JPH04109914A - Rice boiler - Google Patents

Abstract

PURPOSE:To judge the amount of boiled rice with good accuracy only by one sensor by measuring the time required for raising the temperature, measuring the number of times of turning on and off a heating means during the pre- boiling time, and deciding the ratio of current application to the heating means from the measured results to be output to a rice boiling control means. CONSTITUTION:There are provided a timing means 6 for measuring the time required for raising the temperature, and an ON-OFF frequency detecting means 7 for measuring the number (of times for turning on and off a heating means by a heating control means 3 during the pre-boiling time. The ratio of current application to the heating means is decided from the measured time (t) and the ON-OFF frequency alpha to decide the current application ratio out putting to a rice boiling control means 5. In the pre-boiling process, it is important to keep the temperature of a pot 1 having rice to be boiled there is at a constant temperature during a designated time. In the case where the quantity of rice to be boiled is small, it is possible to execute the ON-OFF operation of a heating heater 2 with a small frequency to keep the rice to be boiled, that is, the temperature of the pot 1 is kept at a constant temperature during a designated time.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a rice cooker for general household use.

Conventional technologyIn recent years, microcomputers (hereinafter referred to as microcomputers)
Rice cookers that are controlled by this method have become mainstream in the market, and they are controlled to produce the ideal rice cooking that has long been said to be possible, such as choro-choro-medaka-pappa.

Especially in the boiling part, it is said to be important to cook the rice with a heat that is commensurate with the amount of rice to be cooked, and for this reason, determining the amount of rice to be cooked is important. In conventional rice cookers, in order to determine the amount of rice cooked, a temperature detection means is installed to detect the temperature of the pot.
A method is used in which the amount of cooked rice is detected based on the rise in temperature of the pot and the heat power during boiling is controlled.

On the other hand, in recent years, the rice cooker market has become polarized into high-end types and popular types, and the popular types have fewer temperature sensors, such as thermistors, which are often used as temperature detection means, due to the overall cost of the product. Sensing is done with just one piece.

Problem to be Solved by the Invention III However, in the conventional rice cooker described above, the temperature is detected by a single sensor installed at the bottom of the WA where temperature information can easily be obtained. There are many variations in temperature measurement due to the influence of heat from the heater.
As a result, there was a problem in that the heat power setting during boiling varied widely.Furthermore, variations in power supply voltage caused differences in temperature rise even for the same amount of cooked rice, making it difficult to accurately determine the amount of cooked rice. The problem was that there was no.

It is an object of the present invention to solve these problems and provide a rice cooker that can accurately determine the amount of cooked rice even with a single sensor.

Means for Solving the Problems In order to achieve the above objects, the present invention provides a pot for storing rice, a heating means for heating the pot, and a device for turning on the heating means.
・A heating control means for OFF control, a temperature detection means for detecting the temperature of the steel, and the output of this temperature detection means is input, and the heating control means is controlled to perform pre-cooking, finished cooking, and uneven cooking in this order. A rice cooking control means for cooking rice and the output of the temperature detection means are input, and from a predetermined first predetermined temperature T1, a second predetermined temperature is predetermined to be higher than this temperature T1. A clock means measures the time required for the temperature to rise to T2, and the heating means is turned on and off by the heating control means during pre-cooking.
, an ON/OFF frequency detection means for measuring the number of ON/OFF operations α, and energization rate determining means for determining the energization ratio to the heating means on the side of the time t and the ON/OFF frequency, and outputting the energization ratio to the rice cooking control means. There is.

In addition, at this time, assuming a power outage in the transformer power supply, a power outage detection means is provided to detect a power outage in the AC power supply, and ON/O
If the AC power supply fails while measuring the FFFF count α,
It is also configured to have a constant value.

Effect With the above configuration, even if temperature is detected by one sensor and there are variations in temperature measurement, the current conduction rate in the cooking process etc. is determined from α and t.
As a result, there is less variation in the heat setting during boiling, making it possible to provide a rice cooker that can accurately determine the amount of cooked rice using just one sensor.

