JPH0449911A - Heating cooker - Google Patents

Abstract

PURPOSE:To obtain a cooker which always detects accurate temperature and is easily manufactured by a method wherein an infrared ray sensor is arranged outside an inner pot, which detects infrared rays radiated from the inner pot to measure the temperature of the inner pot. CONSTITUTION:An infrared ray sensor 3 is located immediately below a main body 20 of a shield drum 2 with an infrared ray intake window 30 facing an inner pot U, and detects infrared rays radiated from the inner pot U through the main body 20 to measure the temperature of the inner pot U according to the strength of the infrared rays. Power supply to a heater H and an ancillary heater (h) is controlled corresponding to the outputs from the infrared ray sensor 3 to perform temperature control for rice cooking. Thereby, as the temperature of the inner pot U can directly be detected by the infrared ray sensor 3, the accurate temperature of the inner pot U can always be measured, and also temperature control can be sensitively performed in response to delicate changes in the temperature of the inner pot U.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an electric rice cooker, an electric rice cooker, and a heat cooker, and more specifically, the present invention relates to an electric rice cooker, an electric rice cooker, and a heat cooker. The present invention relates to a cooking device equipped with a detection device.

<Prior Art> Conventionally, for example, an electric rice cooker serving as the heating cooker has used a temperature detection device having a structure shown in FIG.

The temperature detection device shown in the figure includes a sensor case 90 placed in the center of a ring-shaped heater H on which an inner pot U is placed and heated, and a temperature sensor 91 placed inside this sensor case 90. and an inner pot detection switch 92.

The sensor case 90 is arranged so as to be movable up and down relative to the heater H, and is pressed by a coil spring 93 so as to protrude upward from the top surface of the heater H.

The temperature sensor 91 is of a type such as a thermistor that performs measurement by contacting the object to be measured, and is supported by a support member 95 disposed inside the sensor case 90 while being inserted into the protective tube 94. The sensor case 90 is disposed in contact with the lower surface of the lid 90a, which contacts the inner pot U, in the upper part of the sensor case 90.

The inner pot detection switch 92 includes a reed switch 92a and a magnet 92b, which are arranged to face each other across a groove 95a formed below the support member 95, and a magnetic shield that is inserted into and removed from the magnet 95a as the sensor case 90 moves forward and backward. Board 92
It is equipped with c.

According to the temperature detection device made up of the above-mentioned parts, when the inner pot U is placed on the heater H, the sensor case 90 is pushed back downward against the pressing force of the coil spring 93. Then, a magnetic shielding plate 92c is inserted into the groove 95a to shield the magnetism of the magnet 92b acting on the reed switch 92a, and the contact of the reed switch 92g is opened, allowing the temperature sensor 91 to measure the temperature of the inner pot U. will be started. Also, Ko.

The lid 9 of the sensor case 90 is
0a is brought into contact with the bottom surface of the inner pot U, and the heat of the inner pot U is transmitted to the temperature sensor 91 placed directly under the lid 90g,
Temperature control for cooking rice is performed according to the output value of temperature sensor 91.

When the inner pot U is removed from above the heater H, the sensor case 90 protrudes from the top surface of the heater H due to the pressing force of the coil spring 93, and the magnetic shielding plate 92c of the inner pot detection switch 92 moves into the groove. 95a.

Then, the magnetism of the magnet 92b acts on the leet switch 92a, the contact of the leet switch 92g is closed, and the measurement of the temperature of the inner pot U by the temperature sensor 91 is stopped. Further, when the contact of the reed switch 92a is closed, the supply of power to the heater H is cut off, thereby preventing cooking.

<Problems to be Solved by the Invention> In the conventional temperature detection device, as described above, the temperature sensor 91 is protected by the protective tube 94, and
Since it is in contact with the lid 90a of the sensor case 90, the heat of the inner pot U is conducted to the temperature sensor 91 via the lid 90a and the protective tube 94. For this reason, there was a problem in that the accurate temperature of the inner pot U could not be measured, and a time lag occurred in the temperature measurement, making it impossible to properly control the temperature.

