70 is in the direction of the bottom surface 4 d of the water supply tank 4 in which the water 70 is stored above the optical axis of the light emitting unit 30. Light emitted in the direction of the interface 72 is shielded. When the light emitting unit 30 includes a plurality of light emitting elements (for example, the first light emitting element 31, the second light emitting element 32, and the third light emitting element 33), the lower light shielding part 35 b is provided on the lower side of each light emitting element 31, 32, 33. Are provided respectively. The lower light shielding portion 35 b provided in the first light emitting element 31 has a function of preventing the light emitted from the first light emitting element 31 from being received by the second light receiving element 42 and the third light receiving element 43. Further, the lower light-shielding portion 35 b provided in the second light emitting element 32 has a function of preventing the light emitted from the second light emitting element 33 from being received by the third light receiving element 43. The lower light shielding portion 35b can prevent so-called crosstalk from occurring between the light emitting element and the light receiving element that are not paired.

  The upper light-shielding portion 35a and the lower light-shielding portion 35b have a plate shape extending in the vertical direction (vertical direction), a plate shape extending in the straight traveling direction (lateral direction) of the emitted light, or the vertical direction (vertical direction) and the straight traveling direction (lateral direction). ). The plate-shaped upper light-shielding part 35a and the lower light-shielding part 35b can have, for example, a flat plate shape, a curved shape, or a triangular (gable) roof shape. When the upper light-shielding portion 35a has a curved shape or a triangular (gable) roof shape, it has a shape protruding upward. Moreover, when the lower light-shielding part 35b has a curved shape or a triangular (gable) roof shape, it has a shape protruding downward.

  The light emitting unit 30 may further include a connected light shielding part 35d that connects the upper light shielding part 35a and the lower light shielding part 35b as a light shielding part. When the center light La of the emitted light is used for optical coupling, for example, as shown in FIG. 6, a closed loop shape including a connected light shielding portion 35d that connects the left and right sides of the upper light shielding portion 35a and the lower light shielding portion 35b. It can be. According to the closed loop-shaped light shielding portion, light emitted in the vertical and horizontal directions is shielded. Examples of the closed loop shape include a polygonal shape such as a circular shape, a track shape, a triangular shape, a square shape, a rectangular shape, and a trapezoidal shape.

  In order to prevent the reflected light reflected by the liquid level 71 and the bottom interface 72 from being received, light reception similar to that of the outgoing light restricting portion 35a is provided between the light receiving portion 40 and the light receiving side wall portion 4c of the water supply tank 4. A restricting portion 45a and another light receiving restricting portion 45b similar to the other emitted light restricting portions 35b are provided. The light receiving restricting part 45a and the other light receiving restricting part 45b are incorporated as a part of the light receiving part 40, and the light receiving elements 41, 42 are covered so as to cover the light receiving side of the light receiving elements 41, 42, 43 except for the light receiving part. , 43 in the vicinity. Note that the light receiving restriction part 45a and the other light receiving restriction part 45b may be disposed on the light receiving side wall part 4c side, or in an intermediate part between the light receiving part 40 and the light receiving side wall part 4c.

  On the light receiving side of the light receiving elements 41, 42, 43, there are provided an upper light shielding part 45a as a light receiving restriction part, a lower light shielding part 45b as another light receiving restriction part, and a light receiving opening 45c through which straight light can pass. It has been.

  The upper light shielding unit 45a is provided on the upper side of the light receiving unit 40 and shields light incident from above. That is, the light that is emitted above the optical axis of the light emitting unit 30 and the liquid level 71 of the water 70 is reflected by the liquid level 71 of the water 70 stored in the water supply tank 4 that is above the optical axis of the light emitting unit 30. (Non-straight light) is shielded. When the light receiving unit 40 includes a plurality of light receiving elements (for example, the first light receiving element 41, the second light receiving element 42, and the third light receiving element 43), the light receiving units 40 are provided above the respective light receiving elements 41, 42, and 43. The upper light shielding portion 45 a provided in the second light receiving element 42 has a function of shielding the light emitted from the first light emitting element 31. The upper light shielding portion 45 a provided in the third light receiving element 43 has a function of shielding light emitted from the first light emitting element 31 and the second light emitting element 32. The upper light shielding portion 45a can prevent so-called crosstalk from occurring between the light emitting element and the light receiving element that are not paired.

  The lower light-shielding part 45b is provided below the light-receiving part 40 and shields light incident from below. That is, the bottom surface portion 4d of the water supply tank 4 in which the water 70 is emitted below the optical axis of the light emitting unit 30 and the water surface 71 of the water 70 is above the optical axis of the light emitting unit 30 is stored. The light reflected at 72 (non-straight light) is shielded. When the light receiving unit 40 includes a plurality of light receiving elements (for example, the first light receiving element 41, the second light receiving element 42, and the third light receiving element 43), the lower light shielding part 45 b is provided on the lower side of each light receiving element 41, 42, 43. Are provided respectively. The lower light shielding portion 45 b provided in the first light receiving element 41 has a function of shielding light emitted from the second light emitting element 32 and the third light emitting element 33. The lower light shielding part 45 b provided in the second light receiving element 42 has a function of shielding light emitted from the third light emitting element 33. The lower light shielding portion 45b can prevent so-called crosstalk from occurring between the light emitting element and the light receiving element that are not paired.

  The upper light-shielding portion 45a and the lower light-shielding portion 45b have a plate shape extending in the vertical direction (longitudinal direction), a plate shape extending in the straight traveling direction (lateral direction) of incident light, or the vertical direction (vertical direction) and the straight traveling direction (lateral direction). ). The plate-shaped upper light-shielding portion 45a and lower light-shielding portion 45b can be formed into, for example, a flat plate shape, a curved shape, or a triangular (gable) roof shape. When the upper light-shielding part 45a has a curved shape or a triangular (gable) roof shape, it has a shape protruding upward. Moreover, when the lower light-shielding part 45b has a curved shape or a triangular (gable) roof shape, it has a shape protruding downward.

  The light receiving unit 40 may further include a connected light blocking unit that connects the upper light blocking unit 45a and the lower light blocking unit 45b as the light blocking unit. When the center light La of the emitted light is used for optical coupling, it can be formed into a closed loop shape including a connected light shielding part that connects the left and right sides of the upper light shielding part 45a and the lower light shielding part 45b. According to the closed loop-shaped light shielding portion, light received in the vertical and horizontal directions is shielded. Examples of the closed loop shape include a polygonal shape such as a circular shape, a track shape, a triangular shape, a square shape, a rectangular shape, and a trapezoidal shape.

