JP6778034B2 - Transmission type optical coupling device and electrical equipment equipped with the device - Google Patents

Description

The present invention relates to a transmissive light coupling device and an electrical device including the device, and more particularly, a transmissive light coupling device for detecting a storage level of a light transmissive liquid stored in a light transmissive container and a transmissive light coupling device. The present invention relates to an electric device including the device.

Patent Document 1 is composed of a light emitter arranged at a position avoiding the center of the inner wall of the drip tube and a light receiver arranged at a position where light can be received when the chemical solution of the drip tube is not on the light emitting line. The present invention discloses a liquid level detection device including a detector fixed to a drip tube.

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

In Patent Document 3, a light emitting means and a light receiving means are arranged so as to sandwich a part of a container or a liquid chamber communicating with the container, and the transmitted optical axis of the container or the inner surface of the liquid chamber is arranged in the liquid level detecting means by changing the amount of transmitted light. Disclosed is a liquid level detecting means for forming a portion crossed by a member having a high wettability.

Japanese Unexamined Patent Publication No. 02-295567 Japanese Unexamined Patent Publication No. 61-270881 Japanese Unexamined Patent Publication No. 05-340791

In the liquid level detection device of Patent Document 1, the liquid level is detected by utilizing the refraction action of the drip tube and the chemical solution, and the receiver is in a position where light cannot be received or can be received depending on the presence or absence of the chemical solution. As such, it is necessary to adjust the refraction action of the drip tube and the drug solution.

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

In the liquid level detecting 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 the ink having low light transmission, and the height of the ink liquid level is detected by the change in the amount of transmitted light. It utilizes the light-shielding property of ink, which has very low light transmission. Therefore, it is inappropriate to use a light-transmitting liquid as the target liquid in the liquid level detecting means of Patent Document 3.

As described above, Patent Document 1 and Patent Document 2 utilize the refraction action of the container to be measured and the liquid, and Patent Document 3 utilizes the change in the amount of transmitted light. However, in Patent Document 3, the light-shielding property of the ink is utilized, and there is a possibility of erroneously detecting that the ink has light transmission property.

By the way, when the liquid level of a liquid having light transmission is detected by a change in the amount of transmitted light, the light emitted from the light emitting portion is directly received by the light receiving portion, that is, the direct light is received by the light receiving portion. , Preferable in terms of accurate storage level detection. However, in reality, there is an interface in the container that stores the liquid because the refractive index differs between the container and the liquid. For example, there are a liquid level and a bottom interface between the air and the liquid and between the bottom surface of the container and the liquid, respectively. Then, depending on the angle of incidence with respect to the interface, the light incident on the interface is not transmitted but reflected at the interface. Therefore, the reflected light, that is, the indirect light reflected at the liquid surface or the bottom interface 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 storage level of the liquid, and there is a risk of erroneous detection.

Therefore, the technical problem to be solved by the present invention is to prevent the reflected light 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 portion so that the storage level is accurate. It is an object of the present invention to provide a transmissive optical coupling device for detecting a device and an electric device including the device.

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

A transmissive optical coupling device capable of detecting the storage level of a light-transmitting liquid stored in a light-transmitting container.
A light emitting portion that emits light toward the side wall portion of the container, and a light emitting portion.
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container, and a light receiving unit.
A level detection unit that detects the storage level of the liquid stored in the container based on the amount of light received by the light receiving unit.
Of the light emitted from the light emitting portion, the straight light emitted in the direction of the light receiving portion can pass through, while being transmitted through the liquid and reflected at the interface between the liquid and the gas in contact with the liquid. It is characterized by including an emitted light regulating unit that blocks non-straight light that can be reflected light.

Preferably, the emitted light restricting portion is an upper shading portion provided above the light emitting portion.

Preferably, as another emission light regulating unit, it has a lower shading unit provided below the light emitting unit.

Preferably, it further comprises a container detector for detecting that the container is attached or detached from a predetermined location.
The container detection unit detects the detachment of the container when the light receiving amount of the light receiving unit is larger than the light receiving amount when detecting the storage level of the liquid.

Preferably, the level detector has hysteresis.

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

Further, the electric device of the present invention includes the transmission type optical coupling device according to any one of claims 1 to 5.

Preferably, the light emitting portion and the light receiving portion are arranged on adjacent side wall portions of the container so that the light emitted from the light emitting portion crosses the corner portion of the container mounted on the electric device. The transmissive optical coupling device is configured in
The light emitting portion and the light receiving portion are arranged so as to face each other and optically coupled.

According to the present invention, an electric device including a transmissive optical coupling device capable of detecting the storage level of a light-transmitting liquid stored in a light-transmitting container.
A light emitting portion that emits light toward the side wall portion of the container, and a light emitting portion.
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container, and a light receiving unit.
A level detection unit for detecting the storage level of the liquid stored in the container based on the amount of light received by the light receiving unit is provided.
The light emitting portion and the light receiving portion are respectively arranged on adjacent side wall portions of the container, and the light emitted from the light emitting portion is transmitted so as to cross the corner portion of the container mounted on the electric device. A type optical coupling device is configured
Provided is an electric device in which a light emitting edge portion having a light emitting directivity angle among the light emitted from the light emitting unit and a light receiving edge portion having a light receiving directivity angle of the light received by the light receiving unit are optically coupled.

Preferably, the light emitting unit and the light receiving unit have a plurality of light emitting elements and a plurality of light receiving elements arranged in the depth direction of the container, respectively.
All of the plurality of light emitting elements in the light emitting unit are made to emit light, and the light receiving unit outputs an output value corresponding to an added 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 in a predetermined place and
A storage unit that stores the amount of light received by the light receiving unit as the initial amount of light received when the container detection unit detects the detachment of the container at the initial stage of operation.
The amount of light received by the light receiving unit when the container detection unit detects the detachment of the container is compared with the amount of initial light received stored in the storage unit, and the light received with respect to the initial amount of light received is compared. A light receiving amount decrease detection unit that detects whether or not the amount decrease is larger than a predetermined value,
When the decrease in the received light amount with respect to the initial received amount is larger than a predetermined value, the notification unit is provided to notify the decrease in the received light amount.

According to the transmissive light coupling device of the present invention, the light emitted without going straight in the direction of the light receiving portion is blocked by the emitted light regulating portion, so that the reflected light reflected at the interface in the container in which the liquid is stored is reduced. Therefore, it becomes difficult for the reflected light 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 accurately detect the storage level of the liquid stored in the container.

