JP7269083B2 - Infrared detection unit and cooking device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an infrared detection unit that is applied to measure the temperature of an object to be heated using infrared rays, and in particular, to measure the temperature of an object to be heated such as a pot or frying pan in a cooking device such as a gas stove. In addition, 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 same.

As a conventional heat cooking device, a burner that heats a container placed on a trivet on a top plate, a translucent window that is fixed so as to block the opening of the top plate, and a translucent window that is placed in the housing An infrared intensity detector for detecting the intensity of infrared rays radiated from the container through the translucent window, a light receiving means for contamination determination that is arranged diagonally below the translucent window in the housing and detects the intensity of infrared rays radiated from the flame of the burner, etc. There is known a gas stove equipped with such an apparatus (for example, Patent Literature 1).

In this gas stove, since the opening of the top plate is blocked by the translucent window, it is possible to prevent spilled broth and solids from entering the housing, but since the translucent window is close to the flame, There is room for improvement in terms of heat resistance and durability of windows and adhesives.
On the other hand, if the translucent window is abolished and the opening of the top plate is left open, there is a risk that the spilled broth or solid matter may enter the housing and contaminate the surface of the infrared intensity detector. In this case, it is necessary to detect the dirtiness of the surface of the infrared intensity detector.
In addition, there is a risk that the opening may be blocked by solid matter or the like, blocking the optical path of the infrared rays. In this case, it is necessary to detect the blocked state of the opening.
Furthermore, in the above-mentioned gas stove, the light receiving means for contamination determination is provided separately from the infrared intensity detection part, so that each arrangement space is required, which complicates the assembly work, increases the number of work steps, and It causes an increase in body size.

JP 2013-204918 A

The present invention has been made in view of the above circumstances, and its object is to solve the conventional problems, simplify the assembly work, integrate parts, reduce the size, etc. Another object of the present invention is to provide an infrared detection unit and a cooking device that can determine whether or not infrared detection is normally performed.

The infrared detection unit of the present invention comprises a housing having a translucent window directed at a predetermined through opening, and a housing fixed inside the housing for determining the occlusion condition of the aperture and the dirty condition of the translucent window. A light-receiving sensor for determination, an infrared light source that is fixed outside the housing and emits infrared rays toward the translucent window, and an infrared ray that is radiated from a heating source that is fixed inside the housing and passes through the opening and the translucent window. an optical element for determination including a first reflecting mirror for guiding to a light receiving sensor for determination and a second reflecting mirror for guiding infrared rays emitted from an infrared light source and passing through a translucent window to the light receiving sensor for determination; A light-receiving sensor for temperature measurement for measuring the temperature of the object heated by the heating source, and infrared rays emitted from the object fixed inside the housing and passing through the opening and translucent window for temperature measurement and a temperature-measuring optical element leading to the light-receiving sensor .

In the infrared detection unit, the first reflecting mirror is a part of an ellipsoid of revolution defined by rotating an ellipse having two focal points in the vicinity of the heat source and in the vicinity of the light receiving sensor for judgment around an axis passing through the two focal points. The second reflecting mirror is an ellipsoid of revolution defined by rotating an ellipse having two focal points in the vicinity of the infrared light source and in the vicinity of the determination light receiving sensor around an axis passing through the two focal points A configuration may be adopted in which the reflecting surface is formed as a part of the .

In the infrared detection unit, the first reflection mirror and the second reflection mirror may be integrally formed as a single member.

In the above infrared detection unit , the translucent window may be arranged at an angle with respect to the housing so as to be arranged in a region out of the vertically lower region of the opening.

In the infrared detection unit, the optical axis between the light receiving sensor for determination and the optical element for determination 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. configuration may be adopted.

In the infrared detection unit, the housing includes 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 determining light receiving sensor and the determining optical element are arranged. , a through hole formed in the partition wall for guiding the infrared rays emitted from the heating source and the infrared rays emitted from the infrared light source from the first area to the determination optical element in the second area. good too.

In the above infrared detection unit, the light receiving sensor for temperature measurement includes a first light receiving element for receiving infrared rays in a first wavelength region emitted from the object to be heated, and an infrared light in a second wavelength region emitted by the object to be heated. You may employ|adopt the structure containing the 2nd light receiving element which carries out.

In the above infrared detection unit, the temperature measuring optical element may employ 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 disposed inside the housing to prevent mutual interference between infrared rays traveling from the first optical element to the first light receiving element and infrared rays traveling from the second optical element to the second light receiving element. A configuration may be employed that further includes

In the infrared detection unit, the housing includes a housing body that holds the light receiving sensor for determination, the optical element for determination, the light receiving sensor for temperature measurement, and the optical element for temperature measurement; Arrangements may be employed that include a housing cover.