  With reference to FIGS. 4, 5, 10, 11, and 12, a method of detecting the storage level of the water 70 stored in the water supply tank 4 using the transmissive optical coupling device 50 will be described.

  FIG. 4 is a cross-sectional view schematically showing the transmissive optical coupling device 50 and the water supply tank 4 in which the device 50 is installed. FIG. 5 is a longitudinal sectional view schematically showing the transmission type optical coupling device 50 and the water supply tank 4 shown in FIG.

  The transmissive optical coupling device 50 is configured to fit the corner portion 4f on the rear side of the water supply tank 4 attached to the main casing 1a. The light receiving unit 40 is disposed to face the light emitting unit 30 so that the light emitted from the light emitting unit 30 toward the light emitting side wall 4b crosses the corner 4f on the rear side of the water supply tank 4. That is, the light emitted from the light emitting unit 30 passes through the light emitting side wall portion 4b of the water supply tank 4, the water 70 stored in the water supply tank 4, and the light receiving side wall portion 4c of the water supply tank 4 to receive light. The light emitting unit 30 and the light receiving unit 40 are arranged so as to be received by the unit 40.

  In the transmissive optical coupling device 50 shown in FIG. 4, the light emitted from the light emitting unit 30 is emitted from the light emitting side wall portion 4 with respect to the water supply tank 4 in which the light emitting side wall portion 4 b and the light receiving side wall portion 4 c form a right angle. The light emitting unit 30 is positioned obliquely so as to form a certain angle with respect to 4b. The light receiving unit 40 is positioned obliquely so that the light received by the light receiving unit 40 forms an additional angle of the certain angle with respect to the light receiving side wall 4c. For example, the light emitted from the light receiving unit 40 forms an angle of 45 degrees with respect to the light receiving side wall 4c, and the light received by the light receiving unit 40 forms an angle of 45 degrees with respect to the light receiving side wall 4c.

  The first light emitting element 31 and the first light receiving element 41 form a pair, and the light emitted from the first light emitting element 31 of the light emitting unit 30 is received by the first light receiving element 41 of the light receiving unit 40. Similarly, the second light emitting element 32 and the second light receiving element 42 form a pair, and the light emitted from the second light emitting element 32 is received by the second light receiving element 42. In addition, the third light emitting element 33 and the third light receiving element 43 form a pair, and the light emitted from the third light emitting element 33 is received by the third light receiving element 43. The first light emitting element 31 and the first light receiving element 41, the second light emitting element 32 and the second light receiving element 42, the third light emitting element 33 and the third light receiving element 43, in order from the top in the depth direction of the water supply tank 4. Is arranged.

  Of the light emitted from the first light emitting element 31, the light emitted in the direction of the liquid level 71 is blocked by the upper light blocking portion 35 a, and the reflected light is prevented from being generated on the liquid level 71. Thereby, the reflected light at the liquid level 71 is prevented from being received by the first light receiving element 41. Of the light emitted from the first light emitting element 31, the light emitted in the direction of the bottom interface 72 is blocked by the lower light shielding portion 35 b, thereby preventing the reflected light from being generated at the bottom interface 72. Thereby, the reflected light at the bottom interface 72 is prevented from being received by the first light receiving element 41. In addition, light emitted from light emitting elements (second light emitting element 32 and third light emitting element 33) other than the first light emitting element 31 forming a pair with the first light receiving element 41 is directly received by the first light receiving element 41. Is prevented. Therefore, among the light emitted from the first light emitting element 31, the central light La that is around the optical axis and has a relatively large luminous intensity is optically coupled to the first light receiving element 41. That is, the central light La emitted from the first light emitting element 31 is directly received by the first light receiving element 41, and the direct light from the first light emitting element 31 is received by the first light receiving element 41.

  Similarly, of the light emitted from the second light emitting element 32, the central light La that is around the optical axis and has a relatively large luminous intensity is optically coupled to the second light receiving element 42, and the second light receiving element. Light is directly received by the element 42. Of the light emitted from the third light emitting element 33, the center light La that is around the optical axis and has a relatively large luminous intensity is optically coupled to the third light receiving element 43. Light is received directly.

  Accordingly, the storage level at the upper position is detected by the first light emitting element 31 and the first light receiving element 41, the storage level at the intermediate position is detected by the second light emitting element 32 and the second light receiving element 42, and the third light emitting element 33 and The storage level at the lower position is detected by the third light receiving element 43.

  As described above, the light receiving unit 40 is disposed facing the light emitting unit 30 so that the light emitted from the light emitting unit 30 toward the light emitting side wall 4b crosses the corner 4f on the rear side of the water supply tank 4. Has been. Thereby, compared with the case where the light emission part 30 and the light-receiving part 40 are each installed in the side wall part which opposes in the water supply tank 4, the optical path length from the light emission part 30 to the light-receiving part 40 becomes short, and it is based on the shift | offset | difference of an optical axis. It is possible to prevent a decrease in optical coupling property.

  FIG. 11 is a circuit diagram when the photocurrents generated by a plurality of light receiving elements (the first light receiving element 41, the second light receiving element 42, and the third light receiving element 43) are added.

The control device 60 controls all the light emitting elements 31, 32, and 33 of the light emitting unit 30 to emit light. When the light receiving unit 40 receives the light emitted from each of the light emitting elements 31, 32, and 33, the light receiving elements 41, 42, and 43 of the light receiving unit 40 have photocurrent values I ₁ and I according to the amount of received light. ₂ and I ₃ are output. The light receiving unit 40 outputs an added value obtained by adding the photocurrent values I ₁ , I ₂ , and I ₃ as an output value (for example, an output voltage). By outputting one added value obtained by adding the respective photocurrent values I ₁ , I ₂ , and I ₃ , the circuit configuration related to the output at the light receiving unit 40 can be simplified.

  The level detection unit 60b detects the storage level based on the output value (for example, output voltage) output by the light receiving unit 40. That is, an output value (for example, output voltage) output by the light receiving unit 40 is A / D converted by, for example, a microcomputer, and the converted digital signal is compared with a value corresponding to each storage level. The level is detected.

  FIG. 10 shows the relationship between the storage level of the water 70 in the water supply tank 4 and the output value (for example, output voltage) at the light receiving unit 40, and the attachment or removal of the water supply tank 4 at a predetermined position of the main body casing 1a. The relationship between the separation and the output value (for example, output voltage) at the light receiving unit 40 is schematically shown. In FIG. 10, the horizontal axis indicates the storage level of the water 70 in the water supply tank 4, and the vertical axis indicates the output value (for example, output voltage) at the light receiving unit 40. In addition, each numerical value shown on the horizontal axis and the vertical axis is an example for facilitating understanding, and is not limited to the numerical value.