The schematic front view of the cooking apparatus provided with the transmission type light coupling apparatus which concerns on 1st Embodiment of this invention. The schematic vertical sectional view of the cooking apparatus shown in FIG. The control block diagram of the cooking apparatus shown in FIG. The schematic cross-sectional view of the said transmission type optical coupling apparatus and the container in which the apparatus is installed. FIG. 6 is a schematic vertical sectional view of the transmission type optical coupling device shown in FIG. The schematic explanatory view of the light emitting part in a transmission type light coupling apparatus. FIG. 3 is a schematic cross-sectional view of a transmissive optical coupling device according to a second embodiment of the present invention and a container in which the device is installed. FIG. 7 is a schematic vertical sectional view of a corner portion of a container in which the transmissive optical coupling device shown in FIG. 7 is installed, as viewed from the light emitting portion side. FIG. 7 is a schematic vertical cross-sectional view of a corner portion of a container in which the transmissive optical coupling device shown in FIG. 7 is installed, in a cross section including a light emitting portion and a light receiving portion. The figure explaining the relationship between the storage level of the liquid in a container, and the output value in a light receiving part. A circuit diagram when adding photocurrents generated by a plurality of light receiving elements. The figure explaining that the level detection part is configured to have hysteresis so that a threshold value in a liquid supply direction and a threshold value in a liquid discharge direction are different. The schematic vertical sectional view which shows the main part of the transmission type optical coupling apparatus which concerns on 4th Embodiment. It is a figure explaining the relationship between the storage level of the liquid in a container and the output value in a light receiving part in the transmission type optical coupling apparatus shown in FIG.

Hereinafter, the cooking device 1 provided with the transmission type light coupling device 50 according to the first embodiment of the present invention will be described with reference to the drawings. It should be noted that this embodiment is merely an example, and the present invention is not limited to this embodiment.

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

As shown in FIG. 1, the cooking cooker 1 has a rectangular parallelepiped main body casing 1a, a heating chamber 2 provided in the main body casing 1a, and a front side of the main body casing 1a with a lower side as an axis. It includes a rotatably attached door 3 and a water supply tank 4 housed in a main body casing 1a and detachably attached. The water supply tank 4 is an example of a container for storing water 70 as a light-transparent liquid.

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

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

The door 3 opens and closes the opening 2a 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). Further, the door 3 has a handle 7 located 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 has a color liquid crystal display unit 9, a button group 10, and a dial 11. The button group 10 includes a cancel button that is pressed when the heating is stopped in the middle or when the operation is restarted, and a warming start button that is pressed when the microwave oven is automatically heated or another heating is started. And so on. Further, the dial 11 is used when adjusting the output of the range.

When the water supply tank 4 is attached to the main body casing 1a, the water supply tank 4 is located below the right side 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-transmitting 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 side wall portion 4b, a light receiving side side wall portion 4c, two other side wall portions, and a bottom surface portion 4d. It is composed of a housing having a. An inclined portion 4e inclined upward toward the light receiving side side wall portion 4c is formed on the bottom surface portion 4d on the light receiving side side wall portion 4c side. A corner portion 4f is formed in the vicinity of the portion where the light emitting side side wall portion 4b and the light receiving side side wall portion 4c, which are adjacent side wall portions, intersect with each other.

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 4d of the water supply tank 4 in contact with the water 70.

FIG. 2 is a schematic view showing a cross section of the cooking utensil 1 cut in a vertical plane parallel to the front-rear direction.

A steam generator 12 is installed inside the main body casing 1a and outside the heating chamber 2. The steam generator 12 heats the water 70 from the water supply tank 4 with a heater to convert it into steam and supplies it into the heating chamber 2, or further heats the steam with a heater to convert it into superheated steam and supplies it into the heating chamber 2. Or something. At this time, water is supplied from the water supply tank 4 to the steam generator 12 by the water supply pump 13 (shown in FIG. 3). The superheated steam is steam that has reached a temperature exceeding 100 ° C.

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

The heating chamber 2 is formed so as to accommodate a tray 16 on which the object 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 20 to be heated on the tray 16 is heated by steam or superheated steam from the steam generator 12, or by radiant heat of the upper heater 17 and the lower heater 18. Further, there is a top wall of the heating chamber 2 below the upper heater 17, a bottom wall of the heating chamber 2 above the lower heater 18, and 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.

Further, the cooking cooker 1 includes a transmission type 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 1a, that is, on the side opposite to the take-out side of the water supply tank 4.

The transmission type optical coupling device 50 includes a light emitting unit 30 that emits light toward the light emitting side 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. A support 52 for supporting the light emitting unit 30 and the light receiving unit 40 and attaching the light emitting unit 30 to the main body casing 1a is provided.

The light emitting unit 30 has at least one light emitting element that emits near-infrared light, and 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 31 and the second light emitting element. It has a light emitting element 32 and a third light emitting element 33. The light emitting unit 30 is configured to emit light substantially horizontally toward the light emitting side side wall portion 4b of the water supply tank 4. Each of the light emitting elements 31, 32, 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 has at least one light receiving element corresponding to the light emitting element of the light emitting unit 30, and in this embodiment, the three light receiving elements arranged in the depth direction of the water supply tank 4, that is, the first light receiving element 41. It has a second light receiving element 42 and a third light receiving element 43. The light receiving unit 40 receives light emitted from the light emitting unit 30 substantially horizontally and transmitted substantially horizontally through the water supply tank 4. 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) according to the amount of light received by each of the light receiving elements 41, 42, 43.

FIG. 3 is a control block diagram of the cooking device 1.

The cooking 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 steam 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 steam generator 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 transmission type optical coupling device 50. The amount of light received by the light receiving unit 40 is determined by the water tank 4 when the water tank 4 is not mounted or when the water tank 4 is mounted and the water 70 is not stored in the water tank 4. When the water 70 is installed and stored in the water supply tank 4, the size increases in this order.

The storage unit 22 stores various control programs for exchanging various information with the control device 60. Then, the storage unit 22 stores the amount of light received by the light receiving unit 40 as the initial amount of light received when the container detection unit 60a detects the detachment of the water supply tank 4 at the initial stage of operation. The storage unit 22 is composed of a ROM (Read Only Memory), a RAM (Random Access Memory), and the like.

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

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

The container detection unit 60a determines whether the water supply tank 4 is attached to or detached from the main body 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 or not the water 70 is at 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, and supplies water. The storage level of the water 70 stored in the tank 4 is detected.

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

The container detection unit 60a, the level detection unit 60b, and the light receiving amount decrease detection unit 60c are each composed of software.

An emission light regulation unit 35a and another emission light regulation unit 35b are provided between the light emitting unit 30 and the light emitting side side wall portion 4b of the water supply tank 4. The emission light regulation unit 35a and the other emission light regulation unit 35b are incorporated as a part of the light emitting unit 30, and emit light so as to cover the light emitting side of the light emitting elements 31, 32, 33 except for the portion where the emitted light is emitted. It is arranged in the vicinity of the elements 31, 32, 33. The emission light regulation unit 35a and the other emission light regulation unit 35b may be arranged on the side of the light emitting side side wall portion 4b or on the intermediate portion between the light emitting unit 30 and the light emitting side side wall portion 4b.