In the infrared detection unit, 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 determining light receiving sensor and the determining optical element are arranged. , the first housing cover may be assembled to the housing body so as to cover the first region.

In the above infrared detection unit, the housing may employ a configuration including a second housing cover attached to the housing body so as to cover the second area.

The infrared detection unit further includes a judgment section for judging whether the opening is blocked or whether the translucent window is dirty based on the output signal of the light-receiving sensor for judgment, wherein the judgment section receives infrared rays emitted from the heating source. A configuration may be adopted in which the clogged state of the opening is determined based on the output of the light receiving sensor for determination.

In the above infrared detection unit, the determining section may determine the dirty state of the translucent window based on the difference between the output signals output by the light receiving sensor for determination when the infrared light source is turned on and off. .

The heat cooking apparatus of the present invention comprises a top plate having a predetermined opening, a heat source for heating an object to be heated placed above the top plate, and a heat source disposed below the top plate for radiating heat from the object to be heated. and an infrared detection unit for detecting infrared rays passing through the opening or infrared rays radiated from a heating source and passing through the opening, wherein the infrared detection unit is any of the above configurations. is adopted as an infrared detection unit.

In the cooking apparatus, the translucent window of the infrared detection unit is arranged in an inclined state so that the normal line passing through the center of the translucent window is directed toward the opening in a region outside the vertically lower region of the opening. , configuration may be employed.

According to the infrared detection unit and the cooking device having the above configuration, simplification of assembly work, integration of parts, miniaturization, etc. can be achieved, and it is possible to determine whether infrared detection is normally performed. can.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is an external perspective view showing one embodiment of a cooking device to which an infrared detection unit according to the present invention is applied; 1 is an external perspective view showing an embodiment of an infrared detection unit according to the present invention, and showing a positional relationship with respect to an opening of a top plate of the cooking apparatus shown in FIG. 1. FIG. FIG. 2 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 detection unit through an opening in the cooking apparatus shown in FIG. 1; FIG. 2 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 detection unit through an opening in the cooking apparatus shown in FIG. 1; 2 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 detection unit through an opening in the cooking apparatus shown in FIG. 1. FIG. FIG. 2 is a partial plan view showing a state in which infrared rays radiated from a heating source on a top plate are led to an infrared detection unit through an opening in the cooking apparatus shown in FIG. 1; FIG. 3 is an exploded perspective view of the infrared detection unit shown in FIG. 2 when it is exploded and viewed diagonally from above; FIG. 3 is an exploded perspective view of the infrared detection unit shown in FIG. 2 , viewed obliquely from below; FIG. 3 is a perspective cross-sectional view partially showing the housing of the infrared detection unit shown in FIG. FIG. 3 is a perspective cross-sectional view partially showing the housing of the infrared detection unit shown in FIG. FIG. 3 is an exploded perspective view of a housing body of the infrared detection unit shown in FIG. 2 , viewed obliquely from below; In the infrared detection unit shown in FIG. 2, infrared rays radiated from the object to be heated pass through the opening, the translucent window, and the optical elements for temperature measurement (first optical element, second optical element) to the light-receiving sensor for temperature measurement. It is a perspective view which shows the state led to (the 1st light receiving element, the 2nd light receiving element). 3 is 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 reflecting mirror) in the infrared detection unit shown in FIG. 2. FIG. is. 3 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 translucent window and an optical element for judgment (second reflection mirror) in the infrared detection unit shown in FIG. 2. FIG. . 14. It is a perspective view which shows the state which displayed together the infrared rays shown in FIG. 12, the infrared rays shown in FIG. 13, and the infrared rays shown in FIG. 16 is a perspective view of the state shown in FIG. 15 viewed from another angle; FIG. 1 is a block diagram showing a system of circuit boards included in an infrared detection unit according to the present invention; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.
As shown in FIG. 1, the heat cooking apparatus according to one embodiment includes a top plate 1 defining an opening 1a, a housing 2 closed by the top plate 1, and a pot or the like placed on the upper surface of the top plate 1. It has a trivet 3 on which an object W to be heated can be placed, a gas burner 4 as a heating source for burning gas, and an infrared detection unit U arranged in the housing 2 below the top plate 1 .
Furthermore, the cooking device includes a supply pipe for supplying a mixture of fuel gas and air to the gas burner 4, a gas nozzle provided upstream of the supply pipe, an adjustment valve for adjusting the flow rate of the fuel gas supplied to the gas nozzle, an adjustment A combustion control circuit for controlling a valve to adjust the amount of combustion of the gas burner 4 and a display/notification circuit for displaying and notifying various information are provided.

