JP2004108707A - Weight sensor and heating cookware using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To allow a user to perform the optimum heating cooking of foods by simple operation by an automatic heating cooking function based on weight and position information of foods in a heating cookware. <P>SOLUTION: This heating cookware is provided with a heating chamber 2 storing foods 4, a magnetron 5 heating the foods 4, a rotary antenna 7 stirring electromagnetic wave, and a food loading base 3 loading the foods 4. A weight sensor 30 is provided below the food loading base 3. The food loading base 3 and a movable electrode 33 part of the weight sensor 30 are rigidly connected by a support member 17. It is provided with a function detecting weight information and position information of the foods 4 on the food loading base 3 by using respective electrostatic capacity signals between each fixed electrode 34 and a movable electrode 33 divided into a plurality of parts. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a capacitance-type weight sensor and a cooking device using the sensor, for example, a microwave oven or an electronic microwave oven.
[0002]
[Prior art]
In a turntable type heating cooker that rotates a table serving as a food mounting table to uniformly irradiate foods with electromagnetic waves from a magnetron installed at a predetermined position, Japanese Patent Laid-Open No. 8-320123 discloses a method for detecting the weight of foods. US Patent No. 6,064,098, a capacitance sensor having a movable electrode and a fixed electrode having a fixed electrode as disclosed in Japanese Patent Application Publication was used to detect the change in the gap between the electrodes as the capacitance due to the weight of the food. . Further, as disclosed in Japanese Patent Application Laid-Open No. 2000-104928, a projection is provided at the center of the movable electrode, and the projection receives a pressure due to the weight of the food.
[0003]
[Problems to be solved by the invention]
In the above-mentioned prior art JP-A-8-320123, since a pair of movable electrodes and a fixed electrode are used, the weight information of the food placed on the table can be detected, but the position information of the food is detected. There was a problem that could not be done.
[0004]
In Japanese Patent Application Laid-Open No. 2000-104928, since the pressing by the weight of the food acts as a point contact state on the projection provided at the center of the movable electrode, the gap between the fixed electrode and the movable electrode changes uniformly. I do. Therefore, the gap between the fixed electrode and the movable electrode is always substantially parallel. There has been a problem that it is impossible to detect a change in the sensor signal due to the position of the food on the table.
[0005]
The present invention is to solve at least one of the above problems.
[0006]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the present invention provides a capacitance-type weight sensor including a movable electrode and a fixed electrode opposed to the movable electrode. And a static capacitance signal between the fixed electrode.
[0007]
Also, a heating chamber for storing the food, a magnetron for heating the food, a waveguide for guiding electromagnetic waves, a rotating antenna for stirring the electromagnetic waves, a rotating antenna motor for driving the rotating antenna, and a food for placing the food. In a heating cooker provided with a mounting table, the weight sensor is provided below the food mounting table, and the food mounting table and the movable electrode portion of the weight sensor are rigidly connected by a support member, and each of the fixed electrodes divided into a plurality of movable electrodes is movable. The function of detecting the weight information and the position information of the food on the food mounting table by using the respective capacitance signals between the electrodes is provided.
[0008]
In a heating cooker having a heating chamber for storing food, a magnetron for heating the food, and a rotary food mounting table for mounting the food, the weight sensor is provided below the rotary food mounting table, and the rotary food storage is provided. The weight information and position of the food on the rotating food mounting table by rigidly connecting the mounting table and the movable electrode section of the weight sensor with a support member, and using the respective capacitance signals between each fixed electrode and the movable electrode divided into a plurality. It has a function of detecting information.
[0009]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the drawings.
[0010]
FIG. 1 shows a main structure of a turntableless microwave oven 1 according to an embodiment of the present invention and a system configuration of detection and control. The internal structure is divided into a heating chamber 2 for storing the food 4 to be cooked, and a machine room 14 provided on a side surface (right side in the figure) of the heating chamber 4.
[0011]
The heating room 2 has a heating room housing 12 in which left and right side surfaces, a back surface and a ceiling surface, and a bottom surface are integrally formed of a thin plate-like steel material. The food 4 has a door (not shown) made of glass and a thin steel plate provided with a large number of small holes in a punching shape so as not to transmit electromagnetic waves to the outside.