  As described above, all of the light emitting elements 31, 32, and 33 of the light emitting unit 30 emit light, and the light receiving unit 40 outputs an output value (for example, an amount of light received by each of the light receiving elements 41, 42, and 43) (for example, Output voltage).

  A state in which the water supply tank 4 mounted at a predetermined position of the main casing 1a is substantially filled with water 70 is defined as an initial full water state. Then, a state in which the storage level (liquid level 71) of the water 70 in the water supply tank 4 gradually decreases due to water supply to the steam generator 12, that is, drainage from the water supply tank 4, will be described.

  In the initial full water state, the water 70 storage level (liquid level 71) is above the optical axis of the first light emitting element 31 and the first light receiving element 41, so that the water supply tank 4 and the water supply tank 4 are filled. The light transmitted through the water 70 is not received by the light receiving elements 41, 42, 43. Each output value output according to the amount of light received by each light receiving element 41, 42, 43 is added, but each light receiving element 41, 42, 43 receives light transmitted through the water supply tank 4 and water 70. The added value obtained by adding the output values is the lowest. Therefore, the output value output from the light receiving unit 40 in the initial full state is the lowest value as the output value A, and is 0 in the ideal state.

  Even in a high water storage stage where a little drainage is discharged from the full water state, the state in which the storage level (liquid level 71) of the water 70 is located above the optical axes of the first light emitting element 31 and the first light receiving element 41 continues. The output value from the light receiving unit 40 has a certain output value A.

  When further drainage is performed, the storage level (liquid level 71) of the water 70 becomes the first water storage stage located in the vicinity of the optical axis of the first light emitting element 31 and the first light receiving element 41. In the first water storage stage, the light emitted from the first light emitting element 31 is not affected by the water 70 of the water supply tank 4, so that the amount of light received by the first light receiving element 41 is increased and the output from the first light receiving element 41 is increased. The value increases.

  However, the output value is affected by the emission opening 35 c of the first light emitting element 31 and the light receiving opening 45 c of the first light receiving element 41. That is, the first light emitting element 31 has a certain opening width in the depth direction of the water supply tank 4, and the first light receiving element 41 also has a certain opening width in the depth direction of the water supply tank 4. The range that can be detected by the element 31 and the first light receiving element 41 also has a certain width in the depth direction of the water supply tank 4. In the pair of the first light emitting element 31 and the first light receiving element 41, the ratio of the emission opening 35c and the light receiving opening 45c shielded by water 70, that is, the aperture light shielding ratio (the emission opening 35c of the first light emitting element 31 and the first light receiving element 41). The total light shielding area obtained by summing the light shielding areas of the light emitting opening 35c of the first light emitting element 31 and the light receiving opening 45c of the first light receiving element 41 which are shielded by water 70 with respect to the total opening area obtained by summing the opening areas of the light receiving openings 45c. Area) changes according to the storage level of the water 70 (the liquid level 71). Therefore, when the storage level (liquid level 71) of the water 70 is reduced in the first water storage stage, the aperture light shielding ratio in the first light emitting element 31 and the first light receiving element 41 is reduced, so that the output from the first light receiving element 41 is reduced. The value changes while gradually increasing as the output value B. That is, the output value B increases with increasing left shoulder. Note that the above description is based on the premise that the light amounts of the emitted light and the incident light are uniform within the respective opening surfaces in the light emitting opening 35c of the first light emitting element 31 and the light receiving opening 45c of the first light receiving element 41. I have to.

  When further drainage is performed, the storage level (liquid level 71) of the water 70 is located below the optical axis of the first light emitting element 31 and the first light receiving element 41, and the second light emitting element 32 and the second light receiving element. It becomes the middle water storage stage where the state located above the optical axis of 42 continues. Therefore, in the middle water storage stage, the output value has a certain output value C.

  When further drainage is performed, the storage level (liquid level 71) of the water 70 is in the second water storage stage where the second light emitting element 32 and the second light receiving element 42 are located in the vicinity of the optical axis. In the second water storage stage, the light emitted from the second light emitting element 32 is not affected by the water 70 of the water supply tank 4, so that the amount of light received by the second light receiving element 42 is increased and output from the second light receiving element 42. The value increases. Similar to the first light emitting element 31 and the first light receiving element 41 described above, the output value is affected by the emission opening 35 c of the second light emitting element 32 and the light receiving opening 45 c of the second light receiving element 42. That is, since the second light emitting element 32 has a certain opening width in the depth direction of the water supply tank 4, and the second light receiving element 42 also has a certain opening width in the depth direction of the water supply tank 4, The range that can be detected by the element 32 and the second light receiving element 42 also has a certain width in the depth direction of the water supply tank 4. In the pair of the second light emitting element 32 and the second light receiving element 42, the ratio of the emission opening 35c and the light receiving opening 45c shielded by the water 70, that is, the aperture light shielding ratio (the emission opening 35c of the pair of second light emitting element 32 and the second light receiving element). The total light-shielding areas of the light-emitting openings 35c of the second light-emitting elements 32 and the light-receiving openings 45c of the second light-receiving elements 42, which are shielded by water 70, are totaled with respect to the total aperture area obtained by summing the areas of the light-receiving openings 45c of the elements 42 The total light shielding area) changes according to the storage level of the water 70 (the liquid level 71). Therefore, when the storage level (liquid level 71) of the water 70 decreases in the second water storage stage, the aperture light shielding ratio in the second light emitting element 32 and the second light receiving element 42 decreases, so that the output from the second light receiving element 42 The value changes while gradually increasing as the output value D. That is, the output value D increases with increasing left shoulder. Note that the above description is based on the premise that the light amounts of the emitted light and the incident light are uniform within the respective opening surfaces in the light emitting opening 35c of the second light emitting element 32 and the light receiving opening 45c of the second light receiving element 42. I have to.

  When further drainage is performed, the storage level (liquid level 71) of the water 70 is located below the optical axis of the second light emitting element 32 and the second light receiving element 42, and the third light emitting element 33 and the third light receiving element. It becomes the low water storage stage where the state located above 43 optical axes continues. Therefore, in the low water storage stage, the output value has a certain output value E.