The top plate 1 is made of a metal material such as stainless steel, and the opening 1a is formed by punching the top plate 1 in a circular shape and penetrating the hole.
The gas burner 4 is a Bunsen combustion type external flame burner, and is adapted to eject flames 4a (see FIG. 5) from a plurality of flame ports arranged outward in an annular manner.

As shown in FIGS. 2, 7 and 8, the infrared detection unit U includes a housing body 10 as a housing H, a housing cover 20, a translucent window 30, a first light receiving system 40 and a second light receiving system 50. A light receiving sensor for temperature LS, a temperature measuring optical element LE including a first optical element 60 and a second optical element 70, a light receiving sensor for determination 80, an optical element for determination 90, an infrared light source 100, a light shielding plate 110, and a circuit board 120. It has
Then, the infrared detection unit U measures the temperature of the object W to be heated based on the intensity of the infrared rays emitted from the object W to be heated, as shown in FIGS. As shown in FIG. 13, the blockage state of the opening 1a is determined based on the intensity of infrared rays emitted from the flame 4a of the gas burner 4, and as shown in FIG. function to determine the contamination state of the translucent window 30 .

Here, the infrared detection unit U is fixed in the housing 2 of the cooking apparatus, and as shown in FIG. The translucent window 30 is arranged in an inclined state 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 a foreign matter such as boiling broth or solid matter enters the housing 2 through the opening 1a, the foreign matter falls directly onto the translucent window 30. Even if broth or the like splashes and adheres to the translucent window 30, it naturally drips along the slanted surface and can be suppressed from solidifying and staying on the surface of the translucent window 30.例文帳に追加

The housing body 10 is made 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.
The first housing body 11 has an inner wall painted black, and includes a multi-step fitting hole 11 a for fixing the first light receiving system 40 , a multi-step fitting hole 11 b for fixing the second light receiving system 50 , and a first optical element 60 . a fitting hole 11c for fixing the second optical element 70, a fitting hole 11d for fixing the second optical element 70, a boss portion 11e for fixing the circuit board 120, a concave portion 11f for attaching the light shielding plate 110, a joint surface 11g, cover joint portions 11h, 11i, 11j, and a fixing portion 11k fixed to the leg portion 2a of the housing 2. As shown in FIG.
The second housing body 12 has an inner wall painted black, and includes a multistage fitting hole 12a for fixing the light receiving sensor 80 for determination, a boss portion 12b for fixing the optical element 90 for determination, a joint surface 12c, a partition wall 12d, and a partition. It has a through hole 12e opened in the wall 12d, a concave portion 12f for mounting the light shielding plate 110, and a cover joint portion 12g.

Here, the housing body 10 is formed by joining the joint surface 12c of the second housing body 12 to the joint surface 11g and attaching it to the first housing body 11 with screws or the like.
In the housing body 10, the partition wall 12d serves as a boundary for the first area A1 where the temperature measuring light sensor LS and the temperature measuring optical element LE are arranged, and the judgment light receiving sensor 80 and the judgment optical element 90 are arranged. and a second area A2 to be defined.
In addition, the through hole 12e emits an infrared ray IR ₃ emitted from the flame 4a of the gas burner 4 as a heating source and an infrared ray IR ₄ emitted from the infrared light source 100 within the first area A1 to the second area A2. It is formed to lead to element 90 .

Thus, since the housing body 10 has a two-part structure of the first housing body 11 and the second housing body 12, machining is easy, and various parts can be easily assembled. .
In addition, a partition wall 12d is provided to provide a first area A1 where the temperature measuring light receiving sensor LS and the temperature measuring optical element LE are arranged and a second area A2 where the determining light receiving sensor 80 and the determining optical element 90 are arranged. By separating the infrared rays IR 1 and IR ₂ incident on the first light receiving element 41 and the second light receiving element 51 and the infrared rays IR ₃ and IR ₄ incident on the light receiving element 81, mutual interference is reliably prevented _. be able to.

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, as shown in FIGS.

The first housing cover 21 is made of an aluminum material or the like, has an inner wall that is processed to absorb infrared rays, and is painted, for example, black. It has a joint surface 21c that is joined to the cover joint portion 11h of the first housing body 11 .
In the first housing cover 21, the translucent window 30 is fixed to the edge portion 21a by an adhesive or the like, and the joint surface 21c is joined to the cover joint portion 11h in a state in which the infrared light source 100 is fixed to the fixing portion 21b. It is attached to the first housing body 11 with screws or the like so as to cover the first area A1, and prevents light from entering the first area A1 from the outside except for the area of the translucent window 30.

