JP3101860B2 - rice cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rice cooker provided with a power outage countermeasure.

[0002]

2. Description of the Related Art There is a rice cooker having a configuration as shown in FIG. In this device, a backup power supply (42) is connected to a power supply terminal of a microcomputer (41) incorporated in the control device (4), and a gas circuit to a gas burner (2) for heating the shuttle (1). The gas valve (20) inserted in the device is controlled by a control device (4). The output of the power failure detection device (3) for detecting the occurrence of a power failure is output from the microcomputer (41)
Monitored by

[0003] In this apparatus, a power failure detection device is provided during a rice cooking operation.
(3) When the power failure detection signal is output, the rice cooking operation is maintained in a stopped state. Thereafter, when the power failure is recovered and the power failure detection signal disappears, the remaining rice cooking operation after the stop of the rice cooking is continued again. If the power failure detection signal is repeatedly output from the power failure detection device (3) during a series of rice cooking operations from the start to the end of rice cooking and the number of outputs reaches the set number of times, the power failure is restored. Does not continue the remaining rice cooking operation. The number of times of the power failure detection signal is determined when the power failure detection signal occurs frequently, and the power failure detection device (3) or the microcomputer (4) that determines the output thereof.
This is because 1) may be out of order and a safe rice cooking operation thereafter cannot be guaranteed.

Incidentally, in the above-mentioned conventional device, a long time (for example, 7
In the case of a power outage of about a minute), rice grains deteriorate beyond the permissible range during the power outage (cooking operation is interrupted). In this case, continuation of rice cooking operation after power recovery is prohibited. This avoids the inconvenience of cooking rice that does not have acceptable quality. However, in the above-described conventional apparatus, when a short-time power failure, particularly an instantaneous power failure occurs repeatedly, the rice cooking operation may not be continued after the recovery from the power failure even though rice of acceptable quality can be cooked. There was a problem that it was not possible to perform a typical rice cooking control.

[0005] This is because even if a short-term power failure occurs, when the number of occurrences reaches a set number, the rice cooking operation is not continued thereafter. That is,
If the accumulated time is not long even if a very short momentary power failure occurs repeatedly, the rice grains do not change beyond the allowable range during the interruption of rice cooking at the time of the power failure, so in such a case, rice cooking is continued. Even cooked rice of acceptable quality. However, in the above conventional method, even if it is a momentary power failure, when the number of occurrences reaches the set number of times, the rice cooking is continually prohibited from continuing after the recovery from the power failure. The cooked rice will not be cooked,
It is not possible to control rice cooking rationally.

[0006] The present invention has been made in view of the above points, and is provided with a power failure detection device (3) for detecting the occurrence of a power failure.
When the power failure detection device (3) outputs a power failure detection signal, the rice cooker interrupts the rice cooking operation, and further determines whether it is necessary to continue rice cooking according to the condition at the time of power recovery from the disappearance of the power failure detection signal. In the case where the power failure detection signal is repeatedly output from the power failure detection device (3), under the condition that the rice of acceptable quality can be cooked, it is possible to continue the rice cooking operation after the recovery from the power failure and rational rice cooking. The task is to enable control.

[0007]

[Technical Means] The technical means of the present invention for solving the above-mentioned problems includes: a power failure time measuring means for measuring the duration of a power failure detection signal output by the power failure detection device (3); Power failure time accumulation means for accumulating each power failure duration measured by the power failure time measurement means for each of a plurality of power failures occurring during one rice cooking operation leading to the end, and allowing rice cooking after continuation of power failure recovery to be allowed Time comparison means for outputting a rice cook prohibition signal when the above-mentioned power failure accumulated time becomes longer than a reference time for judging whether or not rice of good quality can be cooked, and the rice cook prohibition signal is output from the time comparison means Only after that, the continuation of the rice cooking operation after the recovery from the power failure is prohibited. "

[0008]

The above technical means operates as follows. When the power failure detection device (3) outputs a power failure detection signal during rice cooking operation,
The power failure time measuring means operates until the power failure recovers when the signal disappears, and measures the duration of the power failure. Further, if a plurality of power failures occur during a series of rice cooking operations from the start to the end of rice cooking, the respective power failure durations measured by the power failure time measuring means are accumulated by the power failure time accumulating means. Then, if the cumulative power outage time is less than the reference time (the reference time for cooking rice of acceptable quality), the rice comparison prohibition signal is not output from the time comparing means. Continue to cook rice. That is, when the instantaneous power failure repeatedly occurs, if the accumulated time of each power failure time is equal to or less than the reference time, the remaining rice operation is continued after the power failure ends.