  When further drainage is performed, the storage level (liquid level 71) of the water 70 becomes the third water storage stage located near the optical axis of the third light emitting element 33 and the third light receiving element 43. In the third water storage stage, since the light emitted from the third light emitting element 33 is not affected by the water 70 of the water supply tank 4, the amount of light received by the third light receiving element 43 is increased and the light from the third light receiving element 42 is increased. The output value increases. Similar to the first light emitting element 31 and the first light receiving element 41 described above, the output value is affected by the emission opening 35 c of the third light emitting element 33 and the light receiving opening 45 c of the third light receiving element 43. That is, the third light emitting element 33 has a certain opening width in the depth direction of the water supply tank 4, and the third light receiving element 43 also has a certain opening width in the depth direction of the water supply tank 4. The range that can be detected by the element 33 and the third light receiving element 43 also has a certain width in the depth direction of the water supply tank 4. In the pair of third light emitting element 33 and third light receiving element 43, the ratio of the light emitting opening 35c and the light receiving opening 45c shielded by water 70, that is, the aperture light shielding ratio (the light emitting opening 35c and third light receiving of the pair of third light emitting element 33). The total light-shielding area of the light-emitting opening 35c of the third light-emitting element 33 and the light-receiving opening 45c of the third light-receiving element 43, which are shielded by water 70, is added to the total opening area of the light-receiving openings 45c of the element 43. The total light shielding area) changes according to the storage level of the water 70 (the liquid level 71). Therefore, when the storage level (liquid level 71) of the water 70 is reduced in the third water storage stage, the aperture light shielding ratio in the third light emitting element 33 and the third light receiving element 43 is reduced, so that the output from the third light receiving element 43 is reduced. The value changes while gradually increasing as the output value F. That is, the output value F increases with increasing left shoulder. The above description is based on the premise that the light amounts of the emitted light and the incident light are uniform within the respective opening surfaces in the emission opening 35c of the third light emitting element 33 and the light receiving opening 45c of the third light receiving element 43. I have to.

  When further drainage is performed, the water storage level (liquid level 71) of the water 70 is in the bottom water storage stage in which the state where the level is lower than the optical axes of the third light emitting element 33 and the third light receiving element 43 continues. Therefore, in the bottom water storage stage, the output value has a certain output value G.

  As described above, since the output value at the light receiving unit 40 changes according to the storage level (liquid level 71) of the water 70 in the water supply tank 4, the water supply tank is based on the output value at the light receiving unit 40. 4, the water 70 storage level (liquid level 71) can be detected. That is, in this embodiment, as a storage level (liquid level 71) of the water 70 in the water supply tank 4, a high water storage stage (full water state), a first water storage stage, a middle water storage stage, and a second water storage stage in order from the top. The low water storage stage, the third water storage stage and the bottom water storage stage are detected.

  Based on the amount of light received by the light receiving unit 40, that is, the output value output from the light receiving unit 40, it is determined whether the water supply tank 4 is attached to or detached from the predetermined position of the main body casing 1a, and the water supply tank 4 The detection of the presence or absence of will be described.

  When the water supply tank 4 is removed from the predetermined position of the main body casing 1a, there is nothing that blocks the light emitted from the light emitting unit 30, so that the amount of light received by the light receiving unit 40 is maximized, and the water tank 4 is detached. The output value in the separated state is output as an output value H larger than the output value G.

  Therefore, if the output value H from the light receiving unit 40 is larger than the output value G, it is detected that the water supply tank 4 is detached from the predetermined position of the main casing 1a. Based on the amount of light received by the light receiving unit 40, that is, the output value (for example, output voltage) output from the light receiving unit 40, the container detection unit 60a has the water supply tank 4 attached to a predetermined position of the main casing 1a or detached. It is determined whether it is done. That is, an output value (for example, output voltage) output from the light receiving unit 40 is A / D converted by, for example, a microcomputer, and the converted digital value is compared with a certain predetermined value (output value G). The attachment or detachment of the water supply tank 4 is detected.

  In FIG. 10, the length in the horizontal axis direction at the bottom water storage stage is longer than that at the high water storage stage, middle water storage stage, and low water storage stage. This corresponds to the arrangement in the height direction of the light emitting elements 31, 32, 33 and the light receiving elements 41, 42, 43 in the water supply tank 4, as shown in FIG. That is, the distance between the optical path (opening) of the third light emitting element 33 and the third light receiving element 43 and the bottom surface portion 4d is such that the first light emitting element 31, the first light receiving element 41, the second light emitting element 32, and the second light receiving element 42. And between the optical paths of the second light emitting element 32 and the second light receiving element 42 and the third light emitting element 33 and the third light receiving element 43 (between the openings). It corresponds to that. Note that the distance between the optical paths of the three pairs of light-emitting elements and the light-receiving elements (between the openings) and the distance between the optical paths (openings) of the third light-emitting elements 33 and the third light-receiving elements 43 and the bottom surface portion 4d are any. Are substantially equal, the horizontal axis lengths in the high water storage stage, the middle water storage stage, the low water storage stage, and the bottom water storage stage are substantially equal.

  Further, as shown in FIG. 5, the emission openings 35 c of the light emitting elements 31, 32, 33 have the same opening width in the height direction, and the light receiving openings 45 c of the light receiving elements 41, 42, 43 are in the height direction. Have the same opening width. Therefore, the horizontal direction lengths in the first water storage stage, the second water storage stage, and the third water storage stage are substantially equal. In addition, the light quantity of an emitted light and incident light can be enlarged by enlarging the opening width of the height direction of the output opening 35c and the light-receiving opening 45c. By making use of this fact, the output value changes by increasing the respective opening widths in the height direction of the emission openings 35c and the light receiving openings 45c of the light emitting element and the light receiving element arranged where the output value is to be greatly changed. Can be increased.

  In FIG. 10, the place where the amount of light received by the light receiving unit 40 is the largest (output value H) is used to detect the attachment or detachment of the water supply tank 4, but the deterioration of the light emitting elements 31, 32, 33 and the optical properties. It can also be used for detecting abnormalities caused by contamination of the element (lens). If any abnormality occurs due to deterioration of the light emitting elements 31, 32, 33, dirt of the optical element (lens) in the light emitting unit 30 and the light receiving unit 40, the amount of light received by the light receiving unit 40 is greater than the amount of light received at the initial stage of operation. Will also decline.

