JP2020176766A - Infrared detection unit and heating cooker - Google Patents

Abstract

To provide an infrared detection unit that can determine whether to correctly perform simplification of an assembly work, consolidation of components, downsizing and detection with infrared ray.SOLUTION: An infrared detection unit comprises: a housing H having a translucent window 30 oriented at an opening part 1a; a light receiving sensor 80 for determination, which is fixed to the inside of the housing and determines a closed state of the opening part and a dirty state of the translucent window; an infrared light source 100 which is fixed to the outside of the housing, and emits infrared ray toward the translucent window; and an optical element 90 for determination, which is fixed to the inside of the housing, guides infrared ray IR3 radiated from a heating source 4 and passed through the opening part 1a and the translucent window 30 to the light receiving sensor 80 for determination, and guides infrared ray IR4 radiated from the infrared light source 100 and passed through the translucent window 30 to the light receiving sensor 80 for determination.SELECTED DRAWING: Figure 2

Description

The present invention relates to an infrared detection unit applied when measuring the temperature of an object to be heated by using infrared rays, and particularly measures the temperature of an object to be heated such as a pot and a frying pan in a heating cooking device such as a gas stove. At the same time, the present invention relates to an infrared detection unit capable of detecting a state such as dirt that blocks infrared rays for temperature measurement, and a cooking apparatus provided with the infrared detection unit.

As a conventional cooking device, a burner that heats the container placed on Gotoku on the top plate, a translucent window fixed so as to close the opening of the top plate, and placed directly under the translucent window in the housing. An infrared intensity detector that detects the infrared intensity emitted from the container through the translucent window, a stain determination light receiving means that is placed diagonally below the transmissive window in the housing and detects the infrared intensity emitted from the flame of the burner, etc. A gas stove is known (for example, Patent Document 1).

In this gas stove, since the opening of the top plate is closed by the translucent window, it is possible to prevent the boiled broth and solid matter from entering the housing, but since the translucent window is close to the flame, it is translucent. There is room for improvement in terms of heat resistance and durability of windows and their fixing agents.
On the other hand, if the translucent window is abolished and the opening of the top plate is opened, there is a risk that the boiled broth or solid matter may enter the housing and stain the surface of the infrared intensity detection unit. In this case, it is necessary to detect the dirty state of the surface of the infrared intensity detecting unit.
In addition, the opening may be blocked by a solid substance or the like, and the infrared optical path may be blocked. In this case, it is necessary to detect the closed state of the opening.
Further, in the gas stove, since the light receiving means for determining stains is provided separately from the infrared intensity detecting unit, each arrangement space is required, which complicates the assembly work, increases the work man-hours, and the housing. It causes the body to become larger.

Japanese Unexamined Patent Publication No. 2013-204918

The present invention has been made in view of the above circumstances, and an object of the present invention is to solve the conventional problems, to simplify the assembly work, to consolidate parts, to reduce the size, and the like. An object of the present invention is to provide an infrared detection unit and a cooking device capable of determining whether or not detection by infrared rays can be normally performed.

The infrared detection unit of the present invention is for determining a housing having a translucent window oriented to a predetermined opening, and a determination state fixed inside the housing to determine a closed state of the opening and a dirty state of the translucent window. For determining the light receiving sensor, the infrared light source fixed on the outside of the housing and emitting infrared rays toward the translucent window, and the infrared rays fixed on the inside of the housing and radiated from the heating source and passing through the opening and the translucent window. It includes a determination optical element that guides the infrared rays that are guided to the light receiving sensor and that are emitted from the infrared light source and pass through the translucent window to the judgment light receiving sensor.

In the infrared detection unit, the judgment optical elements include a first reflection mirror that guides infrared rays radiated from a heating source to a judgment light receiving sensor, and a second reflection that guides infrared rays radiated from an infrared light source to a judgment light receiving sensor. A configuration may be adopted that includes a mirror.

In the infrared detection unit, the first reflection mirror and the second reflection mirror may adopt a configuration in which they are integrally formed as a single member.

In the infrared detection unit, a light receiving sensor for temperature measurement for measuring the temperature of an object to be heated fixed inside the housing and heated by a heating source, and an opening fixed inside the housing and radiated from the object to be heated. And a configuration may be adopted that further includes a temperature measuring optical element that guides infrared rays passing through the translucent window to the temperature measuring light receiving sensor.

In the infrared detection unit, the optical axis between the light receiving sensor for judgment and the optical element for judgment is arranged at a twisted position with respect to the optical axis between the light receiving sensor for temperature measurement and the optical element for temperature measurement. Yes, the configuration may be adopted.

In the infrared detection unit, the housing has a partition wall that separates a first region in which the temperature measuring light receiving sensor and the temperature measuring optical element are arranged and a second region in which the judgment light receiving sensor and the determination optical element are arranged. Adopting a configuration that includes a through hole in the partition wall to guide the infrared rays radiated from the heating source and the infrared rays radiated from the infrared light source from the first region to the determination optical element in the second region. May be good.

In the infrared detection unit, the temperature measuring light receiving sensor receives the first light receiving element that receives the infrared rays in the first wavelength region radiated from the object to be heated and the infrared rays in the second wavelength region radiated from the object to be heated. A configuration may be adopted that includes a second light receiving element.