[0012]
Further, a rectangular plate-shaped food mounting table 3 (hereinafter, referred to as a table) on which the food 4 is mounted is provided on the bottom plate of the heating chamber housing 12 with the outer peripheral side surface of the table 3 made of silicon rubber, fluorine rubber or the like. It is sealed by a seal member 13 made of an elastic member and is elastically supported. Reference numeral 12a denotes an electromagnetic wave stirring chamber which is a space provided between the table 3 and the lower portion of the bottom plate.
[0013]
The machine room 14 is located on the side of the heating room 2, and the inside thereof is separated by a thin steel plate of the heating room housing 12 so as to block thermal or electromagnetic waves. Inside the machine room 14, a magnetron 5 for generating electromagnetic waves necessary for electromagnetic heating of the food 4, a heating control circuit 16 for controlling the electromagnetic waves from the magnetron 5, and air cooling for cooling each electronic component and circuit components A fan (not shown), an infrared temperature sensor 21 for detecting temperature information of the food 4 during the heating process, a posture control means 22 of the infrared temperature sensor 21, and the like are housed therein.
[0014]
The electromagnetic wave generated from the magnetron 5 provided in the machine room 14 enters the electromagnetic wave stirring chamber 12a via the hole 12a1 provided at the bottom of the electromagnetic wave stirring chamber 12a through the cylindrical waveguide 6 made of a thin steel plate. From here, the light propagates through the table 3 into the heating chamber 2. The electromagnetic wave stirring chamber 12a below the table 3 is provided with a rotating antenna 7 for stirring electromagnetic waves from the waveguide 6 and irradiating the food 4 with the rotating antenna 7. The rotating antenna 7 is provided outside the waveguide 6. It is driven via a rotating shaft 8 by a rotating antenna motor 9 provided.
[0015]
In the present embodiment, the weight sensor 30 for detecting the weight and the position information of the food 4 is provided at substantially the lower center of the table 3 and outside the waveguide 6. The weight information and the position information of the food 4 on the weight sensor 30 and the table 3 will be described in detail later, and are transmitted as pressure directly to the weight sensor 30 via the support member 17 connected to the table 3. .
[0016]
The heating cooker according to the present embodiment performs optimal cooking of the food 4 based on information detected by the weight sensor 30. In FIG. 1, the flow of signals from the weight sensor 30 to the heating control circuit 16 and the flow of heating control from the heating control circuit 16 to specific heating means are indicated by dotted arrows. The food heating means according to the embodiment includes a magnetron 5 for generating an electromagnetic wave, a rotating antenna 7 for irradiating the electromagnetic wave to the food 4, and a posture control means 22 of an infrared temperature sensor 21 for detecting temperature information of the food 4 in the cooking process. It is.
[0017]
A specific flow of the heating control will be described. The user places the food 4 to be cooked on the table 3 in the heating chamber 2, closes a door (not shown), and starts measuring the weight and position of the food 4 by the weight sensor 30 (operation principle). The detected signal is sent to the heating control circuit 16.
[0018]
When the user operates a button (not shown) for starting heating and cooking, the magnetron 5 operates. Since the weight of the food 4 is detected by the weight sensor 30, the cooking time based on the output of the magnetron 5 can be predicted, so that the output time of the magnetron 5 can be controlled.
[0019]
The magnitude of the output of the magnetron 5 may be controlled over time. Further, since the position information of the food 4 on the table 3 is detected, if the electromagnetic wave intensity distribution on the table 3 according to the position of the rotary antenna 7 is stored in a database in advance, the food 4 can be concentratedly heated. . Specifically, it is preferable to perform rotation control for controlling the electromagnetic wave concentrated irradiation unit of the rotating antenna 7 based on the position of the food 4. More specifically, the control is such as controlling the rotation speed of the rotating antenna 7 (variable) and temporarily stopping the rotation.
[0020]
Further, by controlling the infrared temperature sensor 21 for detecting the temperature of the food 4 based on the position information of the food 4 toward the food 4, detection of a useless space (a place without the food 4) can be omitted. 4 improves the accuracy of temperature detection and enables real-time detection.
[0021]
The temperature information of the food 4 obtained here may be fed back to the control of the magnetron 5 and the rotating antenna 7.
[0022]
Hereinafter, a specific structure and operation relating to the detection of the weight and the position of the food 4 will be described with reference to FIG.