  Therefore, the storage unit 22 stores the received light amount received by the light receiving unit 40 as the initial received light amount when the detachment of the water supply tank 4 is detected by the container detection unit 60a in the initial operation, and the received light amount decrease detection unit 60c The received light amount received by the light receiving unit 40 when the container detecting unit 60a detects the detachment of the water supply tank 4 and the initial received light amount stored in the storage unit 22 are compared, and the received light amount with respect to the initial received light amount. The abnormality can be detected by detecting whether or not the decrease is greater than a predetermined value. Then, the notification unit 23 can notify the user by notifying the decrease in the amount of received light when the decrease in the amount of received light with respect to the initial amount of received light is greater than a predetermined value. When any abnormality as described above is detected, the light emitting unit 30 can be automatically corrected by adjusting the current flowing through the light emitting elements 31, 32, 33, for example.

  FIG. 12 is a diagram illustrating that the level detection unit 60b is configured to have hysteresis so that the supply direction threshold value of the water 70 and the discharge direction threshold value are different. In FIG. 12, the left vertical axis indicates the storage level of the water 70 in the water supply tank 4.

  When the water 70 is drained from the water supply tank 4, the liquid level 71 slightly varies under the influence of the drainage. Similarly, when the water 70 is poured into the water supply tank 4, the liquid level 71 slightly fluctuates due to the influence of the water injection. Therefore, when the output value output from the light receiving unit 40 fluctuates, the detection result of the storage level of the water 70 in the water supply tank 4 may not be stabilized.

  Therefore, the level detection unit 60b is configured to have hysteresis so that the threshold value d in the supply direction of the water 70 and the threshold value e in the discharge direction are different. When the storage level (liquid level 71) of the water 70 in the water supply tank 4 moves from the bottom to the top (that is, when the water 70 is poured), the liquid level 71 of the water 70 exceeds the threshold d in the supply direction. Detect that a certain storage level has been reached. When the storage level (liquid level 71) of the water 70 in the water supply tank 4 moves from the top to the bottom (that is, the water 70 is drained), the level 70 of the water 70 falls below the threshold e in the discharge direction. Detect that a certain storage level has been reached. Since the level detection unit 60b has such a hysteresis, the output value output from the light receiving unit 40 is stabilized even if the liquid level 71 fluctuates slightly, and the storage level of the water 70 in the water supply tank 4 is stable. The detection result can be stabilized.

  Further, even if the liquid level 71 of the water 70 stored in the water supply tank 4 fluctuates, the light receiving unit 40 performs analog output corresponding to the amount of received light in order to stabilize the level detection by the level detecting unit 60b. The analog output may be subjected to filter processing or averaging processing.

  As described above, according to the present embodiment, the outgoing light restricting portion 35a allows the straight light to pass through but blocks the non-straight light, so that the interface (in the water supply tank 4 storing the water 70) ( The reflected light reflected by the (liquid level) 71 is reduced, and the reflected light is hardly received by the light receiving unit 40. Therefore, erroneous detection due to the reflected light can be prevented, and the storage level of the water 70 stored in the water supply tank 4 can be accurately detected.

[Second Embodiment]
Next, the transmissive optical coupling device 50 according to the second embodiment will be described with reference to FIGS. 7, 8, and 9. In the second embodiment, components having the same functions as the components in the first embodiment are given the same reference numerals, and redundant descriptions are omitted.

  FIG. 7 is a schematic cross-sectional view of the transmissive optical coupling device 50 according to the second embodiment and the water supply tank 4 in which the device 50 is installed. FIG. 8 is a schematic longitudinal sectional view of the corner portion 4f of the water supply tank 4 in which the transmissive optical coupling device 50 shown in FIG. 7 is installed as viewed from the light emitting portion 30 side. FIG. 9 is a schematic longitudinal sectional view in a cross section including the light emitting unit 30 and the light receiving unit 40 in the corner portion 4f of the water supply tank 4 in which the transmission type optical coupling device 50 shown in FIG.

  As shown in FIG. 9, each light emitting element 31, 32, 33 of the light emitting unit 30 does not include the above-described outgoing light restricting portion 35 a and other outgoing light restricting portions 35 b, and the light emitting portion 30 has a certain size. The light is emitted at the emission directivity angle P. The light receiving elements 41, 42, and 43 of the light receiving unit 40 also do not include the light receiving restriction unit 45a and the other light receiving restriction units 45b described above, and the light receiving unit 40 receives light at a certain light reception directivity angle Q. To do. In addition, the light emitting unit 30 is disposed on the light emitting side wall portion 4b via the light emitting portion spacer 53, and the light receiving portion 40 is disposed on the light receiving side sidewall portion 4c via the light receiving portion spacer 54.

  In the first embodiment described above, the central light La is used as the straight light emitted from the light emitting unit 30 so that the light emitted from the light emitting unit 30 forms an angle with respect to the light emitting side wall 4b. The light emitting unit 30 is disposed obliquely. The center light La of the light emitted from the light emitting unit 30 is optically coupled to the light receiving unit 40. According to the said structure, in the light emission part 30, the edge part on the opposite side to the light emission side side wall part 4b protrudes, the size of the transmissive | pervious optical coupling device 50 becomes large, and an attachment space becomes large.

  The light emitted from the light emitting unit 30 generally has a certain light emission directivity angle P. Therefore, in the transmissive optical coupling device 50 according to the second embodiment, the light emitting elements 31, 32, and 33 having a certain light emission directivity angle P are used to out of the light emitted from the light emitting unit 30. The light emitting edge light Lp having the light emission directivity angle P is configured to be optically coupled to the light receiving unit 40.

  Of the light emitted from the light emitting unit 30, the light emitting edge light Lp having the light emitting directivity angle P and the light receiving edge portion Lq having the light receiving directivity angle Q of the light received by the light receiving unit 40 are optically coupled. Has been. For the optical coupling, for example, the light emitting unit 30 is arranged so that the optical axis light emitted from the light emitting unit 30 is perpendicular to the light emitting side wall 4b and is received by the light receiving unit 40. The light receiving part 40 is arranged so that the optical axis light is perpendicular to the light receiving side wall part 4c. In the light emitting unit 30, the protrusion of the end opposite to the light emitting side wall 4 b is suppressed, and in the light receiving unit 40, the protrusion of the end opposite to the light receiving side wall 4 c is suppressed, thereby transmitting light. The size of the coupling device 50 is reduced, and the mounting space is reduced.

  Therefore, since the transmissive optical coupling device 50 does not include the outgoing light restricting portion 35a, the other outgoing light restricting portion 35b, the light receiving restricting portion 45a, and the other light receiving restricting portion 45b, the configurations of the light emitting portion 30 and the light receiving portion 40 are configured. It can be simplified. And since the protrusion of the light emission part 30 and the light-receiving part 40 decreases, the installation space when installing the transmissive | pervious optical coupling device 50 in the heating cooker 1 becomes small, and the dead space accompanying this installation becomes small.