On the exit side of the light emitting elements 31, 32, 33, the upper light-shielding portion 35a as the emission light regulation unit, the lower light-shielding portion 35b as the other emission light regulation unit, and the light-receiving unit 40 are emitted straight ahead. An exit opening 35c that allows straight light to pass through is provided. The upper light-shielding portion 35a shields non-straight light that can be reflected light that passes through the water 70 and is reflected at the liquid surface 71 (interface) without going straight in the direction of the light receiving portion 40. The lower light-shielding portion 35b shields non-straight light that can be reflected light that passes through the water 70 and is reflected at the bottom interface 72 (interface) without going straight in the direction of the light receiving portion 40. Therefore, the emitted light regulating unit 35a and the other emitted light regulating unit 35b allow the straight light emitted to travel straight in the direction of the light receiving unit 40 to pass through, while the liquid level does not travel straight in the direction of the light receiving unit 40. Non-straight light that can be reflected light reflected at 71 (interface) and bottom interface 72 (interface) is blocked.

The upper light-shielding unit 35a is provided on the upper side of the light-emitting unit 30 to block light emitted upward. That is, it is emitted above the optical axis of the light emitting unit 30, and the liquid level 71 of the water 70 is emitted toward the liquid level 71 of the water 70 stored in the water supply tank 4 above the optical axis of the light emitting unit 30. It blocks the light. When the light emitting unit 30 has 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 emitting unit 35a is located above each of the light emitting elements 31, 32, 33, respectively. It is provided. The upper light-shielding portion 35a provided on 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 35a provided on 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 light-shielding portion 35a can prevent the occurrence of so-called crosstalk between the unpaired light emitting element and the light receiving element.

The lower light-shielding unit 35b is provided below the light-emitting unit 30 to block light emitted downward. That is, the liquid level 71 of the water 70 is emitted below the optical axis of the light emitting unit 30, and the bottom surface portion 4d direction, that is, the bottom of the water supply tank 4 in which the water 70 is stored is located above the optical axis of the light emitting unit 30. The light emitted in the direction of the interface 72 is blocked. When the light emitting unit 30 has 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 emitting unit 35b is the lower side of each light emitting element 31, 32, 33. It is provided in each. The lower light-shielding portion 35b provided on 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 35b provided on 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 the occurrence of so-called crosstalk between the unpaired light emitting element and the light receiving element.

The upper shading portion 35a and the lower shading portion 35b have a plate shape extending in the vertical direction (vertical direction), a plate shape extending in the straight direction (horizontal direction) of the emitted light, or a vertical direction (vertical direction) and a straight direction (horizontal direction). ) Can be formed. The plate-shaped upper light-shielding portion 35a and lower light-shielding portion 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. Further, when the lower light-shielding portion 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 unit 35d that connects the upper light shielding unit 35a and the lower light shielding unit 35b as a light shielding unit. When the central light La of the emitted light is used for optical coupling, for example, as shown in FIG. 6, a closed loop shape including a connecting light-shielding portion 35d connecting both the left and right sides of the upper light-shielding portion 35a and the lower light-shielding portion 35b. Can be. According to the closed loop-shaped light-shielding portion, the light emitted in the vertical and horizontal directions is blocked. Examples of the closed loop shape include polygonal shapes 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 at the liquid surface 71 and the bottom interface 72 from being received, between the light receiving portion 40 and the light receiving side side wall portion 4c of the water supply tank 4, the same light receiving as the emitted light regulating portion 35a is received. A regulation unit 45a and another light reception regulation unit 45b similar to the other emission light regulation unit 35b are provided. The light receiving restricting unit 45a and the other light receiving restricting unit 45b are incorporated as a part of the light receiving unit 40, and the light receiving elements 41, 42 cover the light receiving side of the light receiving elements 41, 42, 43 except for the portion that receives light. , 43. The light receiving regulation portion 45a and the other light receiving regulating portion 45b may be arranged on the side of the light receiving side side wall portion 4c or on the intermediate portion between the light receiving portion 40 and the light receiving side side wall portion 4c.

On the light receiving side of the light receiving elements 41, 42, and 43, an upper light shielding portion 45a as a light receiving restricting portion, a lower light shielding portion 45b as another light receiving restricting portion, and a light receiving opening 45c that allows straight light to pass through are provided. Has been done.

The upper light-shielding portion 45a is provided above the light-receiving portion 40 to block light incident from above. That is, the light emitted above the optical axis of the light emitting unit 30 and reflected by the liquid level 71 of the water 70 stored in the water supply tank 4 above the optical axis of the light emitting unit 30. (Non-straight light) is blocked. When the light receiving unit 40 has 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), they are provided above the light receiving elements 41, 42, and 43, respectively. The upper light-shielding portion 45a provided on the second light-receiving element 42 has a function of blocking light emitted from the first light-emitting element 31. The upper light-shielding portion 45a provided on the third light-receiving element 43 has a function of blocking light emitted from the first light-emitting element 31 and the second light-emitting element 32. The light-shielding portion 45a can prevent the occurrence of so-called crosstalk between the unpaired light emitting element and the light receiving element.

The lower light-shielding portion 45b is provided below the light-receiving portion 40 to block light incident from below. That is, the bottom surface 4d of the water supply tank 4 in which the water 70 is stored and the liquid level 71 of the water 70 is emitted below the optical axis of the light emitting unit 30 and is above the optical axis of the light emitting unit 30, that is, the bottom interface. The light reflected by 72 (non-straight light) is blocked. When the light receiving unit 40 has 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 receiving unit 45b is the lower side of each light receiving element 41, 42, 43. It is provided in each. The lower light-shielding portion 45b provided on the first light-receiving element 41 has a function of blocking light emitted from the second light-emitting element 32 and the third light-emitting element 33. The lower light-shielding portion 45b provided on the second light-receiving element 42 has a function of blocking light emitted from the third light-emitting element 33. The lower light-shielding portion 45b can prevent the occurrence of so-called crosstalk between the unpaired light emitting element and the light receiving element.