[0023]
FIG. 2 is a cross-sectional view showing the structure of the weight sensor 30 of the heating cooker shown in FIG. 1, which is an embodiment of the present invention, and its peripheral structure. The side surface of the table 3 on which the food 4 is placed is elastically supported by the heating chamber housing 12 by a sealing member 13 made of an elastic member such as silicon rubber or fluorine rubber. Thus, the table 3 can be freely moved within the elastic deformation by the seal member 13, and the heating chamber 2 and the electromagnetic wave stirring chamber 12a below the table 3 are completely sealed by the table 3 and the seal member 13. . This is to prevent the food 4 placed in the heating chamber 2 from leaking into the waveguide 6 via the hole 12a1 of the electromagnetic wave stirring chamber 12a (for example, when the food 4 is spilled).
[0024]
A bar-shaped support member 17 is attached to the lower portion of the center of the table 3, and the weight of the table 3 and the food 4 placed on the table 3 is directly transmitted to the weight sensor 30 by the support member 17 as pressure. It has a structure. It is most preferable that the connecting portion 10 of the support member 17 and the table 3 be rigidly connected in order to transmit the weight information and the position information of the food 4 without loss. When the tolerance of the accuracy is wide, contact coupling by pressing may be used.
[0025]
Since the support member 17 is in the electromagnetic wave stirring chamber 12a or the waveguide 6, it is preferable to use a non-metallic material so as not to affect the distribution of the electromagnetic wave, and further use a ceramic material or the like having excellent heat resistance and strength. . The weight sensor 30 is provided substantially below the center of the table 3 and outside the waveguide 6. In this embodiment, it is provided outside the rotary antenna motor 9.
[0026]
In this embodiment, a turntableless heating cooker having a rotary antenna 7 for stirring electromagnetic waves generated from a magnetron 5 installed in a machine room 14 in a waveguide 6 below an electromagnetic wave stirring chamber 12a is embodied. Structure.
[0027]
The information of the food 4 is transmitted to the weight sensor 30 via the rotating antenna 7 and the rotating antenna motor 9 by the supporting member 17 provided at the lower portion of the center of the table 3. A through-hole 8a was provided in each of the antennas so as to be able to penetrate a rotary antenna motor 9 for rotatingly driving the antenna 7, thereby forming a hollow shaft structure.
[0028]
Thereby, the information of the food 4 can be directly transmitted to the weight sensor 30 via the support member 17 provided on the table 3 without affecting the installation restriction of the rotating antenna 7. The support member 17 can transmit weight information to the weight sensor 30 without loss of information due to contact frictional force or the like by having a non-contact structure with the rotating shaft 8 and the rotating antenna motor 9.
[0029]
Here, grease (not shown) or the like may be injected into the space around the support member 17 as a sliding lubricant in order to avoid friction at the time of emergency contact.
[0030]
The feature of this embodiment is that one weight sensor 30 detects the weight information of the food 4 placed on the table 3 and the position information of the food 4 on the table 3.
[0031]
Next, a specific structure of the weight sensor 30 will be described with reference to FIG.
[0032]
FIG. 3 shows a cross section of the weight sensor 30 part. The weight sensor 30 includes a fixed electrode 34 provided on a substrate 32 on which circuit components and the like are mounted, and a flat spring (hereinafter, referred to as a sensor spring 31) fixed on the substrate 32 with a fixing auxiliary member 36 such as a screw. The movable electrode 33 which is a part (a central part in the embodiment) is provided.
[0033]
The fixed electrode 34 and the movable electrode 33 maintain a predetermined gap and form opposing surfaces substantially in parallel. A hole 32a is formed in the center of the substrate 32 to penetrate the support member 17 for transmitting weight information of the food 4 and the like. The support member 17 penetrates the substrate 32 in a non-contact state from the upper part (table 3) in the figure. Then, the movable electrode portion 33 of the sensor spring 31 can be pressed.
[0034]
In a general capacitance type sensor, the gap between the fixed electrode 34 and the movable electrode 33 changes due to the pressing. From the change in the gap between the movable electrode 33 and the fixed electrode 34, the amount of displacement or force (weight) due to pressing is detected by the change in capacitance.