[0009] On the other hand, when the cumulative time (the output value of the power failure time accumulation means) of the duration of each power failure repeatedly generated becomes equal to or longer than the reference time, the time comparison means for comparing these two times outputs a rice cook inhibition signal. Then, when the power failure is restored under the condition that the rice cooking prohibition signal is output, the rice cooking operation is not continued. That is, when the above-described power failure accumulation time is long enough that rice of acceptable quality cannot be cooked even when the rice cooking operation is continued, the rice cooking operation is not continued after the power failure is restored, and the rice cooking stopped state is maintained.

[0010]

The present invention has the following specific effects. Even if instantaneous power failures occur repeatedly, if the rice of acceptable quality can be cooked, the rice cooking operation is continued after the power failure recovery, so it is determined whether the rice cooking should be continued according to the number of power failures. The rice cooking operation is not maintained in a forced stop state even though quality rice is cooked, and rational rice cooking control can be performed.

[0011]

Next, an embodiment of the present invention will be described.
As shown in FIG. 1, the voltage of the control power supply circuit (5) supplied from the power plug (50) is supplied to the power supply terminal (411) of the microcomputer (41) constituting the control device (4) and the power supply terminal (411). The power is supplied to a backup power supply (42) for backing up the microcomputer (41) when it occurs, and to a power failure detection device (3) for detecting the presence or absence of a power failure. The power failure detection device (3) includes a transistor (31) for monitoring the output of the control power supply circuit (5) and a fixed resistor (32) inserted in the collector circuit of the transistor (31). The voltage between the fixed resistor (32) and the transistor (31) is monitored by a power failure monitoring port (412) of the microcomputer (41).
Then, when the power failure detection device (3) outputs a power failure detection signal, this is determined by the microcomputer (41), and the rice cooking operation or the heat retention operation is forcibly stopped, thereby ensuring a safe state. I have.

The microcomputer (41) has a shuttle
(1) The output of the temperature sensor (10) for detecting the internal temperature and the outputs of the rice cooker switch (61), the heat retention switch (62) and the stop switch (63) are applied. In addition, the microcomputer (4
The output of 1) is applied to a gas valve (20) and a warming heater (23) inserted in a gas circuit to a gas burner (2), so that these gas valves (20) and the like are controlled. Has become.

In this device, when the power plug (50) is connected to an outlet (not shown), the microcomputer (41) receives power supply from the control power supply circuit (5), and the backup power supply (42) is The control power supply circuit
It is charged by electricity supply from (5). Further, since the output of the control power supply circuit (5) is applied to the base of the transistor (31) constituting the power failure detection device (3), the transistor (31) is turned on and the power failure monitoring port ( 412) is in a state where the “L” signal is applied.

A control program having the contents shown in the flow charts of FIGS. 2 and 3 is stored in the microcomputer (41). By executing the control program, a pre-cooking step (see FIG. 2) for ensuring an appropriate water content in the rice grains. A) and hook (1)
The main cooking process (B) to evaporate the water inside, the steaming process (C) to complete the pregelatinization of the rice grains, and the warming process
(D) are sequentially executed in this order.

When the microcomputer (41) starts to operate by supplying electricity from the control power supply circuit (5), step (70) in FIG. 2 is executed, and a series of rice cooking operations from the start to the end of rice cooking. The power failure time update value (H) used to calculate the cumulative value of the duration of a plurality of power failures that occurred during the operation is set to “0”. Rice cooker switch in steps (71) and (72)
The operation of (61) and the heat retention switch (62) is monitored, and if the rice cooker switch (61) is operated, the ignition device (22) is determined in step (73).
To burn the gas burner (2),
The heating control timer (T2) for measuring the execution time of the preliminary cooking step (A) described later is reset.