The second housing cover 22 is made of a resin material such as polyacetal, has an inner wall that is processed to absorb infrared rays, for example, painted black, and has a joint surface 22a.
The second housing cover 22, in a state in which the light receiving sensor 80 for determination and the optical element 90 for determination are assembled, has a joint surface 22a joined to the cover joint portion 12g, and is mounted on the second housing so as to cover the second area A2. It is attached to the body 12 with screws or the like, and prevents light from entering the second area A2 from the outside.

The third housing cover 23 is made of an aluminum material or the like, has an inner wall that is processed to absorb infrared rays, is painted black, for example, and has a joint surface 23a.
With the first optical element 60 and the second optical element 70 assembled, the third housing cover 23 is assembled to the first housing body 11 by screws or the like with the joint surface 23a joined to the cover joint portion 11i. , to prevent light from entering the housing H from the outside.

The fourth housing cover 24 is made of a resin material such as polyacetal, and has a joint surface 24a.
The fourth housing cover 24 is screwed to the first housing body 11 with the joint surface 24a joined to the cover joint portion 11j in a state in which the first light receiving system 40, the second light receiving system 50, and the circuit board 120 are assembled. etc. to cover and protect internal parts.

The translucent window 30 is formed in a substantially rectangular flat plate shape, as shown in FIGS. 2 and 7, 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 emitted from the object W to be heated, the flame 4a of the gas burner 4 and the third wavelength region λ3 emitted from the infrared light source 100 are used. A material that transmits at least the infrared rays of is appropriately selected.
The transmissive window 30 is fixed to the first housing cover 21 with an adhesive or the like with its outer edge area fitted into the edge portion 21a.

The first light-receiving system 40 constitutes a part of the light-receiving sensor LS for temperature measurement, and as shown in FIG. A member 44 is provided.
The first light receiving element 41 is, for example, a photodiode, a thermopile, or the like, and outputs an electric signal (voltage) corresponding to the intensity of received infrared rays.
The first filter 42 is a bandpass filter that is arranged upstream of the first light receiving element 41 and passes infrared rays in the first wavelength region λ1 among the infrared rays radiated from the object W to be heated.
The first aperture member 43 is arranged upstream of the first filter 42 and has a pinhole through which infrared rays pass.
The first aperture member 44 is arranged on the upstream side of the first diaphragm member 43 and has a circular hole with a predetermined diameter for passing infrared rays in a region near the optical axis _L12 among the infrared rays reflected by the first optical element 60. ing.

The second light-receiving system 50 constitutes a part of the light-receiving sensor LS for temperature measurement, and as shown in FIG. A member 54 is provided.
The second light receiving element 51 is, for example, a photodiode, a thermopile, or the like, and outputs an electric signal (voltage) corresponding to the intensity of received infrared rays.
The second filter 52 is arranged upstream of the second light-receiving element 51, and is a band-pass filter that passes 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. be.
The second throttle member 53 is arranged on the upstream side of the second filter 52 and has a pinhole through which infrared rays pass.
The second aperture member 54 is arranged on the upstream side of the second diaphragm member 53 and has a circular hole with a predetermined diameter for passing infrared rays in a region near the optical axis _L22 among the infrared rays reflected by the second optical element 70. ing.

The first optical element 60 is a reflecting mirror forming part of the temperature measuring optical element LE, and is made of a resin material such as polycarbonate as shown in FIGS. It has a reflecting surface 61 which is formed in a shape and is aluminum-deposited on the surface on one end side.
As shown in FIGS. 9 and 12, the reflecting surface 61 is an ellipse having a first focal point _f11 near the opening 1a and a second focal point _f12 near the first filter ₄₂ . It forms part of an ellipsoid of revolution defined by rotation about an axis S1 passing through two focal points _f12 .

Then, as shown in FIG. 12, the first optical element 60 directs the infrared rays _IR1 emitted from the bottom region W1 of the object W to be heated and passing through the opening 1a and the translucent window 30 to the optical axes _L11 and _L12 . is the central axis, and functions to lead to the first light receiving system 40 .
Since the reflecting surface 61 is formed as a part of the spheroid in this way, the infrared rays _IR1 can be effectively condensed and guided to the first light receiving system 40 .