[0035]
In the present embodiment, the information of the food 4 on the table 3 and the mounting position of the food 4 on the table 3 are detected by the pressing force by using such a capacitance type sensor. The connection part of the sensor spring 31 which becomes the electrode 33 was completely fixed.
[0036]
As a fixing method, a fixing auxiliary member 36 such as a screw may be used as shown in FIG. Further, the support member 17 integrated with the sensor spring 31 may be configured.
[0037]
With such a configuration, when the food 4 is placed on the end of the table 3 shown in FIG. 2, a moment force acts on the support member 17, and the movable electrode 33 of the sensor spring 31 fixed to the support member 17 is tilted. While moving in the vertical direction, the gap between the fixed electrode 34 and the movable electrode 33 changes.
[0038]
Hereinafter, the principle of detecting the mounting position of the food 4 on the table 3 by the structure of the weight sensor 30 will be described using a specific sensor spring 31, a movable electrode 33 structure and a fixed electrode structure 34 provided on a substrate 32. .
[0039]
The sensor spring 31 shown in FIG. 4 is made of a flat spring steel material, and has a structure in which a movable electrode portion 33 at the center is supported by four beams 33a. The sensor spring 31 is fixed to the outside (for example, the substrate 32) by screws (not shown) at the outer ends of the four beams 33a. As shown in the cross-sectional view taken along the line AA in the figure, bent portions 35 are provided at the four beams 33a, respectively. As shown in FIG. 3, when a moment is applied to the support member 17 fixed to the center of the movable electrode 33 due to the mounting position of the food 4 on the table 3, a difference in deformation of each bent portion 35 (four places in the figure) causes a difference. The movable electrode section 33 moves in the up and down direction while having an inclination. That is, if the inclination direction of the movable electrode 33 at this time can be detected, the mounting position (direction) of the food 4 on the table 3 can also be detected.
[0040]
FIG. 5 shows a structure of the fixed electrode 34 according to the present embodiment corresponding to the movable electrode 33 shown in FIG. 4 for detecting the weight information and the position information of the food 4 as the capacitance type weight sensor 30.
[0041]
FIG. 5 shows a substrate 32 provided with divided fixed electrodes 34 and mounted with circuit components necessary for the capacitance type weight sensor 30. The present invention relates to the structure of the fixed electrode 34, and shows only the pattern of the fixed electrode 34, and does not show circuit components and the like.
[0042]
The structure of the fixed electrode 34 according to the present embodiment has the same outer shape and size as the movable electrode unit 33 shown in FIG. 4, and the support member 17 for transmitting the weight information of the food 4 from the table 3 to the sensor spring 31 in the center. The holes 32P and 34P are provided in the substrate 32 and the fixed electrode 34 so that the holes 32P and 34P can pass through.
[0043]
The fixed electrode 34 was divided into four regions (34a to 34d). Thus, the capacitance-type weight sensor 30 in which four pieces of information can be obtained by the four divided fixed electrodes 34 for one movable electrode 33 provided in the sensor spring 31 was configured.
[0044]
In other words, the weight sensor 30 can provide an output corresponding to the number of divisions of the fixed electrode 34 by one weight sensor 30.
[0045]
As described above, the moment force acts on the support member 17 fixed to the sensor spring 31 depending on the mounting position of the food 4 on the table 3, and the movable electrode 33 of the sensor spring 31 has a fixed electrode while being inclined. The gap between 34 changes. Thus, the direction of the moment force applied to the support member 17 can be detected by the amount of change in the gap between each of the four fixed electrodes 34 and the movable electrode 33 according to the embodiment. That is, the placement position of the food 4 on the table 3 can be detected. The total weight of the food 4 can also be detected by summing the output signals between the divided electrodes.
[0046]
FIG. 6 shows the principle of detecting the position of the food 4 by the weight sensor 30 according to the present embodiment when the food 4 is placed at a biased position on the table 3. If the food 4 is placed on the right side of the table 3, the outer peripheral side surface of the table 3 is elastically supported by the seal member 13, so that the moment in the direction of the arrow shown in the figure acts and the table 3 tilts to the right.
[0047]
Here, in this embodiment, the weight sensor 30 is provided below the table 3, and the substrate 32 provided with the fixed electrode 34 of the weight sensor 30 is provided with a hole 32 </ b> P, and the movable electrode of the table 3 and the weight sensor 30 is provided. Since the sensor spring 31 serving as the portion 33 is rigidly connected to the support member 17 through the hole 32P of the substrate 32, a moment force acts on the support member 17 due to the inclination of the table 3 to move the movable electrode 33 of the sensor spring 31. Will be inclined.