  Note that the arrangement of the light emitting unit 30 with respect to the light emitting side wall 4b is not limited to an arrangement with a right angle, and may be an arrangement inclined in a direction facing the light receiving unit 40. In addition, the arrangement of the light receiving unit 40 with respect to the light receiving side wall 4c is not limited to the arrangement at a right angle, and may be an arrangement inclined in a direction facing the light emitting unit 30.

  Although a specific embodiment of the present invention has been described, the present invention is not limited to the above-described embodiment, and can be implemented with various modifications or appropriate combinations within the scope of the present invention. .

  In the above embodiment, the light emitting unit 30 and the light receiving unit 40 use near infrared light for detection of the storage level, but light other than near infrared light (for example, visible light) may be used.

  Moreover, in the said embodiment, although the output value from the light-receiving part 40 was a voltage, it is not restricted to this, For example, an electric current may be sufficient.

  Moreover, in the said embodiment, although the water supply tank 4 as a container was comprised from the transparent member, it may be comprised from the translucent member and should just have a light transmittance. Similarly, the water 70 as a liquid is transparent, but may be a translucent liquid as long as it has optical transparency. In particular, the greater the difference in refractive index between the liquid 70 and the gas 74, such as water and air, the more effective.

  Moreover, in the said embodiment, although the storage level of the water 70 is detected, you may detect the storage level (liquid level) of the liquids 70, such as a well-known washing | cleaning liquid containing a citric acid solution. Furthermore, it goes without saying that the storage level (liquid level) can be detected even in a liquid 70 having a very small or low light transmittance, such as ink.

  In the above-described embodiment, the container detection unit 60a detects the attachment or detachment of the water supply tank 4 by the transmission type optical coupling device 50 and software. However, hardware (for example, a mechanical (mechanical) switch provided separately) ) May detect whether the water supply tank 4 is attached or detached.

  Moreover, in the said embodiment, although the level detection part 60b detects the storage level based on the addition value which added the several output value (photocurrent value), it is separately for every pair of light emitting element and light receiving element. Alternatively, the storage level may be detected by independently driving and comparing each output value with a value corresponding to the storage level by a comparator.

  Although the light emitted from the light emitting unit 30 is emitted substantially horizontally and the light emitting unit 30 and the light receiving unit 40 are positioned at substantially the same level, the present invention is not limited thereto. For example, the light emitted from the light emitting unit 30 may be emitted obliquely upward or obliquely downward with respect to the horizontal plane, and the light emitting unit 30 and the light receiving unit 40 may be positioned at different levels. Further, the storage level (liquid level) of the liquid 70 can be freely set by arranging the pair of light emitting elements and light receiving elements at positions where the storage level (liquid level) of the liquid 70 is desired to be detected.

  Moreover, in the said embodiment, in order to detect the storage level of the water 70 in the water supply tank 4, three pairs of light emitting elements 31, 32, and 33 and light receiving elements 41, 42, and 43 are used. A light emitting element and a light receiving element, two pairs of light emitting elements and light receiving elements, four or more pairs of light emitting elements and light receiving elements may be used.

[Third Embodiment]
Further, in the electrical apparatus 1 that generates electromagnetic noise such as a microwave oven, in order to reduce noise entering the light emitting element and the light receiving element, the outgoing light restricting portion 35a, the other outgoing light restricting portion 35b, and the light receiving restricting portion 45a. The other light receiving regulation part 45b may be made of a conductive material and grounded.

[Fourth Embodiment]
Next, a transmissive optical coupling device 50 according to a fourth embodiment will be described with reference to FIGS. 13 and 14. In the fourth embodiment, components having the same functions as the components in the first embodiment are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 13 is a schematic longitudinal sectional view showing a main part of a transmissive optical coupling device 50 according to the fourth embodiment. FIG. 14 is a diagram for explaining the relationship between the storage level of water 70 in the water supply tank 4 and the output value at the light receiving unit 40 in the transmissive optical coupling device 50 shown in FIG.

  As shown in FIG. 13, the bottom surface portion 4 d of the corner portion 4 f of the water supply tank 4 is formed with an inclined portion 4 e whose outer portion is cut out obliquely. A pair of third light emitting element 33 and third light receiving element 43 is disposed at a position corresponding to the inclined portion 4e. Above the third light emitting element 33 and the third light receiving element 43, a pair of the second light emitting element 32 and the second light receiving element 42, and the pair of the first light emitting element 31 and the first light receiving element 41 are arranged in order from the bottom. Although not shown, the pair of the first light emitting element 31 and the first light receiving element 41 is not shown in FIG.

  The light emitted from the third light emitting element 33 passes through the inside of the water supply tank 4 including the inclined portion 4e and is received by the third light receiving element 43, but the optical path length when passing through the inside of the water supply tank 4 is inclined. The outer portion cut out by the portion 4e is shorter than other portions (high water storage stage, middle water storage stage, etc.). As the optical path length in the water supply tank 4 storing the water 70 is shorter, the attenuation of light by the water 70 is reduced, so that the amount of light received by the third light receiving element 43 is increased. Further, since the notch by the inclined portion 4e is present in the bottom surface portion 4d, the internal volume on the bottom surface portion 4d side is smaller than the internal volume of other portions (high water storage stage, medium water storage stage, etc.). ing. Due to these factors, when the volume of the water 70 stored on the bottom surface portion 4d side of the water supply tank 4 changes slightly, the amount of light received by the third light receiving element 43 changes greatly, and the change in output value also increases. As a result, as shown in FIG. 14, the slope of the output value F becomes larger than the slope of the output value D by the sloped part 4 e formed on the bottom face part 4 d side, and the output value F is likely to change. Therefore, by utilizing the fact that the output value F on the bottom surface portion 4d side is likely to change, when discharging the water 70 from the water supply tank 4, the change in the storage level on the bottom surface portion 4d side can be detected in more detail. The amount of remaining water before the water 70 disappears in the tank 4 can be detected in more detail.

  In the first embodiment to the fourth embodiment, the heating cooker 1 (specifically, the steam cooker) has been described as the electric device. For example, the jar rice cooker having the moisture-retaining water supply tank and the liquid detergent tank are provided. Washing machines, vacuum cleaners with water filter tanks, refrigerators with ice-making water tanks, air purifiers and ion generators with humidifying water tanks, coffee makers with water tanks, irons with steam generating tanks, etc. It can be applied to various electric devices 1 having a container 4 for storing the liquid 70 to be used. In addition to the above applications, various electric appliances having a container 4 for recovering discharged liquid 70 such as an air cleaner having a dehumidifying recovery tank, an ion generator, and a tableware dryer having a water droplet recovery tank. It can also be applied to the device 1.