The upper shading portion 45a and the lower shading portion 45b have a plate shape extending in the vertical direction (vertical direction), a plate shape extending in the straight direction (horizontal direction) of the incident light, or a vertical direction (vertical direction) and a straight direction (horizontal direction). ) Can be formed. The plate-shaped upper light-shielding portion 45a and lower light-shielding portion 45b can have, for example, a flat plate shape, a curved shape, or a triangular (gable) roof shape. When the upper light-shielding portion 45a has a curved shape or a triangular (gable) roof shape, it has a shape protruding upward. Further, when the lower light-shielding portion 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 shielding unit that connects the upper light shielding unit 45a and the lower light shielding unit 45b as a light shielding unit. When the central light La of the emitted light is used for optical coupling, it can have a closed loop shape including a connecting light-shielding portion connecting the left and right sides of the upper light-shielding portion 45a and the lower light-shielding portion 45b. According to the closed loop-shaped light-shielding portion, the light received in the vertical and horizontal directions is blocked. Examples of the closed loop shape include polygonal shapes such as a circular shape, a track shape, a triangular shape, a square shape, a rectangular shape, and a trapezoidal shape.

A method of detecting the storage level of the water 70 stored in the water supply tank 4 by using the transmission type optical coupling device 50 will be described with reference to FIGS. 4, 5, 10, 11 and 12.

FIG. 4 is a cross-sectional view schematically showing a transmission type optical coupling device 50 and a water supply tank 4 in which the device 50 is installed. FIG. 5 is a vertical cross-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 into the corner portion 4f on the rear side of the water supply tank 4 mounted on the main body casing 1a. The light receiving unit 40 is arranged to face the light emitting unit 30 so that the light emitted from the light emitting unit 30 toward the light emitting side side wall portion 4b crosses the corner portion 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 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 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 that the light is received by the unit 40.

In the transmissive optical coupling device 50 shown in FIG. 4, the light emitted from the light emitting portion 30 is emitted from the light emitting side side wall portion with respect to the water supply tank 4 in which the light emitting side side wall portion 4b and the light receiving side side wall portion 4c are at right angles. The light emitting portion 30 is positioned obliquely so as to form an angle with respect to 4b. Then, the light receiving portion 40 is obliquely positioned so that the light received by the light receiving portion 40 forms a marginal angle at a certain angle with respect to the light receiving side side wall portion 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 side wall portion 4c, and the light received by the light receiving unit 40 forms an angle of 45 degrees with respect to the light receiving side side wall portion 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. Further, 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, the first light receiving element 41, the second light emitting element 32, 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. Are arranged.

Of the light emitted from the first light emitting element 31, the light emitted in the direction of the liquid surface 71 is blocked by the upper light-shielding portion 35a to prevent the reflected light from being generated at the liquid surface 71. As a result, the reflected light on the liquid surface 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 35b to prevent the reflected light from being generated at the bottom interface 72. As a result, the reflected light at the bottom interface 72 is prevented from being received by the first light receiving element 41. Further, the light emitted from the light emitting elements (second light emitting element 32 and the 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, of the light emitted from the first light emitting element 31, the central light La, which is the light around the optical axis and has a relatively large emission 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, which is the light around the optical axis and has a relatively large emission luminous intensity, is optically coupled to the second light receiving element 42 to receive the second light. The light is directly received by the element 42. Of the light emitted from the third light emitting element 33, the central light La, which is the light around the optical axis and has a relatively large emission luminous intensity, is optically coupled to the third light receiving element 43, and the third light receiving element 43 It receives light directly.

Therefore, 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 arranged to face the light emitting unit 30 so that the light emitted from the light emitting unit 30 toward the light emitting side side wall portion 4b crosses the corner portion 4f on the rear side of the water supply tank 4. Has been done. As a result, the optical path length from the light emitting unit 30 to the light receiving unit 40 is shortened as compared with the case where the light emitting unit 30 and the light receiving unit 40 are installed on the opposite side wall portions of the water supply tank 4, due to the deviation of the optical axis. It is possible to prevent a decrease in optical coupling.

FIG. 11 is a circuit diagram when the photocurrents generated by the 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 of 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 by each of the light emitting elements 31, 32, 33, the light receiving elements 41, 42, 43 of the light receiving unit 40 receive photocurrent values I ₁ , I, depending on the amount of received light received. ₂ and I ₃ are output respectively. The light receiving unit 40 outputs an added value obtained by adding the respective 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 in 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, the 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 stored by being compared with the value corresponding to each storage level. The level is detected.

FIG. 10 shows the relationship between the storage level of water 70 in the water supply tank 4 and the output value (for example, output voltage) in the light receiving unit 40, and the mounting or detachment 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) of the light receiving unit 40 is schematically shown. In FIG. 10, the horizontal axis shows the storage level of the water 70 in the water supply tank 4, and the vertical axis shows the output value (for example, the output voltage) in the light receiving unit 40. The numerical values shown on the horizontal axis and the vertical axis are examples for facilitating understanding, and are not limited to the numerical values.

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

The initial full state is defined as a state in which the water supply tank 4 mounted at a predetermined position of the main body casing 1a is roughly filled with water 70. 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 the water supply to the steam generator 12, that is, the drainage from the water supply tank 4 will be described.

In the initial full state, the storage level (liquid level 71) of the water 70 is above the optical axes 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 is added according to the amount of light received by each light receiving element 41, 42, 43, but since each light receiving element 41, 42, 43 receives the light transmitted through the water supply tank 4 and the water 70. , The added value obtained by adding each output value 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 the high water storage stage where a little drainage is discharged from the full state, the storage level (liquid level 71) of the water 70 continues to be located above the optical axes of the first light emitting element 31 and the first light receiving element 41. , 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 near 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 increases and the output from the first light receiving element 41 The value tends to increase.