The second optical element 70 is a reflecting mirror that constitutes a part of the temperature measuring optical element LE, and is made of a resin material such as polycarbonate as shown in FIGS. It has a reflecting surface 71 which is formed in a shape and is aluminum-deposited on the surface on one end side.
As shown in FIGS. 9 and 12, the reflecting surface 71 is an ellipse having a first focus _f21 near the opening 1a and a second focus _f22 near the second filter ₅₂ . It forms part of an ellipsoid of revolution defined by rotation about an axis S2 passing through two focal points _f22 .

Then, as shown in FIG. 12, the second optical element 70 directs the infrared rays IR2 emitted from the bottom region W2 of the object W to be heated and passing through the opening 1a and the translucent window ₃₀ to the optical axes _L21 and _L22 . is the central axis, and functions to lead to the second light receiving system 50 .
Since the reflecting surface 71 is formed as a part of the spheroid in this way, the infrared rays _IR2 can be effectively condensed 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, an aperture member 83, and an aperture member 84. As shown in FIG.
The light receiving element 81 is, for example, a photodiode, a thermopile, or the like, and outputs an electric signal (voltage) corresponding to the intensity of received infrared rays.
The filter 82 is arranged on the upstream side of the light receiving element 81, and is a band that passes infrared rays in the third wavelength region λ3 among infrared rays emitted from the flame 4a of the gas burner 4 as a heating source and infrared rays emitted from the infrared light source 100. It is a pass filter.
The throttle member 83 is arranged upstream of the filter 82 and has a pinhole through which infrared rays pass.
The aperture member 84 is arranged on the upstream side of the aperture member 83 and has a circular hole with a predetermined diameter for passing the infrared rays in the regions near the optical axis _L32 and the optical axis _L42 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 made of a resin material such as polycarbonate, and is formed in a tubular shape with one end side closed. A surface mirror 91 and a second reflecting mirror 92 are provided.
The first reflecting mirror 91 forms an ellipse having a first focus _f31 near the _flame 4a and a second focus _f32 near the filter 82, as shown in FIGS. It is formed as a reflecting surface forming a part of an ellipsoid of revolution defined by rotating about an axis S3 passing through the focal point _f32 .
As shown in FIGS. 10 and 14, the second reflecting mirror 92 forms an ellipse having a first focus f ₄₁ near the infrared light source 100 and a second focus f ₄₂ (=f ₃₂ ) near the filter 82 . It is formed as a reflecting surface forming a part of an ellipsoid of revolution defined by rotating around an axis S4 passing through the first focal point _f41 and the second focal point _f42 .

Then, as shown in FIG. 13, the determination optical element 90 uses the infrared rays IR ₃ emitted from the flame 4a and passing through the opening 1a and the translucent window 30 with the optical axes L ₃₁ and L ₃₂ as central axes for determination. As shown in FIG. 14, the infrared light IR ₄ emitted from the infrared light source 100 and passing through the light-transmitting window 30 is guided to the light receiving sensor 80 for determination, with the optical axes L ₄₁ and L ₄₂ as the central axes. It functions to lead to 80.
In this way, since the first reflecting mirror 91 and the second reflecting mirror 92 are each formed as a part of the ellipsoid of revolution, the infrared rays IR ₃ and IR ₄ are effectively condensed so that the light receiving sensor 80 for judgment is detected. can lead to
In addition, since the first reflecting mirror 91 and the second reflecting mirror 92 are integrally formed as a single member, the number of parts can be reduced compared to the case where they are formed separately. Adjustment work such as alignment, assembly work, etc. can be simplified.

The infrared light source 100 is a filament bulb that emits infrared light in the third wavelength region λ3, which is the same as the flame 4a, and is fixed to the fixing portion 21b on the outside of the first housing cover 21. As shown in FIG.
That is, the infrared light source 100 is fixed outside the housing H and emits infrared rays _IR4 into the housing H through the translucent window 30 .
When driven (turned on), the infrared light source 100 emits infrared rays _IR4 toward the translucent window 30, and when turned off (turned off), the infrared light source 100 stops emitting infrared rays _IR4 .
Incidentally, in the infrared rays of the above various wavelength regions, 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 λ3 is, for example, 4.0 μm to 5.0 μm.

The light shielding plate 110 is formed into a substantially rectangular flat plate using an aluminum material or the like, and the wall surface thereof is processed to absorb infrared rays, for example, painted black. As shown in FIGS. , a projection 112 fitted in the recess 12f, and a notch 113. As shown in FIG.
The light shielding plate 110 is arranged in the first area A1 _of the housing body 10, and as shown in FIG. It functions to prevent mutual interference with infrared rays _IR2 directed toward the second light receiving system 50 .
Further, as shown in FIGS. 10 and 14, the light shielding plate 110 passes infrared rays _IR4 emitted from the infrared light source 100 through the notch 113 from the first area A1 to the second area A2 through the through hole 12e. is guided to the optical element 90 (second reflecting mirror 92) for determination of the .
Thereby, the first light receiving element 41 and the second light receiving element 51 can detect the intensity of the infrared rays IR ₁ and IR ₂ with high accuracy, respectively, and the light receiving element 81 can detect the infrared rays IR ₃ and IR ₄ . Intensity can be detected with high accuracy.

