JPH0543704Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> This invention relates to a rice cooker, and more specifically, to a rice cooker that can cook rice with an optimum amount of electricity based on the amount of rice to be cooked.

<Conventional technology> Recent rice cookers are equipped with microcomputers to determine the total number of rice stored in the inner pot, that is, the amount of rice to be cooked, and to use the optimum power consumption based on the result of determining the amount of rice to be cooked. There is a device available that allows you to perform the rice cooking operation.

This type of rice cooker has a first temperature detection section that detects the temperature on the side surface of the inner pot, a second temperature detection section that detects the temperature on the bottom surface of the inner pot, and a first temperature detection section that detects the temperature on the bottom surface of the inner pot. Temperature detection signal from the detection unit (temperature rise gradient,
The amount of rice to be cooked is determined based on the amount of rice (or the time it takes for the temperature to rise to a predetermined temperature, etc.), and the rice cooking power is controlled, and whether the rice is cooked is determined based on the temperature detection signal input from the second temperature detection. It only has a temperature detection part that detects the temperature on the bottom surface of the inner pot, and during cooking, the power to the rice cooking heater is cut off and the temperature detection signal from the temperature detection part (temperature decreasing gradient or rising to a predetermined temperature) is detected. The amount of rice to be cooked is determined based on the amount of rice cooked (e.g., the amount of time it takes to finish cooking, etc.), and the subsequent power for cooking the rice is controlled, and when the temperature detection signal from the temperature detection section reaches a predetermined value, it is determined that the rice is cooked. things were being provided.

<Problem to be solved by the invention> In the rice cooker with the above configuration, the temperature at the side of the inner pot is detected, so a temperature rise gradient corresponding to the amount of rice cooked can be obtained, and the amount of rice cooked can be determined accurately. Although it is possible to accurately determine the amount of cooked rice, it requires a temperature detection section to determine the amount of rice cooked and a temperature detection section to determine the doneness of rice, and the configuration is This has the disadvantage that it becomes complicated.

In addition, in the rice cooker with the above configuration, only one temperature detection unit is required, so the configuration can be simplified, but the amount of cooked rice is determined based on the temperature of the bottom surface of the inner pot. Therefore, if the temperature increase gradient is used as it is for determining the amount of rice cooked, it is necessary to once cut off the electricity to the rice cooking heater and obtain the temperature decrease gradient or the time until the temperature rises to a predetermined temperature.

This is because there is not only water but also rice on the bottom of the inner pot, so the amount of rice heated by the rice cooker and the detected temperature are not necessarily proportional to each other due to the presence of rice, making it difficult to clearly determine the amount of rice cooked based on the temperature rise gradient. I have a dislike.

In particular, when the water runs out, there is rice still containing water on the bottom of the inner pot, so if the amount of rice cooked is small, the temperature will rise rapidly, causing scorching, and the amount of rice being cooked may be too large. If this happens, the temperature will rise slowly and it will become sticky.

Furthermore, when the amount of rice to be cooked is large, there is the inconvenience that uneven cooking occurs between the upper and lower parts of the inner pot (the upper part becomes hard and the lower part becomes soft).

<Purpose of the invention> This invention was devised in view of the above-mentioned problems, and uses only one temperature detection unit to reliably determine the amount of rice to be cooked, and also to ensure that the rice is cooked evenly. The purpose of the present invention is to provide a rice cooker that can cook rice and maintain good heat retention.

<Means for solving the problem> In order to achieve the above object, the rice cooker of this invention has a removable partition plate that prevents the passage of rice and allows the passage of water at a predetermined position in the inner pot. The interior of the inner pot is divided into upper and lower parts, the lower chamber is used as a water storage space, and a center sensor is provided to detect the temperature at the center of the lower surface of the inner pot. A rice cooking amount determination means for determining the amount of cooked rice based on the relationship between a detection signal of the water temperature in the water storage space forming the lower chamber and time, and a rice cooking amount determination means for determining the amount of rice cooked based on the relationship between the detection signal of the water temperature in the water storage space forming the lower chamber and the temperature rise when the water in the water storage space runs out by the center sensor. A rice cooking heater is energized by receiving a determination signal from the rice cooking amount determining means and a determination signal from the rice cooking amount determining means and determining whether the rice is cooked by using the detection signal of the center sensor as an input. The present invention is characterized in that it has an energization amount control means for controlling the amount of energization.

<Function> In the rice cooker having the above configuration, the temperature detected by the center sensor is the temperature of water or hot water stored in the water storage space of the lower chamber in the inner pot. In the first half of the rice cooking process, the temperature of the water stored in the lower chamber increases in proportion to the amount of heating by the rice cooking heater. Moreover, the temperature increase gradient of water temperature is inversely proportional to the amount of rice cooked. Therefore, the amount of cooked rice can be accurately determined in the first half of the rice cooking process based on the temperature of the water stored in the water storage space forming the lower chamber.