In the infrared detection unit, the temperature measuring optical element may adopt a configuration including a first optical element corresponding to the first light receiving element and a second optical element corresponding to the second light receiving element.

In the infrared detection unit, a light shielding plate arranged inside the housing in order to prevent mutual interference between the infrared rays from the first optical element toward the first light receiving element and the infrared rays from the second optical element toward the second light receiving element. A configuration may be adopted that further includes.

In the infrared detection unit, the housing is a first that holds a light receiving sensor for judgment, an optical element for judgment, a light receiving sensor for temperature measurement, a housing body that holds the optical element for temperature measurement, a translucent window, and an infrared light source. A configuration may be adopted that includes a housing cover.

In the infrared detection unit, the housing body defines a first region in which the temperature measurement light receiving sensor and the temperature measurement optical element are arranged and a second region in which the determination light receiving sensor and the determination optical element are arranged. , The first housing cover may adopt a configuration that is assembled to the housing body so as to cover the first region.

In the infrared detection unit, the housing may adopt a configuration including a second housing cover assembled to the housing body so as to cover the second region.

The infrared detection unit further includes a determination unit for determining the closed state of the opening and the dirty state of the translucent window based on the output signal of the light receiving sensor for determination, and the determination unit receives infrared rays radiated from the heating source. A configuration may be adopted in which the closed state of the opening is determined based on the output of the light receiving sensor for determination.

In the infrared detection unit, the determination unit may adopt a configuration in which the determination unit determines the dirty state of the translucent window based on the difference in the output signals output by the determination light receiving sensor by turning on / off the infrared light source. ..

The heating cooking apparatus of the present invention is arranged below a top plate having a predetermined opening, a heating source for heating an object to be heated placed above the top plate, and radiated from the object to be heated. A cooking apparatus including an infrared detection unit that detects infrared rays that pass through the opening or infrared rays that are radiated from a heating source and pass through the opening, and the infrared detection unit has any of the above configurations. The infrared detection unit that forms the above is adopted.

In the above-mentioned cooking apparatus, the translucent window of the infrared detection unit is arranged in a region deviating from the vertically downward region of the opening in a state in which the normal passing through the center of the transmissive window is inclined toward the opening. , The configuration may be adopted.

According to the infrared detection unit and the cooking device having the above configuration, it is possible to achieve simplification of assembling work, consolidation of parts, miniaturization, etc., and it is possible to determine whether or not infrared detection can be performed normally. it can.

It is an external perspective view which shows one Embodiment of the cooking apparatus to which the infrared ray detection unit which concerns on this invention is applied. It shows one embodiment of the infrared ray detection unit which concerns on this invention, and is the external perspective view which shows the arrangement relation with respect to the opening of the top plate of the cooking apparatus shown in FIG. FIG. 5 is a partial side view showing a state in which infrared rays radiated from an object to be heated on a top plate are guided to an infrared ray detection unit through an opening in the cooking apparatus shown in FIG. FIG. 3 is a partial plan view showing a state in which infrared rays radiated from an object to be heated on a top plate are guided to an infrared ray detection unit through an opening in the cooking apparatus shown in FIG. FIG. 5 is a partial side view showing a state in which infrared rays radiated from a heating source on a top plate are guided to an infrared ray detection unit through an opening in the cooking apparatus shown in FIG. FIG. 3 is a partial plan view showing a state in which infrared rays radiated from a heating source on a top plate are guided to an infrared ray detection unit through an opening in the cooking apparatus shown in FIG. FIG. 5 is an exploded perspective view of the infrared detection unit shown in FIG. 2 disassembled and viewed from above. FIG. 5 is an exploded perspective view of the infrared detection unit shown in FIG. 2 disassembled and viewed from below. It is a perspective cross-sectional view partially shown by cutting the housing of the infrared ray detection unit shown in FIG. 2 on the side surface passing through the temperature measuring light receiving sensor. It is a perspective cross-sectional view partially shown by cutting the housing of the infrared ray detection unit shown in FIG. 2 in the vertical plane passing through the light receiving sensor for judgment. It is an exploded perspective view which disassembled the housing body of the infrared ray detection unit shown in FIG. 2 and viewed from the lower oblique side. In the infrared detection unit shown in FIG. 2, infrared rays radiated from an object to be heated pass through an opening, a light-transmitting window, and an optical element for temperature measurement (first optical element, second optical element), and a light receiving sensor for temperature measurement. It is a perspective view which shows the state which is guided to (the 1st light receiving element, the 2nd light receiving element). In the infrared detection unit shown in FIG. 2, a perspective view showing a state in which infrared rays radiated from a heating source are guided to a light receiving sensor for judgment through an opening, a translucent window, and an optical element for judgment (first reflection mirror). Is. In the infrared detection unit shown in FIG. 2, it is a perspective view showing a state in which infrared rays emitted from an infrared light source are guided to a light receiving sensor for judgment through a transparent window and an optical element for judgment (second reflection mirror). .. It is a perspective view which shows the state which showed the infrared ray shown in FIG. 12, the infrared ray shown in FIG. 13, and the infrared ray shown in FIG. 14 together. It is a perspective view which looked at the state shown in FIG. 15 from another angle. It is a block diagram which shows the system of the circuit board included in the infrared ray detection unit which concerns on this invention.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
As shown in FIG. 1, the cooking apparatus according to one embodiment includes a top plate 1 that defines an opening 1a, a housing 2 that is closed by the top plate 1, and a pot or the like that is arranged on the upper surface of the top plate 1. It includes a trivet 3 on which the object W to be measured can be placed, a gas burner 4 as a heating source for burning gas, and an infrared detection unit U arranged in a housing 2 below the top plate 1.
Further, the cooking apparatus includes a supply pipe that mixes and supplies fuel gas and air to the gas burner 4, a gas nozzle provided on the upstream side of the supply pipe, an adjustment valve that adjusts the flow rate of the fuel gas supplied to the gas nozzle, and adjustment. It is provided with a combustion control circuit that controls a valve to adjust the combustion amount of the gas burner 4, and a display notification circuit that displays and notifies various information.

