JPH0655180B2 - Insulated rice cooker - Google Patents

Description

TECHNICAL FIELD The present invention relates to a heat retaining rice cooker having a heat retaining function.

(Prior Art) As a first example, a conventional warm rice cooker is shown in FIGS.
As shown in the figure, a heat insulation heater is installed inside the main body and inside the lid.
303, 313 and 101, 111 are provided, and the heater for keeping the lid 10
1 and 111 are continuously energized by the rice cooker / heat retention switching relay 13, and the body heat retaining heaters 303 and 313 are energized while ON-OFF control is performed by the thermal reed switch 14 and the heat retaining relay 12 which operate at a preset temperature. ， Many people try to keep the temperature of cooked rice inside the pot constant.
Also, as a second conventional example, as shown in FIG. 6, the lid and the body are turned on and off by the heat-retaining heaters 15 and 16 which are continuously energized via the heat-retention switching relay 13 and the thermal reed switch 14. Some also have controlled heat retaining heaters 121 and 323.

(Problems to be Solved by the Invention) In the first conventional example, when the temperature of the thermal reed switch 14 and the thermal insulation relay 12 is higher than the operating temperature, the thermal insulation heaters 303 and 313 are not energized at all, and the thermal reed with respect to the temperature change of the cooked rice inside the pot. Due to the problem of followability of the switch 14 and the heat retention relay 12, the temperature inside the kettle cannot be kept constant and has a certain temperature range, which may cause yellowing of cooked rice due to heat retention and impair the flavor. Further, the second conventional example has the warming heaters 15 and 16 which are always energized through the rice cooker / keeping heat switching relay 13, so the above-mentioned drawbacks are improved, but a warming heater twice as large as that of the first conventional example is required. However, there is a drawback in that it cannot be offered to general consumers at low cost because the cost increases.

(Means for Solving Problems) The present invention has been made in order to solve the above-mentioned drawbacks, and a warming heater is provided in each of the lid and the body and a temperature sensor for detecting the temperature of the body is provided. , A microcomputer provided with an energization control element for controlling energization to the heat-retaining heater, which is provided individually or commonly to both the lid and the body, and a determination means, a timer means, and an energization control means for operating the energization control element, By controlling the energization control element via the energization control means by the output of the judging means and the output of the timer means according to the detection result of the sensor, the difference in the heat retention temperature is reduced, and the heat retention type rice cooker that does not require a large number of heat retention heaters is provided. To provide.

(Operation) By doing so, when the output of the judging means is equal to or lower than the preset temperature, the energization control element via the energization controlling means energizes the heat retaining heaters of both the lid and the body, and the output of the judging means is preset. When the temperature exceeds the specified temperature, the energization control element operates via the energization control means in a constant ON-OFF cycle by the output of the timer means, and the heat insulation heaters of both the lid and the body are turned on or off in separate ON-OFF cycles or simultaneously. To be done.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view of a heat retention type rice cooker according to the present invention, and FIGS. 2 and 3 are circuit diagrams related to the energization control of the heat retention heater.

In the figure, 1 is a warming heater consisting of a lid heater, 2
Is a lid, 3 is a heat-retaining heater including a body heater, 4 is a temperature sensor, 5 is a body, 6 is a body, 7 is a control board, and 8 is a microcomputer. The warming heater 1 is attached inside the lid 2, and the warming heater 3 and the temperature sensor 4
Is attached to the body portion 6 of the main body 5. The temperature sensor 4 is a one-point temperature detection type sensor such as a thermal reed switch or a multi-point temperature detection type sensor such as a thermistor, and in any case, the temperature is kept at about 70 ° C and the output changes. ing. A control board 7 is attached inside the main body 5, and the temperature sensor 4 is attached to the control board 7.
Determination means for determining whether the output of above is above or below the above operating temperature
81 and an energization control means 83, which is a base for energizing the heat retention heaters 1 and 3 through the energization control elements 11 and 12, according to the result of the judgment, and a timer means 82 for performing a time counting operation. These means 81, 82 and 83 are respectively provided in the microcomputer 8 and the judgment means 81 has a configuration in which the output of the temperature sensor 4 is input.

Next, the operation of the present invention will be described.