Thereafter, the amount of electricity applied to the rice cooking heater is controlled by the electricity supply control means according to the determined amount of cooked rice, and it is possible to perform appropriate control of the amount of electricity applied according to the amount of rice cooked.

After that, when the water is absorbed by the rice and there is no longer any water in the water storage space, the temperature detected by the center sensor will rise rapidly, making it possible to detect that the rice has finished cooking. The heat from the bottom is not transferred directly to the rice, so there is no chance of burning.

<Examples> Hereinafter, examples will be described in detail with reference to the accompanying drawings showing examples.

FIG. 3 is a longitudinal cross-sectional view showing a rice cooker capable of cooking multiple types of rice, such as quick rice, steamed rice, and pilaf, and FIG. 4 is a perspective view of the exterior. Connected so that they can be opened and closed.

To explain in more detail, the above casing 1
is a cylindrical side member 2 whose upper part is made of a thin metal plate, and whose lower part is a bottom member 3 made of synthetic resin. An inner pot storage container 5 is attached inside the casing 1, and an inner pot 6 supported by a rice cooking heater 54 is removably accommodated inside the inner pot storage container 5.

The casing 1 has a bottom member 3 made of synthetic resin attached to the lower end of a side member 2 having a cylindrical shape made of metal, and a shoulder member 11 made of synthetic resin attached to the upper end.

The bottom member 3 is formed into a deep dish shape that can cover substantially the lower half of the inner pot storage container 5. Then, by recessing a predetermined position near the periphery of the bottom upward, power supply parts 34 such as transformers
A power supply component accommodating recess 33 for accommodating the power supply component is formed. Further, a cover 37 is attached to the power supply component recess 33 with screws to prevent the housed power supply component 34 from being exposed to the outside. In addition, 39 is the power supply component housing recess 33.
30 is a cord reel.

The side member 2 is formed by forming a thin metal plate into a cylindrical shape, and the lower end edge and the upper end edge are curved inward to form a substantially cylindrical shape to form ring parts 21 and 22, and the bottom member 3 annular groove 23,
It is made to engage with the annular groove 24 of the shoulder member 11 in a watertight manner, and the engaged state can be ensured by the screw 25. And side member 2
An arc-shaped handle member 26 is rotatably attached to a predetermined position on the upper part of the handle member 26.
A positioning member 27 that allows the handle member 26 to rotate only between a substantially horizontal state and an upright state of less than 90 degrees.
is installed. Therefore, the handle member 26
If it is left in an upright position, it will rotate to a nearly horizontal position due to its own weight.

The shoulder member 11 is made of synthetic resin and has a substantially ring-shaped overall shape, and has a support portion 12 on its upper surface that supports the upper end flange portion 51 of the inner pot storage container 5 in a suspended manner. is forming. and,
A hinge portion 14 that supports the lid unit 7 in a vertically movable manner is formed at a predetermined position, and
The lid unit 7 is positioned directly opposite the hinge portion 14.
It has an engaging part 15 that holds the lid in a closed state.

The inner pot storage container 5 is formed in a shape capable of accommodating the inner pot 6, and has a center sensor 53 for detecting the temperature of the bottom center portion of the inner pot 6 by penetrating the center portion of the bottom surface. At the same time, a rice cooking heater 54 is also attached so as to surround the center sensor 53. The upper end edge portion is curved outward to form an upper end flange portion 51 that can be engaged with the support portion 12 . Note that 55 is a heat shield plate, and a support plate 56 for testing insulation resistance is attached to a predetermined position and brought into contact with the casing of the cord reel 30. 58 is a heat insulating heater attached to a predetermined position on the side surface of the inner pot storage container 5, 59 is a temperature fuse, and 50 is a heat insulating material that surrounds almost the entire side surface of the inner pot storage container 5.

The inner pot 6 has a small diameter portion 9 in a predetermined area near the bottom.
1, and a step portion 92 continuous to the upper edge of the small diameter portion 91 supports a partition plate, such as a slatted plate 93. The slatted board 93 is
A peripheral edge portion 94 supported by the stepped portion 92 is formed in a stepped shape with respect to the remaining portion, and the slatted board 93
The center part of the inner pot 6 is supported in a state close to the bottom surface of the inner pot 6, dividing the inside of the inner pot 6 into upper and lower parts, and a water storage space 95 ( For example, a space in which the distance between the two is set to about 6 mm) is formed. In addition, the above-mentioned slatted board 9
3 may be any space as long as it is placed at a predetermined position in the inner pot 6 and forms a water passage space that prevents rice from passing through and allows water to pass through.For example, the water passage space may be It is sufficient if a plurality of small holes are formed.