In addition, foreign objects may become trapped between the lid 90a and the inner pot U.
There are cases where the two do not come into contact with each other properly, and in this case as well, there is a problem that accurate temperature detection cannot be performed.

In addition, in the temperature detection device having the above configuration, the sensor case 90 can be smoothly moved forward and backward, and the temperature sensor 91 can be moved forward and backward smoothly.
In order to abut the inner pot U at the correct position, precise dimension matching is required for the parts that slide into contact with each other, such as the groove 95a of the support member 95 and the magnetic shielding plate 92c of the inner pot detection switch 92. There was also the problem that it was time consuming.

The present invention has been made in view of the above circumstances, and
It is an object of the present invention to provide a heating cooker that can always detect accurate temperature and is easy to manufacture.

Means for Solving the Problems> In order to solve the above problems, the heating cooker of the present invention is a heating cooker in which an inner pot is detachably housed in an outer case that configures the outer shape of the heating cooker. The present invention is characterized in that an infrared sensor is disposed outside the inner pot to measure the temperature of the inner pot by detecting infrared rays emitted from the inner pot.

Moreover, the cooking device of the present invention can also be equipped with an optical fiber that guides infrared rays emitted from the inner pot to an infrared sensor.

Function> In the heating cooker of the present invention having the above configuration, the temperature of the inner pot can be measured without contact by receiving infrared rays emitted from the inner pot using an infrared sensor.

Furthermore, when an optical fiber is provided that guides infrared rays emitted from the inner pot to an infrared sensor, the infrared sensor can be placed at any position that is less affected by heat.

<Example> The heating cooker of the present invention will be described below with reference to the drawings showing an electric rice cooker as an example.

FIG. 1 is a partially cutaway side view of the electric rice cooker of this embodiment, with an inner pot U removably housed in an outer case C1 that forms the outer shape of the rice cooker, with a heat insulating material I interposed therebetween. A case C2 is provided.

A ring-shaped heater H in which a nichrome wire H2 is embedded is arranged on the bottom surface of the inner case C2 to place and heat the inner pot U, and an auxiliary heater h is arranged on the outer periphery of the side wall of the inner case C2. is located.

Further, a temperature detection device A is arranged in the central through hole H1 of the heater H to detect the temperature of the inner pot and control the temperature for cooking rice.

As shown in the figure and FIG. 2 (Al), the temperature detection device A includes a shielding cylinder 2 supported in the through hole H1 by a support fitting 1 so as to be able to move forward and backward in the vertical direction, and this shielding cylinder. It includes an infrared sensor 3 and a limit switch 4 arranged below the body 2.

The support fitting 1 includes a disc-shaped main body 10 fixed to the lower surface of the heater H so as to close a through hole H1, and an annular support recess with a substantially U-shaped cross section formed in the center of the main body 10. 11.

The shielding cylinder 2 includes a cylindrical main body 20 and a flange portion 21 formed at the lower end of the main body 20. Also,
The shield cylinder 2 has an arm 22 on the flange portion 2 for pressing the push button 41 of the limit switch 4 when the inner pot U is placed on the heater H and the shield cylinder 2 is lowered.
It extends downward from one point on the outer periphery of 1.

The shielding cylinder 2 is constructed by inserting the flange portion 21 into the support recess 11 of the support fitting 1 and interposing the coil spring 5 between the flange portion 21 and the lower surface 11a of the support recess 11. It is supported within the central through hole H1 of the heater H so as to be able to move forward and backward in the vertical direction, and is always pressed upward by the coil spring 5.

The infrared sensor 3 is disposed directly under the main body 20 of the shielding cylinder 2 with a window 30 for capturing infrared rays facing the inner pot U. By detecting the strength of the inner pot U
Measure the temperature of.

In addition, the code|symbol 31 in the figure has shown the lead wire of the infrared sensor 3.

As the infrared sensor 3, a thermistor bolometer,
Pyroelectric elements (TGS, PbnOs, etc.), infrared detection elements (PbS, lmSb, Cd-Hg
Various conventionally known infrared temperature sensors such as -T, etc.) can be used.

As the infrared rays measured by the infrared sensor 3, infrared rays of all wavelengths from the near infrared region to the far infrared region can be used.