As described above, the transmission optical coupling device 50 of the present invention is
A transmission type optical coupling device 50 capable of detecting a storage level of a light-transmitting liquid 70 stored in a light-transmitting container 4,
A light emitting unit 30 that emits light toward the side wall 4b of the container 4;
A light receiving unit 40 that receives light emitted from the light emitting unit 30 and transmitted through the container 4;
A level detection unit 60b for detecting the storage level of the liquid 70 stored in the container 4 based on the amount of light received by the light receiving unit 40;
Among the light emitted from the light emitting unit 30, the straight traveling light that travels straight in the direction of the light receiving unit 40 is allowed to pass, while the liquid 70 passes through the liquid 70 and contacts the liquid 70. And an outgoing light restricting portion 35a that shields non-straight light that can be reflected light at the interface 71 with the light source 74.

  According to the above configuration, the straight light can pass through the outgoing light restricting portion 35a, but the non-straight light is shielded, so that the liquid 70 is transmitted (the liquid surface 71 is above the light receiving / emitting optical axis). However, the reflected light reflected at the interface 71 between the liquid 70 and the gas 74 is reduced, and the reflected light is hardly received by the light receiving unit 40. For this reason, the erroneous detection resulting from reflected light can be prevented, and the storage level of the liquid 70 stored in the container 4 can be detected accurately.

  Preferably, in the transmissive optical coupling device 50, the outgoing light restricting portion is an upper light shielding portion 35a provided on the upper side of the light emitting portion 30.

  According to the above configuration, the non-straight light emitted from the light emitting unit 30 in the direction of the interface 71 between the liquid 70 and the gas 74 is shielded by the upper light shielding unit 35 a, and thus the liquid level reflected at the interface 71 between the liquid 70 and the gas 74. Since the reflected light is reduced and the liquid surface reflected light is less likely to be received by the light receiving unit 40, erroneous detection due to the liquid surface reflected light can be prevented.

  Preferably, the transmissive optical coupling device 50 includes a lower light-shielding portion 35b provided on the lower side of the light emitting portion 30 as another outgoing light restricting portion.

  According to the above configuration, since the non-straight light emitted in the direction of the bottom surface portion 4d of the container 4 is shielded by the lower light shielding portion 35b, the bottom surface reflected light reflected by the bottom surface portion 4d of the container 4 storing the liquid 70 is reflected. Since the bottom surface reflected light is less likely to be received by the light receiving unit 40, erroneous detection due to the bottom surface reflected light can be prevented.

Preferably, the transmissive optical coupling device 50 further includes a container detection unit 60a for detecting that the container 4 is attached to or detached from a predetermined place,
The container detector 60a detects the detachment of the container 4 when the amount of light received by the light receiver 40 is larger than the amount of light received when the storage level of the liquid 70 is detected.

  According to the above configuration, the attachment or detachment of the container 4 can be detected by the change in the amount of light received by the light receiving unit 40.

  Preferably, in the transmissive optical coupling device 50, the level detection unit 60b has hysteresis.

  According to the above configuration, even when the interface 71 between the liquid 70 and the gas 74 varies due to drainage or water injection, level detection by the level detection unit 60b can be stabilized.

  Preferably, in the transmissive optical coupling device 50, the light receiving unit 40 performs an analog output corresponding to the amount of received light, and performs a filtering process or an averaging process on the analog output.

  According to the above configuration, even when the interface 71 between the liquid 70 and the gas 74 varies due to drainage or water injection, level detection by the level detection unit 60b can be stabilized.

  Moreover, the electric apparatus 1 of the present invention includes the above-described transmission type optical coupling device 50.

  According to the above configuration, by arranging the light emitting unit 30 and the light receiving unit 40 at a height to be detected, it is possible to adjust the output to change depending on the storage level of the liquid 70 to be detected. The storage level of the liquid 70 stored in the container 4 can be detected reliably and stably.

Preferably, in the electric device 1, the light emitting unit 30 and the light receiving unit 40 are disposed on adjacent side wall parts 4 b and 4 c in the container 4, respectively, and light emitted from the light emitting unit 30 is the electric The transmissive optical coupling device 50 is configured to cross the corner portion 4f of the container 4 attached to the device 1,
The light emitting unit 30 and the light receiving unit 40 are disposed opposite to each other and optically coupled.

  According to the said structure, compared with the case where the light emission part 30 and the light-receiving part 40 are each installed in the side wall part which opposes in the container 4, the optical path length from the light emission part 30 to the light-receiving part 40 becomes short, and an optical axis of It is possible to prevent a decrease in optical connectivity due to the shift. Further, according to the above configuration, depending on the presence or absence of the liquid 70 in the container 4, the optical characteristics such as light refraction and total reflection are different, and the output from the light receiving unit 40 is different. As a result, the presence or absence of the liquid 70 at a certain storage level (liquid level) can be effectively determined.

The electrical device 1 of the present invention is
An electrical apparatus 1 including a transmissive optical coupling device 50 capable of detecting a storage level of a light-transmitting liquid 70 stored in a light-transmitting container 4,
A light emitting unit 30 that emits light toward the side wall 4b of the container 4;
A light receiving unit 40 that receives light emitted from the light emitting unit 30 and transmitted through the container 4;
A level detection unit 60b for detecting the storage level of the liquid 70 stored in the container 4 based on the amount of light received by the light receiving unit 40;
The container 4 in which the light emitting unit 30 and the light receiving unit 40 are respectively disposed on adjacent side wall parts 4 b and 4 c in the container 4, and light emitted from the light emitting unit 30 is attached to the electric device 1. The transmissive optical coupling device 50 is configured to cross the corner portion 4f of
Of the light emitted from the light emitting unit 30, the light emitting edge light Lp having the light emitting directivity angle P and the light receiving edge portion Lq having the light receiving directivity angle Q of the light received by the light receiving unit 40 are optically coupled. It is characterized by.

  According to the above configuration, since the transmissive optical coupling device 50 does not include the outgoing light restricting portion 35a, the other outgoing light restricting portion 35b, the light receiving restricting portion 45a, and the other light receiving restricting portion 45b, the light emitting portion 30 and the light receiving portion. Forty configurations can be simplified. And since the protrusion of the light emission part 30 and the light-receiving part 40 decreases, the installation space when installing the transmissive | pervious optical coupling device 50 in the electric equipment 1 becomes small, and the dead space accompanying this installation becomes small.