The top plate 1 is formed of a metal material such as stainless steel, and the opening 1a is formed by punching the top plate 1 into a circular shape and penetrating it.
The gas burner 4 is a Bunzen combustion type external flame burner, and flames 4a (see FIG. 5) are ejected from a plurality of flame ports arranged outward in a ring shape.

As shown in FIGS. 2, 7, and 8, the infrared detection unit U includes a housing body 10 and a housing cover 20 as a housing H, a translucent window 30, a first light receiving system 40, and a second light receiving system 50. Temperature light receiving sensor LS, temperature measurement optical element LE including first optical element 60 and second optical element 70, judgment light receiving sensor 80, judgment optical element 90, infrared light source 100, shading plate 110, circuit board 120 It has.
Then, as shown in FIGS. 3, 4, and 12, the infrared detection unit U measures the temperature of the object W to be heated based on the intensity of infrared rays radiated from the object W to be heated, and the infrared detection unit U measures the temperature of the object W to be heated. As shown in FIG. 13, the blocked state of the opening 1a is determined based on the infrared intensity emitted from the flame 4a of the gas burner 4, and as shown in FIG. 14, it is based on the infrared intensity emitted from the infrared light source 100. It functions to determine the dirty state of the translucent window 30.

Here, in a state where the infrared detection unit U is fixed in the housing 2 of the cooking apparatus, as shown in FIG. 2, the transmission window 30 is arranged in a region outside the vertically lower region of the opening 1a. The translucent window 30 is arranged in an inclined state oriented toward the opening 1a so that the normal line N passing through the center of the transmissive window 30 faces the opening 1a.
By arranging the translucent window 30 in this way, even if foreign matter such as boiled broth or solid matter enters the housing 2 through the opening 1a, the foreign matter falls directly onto the translucent window 30. Even if the broth or the like splashes and adheres to the translucent window 30, it can be prevented from dripping naturally along the inclined surface and solidifying and staying on the surface of the translucent window 30.

The housing body 10 is formed of an aluminum material or the like, and is composed of a first housing body 11 and a second housing body 12 as shown in FIGS. 7 to 11.
The inner wall of the first housing body 11 is painted black, and the multi-stage fitting hole 11a for fixing the first light receiving system 40, the multi-stage fitting hole 11b for fixing the second light receiving system 50, and the first optical element 60. Fitting hole 11c for fixing, fitting hole 11d for fixing the second optical element 70, boss portion 11e for fixing the circuit board 120, recess 11f for attaching the light-shielding plate 110, joint surface 11g, cover joint portion 11h, 11i, 11j, a fixing portion 11k fixed to the leg portion 2a of the housing 2 is provided.
The inner wall of the second housing body 12 is painted black, and the multi-stage fitting hole 12a for fixing the judgment light receiving sensor 80, the boss portion 12b for fixing the judgment optical element 90, the joint surface 12c, the partition wall 12d, and the partition It is provided with a through hole 12e formed in the wall 12d, a recess 12f for attaching a light-shielding plate 110, and a cover joint portion 12g.

Here, the housing body 10 is formed by joining the joint surface 12c to the joint surface 11g and assembling the second housing body 12 to the first housing body 11 with screws or the like.
The housing body 10 has a first region A1 in which the temperature measuring light receiving sensor LS and the temperature measuring optical element LE are arranged, and the determination light receiving sensor 80 and the determination optical element 90 are arranged with the partition wall 12d as a boundary. It defines the second region A2 to be formed.
Further, the through hole 12e is an optical for determining the infrared IR ₃ radiated from the flame 4a of the gas burner 4 as a heating source and the infrared IR ₄ radiated from the infrared light source 100 in the first region A1 to the second region A2. It is formed to lead to element 90.

As described above, since the housing body 10 has a two-divided structure of the first housing body 11 and the second housing body 12, machining is easy and various parts can be easily assembled. ..
Further, a partition wall 12d is provided, and a first region A1 in which the temperature measuring light receiving sensor LS and the temperature measuring optical element LE are arranged and a second region A2 in which the determination light receiving sensor 80 and the determination optical element 90 are arranged. By separating the above, the infrared IRs ₁ and IR ₂ incident on the first light receiving element 41 and the second light receiving element 51 and the infrared IRs ₃ and IR ₄ incident on the light receiving element 81 are surely prevented from interfering with each other. be able to.

As shown in FIGS. 7 and 8, the housing cover 20 is composed of a first housing cover 21, a second housing cover 22, a third housing cover 23, and a fourth housing cover 24.