However, the output value is affected by the exit opening 35c of the first light emitting element 31 and the light receiving opening 45c of the first light receiving element 41. That is, since the first light emitting element 31 also 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 first light emitting element 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 paired first light emitting element 31 and the first light receiving element 41, the ratio of the exit aperture 35c and the light receiving opening 45c shaded by the water 70, that is, the aperture shading ratio (the exit opening 35c and the first light receiving element 41 of the first light emitting element 31). The total light-shielding area of the light-receiving 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 the water 70, with respect to the total opening area of the light-receiving openings 45c. The area) changes according to the storage level (liquid level 71) of the water 70. Therefore, when the storage level (liquid level 71) of the water 70 decreases in the first water storage stage, the aperture shading ratio in the first light emitting element 31 and the first light receiving element 41 decreases, so that the output from the first light receiving element 41 The value changes while gradually increasing as the output value B. That is, the output value B increases as it rises to the left. The above description is based on the premise that the light amounts of the emitted light and the incident light are uniform and uniform in the light emitting openings 35c of the first light emitting element 31 and the light receiving openings 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 32. It is in the middle water storage stage where the state of being located above the optical axis of 42 continues. Therefore, in the medium 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 becomes the second water storage stage located near the optical axis of the second light emitting element 32 and the second light receiving element 42. 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 increases and the output from the second light receiving element 42 increases. The value tends to increase. Similar to the first light emitting element 31 and the first light receiving element 41, the output value is affected by 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. 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 second light emitting element 42 also has a certain opening width. 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 second light emitting elements 32 and the second light receiving element 42, the ratio of the exit aperture 35c and the light receiving opening 45c shaded by the water 70, that is, the aperture shading ratio (the exit opening 35c and the second light receiving of the pair of second light emitting elements 32). The light-shielding areas of the second light-emitting element 32 and the light-receiving opening 45c of the second light-receiving element 42, which are shielded by the water 70, are totaled with respect to the total opening area of the light-receiving aperture 45c of the element 42. The total light-shielding area) changes according to the storage level (liquid level 71) of the water 70. Therefore, when the storage level (liquid level 71) of the water 70 decreases in the second water storage stage, the aperture shading 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 as it rises to the left. The above description is based on the premise that the light amounts of the emitted light and the incident light are uniform and uniform in the light emitting openings 35c of the second light emitting element 32 and the light receiving openings 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 axes 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 33 are located. It becomes a low water storage stage in which the state of being located above the optical axis of 43 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, the light emitted from the third light emitting element 33 is not affected by the water 70 in the water supply tank 4, so that the amount of light received by the third light receiving element 43 increases and the light emitted from the third light receiving element 42 The output value tends to increase. Similar to the first light emitting element 31 and the first light receiving element 41, the output value is affected by the exit opening 35c of the third light emitting element 33 and the light receiving opening 45c of the third light receiving element 43. That is, since 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 third light emitting element 43 also has a certain opening width. 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 elements 33 and the third light receiving element 43, the ratio of the exit aperture 35c and the light receiving opening 45c shaded by the water 70, that is, the aperture light blocking ratio (the exit opening 35c and the third light receiving of the pair of third light emitting elements 33). The light-shielding areas of the third light-emitting element 33 and the light-receiving opening 45c of the third light-receiving element 43 are totaled with respect to the total opening area of the light-receiving aperture 45c of the element 43. The total light-shielding area) changes according to the storage level (liquid level 71) of the water 70. Therefore, when the storage level (liquid level 71) of the water 70 decreases in the third water storage stage, the aperture shading ratio in the third light emitting element 33 and the third light receiving element 43 decreases, so that the output from the third light receiving element 43 The value changes while gradually increasing as the output value F. That is, the output value F increases as it rises to the left. The above description is based on the premise that the light amounts of the emitted light and the incident light are uniform and uniform in the light emitting openings 35c of the third light emitting element 33 and the light receiving openings 45c of the third light receiving element 43. I have to.

When further drainage is performed, the storage level (liquid level 71) of the water 70 continues to be located below the optical axis of the third light emitting element 33 and the third light receiving element 43, which is the bottom water storage stage. Therefore, at the bottom water storage stage, the output value has a certain output value G.

As described above, the output value of the light receiving unit 40 changes according to the storage level (liquid level 71) of the water 70 in the water supply tank 4. Therefore, the water supply tank is based on the output value of the light receiving unit 40. The storage level (liquid level 71) of the water 70 in 4 can be detected. That is, in this embodiment, the storage level (liquid level 71) of the water 70 in the water supply tank 4 is the high water storage stage (full state), the first water storage stage, the medium water storage stage, and the second water storage stage in this order from the top. , Low water storage stage, 3rd water storage stage and 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 main body casing 1a, and the water supply tank 4 The presence or absence of is detected 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 becomes maximum, and the water supply tank 4 is removed. The output value in the separated state is output as an output value H larger than the output value G.

Therefore, if an output value H in which the output value from the light receiving unit 40 is larger than the output value G is obtained, it is detected that the water supply tank 4 is detached from the predetermined position of the main body casing 1a. In the container detection unit 60a, the water supply tank 4 is mounted or detached from the main body 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. Determine if it is done. That is, the 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, the medium water storage stage, and the low water storage stage. As shown in FIG. 5, this corresponds to the arrangement of the light emitting elements 31, 32, 33 and the light receiving elements 41, 42, 43 in the water supply tank 4 in the height direction. 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 are spaced apart from each other. It is longer than between each other's optical paths and between the second light emitting element 32 and the second light receiving element 42 and between the third light emitting element 33 and the third light receiving element 43 (opening). It corresponds to. The distance between the optical paths (opening) between the three pairs of light emitting elements and the light receiving elements, and the distance between the optical paths (openings) of the third light emitting element 33 and the third light receiving element 43 and the bottom surface portion 4d When they are approximately equal, the lengths in the horizontal axis direction at the high water storage stage, the medium water storage stage, the low water storage stage, and the bottom water storage stage are approximately equal.

Further, as shown in FIG. 5, each emission opening 35c of each light emitting element 31, 32, 33 has the same opening width in the height direction, and each light receiving opening 45c of each light receiving element 41, 42, 43 has a height direction. Have the same opening width. Therefore, the lengths in the horizontal axis direction in the first water storage stage, the second water storage stage, and the third water storage stage are substantially equal. By increasing the opening widths of the exit opening 35c and the light receiving opening 45c in the height direction, the amount of emitted light and incident light can be increased. Taking advantage of this, the output value can be changed by increasing the width of each of the emission opening 35c and the light receiving opening 45c of the light emitting element and the light receiving element arranged at the place where the output value is desired to be greatly changed in the height direction. Can be increased.

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

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

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

When the water 70 is drained from the water supply tank 4, the liquid level 71 fluctuates slightly due to the influence of the drainage. Similarly, when the water 70 is injected into the water supply tank 4, the liquid level 71 slightly fluctuates due to the influence of the water injection. Therefore, if 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 and the threshold value e in the discharge direction of the water 70 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, the water 70 is injected) and exceeds the threshold d in the supply direction, the liquid level 71 of the water 70 Detects 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 top to bottom (that is, the water 70 is drained) and falls below the threshold value e in the discharge direction, the liquid level 71 of the water 70 Detects 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 stable even if the liquid level 71 fluctuates slightly, and the storage level of the water 70 in the water supply tank 4 is maintained. 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 according to the amount of light received in order to stabilize the level detection by the level detecting unit 60b. , The analog output may be filtered or averaged.

As described above, according to the present embodiment, the emitted light regulating unit 35a allows straight light to pass through, whereas non-straight light is blocked, so that the interface in the water supply tank 4 storing the water 70 ( The reflected light reflected by the liquid surface) 71 is reduced, and the reflected light is less likely to be received by the light receiving unit 40. Therefore, erroneous detection due to 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 transmission type optical coupling device 50 according to the second embodiment will be described with reference to FIGS. 7, 8 and 9. In the second embodiment, the components having the same functions as the components in the first embodiment are designated by the same reference numerals, and duplicate description will be 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 vertical cross-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, when viewed from the light emitting portion 30 side. FIG. 9 is a schematic vertical cross-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, including the light emitting portion 30 and the light receiving portion 40.