Embodiment Next, a rice cooker according to an embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a block diagram of main parts of a rice cooker according to an embodiment of the present invention. In the figure, 1 is a pot that stores rice and water to be cooked. Reference numeral 2 denotes a heater serving as heating means, which heats the pot 1. Reference numeral 3 denotes a heater control means, which is a heating control means, and controls the heating heater 2 to turn on and off. 4 is a temperature detection means that detects the temperature of the pot 1. Reference numeral 5 denotes a rice cooking control means, which receives the output of the temperature detection means 4 as an input, controls the heater control means 3, and performs the following steps in the order of pre-cooking (water absorption process of rice), rice-cooking process (boiling process), and uneven cooking process). Let them cook the rice. Reference numeral 6 denotes a timer, which receives the output of the temperature detection means 4 as an input, and calculates the time required for the temperature to rise from a first predetermined temperature T1 to a predetermined second predetermined temperature T2 (>Tl). Measure time. Reference numeral 7 denotes an ON/OFF frequency detection means, which measures the number of times α of the heating heater 2 being turned ON/OFF by the heater control means 3 during pre-cooking. 8 is an energization rate determining means, which determines the time t and this ON/OFF.
On the number of times side, the energization ratio to the heating heater 2 after cooking (boiling step) is determined and outputted to the rice cooking control means 5.

Further, 9 is an AC power supply, and 10 is a power outage detection means, which detects a power outage of the AC power supply 9 assuming that the AC power supply 9 has a power outage, and when the AC power supply 9 has a power outage during the measurement of α. Let α be a constant value.

Next, the operation of the rice cooker having the above configuration will be explained using FIGS. 2 and 3.

FIG. 2 is a diagram showing how the heater 2 is turned on and off during the pre-cooking process of the rice cooker according to an embodiment of the present invention.

In the pre-cooking process, it is important to maintain the temperature of the rice cooker 11 containing the cooked rice at a constant temperature for a predetermined period of time.

First, when the amount of rice to be cooked is small, in order to keep the temperature of the rice to be cooked, that is, the pot 1, at a constant temperature for a predetermined period of time, as shown in FIG. 2(a), turn on the heating heater 2. OFF
It can be carried out fewer times.

On the other hand, when the amount of rice to be cooked is large, the heating heater 2 is turned on in order to keep the temperature of the rice to be cooked, that is, the pot 1, at a constant temperature for a predetermined period of time, as shown in FIG. 2(b).・This means that the number of OFF cycles must be increased.

The number of times obtained here is α.

On the other hand, FIG. 3 is a diagram showing the time course of the temperature rise of the pot 1 detected by the temperature detection means 4 of the rice cooker according to an embodiment of the present invention.

First, when the amount of rice to be cooked is small, the temperature of the rice to be cooked, that is, the pot 1, increases as shown by the solid line in FIG. Naturally, in this case, from the predetermined first predetermined temperature T1 to the predetermined second predetermined temperature T2.
The time t required for the temperature to rise to (>TI) is shorter as shown by tl.

Conversely, when the amount of rice to be cooked is large, the temperature of the rice to be cooked, that is, the pot 1, increases as shown by the dotted line in FIG. Naturally, in this case, the first predetermined temperature T
1 to a predetermined second predetermined temperature T2 (
The time t required for the temperature to rise to >TI) is longer as shown by t2.

The time thus obtained is t.

In this embodiment, the amount of rice to be cooked is determined from α and t obtained in this manner, and the energization rate (i.e., heating power) in the boiling process is determined.

If there is a power outage during the pre-cooking process, the heating heater 2 can be turned on and off as shown in Figure 2.
Since the number of times is measured to be smaller than the actual value, a power outage detection means 10 is provided to detect the AC power source 9, and if the AC power source 9 experiences a power outage during the measurement of α, α is set to a constant value. This is to prevent any problems from occurring.