The first housing cover 21 is formed of an aluminum material or the like, and its inner wall is infrared-absorbed, for example, painted black, and has a rectangular edge 21a for fixing the translucent window 30, and a fixing portion 21b for fixing the infrared ray 100. A joint surface 21c to be joined to the cover joint portion 11h of the first housing body 11 is provided.
Then, in the first housing cover 21, the joint surface 21c is joined to the cover joint portion 11h in a state where the translucent window 30 is fixed to the edge portion 21a by an adhesive or the like and the infrared light source 100 is fixed to the fixed portion 21b. Then, it is assembled to the first housing body 11 with screws or the like so as to cover the first region A1 to prevent light from entering the first region A1 from the outside except for the region of the translucent window 30.

The second housing cover 22 is formed of a resin material such as polyacetal, and its inner wall is subjected to infrared absorption processing, is painted black, for example, and has a joint surface 22a.
Then, in the second housing cover 22, the joint surface 22a is joined to the cover joint portion 12g in a state where the judgment light receiving sensor 80 and the judgment optical element 90 are assembled, and the second housing covers the second region A2. It is attached to the body 12 with screws or the like to prevent light from entering the second region A2 from the outside.

The third housing cover 23 is formed of an aluminum material or the like, and its inner wall is subjected to infrared absorption processing, is painted black, for example, and has a joint surface 23a.
Then, in the third housing cover 23, with the first optical element 60 and the second optical element 70 assembled, the joint surface 23a is joined to the cover joint portion 11i and attached to the first housing body 11 with screws or the like. , Prevents light from entering the housing H from the outside.

The fourth housing cover 24 is formed of a resin material such as polyacetal and has a joint surface 24a.
Then, in the fourth housing cover 24, with the first light receiving system 40, the second light receiving system 50, and the circuit board 120 assembled, the joint surface 24a is joined to the cover joint portion 11j and screwed to the first housing body 11. It is assembled by such means as covering and protecting the internal parts.

The translucent window 30 is formed in a substantially rectangular flat plate shape as shown in FIGS. 2 and 7 by using an infrared transmissive material such as silicon that transmits infrared light.
Here, as the infrared transmitting material, the infrared rays in the first wavelength region λ1 and the second wavelength region λ2 radiated from the object W to be heated, the flame 4a of the gas burner 4 and the third wavelength region λ3 radiated from the infrared light source 100 A material that transmits at least the infrared rays of the above is appropriately selected.
The outer edge region of the transmission window 30 is fitted into the edge portion 21a and fixed to the first housing cover 21 with an adhesive or the like.

The first light receiving system 40 constitutes a part of the temperature measuring light receiving sensor LS, and as shown in FIG. 9, the first light receiving element 41, the first filter 42, the first diaphragm member 43, and the first aperture. It includes a member 44.
The first light receiving element 41 is, for example, a photodiode, a thermopile, or the like, and outputs an electric signal (voltage) according to the intensity of the infrared rays to be received.
The first filter 42 is a bandpass filter arranged on the upstream side of the first light receiving element 41 and passing infrared rays in the first wavelength region λ1 among the infrared rays radiated from the object to be heated W.
The first diaphragm member 43 is arranged on the upstream side of the first filter 42 and has a pinhole for passing infrared rays.
The first ring member 44 is disposed upstream of the first diaphragm member 43, a circular hole of a predetermined size to pass infrared region closer to the optical axis L ₁₂ of the infrared rays reflected by the first optical element 60 ing.

The second light receiving system 50 constitutes a part of the temperature measuring light receiving sensor LS, and as shown in FIG. 9, the second light receiving element 51, the second filter 52, the second diaphragm member 53, and the second aperture. It includes a member 54.
The second light receiving element 51 is, for example, a photodiode, a thermopile, or the like, and outputs an electric signal (voltage) according to the intensity of the infrared rays to be received.
The second filter 52 is a bandpass filter arranged on the upstream side of the second light receiving element 51 and passing infrared rays in a second wavelength region λ2 different from the first wavelength region λ1 among the infrared rays radiated from the object W to be heated. is there.
The second diaphragm member 53 is arranged on the upstream side of the second filter 52 and has a pinhole for passing infrared rays.
The second aperture member 54 is arranged on the upstream side of the second diaphragm member 53, and includes a circular hole having a predetermined diameter so as to allow infrared rays in a region close to the optical axis L ₂₂ of the infrared rays reflected by the second optical element 70 to pass through. ing.

The first optical element 60 is a reflection mirror that forms a part of the temperature measuring optical element LE, and is a cylinder whose one end side is closed by using a resin material such as polycarbonate, as shown in FIGS. 9 and 10. The reflective surface 61 is formed in a shape and has aluminum vapor deposition on the surface on one end side.
As shown in FIGS. 9 and 12, the reflecting surface 61 has an ellipse having a first focal point f ₁₁ in the vicinity of the opening 1a and a second focal point f ₁₂ in the vicinity of the first filter 42, and the first focal point f ₁₁ and the second. rotate the axis line S1 around through the bifocal f ₁₂ forming part of the spheroid defined by.

The first optical element 60, as shown in FIG. 12, the optical axis _L 11 of the infrared IR ₁ passing through the openings 1a and transparent window 30 is emitted from the bottom area W1 of the heated object _{W, L 12} Functions as a central axis to lead to the first light receiving system 40.
Since the reflecting surface 61 is formed as a part of the rotating ellipsoidal surface in this way, the infrared IR ₁ can be effectively focused and guided to the first light receiving system 40.