In the above configuration, as shown in FIGS. 10 and 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 aligned with the temperature measuring light receiving sensor LS (first light receiving sensor). system 40, second light-receiving system 50) and temperature-measuring optical element LE (first optical element ₆₀ , second optical element ₇₀ ). placed in a twisted position.
By arranging the optical axes L ₃₂ and L ₄₂ at twisted positions in this way, the optical axes L ₁₁ and L ₁₂ , the optical axes L ₂₁ and L ₂₂ , the light The optical axes of the axes L ₃₁ and L ₃₂ and the optical axes L ₄₁ and L ₄₂ are arranged so as not to overlap each other to prevent mutual interference of the infrared rays IR ₁ , IR ₂ , IR ₃ and IR ₄ while the components are They can be collectively arranged, and the size reduction of the housing H and the size reduction of the infrared detection unit U as a whole can be achieved.
Note that the twist angle is not limited to 90 degrees, and other angles may be used.

Various electronic components and circuits are mounted on the circuit board 120 for driving 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. It is covered and protected by the fourth housing cover 24 while being fixed to the boss portion 11e of the first housing body 11 with screws or the like.

Here, as shown in FIG. 17, the circuit board 120 includes a CPU 121 that controls various operations such as calculation, drive control, and determination, a drive circuit 122 and a signal detection circuit 123 for the first light receiving element 41, a second light receiving element, 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 An interface circuit 130 is provided for inputting and outputting various signals with the combustion control circuit of the cooking apparatus.

The CPU 121 also functions as a determination unit that determines whether the opening 1a is blocked and whether the translucent window 30 is dirty based on the output signal of the light-receiving sensor 80 for determination.
That is, the judging section judges whether or not the opening 1a is clogged based on the output of the judging light receiving sensor 80 which receives the infrared rays _IR3 radiated from the flame 4a of the gas burner 4 as a heating source. The contamination state of the translucent window 30 is determined based on the difference in the output signal output from the determination light receiving sensor 80 in each ON/OFF state of 100 (whether or not infrared rays IR ₄ are received).

The storage unit 129 stores various information obtained in advance through experiments or the like.
For example, in order to calculate the temperature of the object W to be heated based on the output signal of the light receiving sensor LS for temperature measurement (the first light receiving element 41, the second light receiving element 51), the infrared radiation from the object W to be heated is received. 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 output from the light receiving sensor LS for temperature measurement and the temperature of the object W to be heated is stored. ing.
In addition, in order to determine whether or not the opening 1a is blocked based on the output signal of the light-receiving sensor 80 for determination, infrared radiation from the flame 4a of the gas burner 4 is received and determined according to the degree of the blocked state of the opening 1a. Data regarding an output value output from the light receiving sensor 80 and a threshold value for determining whether or not the temperature is normally measured based on the output value are stored.
Furthermore, in order to determine the contamination state of the light-transmitting window 30 based on the output signal of the determination light-receiving sensor 80, infrared radiation from the infrared light source 100 is received according to the degree of contamination of the light-transmitting window 30. An output value output from the determination light-receiving sensor 80 and data relating to a threshold value for determining whether or not the temperature is normally measured based on the output value are stored.

Next, the detection operation and determination operation of the infrared detection unit U in the above heat cooking apparatus will be described.
In the cooking device, when the ignition operation is performed, 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 at appropriate times thereafter.
The first light receiving element 41 and the second light receiving element 51 output signals according to the intensity of the infrared rays IR ₁ and IR ₂ emitted from the object W to be heated.
Then, the temperature of the object W to be heated 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 while the cooking apparatus is in operation, and the heating state of the object W to be heated is monitored.

Also, the light receiving element 81 outputs a signal V according to the intensity of the infrared rays _IR3 radiated from the flame 4a of the gas burner 4. FIG.
Then, the value of the output signal V is compared with a predetermined threshold value Vth. If the value is smaller than the threshold value Vth, it is determined that the opening 1a is closed and abnormal.
This determination process is continued while the cooking apparatus is in operation, and the clogged state of the opening 1a is monitored.