As shown in FIG. 9, each of the light emitting elements 31, 32, 33 of the light emitting unit 30 does not include the above-mentioned emission light regulation unit 35a and other emission light regulation unit 35b, and the light emitting unit 30 has a certain size. Light is emitted at the emission directional angle P of. The light receiving elements 41, 42, and 43 of the light receiving unit 40 also do not have the above-mentioned light receiving restricting unit 45a and other light receiving restricting unit 45b, and the light receiving unit 40 receives light at a light receiving directing angle Q of a certain size. To do. Further, the light emitting portion 30 is arranged on the light emitting side side wall portion 4b via the light emitting portion spacer 53, and the light receiving portion 40 is arranged on the light receiving side side wall 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 side wall portion 4b. The light emitting unit 30 is arranged diagonally. Then, the central light La of the light emitted from the light emitting unit 30 is optically coupled to the light receiving unit 40. According to this configuration, in the light emitting portion 30, the end portion on the side opposite to the light emitting side side wall portion 4b protrudes, the size of the transmissive optical coupling device 50 becomes large, and the mounting space becomes large.

The light emitted from the light emitting unit 30 generally has a light emitting directivity angle P of a certain size. Therefore, in the transmission type optical coupling device 50 according to the second embodiment, among the light emitted from the light emitting unit 30, the light emitting elements 31, 32, 33 having a light emitting directivity angle P of a certain size are used. The light emitting edge light Lp having a light emitting 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 a light emitting directivity angle P and the light receiving edge portion Lq having a light receiving directivity angle Q of the light received by the light receiving unit 40 are configured to be optically coupled. Has been done. 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 side wall portion 4b, and the light is received by the light receiving unit 40. The light receiving portion 40 is arranged so that the optical axis light is perpendicular to the light receiving side side wall portion 4c. In the light emitting portion 30, the protrusion of the end portion opposite to the light emitting side side wall portion 4b is suppressed, and in the light receiving portion 40, the protrusion of the end portion opposite to the light receiving side side wall portion 4c is suppressed, so that the transmitted light is transmitted. The size of the coupling device 50 is reduced, and the mounting space is reduced.

Therefore, the transmission type optical coupling device 50 does not have the emission light regulation unit 35a, another emission light regulation unit 35b, the light reception regulation unit 45a, and the other light reception regulation unit 45b, so that the light emitting unit 30 and the light receiving unit 40 are configured. It can be simplified. Since the protrusions of the light emitting unit 30 and the light receiving unit 40 are reduced, the installation space when the transmissive light coupling device 50 is installed in the cooking cooker 1 is reduced, and the dead space associated with the installation is reduced.

The arrangement of the light emitting portion 30 with respect to the light emitting side side wall portion 4b is not limited to the arrangement forming a right angle, and may be an arrangement inclined in the direction facing the light receiving portion 40. Further, the arrangement of the light receiving portion 40 with respect to the light receiving side side wall portion 4c is not limited to the arrangement forming a right angle, and may be an arrangement inclined in the direction facing the light emitting portion 30.

Although the specific embodiment of the present invention has been described, the present invention is not limited to the above embodiment, and can be implemented by 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 detecting the storage level, but light other than near-infrared light (for example, visible light) may be used.

Further, in the above embodiment, the output value from the light receiving unit 40 is a voltage, but the output value is not limited to this, and may be, for example, a current.

Further, in the above embodiment, the water supply tank 4 as a container is composed of a transparent member, but it may be composed of a translucent member as long as it has light transmission. Similarly, water 70 as a liquid is transparent, but may be a translucent liquid as long as it has light transmittance. In particular, as in water and air, the greater the difference in refractive index between the liquid 70 and the gas 74, the more effective it is.

Further, in the above embodiment, the storage level of the water 70 is detected, but the storage level (liquid level) of the liquid 70 such as a known cleaning liquid containing a citric acid solution may be detected. Further, it goes without saying that the storage level (liquid level) can be detected even in a liquid 70 having a very small or small light transmittance, for example, ink.

Further, in the above 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, but separately provided hardware (for example, a mechanical (mechanical) switch). ) May detect the attachment or detachment of the water supply tank 4.

Further, in the above embodiment, the level detection unit 60b detects the storage level based on the added value obtained by adding a plurality of output values (photocurrent values), but is individually for each pair of light emitting element and light receiving element. The storage level may be detected by comparing the individual output values with the values corresponding to the storage levels with a comparator.

The light emitted from the light emitting unit 30 is emitted substantially horizontally so that the light emitting unit 30 and the light receiving unit 40 are located at substantially the same level, but the present invention is not limited to this. For example, the light emitted from the light emitting unit 30 may be emitted obliquely upward or diagonally downward with respect to the horizontal plane so that the light emitting unit 30 and the light receiving unit 40 are located 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 the light receiving elements at the positions where the storage level (liquid level) of the liquid 70 is desired to be detected.

Further, in the above 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, 33 and light receiving elements 41, 42, 43 are used, but one pair. A light emitting element and a light receiving element, two pairs of light emitting elements and a light receiving element, and four or more pairs of light emitting elements and a light receiving element may be used.

[Third Embodiment]
Further, in the electric device 1 in which electromagnetic noise is generated such as a microwave oven, in order to reduce the noise entering the light emitting element and the light receiving element, the emitted light regulating unit 35a, another emitting light regulating unit 35b, and the light receiving regulating unit 45a are used. And the other light receiving regulation unit 45b may be made of a conductive material and grounded.

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

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

As shown in FIG. 13, an inclined portion 4e whose outer portion is obliquely cut out is formed on the bottom surface portion 4d of the corner portion 4f of the water supply tank 4. A pair of a third light emitting element 33 and a third light receiving element 43 are arranged at positions 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 a pair of the first light emitting element 31 and the first light receiving element 41 are arranged in this order from the bottom. Although it is provided, in FIG. 13, the pair of the first light emitting element 31 and the first light receiving element 41 are not shown.

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 the other portions (high water storage stage, medium water storage stage, etc.). The shorter the optical path length inside the water supply tank 4 in which the water 70 is stored, the less the light is attenuated by the water 70, and the larger the amount of light received by the third light receiving element 43. In addition, since the notch due to the inclined portion 4e exists on the bottom surface portion 4d, the internal volume on the bottom surface portion 4d side becomes smaller than the internal volume of other portions (high water storage stage, medium water storage stage, etc.). ing. Due to these factors, if the volume of the water 70 stored on the bottom surface 4d side of the water supply tank 4 changes slightly, the amount of light received by the third light receiving element 43 changes significantly, and the change in the output value also becomes large. As a result, as shown in FIG. 14, the inclination of the output value F becomes larger than the inclination of the output value D due to the inclined portion 4e formed on the bottom surface portion 4d side, and the output value F is likely to change. Therefore, by utilizing the fact that the output value F on the bottom surface 4d side is easily changed, when the water 70 is discharged from the water supply tank 4, the change in the storage level on the bottom surface 4d side can be detected in more detail, and the water supply can be performed. The amount of residual water in the tank 4 before the water 70 runs out can be detected in more detail.