The second optical element 70 is a reflection mirror that forms a part of the temperature measuring optical element LE, and is a cylinder whose one end side is closed by using a resin material such as polycarbonate, as shown in FIGS. 9 and 10. It is formed in a shape and has a reflective surface 71 having aluminum vapor deposition on the surface on one end side.
The reflecting surface 71, as shown in FIGS. 9 and 12, near the the ellipse having a second focus _{f 22} in the vicinity of the first focal point _{f 21} and the second filter 52 and the first focal point _{f 21} the openings 1a rotate the axis line S2 around through the bifocal f ₂₂ forming part of the spheroid defined by.

Then, as shown in FIG. 12, the second optical element 70 transmits the infrared IR ₂ radiated from the bottom region W2 of the object to be heated W and passes through the opening 1a and the translucent window 30, with the optical axes L ₂₁ and L _22. Functions as a central axis to lead to the second light receiving system 50.
Since the reflecting surface 71 is formed as a part of the rotating ellipsoidal surface in this way, the infrared IR ₂ can be effectively focused and guided to the second light receiving system 50.

As shown in FIG. 10, the determination light receiving sensor 80 includes a light receiving element 81, a filter 82, a diaphragm member 83, and a diameter member 84.
The light receiving element 81 is, for example, a photodiode, a thermopile, or the like, and outputs an electric signal (voltage) according to the intensity of the infrared rays to be received.
The filter 82 is arranged on the upstream side of the light receiving element 81, and is a band through which infrared rays radiated from the third wavelength region λ3 and infrared rays radiated from the infrared light source 100 among the infrared rays radiated from the flame 4a of the gas burner 4 as a heating source. It is a path filter.
The diaphragm member 83 is arranged on the upstream side of the filter 82 and has a pinhole for passing infrared rays.
The aperture member 84 is arranged on the upstream side of the diaphragm member 83, and has a circular hole having a predetermined diameter for passing infrared rays in a region close to the optical axis L ₃₂ and the optical axis L ₄₂ among the infrared rays reflected by the determination optical element 90. I have.

As shown in FIGS. 10 and 13, the determination optical element 90 is formed in a tubular shape with one end closed by using a resin material such as polycarbonate, and the first reflection is aluminum-deposited on the surface of one end. It includes a surface mirror 91 and a second reflection mirror 92.
As shown in FIGS. 10 and 13, the first reflection mirror 91 has an ellipse having a first focus f ₃₁ near the flame 4a and a second focus f ₃₂ near the filter 82, and the first focus f ₃₁ and the second. It is formed as a reflecting surface forming a part of the spheroid defined by rotating the axis line S3 around through the focus f _32.
As shown in FIGS. 10 and 14, the second reflection mirror 92 has an ellipse having a first focus f ₄₁ in the vicinity of the infrared light source 100 and a focus f ₄₂ (= f ₃₂ ) in the vicinity of the filter 82 as the first focus. It is formed as a reflecting surface that forms a part of a rotating elliptical surface defined by rotating around the axis S4 passing through f ₄₁ and the second focal point f ₄₂ .

Then, as shown in FIG. 13, the determination optical element 90 determines the infrared IR ₃ that is radiated from the flame 4a and passes through the opening 1a and the translucent window 30 with the optical axes L ₃₁ and L ₃₂ as the central axes. As shown in FIG. 14, the light receiving sensor for determination is guided to the light receiving sensor 80 for determination, and the infrared IR ₄ radiated from the infrared light source 100 and passing through the translucent window 30 is centered on the optical axes L ₄₁ and L _42. It works to lead to 80.
In this way, since the first reflection mirror 91 and the second reflection mirror 92 are each formed as a part of the rotating ellipsoidal surface, the infrared rays IR ₃ and IR ₄ are effectively focused and the light receiving sensor 80 for determination is used. Can lead to.
Further, since the first reflection mirror 91 and the second reflection mirror 92 are integrally formed as a single member, the number of parts can be reduced as compared with the case where they are formed separately, and the optical axis at the time of assembly can be reduced. Adjustment work such as alignment and assembly work can be simplified.

The infrared light source 100 is a filament light bulb that radiates infrared rays in a third wavelength region λ3 similar to the flame 4a, and is fixed to a fixed portion 21b on the outside of the first housing cover 21.
That is, the infrared light source 100 is fixed to the outside of the housing H and radiates the infrared IR ₄ into the housing H through the translucent window 30.
Then, when driven (on), the infrared light source 100 emits infrared IR ₄ toward the translucent window 30, and when not driven (off), the infrared light source 100 stops emitting infrared IR ₄ .
In the infrared rays in the various wavelength regions described above, the first wavelength region λ1 is, for example, 3.5 μm to 4.2 μm, the second wavelength region λ2 is, for example, 8.0 μm to 12.0 μm, and the third wavelength region. As λ3, for example, 4.0 μm to 5.0 μm is adopted.