The temperature measurement results and determination results 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 heat cooking apparatus.
Here, when an abnormality occurs in the temperature measurement result or when an abnormality occurs in the determination result of the clogged state of the opening 1a, the control operation to cut off the supply of the fuel gas and stop the combustion, or the display notification circuit , a notification operation is performed to appropriately notify the abnormality.

On the other hand, when the cooking device is stopped, the light receiving element 81 emits light from the natural environment in which the cooking device is placed through the opening 1a while the infrared light source 100 is not driven (OFF). A signal _V1 is output according to the intensity of the infrared rays.
Subsequently, the infrared light source 100 is driven (turned on), and infrared light _IR4 is emitted from the infrared light source 100 toward the translucent window 30 .
The light receiving element 81 outputs a signal _V2 according to the intensity of the infrared rays from the natural world and the infrared rays from the infrared light source 100 .
After that, the infrared light source 100 is deactivated.

Then, the value of the output signal difference V ₂ −V ₁ is compared with a predetermined threshold value Vth, and if the value of the output signal difference V ₂ −V ₁ is equal to or greater than the threshold value Vth, the translucent window 30 is not contaminated. On the other hand, if the output signal difference V ₂ -V ₁ is smaller than the threshold value Vth, the translucent window 30 is judged to be dirty and abnormal.
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 or the like of the heat cooking apparatus, and the display/notification circuit performs an abnormality notification operation.
Note that the sequence of the detection operation and determination operation described above is merely an example, and the present invention is not limited to this.

As described above, according to the infrared detection unit U configured as described above, one determination light-receiving sensor 80 detects infrared rays IR ₃ emitted from the heating source (gas burner 4) and infrared rays IR 3 emitted from the infrared light source 100. Since infrared rays _IR4 are detected, it is possible to reduce the number of parts, reduce the cost, and simplify the optical axis alignment work at the time of assembly, compared with the case where two light receiving sensors are provided.
In addition, since the light receiving sensor LS for temperature measurement and the optical element LE for temperature measurement and the light receiving sensor 80 for determination and the optical element 90 for determination are incorporated in one housing H, they are separately unitized. Compared to the case, the arrangement space in the housing 2 can be narrowed, and the cooking device can be miniaturized.
Furthermore, just by installing one infrared detection unit U in the housing 2, it is possible to obtain the temperature measurement function and judgment function for fail-safe, so the installation work and the optical axis alignment work at the time of installation are simplified. can.

In the above embodiment, the case where the housing H is composed of the housing body 10 and the housing cover 20 has been shown, but the present invention is not limited to this, and as long as the machinability and assembling property can be ensured, the housing H can be provided at only one location. A housing having only a cover may be employed.
In the above embodiment, the housing body 10 having the two-part structure of the first housing body 11 and the second housing body 12 is shown as the housing body. A one-piece housing body may be adopted as long as it is possible to ensure the performance.

In the above-described embodiment, the determination optical element 90 in which the first reflection mirror 91 and the second reflection mirror 92 are integrally formed is shown as the determination optical element. A determination optical element consisting of two reflecting mirrors formed on the surface may be employed.
In the above embodiment, the first reflecting mirror 91 and the second reflecting mirror 92 have reflecting surfaces forming a part of the ellipsoid of revolution. As long as it guides the infrared rays emitted from the infrared light source and the infrared rays emitted from the infrared light source to the determination light receiving sensor 80, optical elements having other forms may be adopted.

In the above embodiment, the first optical element 60 and the second optical element 70 are used as the temperature measuring optical element LE, but the present invention is not limited to this, and the first light receiving system 40 and the second light receiving system 50 A single optical element may be employed to direct the infrared radiation to the
In the above embodiment, the first light receiving system 40 and the second light receiving system 50 are used as the light receiving sensor LS for temperature measurement. , a configuration in which two bandpass filters are arranged selectively interchangeably like a revolver mechanism may be employed.
In the above embodiment, the gas burner 4 is used as the heat source, but the heat source is not limited to this, and an electric heater or the like may be employed.

As described above, according to the infrared detection unit and the cooking apparatus of the present invention, it is possible to simplify the assembly work, integrate the parts, reduce the size, etc. Since it is possible to determine whether or not it is, it is useful not only for cooking devices such as gas stoves and electric stoves, but also in other fields.