Further, when the power supply voltage is low, the heating output of the heater 2 decreases, so α tends to increase even if the amount of rice cooked is the same. Therefore, if the presence or absence of a drop in the power supply voltage is determined based on this α, and the amount of cooked rice obtained from t is corrected according to α,
It is possible to determine the amount of cooked rice by taking into account fluctuations in power supply voltage.

In addition, in one temperature detection means 4 disposed at the bottom of the pot, a fourth
The detection of the high temperature T2 shown in the figure varies due to the thermal influence of the heating heater 2, but if the amount of cooked rice is determined at a certain level using α, if t deviates due to a large detection deviation of T2. It is also possible to prevent misjudgment of the amount of cooked rice.

Although a heater is used as the heating means in this embodiment, an electromagnetic induction heating coil may also be used, and in the case of this heating coil, heating may be controlled by duty control or the like.

Effects of the Invention As described above, the present invention provides a pot for storing rice,
A heating means for heating this pot and turning this heating means on and off.
a heating control means for FF control; a temperature detection means for detecting the temperature of the pot; the output of the temperature detection means is input;
A rice cooking control means that controls the heater control means to cook rice in the order of pre-cooking (rice water absorption process), finished cooking (boiling process), and uneven cooking process), and the output of the temperature detection means as inputs. , from a predetermined first predetermined temperature TI to a predetermined second predetermined temperature T
2 (>Tl); and an ON/OFF unit that measures the number of times the heating means is turned on and off by the heating control means during pre-cooking.
OFF number detection means, the time t and this ON/OFF
Since it is provided with an energization rate determining means that determines the energization ratio to the heating means from the number of times α and outputs it to the rice cooking control means, the temperature is detected by one sensor, and due to variations in temperature measurement, Even if there is variation in t, which is related to the amount of rice cooked, the energization rate is determined by taking into account the value of α in addition to This means that it is possible to provide a rice cooker that can accurately determine the amount of rice cooked using a sensor.

In addition, at this time, assuming a case where the AC power supply fails, a power failure detection means is provided to detect a power failure of the AC power supply, and if the AC power supply fails during the measurement of α, α is set to a constant value. Because the rice cooker is configured as follows, even if there is a power outage during rice cooking, it is possible to provide a rice cooker with no worries.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of the main parts of a rice cooker according to an embodiment of the present invention,
FIG. 2 is a diagram showing the ON/OFF state of the heating heater 2 during the pre-cooking process of the rice cooker according to an embodiment of the present invention, and FIG. 3 is a diagram showing the temperature detection means 4 of the rice cooker according to the embodiment of the present invention. FIG. 3 is a diagram showing the time course of the detected temperature rise of the pot 1. FIG. 1... Pot, 2... Heater, 3.
... Heater control means, 4 ... Temperature detection means, 5 ... Rice cooking control means, 6 ... Timing means, 7 ... ON. OFF number detection means, 8
... Energization rate determining means, 9 ... AC power supply, 10 ... Power failure detection means. Name of agent: Patent attorney Haruaki Koba and two others Figure 1 Figure 2 front is 11-1 yesterday Figure 3

Claims (2)

[Claims] (1) A pot for storing rice, etc., a heating means for heating the pot, a heating control means for controlling ON/OFF of the heating means, a temperature detecting means for detecting the temperature of the pot, and a temperature detecting means for detecting the temperature of the pot. A rice cooking control means takes the output of the temperature detection means as an input, controls the heating control means and cooks the rice in the order of pre-cooking, finishing, and uneven cooking, and the output of the temperature detection means is input, and a predetermined first From the predetermined temperature T1, the temperature T
a timing means for measuring the time required for the temperature to rise to a second predetermined temperature T2 predetermined to be higher than 1; and the number of times the heating means is turned on and off by the heating control means during pre-cooking. ON/OFF to measure α
a number detection means, the time t and the ON/OFF number α;
and energization rate determining means for determining the energization ratio to the heating means from the above and outputting the determined energization rate to the rice cooking control means. (2) It has a power outage detection means for detecting a power outage of the AC power supply,
2. The rice cooker according to claim 1, wherein if the AC power supply fails during measurement of the ON/OFF frequency α, α is kept at a constant value.