As described above, the limit switch 4 is used to detect the up and down of the shielding cylinder 2 based on whether or not the push button 41 is pressed by the arm 22, and based on this, to detect the presence or absence of the inner pot U on the heater H. Ru.

The infrared sensor 3 and limit switch 4, together with the heater H, are mounted on a metal fitting (not shown) fixed to the main body of the cooking device.

According to the heating cooker of this embodiment, which is equipped with the temperature detection device A consisting of the above-mentioned parts, when the inner pot U is placed on the heater H, the shielding cylinder 2 is exposed to the pressing force of the coil spring 5. is pushed back downwards against the Then, the push button 41 of the limit switch 4 is pressed by the arm 22, the contact point of the limit switch 4 is closed, and the inner pot U is detected by the infrared sensor 3.
temperature measurement begins. Then, the power supplied to the heater H and the auxiliary heater h is adjusted according to the output value of the infrared sensor 3, and temperature control for rice cooking is performed. Further, the tip of the shielding cylinder 2 is brought into contact with the bottom surface of the inner pot U by the pressing force of the coil spring 5, and the infrared rays emitted from the heater H are prevented from being input to the infrared sensor 3 as noise. .

On the other hand, when the inner pot U is removed from above the heater H, the shielding cylinder 2 protrudes from the upper surface of the heater H due to the pressing force of the coil spring 5, and accordingly, the arm 22 pushes the push button 41 of the limit switch 4. is released, the contact of the limit switch 4 is opened, and the measurement of the temperature of the inner pot U by the infrared sensor 3 is completed. Furthermore, when the contact point of the limit switch 4 is open, the supply of power to the heater H and the auxiliary heater h is cut off, thereby preventing cooking.

In the electric rice cooker of the above embodiment, the temperature of the inner pot U can be directly measured by the infrared sensor 3. Therefore, the temperature of the inner pot U can always be accurately measured, and the temperature of the inner pot U can be sensitively reacted to.

The temperature detection device A of the heavy ring rice cooker also includes a shielding cylinder 2 for shielding infrared rays emitted from the heater H.
Since this is provided, the influence from the ring-shaped heater H can be eliminated even though the heater H is disposed close to the ring-shaped heater H.

Furthermore, in the above embodiment, the infrared sensor 3 is mounted on a metal fitting fixed to the main body of the heating cooker, and the shielding cylinder 1 as a movable part does not require precise dimension adjustment. The manufacturing process can be simpler than before.

Next, a modification of the temperature detection device A shown in FIG. 3 will be described.

In the temperature detection device A shown in the same figure, the infrared sensor 3 is arranged not directly below the main body 20 of the shielding cylinder 2, but in a position isolated from the shielding cylinder 2, and the infrared sensor 3 is arranged at a position isolated from the shielding cylinder 2, and the infrared sensor 3 is arranged at a position isolated from the shielding cylinder 2. This temperature detection device A differs from the temperature detection device A in the previous embodiment in that an optical fiber 6 is provided for guiding the temperature to the infrared sensor 3.

The other parts are constructed in the same way as the previous one.

That is, the shielding cylinder 2 is supported by the support fitting 1 fixed to the lower surface of the heater H, and is disposed within the central through hole H1 of the heater H so as to be able to move forward and backward in the vertical direction. It is constantly pressed upward by the coil spring 5.

Further, below the shielding cylinder 2, there is a limit switch that detects the upper and lower sides of the shielding cylinder 2 based on whether or not the push button 41 is pressed by the arm 22, and detects the presence or absence of the inner pot U on the heater H based on the detection. 4 is attached on top of a metal fitting fixed to the main body of the heating cooker.

On the other hand, the infrared sensor 3 is mounted on a circuit board 7 located at a remote location so as not to be affected by the heat from the heater H.

Optical fiber 6 for guiding infrared rays to the infrared sensor 3
is fixed in the vicinity of each end surface by the support metal fitting 1 and the holder 8, with one end surface facing the inner pot U and the other end surface facing the window 30 of the infrared sensor 3.