[0048]
That is, the gap between the fixed electrode 34a on the left side in the figure and the movable electrode 33 (part A in the figure) and the gap between the fixed electrode 34b on the right side and the movable electrode 33 (part B in the figure) cause a difference between the electrodes. By comparing the capacitance signals, the placement position information of the food 4 on the table 3 can be detected.
[0049]
The sensor spring 31 shown in FIG. 7 is made of a flat spring steel material, and has a torsion spring structure in which the movable electrode portion 33 at the center is supported by two L-shaped or U-shaped beams 31a and 31b. . The sensor spring 31 is fixed to the outside by screws (not shown) at the outer ends of the two beams 31a and 31b. In the structure of the sensor spring 31 according to the present embodiment, the rigidity due to bending deformation is smaller in the long side direction than in the short side direction of the beams 31a and 31b, so that the structure is easily inclined in the arrow direction shown in the drawing.
[0050]
That is, when the position of the food 4 on the table 3 is to be detected in the direction of the arrow as the position of the food 4, the sensor spring 31 as shown in the figure may be used. FIG. 8 shows an embodiment of the structure of the fixed electrode 34 in this case.
[0051]
FIG. 8 shows the substrate 32 of the capacitance-type weight sensor 30 having the divided fixed electrodes 34. The present invention relates to the structure of the fixed electrode 34, in which only the pattern of the fixed electrode 34 is shown, and circuit components and the like are not shown. The fixed electrode 34 is divided into two parts 34a and 34b in the direction in which the sensor spring 31 is easily inclined. When the movable electrode 33 is inclined, the capacitance is changed due to a change in the gap between the fixed electrode 34a and the movable electrode 33 in the figure. By comparing the signal and the capacitance signal due to the change in the gap between the lower fixed electrode 34b and the movable electrode 33, the inclination direction of the sensor spring 31 (the direction of the arrow shown in the figure) can be detected.
[0052]
That is, the placement position of the food 4 on the table 3 can be detected. In addition, the total weight of the food 4 can be simultaneously detected by summing the output signals of the capacitance between the two divided electrodes.
[0053]
In the embodiments described above, the fixed electrode unit 34 is divided into four parts (for example, FIG. 5) and two parts (for example, FIG. 8). However, it is needless to say that the number of divisions depends on the placement position and direction of the food 4 to be detected. Alternatively, the division shape may be determined.
[0054]
FIGS. 9 and 10 show a structure of a sensor spring 31 used in a weight sensor 30 capable of detecting weight and position according to another embodiment.
[0055]
FIG. 9 shows the structure of a sensor spring 31 obtained by stamping and molding a single flat plate. The movable electrode 33 is supported by the four beams 33b, and the outer periphery of each beam 33b has an integral structure. Further, in the embodiment, the outer peripheral portion is fixed to the substrate 32 provided with the fixed electrode 34 by a screw (not shown) or the like. By providing a bent portion 35 near the center of the beams 33b2 and 33b4 as shown in the AA cross section in the drawing, the support member 17 (not shown) is attached to the movable electrode portion 33 similarly to the sensor spring 31 shown in FIG. When a moment acts on the movable electrode 33, the movable electrode 33 moves while having an inclination. When the outer peripheral portion is provided and the area of the movable electrode is considered, it is difficult to increase the length of the beam 33b, and the rigidity of the spring becomes very large. If the spring stiffness is large, the output sensitivity of the weight sensor 30 is reduced, so it is necessary to make the spring stiffness appropriate.
[0056]
Therefore, the sensor spring 31 shown in the embodiment is provided with a cutout 33k at the joint between the movable electrode 33 and the beam 33b, and the length of the beam 33b is increased to ensure the appropriate spring stiffness. . In addition, since the outer peripheral portion has an integral structure, workability in assembling, damage of components, prevention of deformation, and the like can be prevented, and reliability is improved.