In the first to fourth embodiments, the heating cooker 1 (specifically, the steam cooker) has been described as an electric device. For example, it has a jar rice cooker having a water supply tank for moisturizing and a tank for liquid detergent. Washing machines, vacuum cleaners with water filter tanks, refrigerators with ice-making water tanks, air purifiers and ion generators with humidification water tanks, coffee makers with water tanks, irons with steam generation tanks, etc. , Applicable 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 machines having a container 4 for collecting the discharged liquid 70, such as an air purifier having a dehumidifying recovery tank, an ion generator, and a tableware dryer having a water droplet recovery tank, etc. It can also be applied to device 1.

As described above, the transmissive optical coupling device 50 of the present invention
A transmissive optical coupling device 50 capable of detecting the storage level of the light-transmitting liquid 70 stored in the light-transmitting container 4.
A light emitting portion 30 that emits light toward the side wall portion 4b of the container 4 and
A light receiving unit 40 that receives light emitted from the light emitting unit 30 and transmitted through the container 4 and
A level detection unit 60b that detects 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.
Of the light emitted from the light emitting unit 30, the light that travels straight in the direction of the light receiving unit 40 and is emitted can pass through, while the gas that passes through the liquid 70 and is in contact with the liquid 70 and the liquid 70. It is characterized by including an emitted light regulating unit 35a that blocks non-straight light that can be reflected light reflected at the interface 71 with 74.

According to the above configuration, the emitted light restricting unit 35a allows straight light to pass through, whereas non-straight light is blocked, so that the light passes through the liquid 70 (the liquid surface 71 is above the optical axis for receiving and emitting light). Then, the reflected light reflected at the interface 71 between the liquid 70 and the gas 74 is reduced, and the reflected light is less likely to be received by the light receiving unit 40. Therefore, erroneous detection due to reflected light can be prevented, and the storage level of the liquid 70 stored in the container 4 can be accurately detected.

Preferably, in the transmission type light coupling device 50, the emission light regulation unit is an upper light shielding unit 35a provided above the light emitting unit 30.

According to the above configuration, since 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 blocked by the upper light shielding unit 35a, the liquid surface reflected at the interface 71 between the liquid 70 and the gas 74 is blocked. 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 light coupling device 50 has a lower light-shielding unit 35b provided under the light-emitting unit 30 as another emission light regulating unit.

According to the above configuration, the lower light-shielding portion 35b shields the non-straight light emitted in the bottom surface portion 4d direction of the container 4, so that the bottom surface reflected light reflected by the bottom surface portion 4d of the container 4 in which the liquid 70 is stored is emitted. Since the amount is reduced and the bottom reflected light is less likely to be received by the light receiving unit 40, erroneous detection due to the bottom 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 or detached from a predetermined location.
The container detection unit 60a detects the detachment of the container 4 when the light receiving amount of the light receiving unit 40 is larger than the light receiving amount when detecting the storage level of the liquid 70.

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 transmission type 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 fluctuates due to drainage or water injection, the level detection by the level detection unit 60b can be stabilized.

Preferably, in the transmission type optical coupling device 50, the light receiving unit 40 performs an analog output according to the amount of light received, 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 fluctuates due to drainage or water injection, the level detection by the level detection unit 60b can be stabilized.

Further, the electric device 1 of the present invention includes the above-mentioned transmissive optical coupling device 50.

According to the above configuration, by arranging the light emitting unit 30 and the light receiving unit 40 at the desired height, it is possible to adjust so that the output changes 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 reliably and stably detected.

Preferably, in the electric device 1, the light emitting unit 30 and the light receiving unit 40 are arranged on adjacent side wall portions 4b and 4c in the container 4, and the light emitted from the light emitting unit 30 is the electricity. The transmissive optical coupling device 50 is configured so as to cross the corner portion 4f of the container 4 mounted on the device 1.
The light emitting unit 30 and the light receiving unit 40 are arranged to face each other and optically coupled.

According to the above configuration, the optical path length from the light emitting unit 30 to the light receiving unit 40 is shorter than in the case where the light emitting unit 30 and the light receiving unit 40 are installed on the opposite side wall portions of the container 4, and the optical axis It is possible to prevent a decrease in optical coupling due to displacement. Further, according to the above configuration, the optical characteristics such as refraction and total reflection of light differ depending on the presence or absence of the liquid 70 in the container 4, and the output from the light receiving unit 40 differs. 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
An electric device 1 provided with a transmissive optical coupling device 50 capable of detecting the storage level of a light transmissive liquid 70 stored in a light transmissive container 4.
A light emitting portion 30 that emits light toward the side wall portion 4b of the container 4 and
A light receiving unit 40 that receives light emitted from the light emitting unit 30 and transmitted through the container 4 and
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 is provided.
The light emitting unit 30 and the light receiving unit 40 are arranged on adjacent side wall portions 4b and 4c of the container 4, respectively, and the light emitted from the light emitting unit 30 is mounted on the electric device 1. The transmissive optical coupling device 50 is configured so as to cross the corner portion 4f of the above.
Of the light emitted from the light emitting unit 30, the light emitting edge light Lp having a light emitting directivity angle P and the light receiving edge portion Lq having a 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 transmission type optical coupling device 50 does not have the emission light regulation unit 35a, another emission light regulation unit 35b, the light reception regulation unit 45a, and the other light reception regulation unit 45b, the light emitting unit 30 and the light receiving unit 45b. The configuration of 40 can be simplified. Since the protrusions of the light emitting unit 30 and the light receiving unit 40 are reduced, the installation space when the transmissive optical coupling device 50 is installed in the electric device 1 is reduced, and the dead space associated with the installation is reduced.

Preferably, in the electric device 1, the light emitting unit 30 and the light receiving unit 40 are 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. Have each
All of the plurality of light emitting elements 31, 32, 33 in the light emitting unit 30 are made to emit light, and the light receiving unit 40 adds the respective photocurrent values generated by the plurality of light receiving elements 41, 42, 43. Outputs the output value corresponding to the added value.

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 independently driven and output.