In the temperature detection device A having the above configuration, the infrared sensor 3
is mounted on the circuit board 7 located at a remote location that is not affected by the heat from the heater H, so it is possible to reliably prevent the infrared sensor 3 from malfunctioning or being damaged due to heat. Further, since lead wires that tend to pick up noise can be omitted, it is possible to prevent the infrared sensor 3 from malfunctioning due to noise.

Furthermore, the temperature detection device mentioned above! In A, since it is not necessary to align the shielding cylinder 1 and the infrared sensor 3, the manufacturing process can be further simplified.

Next, a modification of the temperature detection device A shown in FIG. 4 will be described.

In the temperature detection device A shown in the figure, the infrared sensor 3 is
It also has the function of detecting the presence or absence of the inner pot U on the heater H, and is different from the previous two in that a limit switch and the like are omitted.

That is, the infrared sensor 3 starts detecting infrared rays at the same time as the power of the cooking device is turned on, and is used to detect the presence or absence of the inner pot U on the heater H based on the difference in the amount of incident infrared rays.

On the other hand, during cooking, the infrared sensor 3
Similarly to the above example, it is used to measure the temperature of the inner pot U from the amount of infrared rays emitted from the inner pot U.

The other parts are configured similarly to the previous two examples.

That is, the shielding cylindrical body 2 is supported by the support fitting 1 fixed to the lower surface of the heater H, and is disposed within the central through hole H1 of the heater H so as to be able to move forward and backward in the vertical direction. It is constantly pressed upward by the coil spring 5.

As described above, in this temperature detection device A, the infrared sensor 3 also has the function of detecting the presence or absence of the inner pot U.
Since limit switches and the like can be omitted, the number of parts can be reduced. Further, since there is no interlocking mechanism between the shielding cylinder 2 and the limit switch, the manufacturing process can be further simplified.

The temperature detection device A of each of the above-mentioned modifications was arranged to measure the temperature of the bottom surface of the inner pot U, but the temperature detection device A in the cooking device of the present invention is located on the side of the inner pot U. It may be arranged to detect the temperature of the wall surface. In that case, the influence of the heat from the heater H is small, so the shielding cylinder 1 can be omitted.

The shielding cylindrical body 1 may not move up and down, but may be fixed at a position where the tip thereof contacts the bottom surface of the inner pot U when the inner pot U is placed on the heater H.

In the modification shown in FIG. 4, the infrared sensor 3 is placed facing the bottom of the inner pot U, but similarly to the one shown in FIG. 3, the infrared sensor 3 is placed at a remote position and The infrared rays may be guided to the infrared sensor 3 by.

The configuration of the present invention can be applied to cooking devices other than the electric rice cooker described in the embodiments, such as an electric pot and an electric rice cooker without a heat retention function.

In addition, various design changes can be made without changing the gist of the present invention.

<Effects of the Invention> The heating cooker of the present invention is configured as described above,
Since the temperature of the inner pot can be measured without contact using an infrared sensor, accurate temperature can be detected without any time lag, and temperature control can be optimized. Furthermore, since there are no moving parts that require delicate dimensional adjustment, manufacturing is facilitated.

Furthermore, when equipped with an optical fiber that guides the infrared rays emitted from the inner pot to the infrared sensor, the infrared sensor can be placed in any position that is less affected by heat. It is possible to reliably prevent damage.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway side view showing an electric rice cooker as an embodiment of the cooking device of the present invention, and FIG. 3 is a sectional view showing a modified example of the temperature sensing device, FIG. 4 is a sectional view showing another modified example of the temperature sensing device, and FIG. It is a sectional view showing an example of the temperature detection device in a container. C1... Outer case, U... Inner pot, 3... Infrared sensor, 6... Optical fiber.

Claims (1)

[Scope of Claims] 1. In a heating cooker in which an inner pot is detachably housed in an outer case that forms the outer shape of the cooking device, infrared rays emitted from the inner pot are directed outward of the inner pot. A heating cooker characterized by being equipped with an infrared sensor that detects and measures the temperature of an inner pot. 2. The heating cooker according to claim 1, further comprising an optical fiber that guides infrared rays emitted from the inner pot to an infrared sensor.