1 top plate 1a opening 4 gas burner (heating source)
W object to be heated H housing 10 housing body (housing)
20 housing cover (housing)
A1 First area A2 Second area 30 Translucent window N Normal line LS Temperature measuring light receiving sensor 41 First light receiving element 51 Second light receiving element LE Temperature measuring optical element 60 First optical element 70 Second optical element 80 For determination Light receiving sensor 90 Judgment optical element 91 First reflection mirror 92 Second reflection mirrors _L32 , _L42 Optical axes _L12 , _L22 Optical axis 100 Infrared light source 110 Light shielding plate 120 Circuit board 121 CPU (judgment unit)

Claims (16)

a housing having a translucent window directed to a predetermined through opening;
a determining light-receiving sensor fixed inside the housing for determining a blocked state of the opening and a dirty state of the translucent window;
an infrared light source fixed outside the housing and emitting infrared rays toward the translucent window;
a first reflecting mirror fixed inside the housing for guiding infrared rays emitted from a heating source and passing through the opening and the translucent window to the light-receiving sensor for judgment and the translucent light emitted from the infrared light source an optical element for determination including a second reflecting mirror that guides infrared rays passing through the window to the light receiving sensor for determination;
a temperature-measuring light-receiving sensor fixed inside the housing for measuring the temperature of an object to be heated by the heating source;
a temperature-measuring optical element fixed inside the housing for guiding infrared rays emitted from the object to be heated and passing through the opening and the translucent window to the temperature-measuring light-receiving sensor;
Infrared detection unit, including. The first reflecting mirror forms part of an ellipsoid of revolution defined by rotating an ellipse having two focal points in the vicinity of the heat source and in the vicinity of the light-receiving sensor for determination around an axis passing through the two focal points . formed as a reflective surface,
The second reflecting mirror partially rotates an ellipsoid of revolution defined by rotating an ellipse having two focal points in the vicinity of the infrared light source and in the vicinity of the determination light receiving sensor around an axis passing through the two focal points . formed as a reflective surface,
The infrared detection unit according to claim 1, characterized in that: The first reflecting mirror and the second reflecting mirror are integrally formed as a single member,
The infrared detection unit according to claim 1 or 2, characterized in that: The light-transmitting window is arranged at an angle with respect to the housing so as to be arranged in an area outside the area vertically below the opening.
The infrared detection unit according to any one of claims 1 to 3, characterized in that: The optical axis between the light receiving sensor for determination and the optical element for determination 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.
The infrared detection unit according to any one of claims 1 to 4, characterized in that: The housing is
a partition wall separating 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 determining light receiving sensor and the determining optical element are arranged;
a through hole formed in the partition wall for guiding infrared rays emitted from the heating source and infrared rays emitted from the infrared light source from the first region to the optical element for determination in the second region; including,
The infrared detection unit according to any one of claims 1 to 5, characterized in that: The temperature-measuring light-receiving sensor includes a first light-receiving element that receives infrared rays in a first wavelength region emitted from the object to be heated, and a second light-receiving element that receives infrared rays in a second wavelength region emitted from the object to be heated. a light receiving element,
The infrared detection unit according to any one of claims 1 to 6, characterized in that: 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, characterized by: In order to prevent mutual interference between infrared rays traveling from the first optical element to the first light receiving element and infrared rays traveling from the second optical element to the second light receiving element, a light shielding plate disposed inside the housing is provided. further including,
The infrared detection unit according to claim 8, characterized in that: The housing includes a housing body that holds the light-receiving sensor for determination, the optical element for determination, the light-receiving sensor for temperature measurement, and the optical element for temperature measurement; 1 housing cover;
The infrared detection unit according to any one of claims 1 to 9, characterized in that: 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 determining light receiving sensor and the determining optical element are arranged,
The first housing cover is assembled to the housing body so as to cover the first region.
The infrared detection unit according to claim 10, characterized in that: The housing includes a second housing cover attached to the housing body so as to cover the second region,
The infrared detection unit according to claim 11, characterized by: further comprising a determination unit that determines a blocked state of the opening and a dirty state of the translucent window based on an output signal of the light receiving sensor for determination;
The determination unit determines whether the opening is blocked based on the output of the light receiving sensor for determination that receives infrared rays emitted from the heating source.
The infrared detection unit according to any one of claims 1 to 12 , characterized in that: The determination unit determines the dirty state of the translucent window based on a difference in output signals output from the light receiving sensor for determination when the infrared light source is turned on/off.
14. The infrared detection unit according to claim 13, characterized by: a top plate having a predetermined opening;
a heat source for heating the object to be heated placed above the top plate;
an infrared detection unit disposed below the top plate for 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. A heating and 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: The light-transmitting window of the infrared detection unit is arranged in an inclined state so that a normal line passing through the center of the light-transmitting window is directed toward the opening in a region outside the vertically downward region of the opening.
16. The cooking device according to claim 15, characterized by:

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