The light-shielding plate 110 is formed of a substantially rectangular flat plate using an aluminum material or the like, and the wall surface is subjected to infrared absorption processing, is painted black, for example, and is fitted into the concave portion 11f as shown in FIGS. 7 and 8. , A convex portion 112 fitted into the concave portion 12f and a notch portion 113 are provided.
Then, the light-shielding plate 110 is arranged in the first region A1 of the housing body 10, and as shown in FIG. 12, from the infrared IR ₁ and the second optical element 70 toward the first light receiving system 40 from the first optical element 60. It functions to prevent mutual interference with the infrared IR ₂ directed toward the second light receiving system 50.
Further, in the light-shielding plate 110, as shown in FIGS. 10 and 14, the infrared IR ₄ radiated from the infrared light source 100 passes through the notch 113 and enters the second region A2 from the first region A1 through the through hole 12e. It functions so as to be guided by the determination optical element 90 (second reflection mirror 92).
As a result, the first light receiving element 41 and the second light receiving element 51 can detect the intensities of the infrared rays IR ₁ and IR ₂ with high accuracy, respectively, and the light receiving element 81 has the infrared rays IR ₃ and IR ₄ . The intensity can be detected with high accuracy.

In the above configuration, as shown in FIGS. 10, 12 to 14, the optical axes L ₃₂ and L ₄₂ between the determination light receiving sensor 80 and the determination optical element 90 are the temperature measuring light receiving sensor LS (first light receiving sensor). The extension direction is only about 90 degrees with respect to the optical axes L ₁₂ and L ₂₂ between the system 40, the second light receiving system 50) and the temperature measuring optical element LE (first optical element 60, second optical element 70). It is placed in a twisted position.
By arranging the optical axes L ₃₂ and L ₄₂ at twisted positions in this way, as shown in FIGS. 15 and 16, the optical axes L ₁₁ , L ₁₂ , the optical axes L ₂₁ , L ₂₂ , and the light The optical axes of the axes L ₃₁ , L ₃₂ , and the optical axes L ₄₁ , and L ₄₂ are arranged so that they do not overlap with each other, and the components are arranged while preventing mutual interference between the infrared IR ₁ , IR ₂ , IR ₃ , and IR _4. It can be arranged collectively, and the housing H can be downsized and the infrared detection unit U as a whole can be downsized.
The twisting angle is not limited to 90 degrees, and may be any other angle.

The circuit board 120 is mounted with various electronic components and circuits that perform drive control of the first light receiving element 41, the second light receiving element 51, the light receiving element 81, and the infrared light source 100, detection signal processing, arithmetic processing, determination processing, and the like. The first housing body 11 is fixed to the boss portion 11e with a screw or the like, and is covered with the fourth housing cover 24 to be protected.

Here, as shown in FIG. 17, the circuit board 120 includes a CPU 121 that controls various calculations, drive controls, determinations, and the like, a drive circuit 122 of the first light receiving element 41, a signal detection circuit 123, and a second light receiving element. 51 drive circuit 124 and signal detection circuit 125, light receiving element 81 drive circuit 126 and signal detection circuit 127, drive circuit 128 for controlling on / off of infrared light source 100, storage unit 129 for storing various information, heating It is provided with an interface circuit 130 that inputs and outputs various signals to and from a combustion control circuit of a cooking device.

The CPU 121 also functions as a determination unit for determining the closed state of the opening 1a and the dirty state of the translucent window 30 based on the output signal of the determination light receiving sensor 80.
That is, the determination unit determines the blocked state of the opening 1a based on the output of the determination light receiving sensor 80 that has received the infrared IR ₃ radiated from the flame 4a of the gas burner 4 as a heating source, and also an infrared light source. The dirty state of the translucent window 30 is determined based on the difference in the output signals output by the determination light receiving sensor 80 in each state of 100 on / off (presence or absence of light reception of infrared IR ₄ ).

The storage unit 129 stores various information previously obtained by experiments or the like.
For example, in order to calculate the temperature of the object to be heated W based on the output signals of the resistance temperature sensor LS (first light receiving element 41, second light receiving element 51), infrared rays are emitted from the object to be heated W. Data indicating the relationship between the ratio of the output value corresponding to the first wavelength region λ1 and the output value corresponding to the second wavelength region λ2 and the temperature of the object to be heated W output by the resistance temperature sensor LS is stored. ing.
Further, in order to determine the blocked state of the opening 1a based on the output signal of the light receiving sensor 80 for determination, the determination is made by receiving infrared radiation from the flame 4a of the gas burner 4 according to the degree of the blocked state of the opening 1a. Data on a threshold value for determining whether or not the temperature is normal, that is, whether or not the temperature can be measured normally is stored based on the output value output by the light receiving sensor 80 and the output value.
Further, in order to determine the dirty state of the translucent window 30 based on the output signal of the light receiving sensor 80 for determination, infrared rays are radiated from the infrared light source 100 according to the degree of the dirty state of the translucent window 30. Data on a threshold value for determining whether or not the temperature is normal, that is, whether or not the temperature can be measured normally is stored based on the output value output by the determination light receiving sensor 80 and the output value.

Next, the detection operation and the determination operation of the infrared detection unit U in the cooking apparatus will be described.
When the ignition operation is performed in the cooking apparatus, the first light receiving element 41, the second light receiving element 51, and the light receiving element 81 are driven in conjunction with the operation or in a timely manner thereafter.
Then, the first light receiving element 41 and the second light receiving element 51 output a signal according to the intensity of the infrared rays IR ₁ and IR ₂ radiated from the object to be heated.
Then, the temperature of the object to be heated W is calculated based on the output signals of the first light receiving element 41 and the second light receiving element 51. This temperature measurement process is continued during the operation of the cooking apparatus, and the heating state of the object to be heated W is monitored.