Preferably, in the electric device 1, the light emitting unit 30 and the light receiving unit 40 include a plurality of light emitting elements 31, 32, 33 and a plurality of light receiving elements 41, 42, 43 arranged in the depth direction of the container 4. Each with
The light emitting unit 30 causes all of the plurality of light emitting elements 31, 32, and 33 to emit light, and the light receiving unit 40 adds the respective photocurrent values generated by the plurality of light receiving elements 41, 42, and 43. The output value corresponding to the added value is output.

  According to the above configuration, the processing circuit can be simplified as compared with the case where the plurality of light emitting elements 31, 32, 33 and the plurality of light receiving elements 41, 42, 43 are individually driven and output.

Preferably, in the electrical device 1, a container detection unit 60a that detects that the container 4 is attached or detached at a predetermined location;
A storage unit 22 for storing the received light amount received by the light receiving unit 40 when the container detection unit 60a detects the detachment of the container 4 in the initial stage of operation as an initial received light amount;
The light receiving amount received by the light receiving unit 40 when the container detecting unit 60a detects the detachment of the container 4 and the initial light receiving amount stored in the storage unit 22 are compared, and the initial light receiving A received light amount decrease detection unit 60c for detecting whether or not the decrease in the received light amount with respect to the amount is greater than a predetermined value;
And a notification unit for notifying the decrease in the amount of received light when the decrease in the amount of received light with respect to the initial amount of received light is greater than a predetermined value.

  According to the above configuration, since a notification is given when the decrease in the amount of received light is greater than a predetermined value compared to the initial stage of operation, the light emitting unit 30 and the light receiving unit 40 are deteriorated or provided in the light emitting unit 30 and the light receiving unit 40. It is possible to detect dirt on the lens.

1 Heating cooker (electric equipment)
1a Body casing 2 Heating chamber 4 Water supply tank (container)
4a Lid 4b Light-emitting side wall 4c Light-receiving side wall 4d Bottom 4f Corner 4e Inclined 22 Storage 23 Notification unit 30 Light-emitting unit 31 First light-emitting element 32 Second light-emitting element 33 Third light-emitting element 34 Light-emitting substrate 35a Shading part (emitted light regulation part)
35b Lower light shielding part (other outgoing light regulating part)
35c Outgoing aperture 35d Connection light shielding part 40 Light receiving part 41 First light receiving element 42 Second light receiving element 43 Third light receiving element 44 Light receiving substrate 45a Upper light shielding part (light receiving restriction part)
45b Lower light shielding part (other light receiving regulation part)
45c Light receiving opening 50 Transmission type optical coupling device 52 Support body 53 Light emitting portion spacer 54 Light receiving portion spacer 60 Control device 60a Container detecting portion 60b Level detecting portion 60c Light receiving amount decrease detecting portion 70 Water (liquid)
71 Liquid level (interface)
72 Bottom interface (interface)
74 Air (gas)
P Light emitting directivity angle Q Light receiving directivity angle La Center light Lp Light emitting edge light Lq Light receiving edge portion

Claims (11)

A transmission type optical coupling device capable of detecting a storage level of a liquid having optical transparency stored in a container having optical transparency,
A light emitting part for emitting light toward the side wall part of the container;
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container;
Based on the amount of light received by the light receiving unit, a level detection unit that detects a storage level of the liquid stored in the container;
Among the light emitted from the light emitting part, the straight light emitted straightly in the direction of the light receiving part is allowed to pass, while being reflected at the interface between the liquid and the gas in contact with the liquid. A transmission type optical coupling device comprising: an outgoing light restricting unit that blocks non-straight light that can be reflected light.   2. The transmissive optical coupling device according to claim 1, wherein the outgoing light restricting portion is an upper light shielding portion provided on an upper side of the light emitting portion.   The transmissive optical coupling device according to claim 1, further comprising a lower light-shielding portion provided below the light-emitting portion as another outgoing light regulating portion. A container detection unit for detecting that the container is attached to or detached from the predetermined place;
The container detection unit detects the detachment of the container when the amount of light received by the light receiving unit is larger than the amount of light received when the storage level of the liquid is detected. The transmissive optical coupling device according to claim 3.   The transmissive optical coupling device according to claim 1, wherein the level detection unit has hysteresis.   The said light-receiving part performs the analog output according to the light reception amount, and performs a filter process or an averaging process with respect to this analog output, The Claim 1 characterized by the above-mentioned. Transmission type optical coupling device.   An electric apparatus comprising the transmissive optical coupling device according to any one of claims 1 to 6. The light emitting part and the light receiving part are respectively disposed on adjacent side wall parts of the container, and the light emitted from the light emitting part is transmitted through the corner part of the container mounted on the electric device. Type optical coupling device is configured,
The electric device according to claim 7, wherein the light emitting unit and the light receiving unit are disposed to face each other and optically coupled. An electrical apparatus including a transmissive optical coupling device capable of detecting a storage level of a light-transmitting liquid stored in a light-transmitting container,
A light emitting part for emitting light toward the side wall part of the container;
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container;
A level detection unit that detects a storage level of the liquid stored in the container based on the amount of light received by the light receiving unit;
The light emitting part and the light receiving part are respectively disposed on adjacent side wall parts of the container, and the light emitted from the light emitting part is transmitted through the corner part of the container mounted on the electric device. Type optical coupling device is configured,
An electric device characterized in that light emission edge light having a light emission directivity angle out of light emitted from the light emission portion and a light reception edge portion having a light reception directivity angle of light received by the light reception portion are optically coupled. . The light emitting part and the light receiving part respectively have a plurality of light emitting elements and a plurality of light receiving elements arranged in the depth direction of the container,
The light emitting unit emits all of the plurality of light emitting elements, and the light receiving unit outputs an output value corresponding to an added value obtained by adding the photocurrent values generated by the plurality of light receiving elements. The electrical device according to claim 7, wherein the electrical device is characterized. A container detection unit for detecting that the container is attached to or detached from the predetermined place;
A storage unit that stores the received light amount received by the light receiving unit as an initial received light amount when detachment of the container is detected by the container detection unit in an initial operation;
The received light amount received by the light receiving unit when the container detecting unit detects the detachment of the container and the initial received light amount stored in the storage unit, and the received light amount with respect to the initial received light amount A received light amount decrease detection unit for detecting whether or not the decrease in the amount is greater than a predetermined value;
The electric device according to claim 7, further comprising a notification unit that notifies the decrease in the amount of received light when the decrease in the amount of received light with respect to the initial amount of received light is greater than a predetermined value. .

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