[0057]
FIG. 10 shows the structure of a sensor spring 31 using a torsion spring formed by stamping and molding a single flat plate. The movable electrode 33 is supported by four L-shaped beams 33c, and the outer periphery of the beam 33c has an integral structure. Further, in the embodiment, the outer peripheral portion is fixed to the substrate 32 provided with the fixed electrode 34 by a screw (not shown) or the like. When the sensor spring 31 according to this embodiment is pressed by the movable electrode 33, the movable electrode 33 moves due to the torsional deformation of the L-shaped portion of the beam 33c. When such an L-shaped beam 33c is used, since the length of the beam 33c has a degree of freedom, the spring rigidity of the sensor spring 31 can be easily designed. When pressure is applied to a substantially central portion of the movable electrode 33, the movable electrode 33 moves substantially in parallel, and the support member 17 from the table 3 is fixed to the movable electrode 33 as shown in FIG. In this case, when a moment due to the placement position of the food 4 on the table 3 acts on the support member 17, the movable electrode 33 can move with an inclination corresponding to the moment. Further, as in the case of FIG. 9, the outer peripheral portion has an integral structure, so that workability in assembling, damage of components, prevention of deformation, and the like can be prevented, and reliability is improved.
[0058]
In the sensor spring 31 shown in FIGS. 9 and 10 as well, as described with reference to FIGS. 4 to 8, the table 3 is formed by using the movable electrode 33 and the split fixed electrode 34 having the same outer shape and size. The weight sensor 30 for detecting the placement position information of the food 4 above can be configured.
[0059]
FIG. 11 is a sectional view showing a structure of a turntable type microwave oven in which a mounting table of the food 4 provided with the weight sensor 30 according to the present embodiment rotates. The rotating food placing table 3t (hereinafter, referred to as a table) on which the food 4 is placed is fixed to the support member 17, and is placed on a table placing member 40 that rotates together with the support member 17 to perform a rotating operation. The other end of the support member 17 is configured to apply a pressure corresponding to the weight of the food 4 to a weight sensor 30 installed in the heating chamber housing 12 below the table 3t.
[0060]
The weight sensor 30 includes, for example, a substrate 32 provided with a divided fixed electrode 34 and a sensor spring 31 provided with a movable electrode 33 as shown in FIGS. The support member 17 includes a second gear 42 at an intermediate portion. Further, a rotation driving means 43 (hereinafter, referred to as a T motor) is fixed to the heating chamber housing portion 12, and a first gear 41 is provided on a rotation shaft of the T motor 43.
[0061]
In this structure, the support member 17 is rotated by transmitting the torque of the T motor 43 from the first gear 41 to the second gear 42. In this embodiment, since the weight sensor 30 is fixed and the support member 17 rotates, the contact portion between the support member 17 and the sensor spring 31 has a sliding structure. Needless to say, it is necessary to use a sliding member or the like in consideration of wear resistance for the sliding surface. In addition, by making the contact portion a surface contact, the movable electrode portion 33 can be inclined by the inclination of the support member 17.
[0062]
In the method of detecting the position of the food 4 placed on the table 3t according to the present embodiment, the gap between the movable electrode 33 and the fixed electrode 34 of the weight sensor 30 changes according to the rotation because the support member 17 rotates. Since the gap between the movable electrode 33 and the fixed electrode 34 becomes narrower in the direction (position) in which the food 4 is mounted, it is possible to detect the mounting position of the food 4 by comparing signals at the divided electrodes. It becomes possible.
[0063]
By adopting such a capacitance type weight sensor 30 having the structure described in the embodiment, the weight of the food 4 placed on the tables 3 and 3t of the microwave oven 1 and the weight of the food 4 on the tables 3 and 3t are reduced. The position can be detected, and the output of the magnetron 5, the rotation of the rotary antenna 7, the aiming of the infrared temperature sensor 21, and the like can be controlled by using the information of the food 4. Therefore, optimal heating control of the food 4 in the microwave oven 1 can be achieved, and the high-quality microwave oven 1 can be provided.
[0064]
【The invention's effect】
As described above, the capacitance-type weight sensor provided with the divided fixed electrodes according to the present invention can detect a change in the gap between each of the divided fixed electrodes and the movable electrode as a capacitance signal. By processing the signal, the tilt direction of the movable electrode can be detected. For this reason, by connecting the table and the movable electrode with a rigid body, it is possible to detect the position information of the food mounted on the table.