Further, the light receiving element 81 outputs a signal V according to the intensity of the infrared IR ₃ radiated from the flame 4a of the gas burner 4.
Then, the value of the output signal V is compared with the predetermined threshold value Vth, and if the value of the output signal V is equal to or higher than the threshold value Vth, it is determined that the opening 1a is not blocked and is normal, while the output signal V is determined to be normal. When the value is smaller than the threshold value Vth, the opening 1a is in a closed state and is determined to be abnormal.
This determination process is continued during the operation of the cooking apparatus, and the closed state of the opening 1a is monitored.

Then, the temperature measurement result and the determination result obtained by the infrared detection unit U are output from the interface circuit 130 to the combustion control circuit, the display notification circuit, and the like of the cooking device.
Here, if an abnormality occurs in the temperature measurement result or an abnormality occurs in the determination result of the closed state of the opening 1a, a control operation for shutting off the supply of fuel gas to stop combustion, or a display notification circuit A notification operation for notifying an abnormality is performed as appropriate.

On the other hand, when the heating / cooking apparatus is stopped, the light receiving element 81 is radiated from the natural world of the atmosphere in which the cooking apparatus is placed through the opening 1a in a state where the infrared light source 100 is not driven (off). and outputs a signal V ₁ depending on the intensity of the infrared ray.
Subsequently, the infrared light source 100 is driven (on), and the infrared IR ₄ is emitted from the infrared light source 100 toward the translucent window 30.
Then, the light receiving element 81 outputs the signal V ₂ according to the infrared rays from the natural world and the infrared intensity from the infrared light source 100.
After that, the infrared light source 100 is not driven.

Then, the value of the difference _V 2 -V ₁ of the output signal is compared with a predetermined threshold value Vth, if the value of the difference _V 2 -V ₁ of the output signal is threshold Vth or more, light-transmissive window 30 is not dirty it is determined to be normal, whereas the value of the difference V ₂ -V ₁ of the output signal when less than the threshold value Vth, it is determined that the transparent window 30 is abnormal in a state where dirty.
After that, when it is determined that there is an abnormality, the information is output from the interface circuit 130 to the display notification circuit of the cooking apparatus or the like, and the display notification circuit performs a notification operation to notify the abnormality.
The sequence of the detection operation and the determination operation is an example, and is not limited to this.

As described above, according to the infrared detection unit U having the above configuration, the infrared IR ₃ radiated from the heating source (gas burner 4) and the infrared light source 100 are radiated by one determination light receiving sensor 80. Since the infrared IR ₄ is detected, the number of parts can be reduced, the cost can be reduced, and the optical axis alignment work at the time of assembly can be simplified as compared with the case where two light receiving sensors are provided.
Further, since the temperature measuring light receiving sensor LS and the temperature measuring optical element LE and the judgment light receiving sensor 80 and the judgment optical element 90 are incorporated in one housing H, they are unitized separately. Compared with the case, the arrangement space in the housing 2 can be narrowed, and the cooking apparatus can be miniaturized.
Further, since the temperature measurement function and the determination function for fail-safe can be obtained only by mounting one infrared detection unit U inside the housing 2, the mounting work and the optical axis alignment work at the time of mounting are simplified. it can.

In the above embodiment, the case where the housing H is composed of the housing body 10 and the housing cover 20 is shown, but the present invention is not limited to this, and one place is provided as long as machinability and assembling property can be ensured. You may adopt the housing which provided only the cover.
In the above embodiment, as the housing body, the housing body 10 having a two-divided structure of the first housing body 11 and the second housing body 12 is shown, but the present invention is not limited to this, and the machinability and assembly are not limited thereto. An integrated housing body may be adopted as long as the property can be ensured.

In the above embodiment, as the determination optical element, the determination optical element 90 in which the first reflection mirror 91 and the second reflection mirror 92 are integrally formed is shown, but the present invention is not limited to this, and the determination optical elements 90 are separately formed. A determination optical element composed of two reflection mirrors formed in may be adopted.
In the above embodiment, the first reflection mirror 91 and the second reflection mirror 92 are shown to have a reflection surface forming a part of the rotating elliptical surface, but the present invention is not limited to this, and is emitted from a heating source. An optical element having another form may be adopted as long as it guides the infrared rays emitted from the infrared rays and the infrared rays emitted from the infrared light source to the light receiving sensor 80 for determination.

In the above embodiment, the first optical element 60 and the second optical element 70 are adopted as the temperature measuring optical element LE, but the present invention is not limited thereto, and the first light receiving system 40 and the second light receiving system 50 are used. One optical element that guides infrared rays may be adopted.
In the above embodiment, the case where the first light receiving system 40 and the second light receiving system 50 are adopted as the temperature measuring light receiving sensor LS is shown, but the present invention is not limited to this, and one light receiving element is adopted. , The configuration in which the two bandpass filters are selectively interchanged and arranged like the revolver mechanism may be adopted.
In the above embodiment, the gas burner 4 is shown as the heating source, but the present invention is not limited to this, and an electric heating type heater or the like may be adopted.