Rice is cooked by the user's operation, and when rice is cooked, it is automatically switched to the heat retention state. Since the cooked rice in the main body 5 is higher than the operating temperature of the temperature sensor 4 immediately after cooking the rice, the output of the temperature sensor 4 is judged to be high temperature by the judgment means 81 of the microcomputer 8 in the control board 7.
As a result, the timer means 82 operates, and the energization control elements 11 and 12 are actuated via the energization control means 81 by the preset count value of the timer means 82, and the warm heaters 1 and 3 are energized for a certain period of time, respectively. Stop energizing for hours
Repeat ON-OFF cycle. By setting the switching time of the ON-OFF cycle to be sufficiently short, it is possible to obtain the effect of reducing the heat generation amount of the heat insulation heaters 1 and 3. That is, as an example, when the 20 W warming heater 3 is energized for 10 seconds with a commercial power supply 17 of 100 V AC, and is energized in an ON-OFF cycle with a 10 second rest, it is the same as when the 10 W warming heater is continuously energized.

The ON-OFF cycle is repeated as described above, and when the temperature of the cooked rice inside the main body 5 falls below the operating temperature of the temperature sensor 4, the output of the temperature sensor 4 is reversed, the judging means 81 judges that the temperature is low, and the timer means 82 stops. Then, the energization control elements 83 are operated via the energization control means 83 to continuously energize the heat retention heaters 1 and 3. As a result, the calorific value increases from that during the ON-OFF cycle, the temperature of the cooked rice rises, and when the temperature exceeds the operating temperature of the temperature sensor 4 again, the energization by the ON-OFF cycle as described above is repeated again.

(Effects of the Invention) As described above, according to the present invention, two patterns of ON-OFF cycle and continuous energization are repeatedly switched by energizing the heat-retaining heater by the output of the temperature sensor. Compared with the one controlled by two patterns of energization and complete disconnection, the difference in the heat retention temperature (differential) can be made smaller, and the low heat generation heat retention dedicated to continuous energization as in the second conventional example It does not require both a heater and a high-heat-retention heater dedicated to intermittent energization. The same effect can be obtained with only a high-heat-retention heater, resulting in cost reduction and low cost and high-performance heat retention for general consumers. Type rice cooker can be provided.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a warming type rice cooker according to an embodiment of the present invention, and FIGS. 2 and 3 are circuit diagrams for controlling energization of a warming heater by a triac and a relay, FIG. 4 and FIG. FIG. 6 is a circuit diagram of the first conventional example in which the thermal reed switch and the temperature sensor of the warm rice cooker are used to control energization of the warming heater, and FIG. 6 is a circuit diagram of the second conventional example. 1, 3 ... Heat insulation heater, 4 ... Temperature sensor, 5 ... Main body,
8 ... Microcomputer, 81 ... Judgment means, 82 ... Timer means, 83 ... Energization control means, 11, 12 ... Energization control element.

Claims (4)

[Claims] 1. A rice cooker and a warming heater are provided in a bottomed tubular main body having an open top, and an inner pot removably accommodated in the main body and a main body upper opening are covered with the warming heater inside. In a heat retention type rice cooker having a lid provided, a temperature sensor (4) is provided inside the main body (5), and this temperature sensor
Judgment means (81) for judging whether the output of (4) is above or below a preset temperature, and according to the judgment result of this judgment means (81), the time counting operation is started and stopped, and the time counting result is validated or invalidated. The timer means (82) for judging, and the heating means (1) operated by the output of the judging means (81) and the timer means (82), means for energizing (3) to (3), and no further constitution, When the output of the judgment means (81) is below the preset temperature after the rice has been cooked and switched to the heat retention state, the timer means (82) is stopped or it is judged that the timer output is invalid and the energization control means (83) is used. Energization control element to operate (11)
Alternatively, while the heaters (1) and (3) are energized via (12), the timer means (82) is started or the timer output is enabled when the output of the judging means (81) is higher than a preset temperature. A heat retention type rice cooker characterized by having a configuration of repeating an ON-OFF pattern in which the heat retention heaters (1) and (3) are energized and disconnected via the energization control element (11) or (12). 2. The judgment means (81), the timer means (82), and the energization control means (83) are provided in a microcomputer (8), and a temperature sensor (4) and energization control elements (11), (12) are provided. ) Is connected to a microcomputer (8), which is the warm-type rice cooker of the first item. 3. The heat-insulating rice cooker according to claim 1, wherein the temperature sensor (4) comprises a multi-point temperature detecting element such as a thermistor or a single-point temperature detecting element such as a thermal reed switch. 4. The energization control elements (11), (12) are those which use mechanical contacts such as relays, or semiconductor type non-contact power control elements such as triacs. Insulated rice cooker.