Next, the pre-cooking step (A) to the heat retaining step
(D) is performed. Hereinafter, the rice cooking operation will be described for each of the above steps. [Pre-cooking process (A)] Next, the temperature inside the pot (1) is controlled by controlling the combustion amount of the gas burner (2) while monitoring the temperature in the pot detected by the temperature sensor (10). Step (7) is maintained at 45 ° C. in the embodiment.
Execute 4). Further, the above step (74) is repeated until the heating control timer (T2) reaches 15 minutes while judging the presence or absence of a power failure by watching the output of the power failure detecting device (3), and if a power failure occurs during this heating operation, The control operation branches from step (75) to a power failure processing routine (77). If a power outage occurs,
The microcomputer (4
The operation of 1) is maintained, and the backup power supply (4
The output of the transistor (31) changes from the "L" state to the "H" state (power failure detection signal) due to the output of (2), and this state is applied to the power failure monitoring port (412). This allows the microcomputer (41) to determine the occurrence of a power failure. When a power failure occurs, the power supply voltage supplied from the drive power supply (not shown) to the gas valve (20) disappears, and the gas valve (20) is maintained in a closed state. Accordingly, the gas burner (2) is maintained in the fire extinguishing state during the power outage and the safe state is ensured.

The power failure processing routine (77) has the contents shown in FIG. 3. First, in step (771), a power failure time measurement timer (T1) as power failure time measurement means is reset. Next, in step (772), it is determined whether or not the power failure has been restored (the power failure detection device
(3) whether the output has returned from “H” to “L”). If the power outage continues, the power outage time measurement timer (T1)
If the output is less than 7 minutes (corresponding to the auxiliary reference time of claim 2), the power failure time update value (H) set to "0" in step (70) of FIG. Power failure accumulated time (power failure time update value (H) + power failure time measurement timer calculated as the sum of power failure time measurement timer (T1)
(T1) is determined to be 10 minutes or more, which is the reference time (see step (774)). If it is less than 10 minutes, the power failure is restored by repeating steps (772) to step (774). Calculate the cumulative power outage time until On the other hand, if it is confirmed that the power failure accumulated time is 10 minutes or more when executing the step (774), the control operation is stopped at the step (775) until the recovery from the power failure, and then the control operation is performed at the step (70) in FIG. )
Return to Therefore, the cumulative power failure time is equal to the reference time of 10
If the time is longer than a minute, the rice cooking operation is not continued even after the recovery from the power failure, and the inconvenience that the operation of cooking rice that does not satisfy the acceptable quality is wastefully executed is eliminated. In this embodiment, the functional unit in the microcomputer for executing the step (774) corresponds to the time comparing means described in the technical means.

If the output of the power failure time measurement timer (T1) is confirmed to be 7 minutes or more when the above-described step (773) is executed, the power failure is restored in step (775). Then, the control operation returns to step (70). Therefore, also in this case, the rice cooking operation is not continued after the recovery from the power failure. That is, even when a specific power failure continues for 7 minutes or more, the rice cooking operation is prohibited from continuing, and the operation of cooking rice that does not satisfy the acceptable quality is prevented. Even if a specific power failure continues for a predetermined period of time, the prohibition of rice cooking is prohibited only during the same cooking process such as the preliminary cooking process (A), the main cooking process (B), and the steaming process (C). This is because rice of acceptable quality cannot be cooked when the occurrence of occurs. Also, the reference time of the cumulative power failure time is set to a time of 10 minutes longer than the above-mentioned 7 minutes because a plurality of power failures occurred are a preliminary cooking process (A), a main cooking process (B), and a steaming process (C). ), The specific rice cooking process is rarely interrupted intensively, so rice of acceptable quality can be cooked even if the reference time of the cumulative power failure time is set to the above value. It is.

Next, when it is confirmed that the power failure has been recovered when step (772) in FIG.
In (776), the “power failure time update value (H) +
The power failure time measurement timer (T1) measurement time ”is stored again as the power failure time update value (H), and the time during which the preliminary cooking operation was interrupted due to the power failure (from the measurement time of the heating control timer (2) to the power failure time The calculation time is calculated by subtracting the measurement time of the measurement timer (T1) so that there is no difference in the execution time of the preliminary cooking step (A) depending on whether or not a power failure has occurred. In this embodiment, the power failure time update value
(H) to calculate step (776) and the function section in the microcomputer for executing step (776), and the power failure time update value (H) and the power failure time measurement timer (T1) as a precondition for executing step (774). The functional unit in the microcomputer for adding the output corresponds to the power failure time accumulating means described in the section of the technical means described above.