As described above, according to the infrared detection unit and the cooking apparatus of the present invention, whether or not the infrared detection can be performed normally while achieving simplification of assembly work, consolidation of parts, miniaturization, and the like. Since it can be determined, it can be used for cooking equipment such as gas stoves and electric stoves, and is also useful in other fields.

1 Top plate 1a Opening 4 Gas burner (heating source)
W Heated object H Housing 10 Housing body (housing)
20 Housing cover (housing)
A1 1st area A2 2nd area 30 Translucent window N Normal LS Temperature measurement light receiving sensor 41 1st light receiving element 51 2nd light receiving element LE Temperature measurement optical element 60 1st optical element 70 2nd optical element 80 For judgment Light receiving sensor 90 Judgment optical element 91 1st reflection mirror 92 2nd reflection mirror L ₃₂ , L ₄₂ Optical axis L ₁₂ , L ₂₂ Optical axis 100 Infrared light source 110 Light shielding plate 120 Circuit board 121 CPU (judgment unit)

Claims (16)

A housing with a translucent window oriented into a given opening,
A light receiving sensor for determination, which is fixed to the inside of the housing and for determining the closed state of the opening and the dirty state of the translucent window.
An infrared light source fixed to the outside of the housing and radiating infrared rays toward the translucent window,
Infrared rays fixed inside the housing and radiated from the heating source and passed through the opening and the translucent window are guided to the determination light receiving sensor, and are radiated from the infrared light source and passed through the translucent window. A judgment optical element that guides infrared rays to the judgment light receiving sensor,
Infrared detection unit, including. The determination optical element includes a first reflection mirror that guides infrared rays radiated from the heating source to the determination light receiving sensor, and a second reflection mirror that guides infrared rays radiated from the infrared light source to the determination light receiving sensor. And, including
The infrared detection unit according to claim 1. The first reflection mirror and the second reflection mirror are integrally formed as a single member.
The infrared detection unit according to claim 2. A temperature-measuring light-receiving sensor fixed to the inside of the housing and for measuring the temperature of the object to be heated by the heating source.
Further includes a temperature measuring optical element fixed inside the housing and guiding infrared rays radiated from the object to be heated and passing through the opening and the translucent window to the temperature measuring light receiving sensor.
The infrared detection unit according to claim 1 or 2. The optical axis between the determination light receiving sensor and the determination optical element is arranged at a twisted position with respect to the optical axis between the temperature measurement light receiving sensor and the temperature measurement optical element.
The infrared detection unit according to claim 4. The housing is
A partition wall that separates the first region where the temperature measuring light receiving sensor and the temperature measuring optical element are arranged and the second region where the determination light receiving sensor and the determination optical element are arranged.
A through hole formed in the partition wall so as to guide infrared rays radiated from the heating source and infrared rays radiated from the infrared light source from the first region to the determination optical element in the second region. including,
The infrared detection unit according to claim 4 or 5. The resistance temperature sensor has a first light receiving element that receives infrared rays in a first wavelength region radiated from the object to be heated and a second light receiving element that receives infrared rays in a second wavelength region radiated from the object to be heated. Including the light receiving element,
The infrared detection unit according to any one of claims 4 to 6, wherein the infrared detection unit is characterized. The temperature measuring optical element includes a first optical element corresponding to the first light receiving element and a second optical element corresponding to the second light receiving element.
The infrared detection unit according to claim 7. A light-shielding plate arranged inside the housing is provided in order to prevent mutual interference between the infrared rays from the first optical element toward the first light receiving element and the infrared rays from the second optical element toward the second light receiving element. Including more,
The infrared detection unit according to claim 8. The housing holds the determination light receiving sensor, the determination optical element, the temperature measurement light receiving sensor, the housing body holding the temperature measurement optical element, the translucent window, and the infrared light source. 1 Housing cover, including,
The infrared detection unit according to any one of claims 4 to 9. The housing body defines a first region in which the temperature measuring light receiving sensor and the temperature measuring optical element are arranged, and a second region in which the determination light receiving sensor and the determination optical element are arranged.
The first housing cover is assembled to the housing body so as to cover the first area.
The infrared detection unit according to claim 10. The housing includes a second housing cover that is assembled to the housing body so as to cover the second area.
The infrared detection unit according to claim 11. A determination unit for determining the closed state of the opening and the dirty state of the translucent window based on the output signal of the light receiving sensor for determination is further included.
The determination unit determines the closed state of the opening based on the output of the determination light receiving sensor that receives infrared rays radiated from the heating source.
The infrared detection unit according to any one of claims 1 to 13. The determination unit determines a dirty state of the translucent window based on the difference in output signals output by the determination light receiving sensor depending on whether the infrared light source is turned on or off.
The infrared detection unit according to claim 13. A top plate with a predetermined opening and
A heating source that heats the object to be heated placed above the top plate,
It is provided with an infrared detection unit arranged below the top plate and detecting infrared rays radiated from the object to be heated and passing through the opening or infrared rays radiated from the heating source and passing through the opening. It ’s a cooking device,
The infrared detection unit is the infrared detection unit according to any one of claims 1 to 14.
A cooking device characterized by that. The translucent window of the infrared detection unit is arranged in a region outside the vertically downward region of the opening in a state in which a normal passing through the center of the transmissive window is inclined toward the opening.
The cooking apparatus according to claim 15.

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