[0065]
Further, by each signal processing, food weight information can be simultaneously detected. Thus, the above-described food weight and position information can be detected by one sensor.
[0066]
Also, by using such information, it becomes possible to control the output of the magnetron, aim at the temperature of the food to be heated, and centrally heat the electromagnetic wave from the magnetron to the food position by controlling the rotating antenna. This can shorten the heating time and save energy.
[0067]
Further, since the infrared sensor for measuring the temperature of the food being heated based on the positional information of the food can perform the target temperature measurement of the food, responsiveness and accuracy of the food temperature measurement are improved. By improving these functions, it is possible to provide a more convenient and high-quality cooking device.
[Brief description of the drawings]
FIG. 1 is a diagram showing a main structure of a turntableless microwave oven according to an embodiment of the present invention and a system configuration diagram of detection and control.
FIG. 2 is a cross-sectional view illustrating a detection structure of a weight sensor according to an embodiment of the present invention and a peripheral structure thereof.
FIG. 3 is a sectional view of a weight sensor unit according to an embodiment of the present invention.
4A is a structural view of a sensor spring provided with a movable electrode used in the weight sensor of the present invention, and FIG. 4B is a cross-sectional view taken along line AA of FIG.
FIG. 5 is a structural view of a divided fixed electrode provided on a substrate used in the weight sensor of the present invention.
FIG. 6 is a diagram showing the principle of position information detection by the weight sensor of the present invention.
FIG. 7 is a structural view of a sensor spring according to another embodiment provided with a movable electrode used for the weight sensor of the present invention.
FIG. 8 is a structural view of a divided fixed electrode according to another embodiment provided on a substrate used for the weight sensor of the present invention.
FIG. 9A is a structural view of a sensor spring as another embodiment provided with a movable electrode used in the weight sensor of the present invention, and FIG. 9B is a cross-sectional view taken along line AA of FIG.
FIG. 10 is a structural view of a sensor spring as another embodiment provided with a movable electrode used for the weight sensor of the present invention.
FIG. 11 is a cross-sectional view illustrating a weight sensor of a microwave oven provided with a rotating food placing table according to an embodiment of the present invention and a peripheral structure thereof.
[Explanation of symbols]
2 ... heating room
3 ... Food table (table)
3t ・ ・ Rotating food table (table)
4 ... Food
5 ... magnetron
6 ... Waveguide
7 Rotating antenna
9 ... Rotary antenna motor
17 ... Support member
30 ... weight sensor
33 ・ ・ ・ Movable electrode
34 ... fixed electrode

Claims (3)

In a capacitive weight sensor comprising a movable electrode (33) and a fixed electrode (34) opposed thereto, the fixed electrode (34) is divided into a plurality of movable electrodes (33), and each movable electrode (33) is divided into a plurality of movable electrodes. An electrostatic capacitance type weight sensor characterized in that an electrostatic capacitance signal between (33) and a fixed electrode (34) is obtained. A heating chamber (2) for storing the food (4), a magnetron (5) for heating the food (4), a waveguide (6) for guiding electromagnetic waves, and a rotating antenna (7) for stirring the electromagnetic waves; 2. A heating cooker comprising a rotary antenna motor (9) for driving a rotary antenna (7) and a food mounting table (3) for mounting a food (4), wherein the weight sensor (30) according to claim 1 is used for a food. Each fixed electrode (34) is provided below the mounting table (3), and is divided into a plurality of fixed electrodes (34) in which the food mounting table (3) and the movable electrode (33) of the weight sensor (30) are connected by a support member (17). A function of detecting weight information and position information of the food (4) of the food mounting table (3) by using respective capacitance signals between the movable electrode (33) and the heating electrode (33). vessel. In a heating cooker provided with a heating chamber (2) for storing the food (4), a magnetron (5) for heating the food (4), and a rotating food mounting table (3t) for mounting the food (4), The weight sensor (30) according to claim 1 is provided below the rotating food placing table (3t), and the rotating food placing table (3t) and the movable electrode (33) of the weight sensor (30) are supported by the support member (17). The weight information and the position information of the food (4) on the rotating food placing table (3t) are obtained by using the respective capacitance signals between the fixed electrode (34) and the movable electrode (33) divided into a plurality of pieces. A cooking device characterized by having a function of detecting the temperature.

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