Preferably, in the electric device 1, the container detection unit 60a for detecting that the container 4 is attached or detached in a predetermined place, and the container detection unit 60a.
A storage unit 22 that stores the amount of light received by the light receiving unit 40 as the initial amount of light received when the container detection unit 60a detects the detachment of the container 4 at the initial stage of operation.
The initial light reception amount is compared with the light reception amount received by the light receiving unit 40 when the container detection unit 60a detects the detachment of the container 4, and the initial light reception amount stored in the storage unit 22. A light receiving amount reduction detecting unit 60c for detecting whether or not the decrease in the received light amount with respect to the amount is larger than a predetermined value, and
A notification unit 23 for notifying the decrease in the received light amount when the decrease in the received light amount with respect to the initial received light amount is larger than a predetermined value is provided.

According to the above configuration, when the decrease in the light receiving amount becomes larger than the predetermined value as compared with the initial operation, the notification is given. Therefore, the light emitting unit 30 and the light receiving unit 40 are deteriorated or the light emitting unit 30 and the light receiving unit 40 are provided. It is possible to detect dirt on the lens.

1 Cooker (electrical equipment)
1a Main body casing 2 Heating chamber 4 Water supply tank (container)
4a Lid 4b Light emitting side side wall part 4c Light receiving side side wall part 4d Bottom part 4f Corner part 4e Inclined part 22 Storage part 23 Notification part 30 Light emitting part 31 First light emitting element 32 Second light emitting element 33 Third light emitting element 34 Light emitting board 35a Light-shielding part (emission light regulation part)
35b Lower shading part (other emission light regulation part)
35c Emission opening 35d Connected 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 board 45a Upper light-shielding part (light-receiving part)
45b Lower light-shielding part (other light-receiving part)
45c Light receiving opening 50 Transmission type optical coupling device 52 Support 53 Light emitting part spacer 54 Light receiving part spacer 60 Control device 60a Container detection part 60b Level detection part 60c Light receiving amount decrease detection part 70 Water (liquid)
71 Liquid level (interface)
72 Bottom interface (interface)
74 Air (gas)
P Emission directivity angle Q Receiving directivity angle La Central light Lp Emission edge light Lq Receiving edge

Claims (10)

A transmissive optical coupling device capable of detecting the storage level of a light-transmitting liquid stored in a light-transmitting container.
A light emitting portion that emits light toward the side wall portion of the container, and a light emitting portion.
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container, and a light receiving unit.
A level detection unit that detects the storage level of the liquid stored in the container based on the amount of light received by the light receiving unit.
Of the light emitted from the light emitting unit, the straight light emitted in the direction of the light receiving unit can pass through, while being transmitted through the liquid and reflected at the interface between the liquid and the gas in contact with the liquid. and a light emitted regulating portion for shielding the non-straight light that can be the reflected light,
Further provided with a container detection unit for detecting that the container is attached or detached from a predetermined place.
The container detector, the light receiving amount of the light receiving portion is larger than the received light amount in the case of detecting the storage level of the liquid, transmission type optical coupling characterized that you detect the detachment of the container apparatus. The transmissive light coupling device according to claim 1, wherein the emitted light regulating unit is an upper light-shielding unit provided above the light emitting unit. The transmissive light coupling device according to claim 1 or 2, further comprising a lower light-shielding portion provided below the light-emitting portion as another emitted light regulating portion. The transmissive optical coupling device according to any one of claims 1 to 3 , wherein the level detection unit has hysteresis. The method according to any one of claims 1 to 3 , wherein the light receiving unit performs an analog output according to the amount of light received, and performs a filtering process or an averaging process on the analog output. Transmission type optical coupling device. An electric device including the transmissive optical coupling device according to any one of claims 1 to 5 . The light emitting portion and the light receiving portion are respectively arranged on adjacent side wall portions of the container, and the light emitted from the light emitting portion is transmitted so as to cross the corner portion of the container mounted on the electric device. A type optical coupling device is configured
The electric device according to claim 6 , wherein the light emitting portion and the light receiving portion are arranged so as to face each other and optically coupled. An electrical device provided with a transmissive optical coupling device capable of detecting the storage level of a light-transmitting liquid stored in a light-transmitting container.
A light emitting portion that emits light toward the side wall portion of the container, and a light emitting portion.
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container, and a light receiving unit.
A level detection unit that detects the storage level of the liquid stored in the container based on the amount of light received by the light receiving unit.
A container detection unit that detects that the container is attached or detached in a predetermined place,
A storage unit that stores the amount of light received by the light receiving unit as the initial amount of light received when the container detection unit detects the detachment of the container at the initial stage of operation.
The amount of light received by the light receiving unit when the container detection unit detects the detachment of the container is compared with the amount of initial light received stored in the storage unit, and the light received with respect to the initial amount of light received is compared. A light receiving amount decrease detection unit that detects whether or not the amount decrease is larger than a predetermined value,
A notification unit for notifying the decrease in the received light amount when the decrease in the received light amount with respect to the initial received light amount is larger than a predetermined value is provided.
The light emitting portion and the light receiving portion are respectively arranged on adjacent side wall portions of the container, and the light emitted from the light emitting portion is transmitted so as to cross the corner portion of the container mounted on the electric device. A type optical coupling device is configured
An electric device characterized in that the light emitting edge portion of the light emitting directivity angle of the light emitted from the light emitting portion and the light receiving edge portion of the light receiving directivity angle of the light received by the light receiving portion are optically coupled. .. The light emitting unit and the light receiving unit each have 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 are made to emit light, and the light receiving unit outputs an output value corresponding to an added value obtained by adding the respective photocurrent values generated by the plurality of light receiving elements. The electrical device according to claim 6 or 8, which is characterized. An electrical device provided with a transmissive optical coupling device capable of detecting the storage level of a light-transmitting liquid stored in a light-transmitting container.
A light emitting portion that emits light toward the side wall portion of the container, and a light emitting portion.
A light receiving unit that receives light emitted from the light emitting unit and transmitted through the container, and a light receiving unit.
A level detection unit that detects the storage level of the liquid stored in the container based on the amount of light received by the light receiving unit.
Of the light emitted from the light emitting unit, the straight light emitted in the direction of the light receiving unit can pass through, while being transmitted through the liquid and reflected at the interface between the liquid and the gas in contact with the liquid. Equipped with an emission light control unit that blocks non-straight light that can be reflected light
A container detection unit that detects that the container is attached or detached in a predetermined place,
A storage unit that stores the amount of light received by the light receiving unit as the initial amount of light received when the container detection unit detects the detachment of the container at the initial stage of operation.
The amount of light received by the light receiving unit when the container detection unit detects the detachment of the container is compared with the amount of initial light received stored in the storage unit, and the light received with respect to the initial amount of light received is compared. A light receiving amount decrease detection unit that detects whether or not the amount decrease is larger than a predetermined value,
Wherein when reduction in the received light amount with respect to the initial amount of light received is greater than a predetermined value, characterized by comprising a notification unit that notifies a decrease in the amount of received light, electrical equipment.

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