The lid unit 7 has an operating lever 78 at a predetermined position on the upper surface directly facing the hinge portion 14, and a heat sink 72 is attached to the lower surface. and,
A lid heater 74 is attached to a predetermined position on the upper surface of the heat sink 72, and a steam packing 73 is attached to the outer periphery of the heat sink 72 so that it can come into contact with the flange portion 61 of the inner pot 6. In addition, the heat sink 7
A one-touch pin 75 is attached to the center of the inner pot 6, and a one-touch packing 77 attached to the center of the lid plate 76 that contacts the stepped portion 62 of the inner pot 6 is detachably attached to the one-touch pin 75. Note that 79 is a lead wire for applying a voltage to the lid heater 74, and 70 is the hole, which is attached at a position intermediate and farthest between the hinge portion 14 and the operating lever 78.

FIG. 1 is a block diagram showing the electrical configuration of the rice cooker, in which a temperature detection signal from a center sensor 53 is supplied to a microcomputer 81 via an A/D converter and an I/O interface (not shown). , a control signal output from the microcomputer 81 is sent to the driver 82 via an I/O interface (not shown) and an A/D converter.
The output signal of the driver 82 is supplied to the rice cooking heater 54.

FIG. 2 is a flowchart explaining the rice cooking operation. After the water absorption process is completed, the rice cooking heater 54 is energized with full power in step, and the temperature detected by the center sensor 53 is set at a predetermined temperature T1 in step. Wait until the microcomputer 8 is reached in step 8.
The timer 1 is started to start a timer, and in step 1, the timer 53 waits until the temperature detected by the center sensor 53 reaches a predetermined temperature T2, which is higher than the temperature T1. After the temperature detected by the center sensor 53 reaches the predetermined temperature T2, the time measurement operation is stopped in step, and the magnitude relationship between the measured time t and the preset reference times t1, t2, t3, and t4 is determined in step. Determine.

As a result of the above determination, if it is determined that t1<t≦t2, the power supplied to the rice cooking heater 54 is set to W1 in step, and if it is determined that t2<t≦t3, the power supplied to the rice cooking heater 54 is set to W1 in step. If it is determined that t3<t≦t4, the power supplied to the rice cooker heater 5 is set to W2.
If it is determined that none of the above is true, that is, t4<t, then in step 12 the power supplied to the rice cooking heater 54 is set to W3.
Set to W4. That is, only water exists in the water storage space 95 in the lower part of the inner pot 6, and the water gradually rises in temperature due to the heat supplied from the rice cooker heater 54 and convects. If the amount is kept constant, the temperature of the water increases, that is, the center sensor 53 at the bottom of the inner pan 6
The temperature rise detected by this will depend on the amount of rice cooked. Therefore, as the amount of cooked rice increases, the temperature rise becomes slower, and by detecting the length of time required for the temperature to rise from the predetermined temperature T1 to the predetermined temperature T2, the amount of cooked rice can be indirectly determined. can be detected.

In this manner, in the first half of the rice cooking process, the amount of cooked rice can be determined based on the relationship between the detection signal of the water temperature in the water storage space 95 outputted from the center sensor 53 and time. This determination is made by the microcomputer 81.

Then, after performing any of the processes from the above-mentioned steps, the rice-cooking process can be performed by continuing to supply the above-mentioned power to the rice-cooking heater 54 in step.

After that, in the step, the center sensor 5
Predetermined temperature T3 where the temperature detected by 3 is higher than 100℃
The rice cooking process is terminated by waiting until the rice cooking heater 54 reaches this point, and the rice cooking process is terminated by cutting off the electricity to the rice cooking heater 54 in a step, and then a shading process is performed in a step.

In summary, the water in the water storage space 95 is not affected by the presence of rice and convects in a heated state, so that the rice present on the partition plate 93 is heated uniformly. In this case, the amount of rice to be cooked is determined only by the center sensor 53, and the rice cooking process is performed using the optimum rice cooking power according to the amount of rice to be cooked, so that the rice can be cooked thickly. Moreover, the amount of rice to be cooked can be determined during the first half of the rice cooking process while performing normal rice cooking control, and a special time for determining the amount of rice to be cooked (for example, without cutting off the power to the rice cooking heater as in the conventional example). Since no special time is required for determining the amount of rice to be cooked, the overall time required for cooking rice can be shortened.

After that, if the water is absorbed by the rice and no longer exists in the water storage space 95, the center sensor 53
Since the detected temperature rapidly rises, it is possible to detect the completion of cooking.Moreover, in this case, the heat at the bottom of the inner pot 6 is not directly transferred to the rice, so no burning occurs.