Next, when the above step (776) is executed, the control operation then shifts to step (78) in FIG.
The gas burner (2) is reburned to continue the pre-cooking step (A). That is, steps (74) to (76) are repeated, and when the pre-cooking time (set to 15 minutes in this embodiment) elapses, the pre-cooking step (A) is terminated. [Main cooking process (B)] In step (80), the gas burner (2) is burned with high heat. In step (81), the presence or absence of a power failure is determined. If a power failure occurs, the preliminary cooking process (A) described above is performed. A power failure processing routine (77) is executed in the same manner as described above. Meanwhile, step (81)
If a power failure does not occur when the process is executed, the temperature in the pot (1) detected by the ignition device (22) rises to the main cooking end temperature (set to 145 ° C. in this embodiment). Heat the gas burner (2) until [Steaming process (C)] In step (83), the gas burner (2) is burned at a low heat, and the heating control timer (T2) is set to "0".

Next, in steps (85) to (87), the power failure detection device
By monitoring the output of (3), while judging the presence or absence of a power failure, the inside of the pot (1) is steamed for the steaming time (set to 8 minutes in this embodiment) (98 ° C in this embodiment).
Set to). When the steaming time has elapsed, the steaming process (C) is terminated in step (88) by maintaining the gas burner (2) in the fire extinguishing state. If a power failure occurs during the steaming step (C), step (86)
Then, the control operation branches to a power failure processing routine (77), and power failure processing is performed in the same manner as in the preliminary cooking step (A) described above.

If the specific power failure occurring in the steaming step (C) continues for 7 minutes or more, or if the cumulative power failure time becomes 10 minutes or more, continuation of the rice cooking operation after recovery from the power failure is prohibited. Then, the cooked rice is left in a non-heated state. In such a case, the cooked rice is naturally steamed and brought into a predetermined cooked state. [Heat-retention step (D)] A heat-retention operation is performed in step (90) to cause the heat-retention heater (23) to generate heat to maintain the temperature in the pot (1) at the heat-retention temperature (68 ° C. in this embodiment). Then, if the stop switch (63) is operated during this warming operation, the control operation returns to step (70).

In the above embodiment, in the pre-cooking step (A), when a specific power failure continues for 7 minutes or more or when the cumulative power failure time becomes 10 minutes or more, the rice cooking operation after the recovery from the power failure is reset. Although the continuation is prohibited, in such a case, the remaining pre-cooking step (A) may be continued after the recovery from the power failure. That is, control may be performed in the same manner as when the specific power failure is less than 7 minutes or when the cumulative power failure time is less than 10 minutes. Because the heating temperature in the pre-cooking step (A) is low and the starch gelatinization of the rice grains does not start, the cooked rice can be cooked even if the pre-cooking step (A) is interrupted for a relatively long time.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a rice cooker according to an embodiment of the present invention.

FIG. 2 is a flowchart illustrating a control program stored in a microcomputer (41).

FIG. 3 is a flowchart illustrating a control program stored in a microcomputer (41).

FIG. 4 is an explanatory view of a conventional example.

[Explanation of symbols]

 (1) ・ ・ ・ Hook (2) ・ ・ ・ Gas burner (3) ・ ・ ・ Power failure detection device (4) ・ ・ ・ Control device

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) A47J 27/00 109

Claims (2)

(57) [Claims] A power failure detection device for detecting occurrence of a power failure (3)
When the power failure detection device (3) outputs the power failure detection signal, the rice cooking operation is interrupted, and further, it is determined whether or not to continue the rice cooking according to the condition at the time of restoration from the power failure when the power failure detection signal disappears. In a rice cooker, a power failure time measuring means for measuring the duration of the power failure detection signal output by the power failure detection device (3), and a plurality of times generated during one rice cooking operation from the start to the end of rice cooking. Power outage time accumulating means for accumulating each power outage duration measured by the power outage time measuring means for each of the power outages, and a criterion for judging whether or not rice of acceptable quality can be cooked by continuing rice cooking after the recovery from the power outage. A time comparison means for outputting a rice cook prohibition signal when the power failure accumulation time becomes longer than the time is provided, and only when the rice cook prohibition signal is output from the time comparison means, continues the rice cooking operation after recovery from the power failure. To ban Rice cooker. 2. The method according to claim 1, wherein when the power failure continuation time measured by the power failure time measuring means reaches an auxiliary reference time set shorter than the reference time, continuation of the rice cooking operation after the recovery from the power failure is prohibited. 1 rice cooker.