Furthermore, after the cooking process is completed as described above, heating with steam is performed as if the water had been drained, so that heating is uniform and gelatinization can be promoted evenly.

Also in this case, scorching does not occur.

Also, after the cooking and steaming processes are finished, the temperature of the rice drops and condensation occurs.
Since the condensation flows down into the water storage space 95 through the drainboard board 93, the rice is reliably prevented from becoming sticky, and the humidity inside the inner pot 6 can be adjusted by the flowing water, resulting in good heat retention performance. can be demonstrated.

FIG. 5 is a diagram showing a state in which the drainboard board 93 is supported in the opposite direction, and in this state, the space 9
5 is large and can accommodate a large amount of water, so it can be used as a steamer by energizing the rice cooker heater 54 while placing steamed egg custard or the like on the slatted board 93.

FIG. 6 is a schematic diagram showing another embodiment, in which the small diameter portion 91 and the stepped portion 92 are omitted, and the inner pot 6 is
An upward protrusion 96 is formed at a predetermined position on the bottom surface of the drainboard to support the slatted board 93, and the height of the peripheral edge 94 of the slatted board 93 is higher than the above-mentioned protrusion 96.

Therefore, the rice cooking operation can be performed in the supported state by the protrusion 96, and
When supported by the peripheral edge 94, it can be used as a steamer.

FIG. 7 is a schematic view showing still another embodiment, in which leg portions 97 are formed on the peripheral edge of the slatted board 93, and the leg portions 97 are formed on a portion slightly closer to the inner circumference.
The only difference is that the protrusion 98 is formed in the opposite direction.

Therefore, in this embodiment, the protrusion 98
When supported by the legs 97, the rice cooking operation can be performed, and when supported by the legs 97, it can be used as a steamer.

FIG. 8 is a schematic view showing still another embodiment, in which a partial engagement protrusion 90 is provided above the step portion 92.
At the same time, a notch 99 that can be engaged with the engaging protrusion 90 is engaged with the peripheral edge of the slatted board 93.

Therefore, in the case of this embodiment, by engaging the engaging protrusion 90 and the notch 99, the rice cooking operation can be performed while the grating board 93 is supported on the stepped portion 92. At the same time, it can be used as a steamer when supported by the engaging protrusion 90.

<Effects of the invention> As described above, this invention divides the inside of the inner pot into upper and lower parts, and uses the lower chamber as a water storage space.In the first half of the rice cooking process, the water storage space in the lower chamber is divided by the center sensor. Since the amount of cooked rice is determined based on the water temperature, the amount of cooked rice can be accurately determined using only one sensor, the center sensor. Moreover, it is also possible to determine whether the rice is cooked through the center sensor.

In particular, when water is absorbed by the rice and there is no longer any water in the water storage space, the temperature detected by the center sensor will rise rapidly, making it possible to detect when the rice is cooked. Heat is not transferred directly to the rice, so no burning occurs.

Furthermore, after the cooking process is completed, heating with steam is performed as if the water had been drained, so that heating is uniform and gelatinization can be promoted evenly.

Also, after the cooking and shading process is finished, the temperature of the rice drops and condensation occurs.
Since dew condensation flows down into the water storage space through the partition plate, it is possible to reliably prevent rice from becoming sticky and to exhibit good heat retention performance.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the rice cooker of this invention, Fig. 2 is a flowchart explaining the rice cooking operation, Fig. 3 is a vertical sectional view of the rice cooker, Fig. 4 is an external perspective view, and Fig. 5 to 8 are schematic diagrams showing other embodiments, respectively. 6... Inner pot, 53... Center sensor, 54...
Rice cooking heater, 81...Microcomputer, 9
3... Slatted board.

Claims (1)

[Scope of utility model registration request] A partition plate that prevents the passage of rice and allows the passage of water is removably arranged at a predetermined position in the inner pot to divide the inside of the inner pot into upper and lower parts, and the lower chamber is used as a water storage space.
Furthermore, a center sensor detects the temperature at the center of the lower surface of the inner pot, and the amount of rice cooked is determined based on the relationship between the detection signal of the water temperature in the water storage space forming the lower chamber and the time, which is output from the center sensor in the first half of the rice cooking process. a rice cooking amount determining means for determining the amount of cooked rice; and a rice completion determining means for detecting a temperature rise when the water in the water storage space runs out by the center sensor and determining whether the rice is cooked by inputting a detection signal from the center sensor. A rice cooker comprising: an energization control means for controlling the amount of electricity supplied to the rice-cooking heater by inputting a determination signal from the rice cooking amount determination means and a determination signal from the rice cooking completion determination means.