JP2000070123A - Pressure type electric rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply and safely release a lid in pressure rice cooking by reheating rice to be cooked to prevent a negative pressure in a pot even when the pressure drops within the pot during the period of steaming after the end of cooking rice. SOLUTION: This cooker is provided with a pot, a heating source, a mid lid having a pressure relief valve with which the pot is closed and released by operation from outside, a lid body with a pressurization mechanism which has a pressure relief button for operating the pressure relief valve and a timer means 18 to stop heating during the steaming by counting steaming time. A force heating means 25 is provided to reheat the rice to be cooked during a specified time before or after the counting of steaming time of the timer means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure-type electric rice cooker for cooking rice with a closed pot.

[0002]

2. Description of the Related Art When rice is cooked at a pressure higher than the atmospheric pressure in a pot containing rice and water, water is generated due to pressure from the start of cooking to the period of spotting after maintaining the boiling state. It can penetrate enough into rice grains and cook delicious rice in a short time. (Japanese Unexamined Patent Publication (Kokai) No. 6-22710) After the rice is eaten, after about 15 minutes of the simmering time after the end of the rice cooking, hot rice that has just been cooked is obtained.

[0003]

However, immediately after the completion of the cooking, the heating of the cooked rice is stopped and the above-mentioned 15-minute spotting is performed. Does not drop to atmospheric pressure during the 15 minute swing time.

[0004] Of course, if the mashing time is set to 20 minutes or more, the pressure in the pot gradually decreases and returns to the atmospheric pressure, but increasing the mashing time is the time required for eating rice. Is longer, which is not preferable.

[0005] As described above, when the rice cooked for 15 minutes and the steaming for 15 minutes are finished, the temperature in the pot decreases during the steaming, so that the air in the pot which has been expanded by high-temperature heating is cooled. There was a drawback that the inside of the pot became negative pressure and the lid came into close contact with the pot as it returned to its original state, and the lid could not be opened.

When the lid is actually opened, a pressure release button provided on the outside of the lid is formed by operating a pressure release button provided on the outside of the lid to constitute a part of the lid and closing the pot. The lid is opened after the high-pressure steam in the pan is released into the atmosphere by putting the inside of the pan in communication with the atmosphere, but as described above, when the inside of the pan is in a negative pressure state, the lid is placed on the pot side. Therefore, the pressure release valve and the pressure release button provided on the lid are relatively separated from each other, and even when the pressure release button is operated, the pressing force does not reach the pressure release valve, and the pressure release operation cannot be performed. .

According to the present invention, the cooked rice is heated again to increase the temperature in the pot when the pressure is reduced and the pressure in the pot is reduced during the rice cooker. This prevents the inside of the pan from becoming negative pressure and easily opens the lid.

[0008]

According to the present invention, there is provided a pot for storing cooked rice, a heating source for heating the cooked rice, and a hermetically closed pot which is driven by mechanical operation from the outside to make the inside of the pot and the atmosphere open. An inner lid having a pressure release valve communicating therewith, a lid having a pressure release mechanism provided above and openably on the inner lid for pressurizing the inner lid, and having a pressure release button provided facing the pressure release valve; The body, a timer means for starting to measure the time of rice after cooking and stopping heating of the cooked rice by the heating source during the clocking period, and a forced heating means for reheating the cooked rice by the heating source after the cooked rice is completed. The forced heating means starts reheating before the end of the measurement of the unevenness time by the timer means or during a predetermined time after the end of the time measurement.

[0009] Further, a pot for accommodating the cooked rice, a pressurizing mechanism for pressurizing the cooked rice, a heating source for heating the cooked rice, a lid for closing the cooked pot, and starting to measure the time of the rice drying after the cooked rice is completed. Timer means for stopping the heating of the cooked rice by the heating source during the time period; and forcibly heating means for reheating the cooked rice by the heating source after the completion of the rice cooking, wherein the forced heating means comprises:
The reheating is started before the end of the measurement of the unevenness time by the timer means or during a predetermined time after the end of the measurement.

[0010]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a flow chart of the pressure-type electric rice cooker of the present invention, FIG. 2 is a typical schematic block diagram when pressure cooking is performed by sealing the pot similarly, and FIG. 3 is different from FIG. FIG. 4 is a partial cross-sectional view of an embodiment in which a pressure relief valve provided on a lid is opened, and FIG. 4 is a partial cross-sectional view illustrating a rice cooking state in which the pressure relief valve is closed in the embodiment of FIG. Is a partial cross-sectional view of the embodiment of FIG. 3 in a state where the pressure release valve is opened by an external operation;
6 is a partial cross-sectional view of the embodiment of FIG. 3 in a state in which the inside of the pan has a negative pressure at the end of the washing process, and FIG. 7 is a pan bottom temperature common to the embodiments of FIGS. 2 and 3. FIG. 5 is a characteristic diagram showing a temperature in a lid, a pressure in a pot, and a heating timing of cooked rice.

(1) is a rice cooker main body, and (2) is a pot which is provided inside the rice cooker main body so as to be capable of being stored and stores a predetermined amount of rice and water.
(3) (3) (3) (3) is a heating source (hereinafter referred to as a coil) disposed close to the bottom outer surface of the pan (2);
Is a bottom sensor that contacts the outer bottom surface of the pan (2) to detect the temperature of the pan, and (5) a packing (6) provided on the outer peripheral edge is brought into close contact with the opening (7) of the pan (2). A lid for closing the pan, and a pressure relief valve (8) that opens when the pressure is equal to or higher than a predetermined pressure is provided in an appropriate place. (9) is a lid body provided above the lid (5) and provided with a pressurizing mechanism (10) for pressurizing the lid, and has a steam passage (12) projecting a lid sensor (11).

(13) a control unit comprising a microcomputer, an arithmetic processing unit (14), a first timer means (15),
A second timer means (16), a third timer means (18) having a subtraction processing means (17), and an input / output unit (1).
9) and (20) are provided. (21) is a rice cook start button for executing a rice cooking operation, (22) is a menu selection button for selecting the type of rice cooked, for example, white rice, brown rice, etc., and (23) is a button for the bottom sensor (4) and the lid sensor (11). Temperature detecting means for detecting temperature information and inputting it to the control unit (13);
4) means forcibly drying the cooked rice to a dry-up state by forcibly heating the cooked rice after maintaining the boiling state for a certain period of time, and (25) re-cooking the cooked rice before finishing the rice drying process after the cooked rice is finished. A forced heating means for heating, (26) a process indicator for displaying the progress of rice cooking by the output of the control unit (13), (27) a time indicator for displaying a rice drying time and a rice cooking reservation time, (28) Is the menu selection button (2
This is a selection indicator for displaying the menu selected in 2).

The first timer means (15) will be described in detail. This timer means has a time keeping time (T ₁ ) set at about 90 seconds, and the temperature detecting means of the bottom sensor (4) is 1
Time measurement is started after the detection of 00 degrees. During this time measurement, the temperature of the pot is reduced without heating the cooked rice.

That is, the temperature of the pot is measured when the clocking time (T ₁ ) has finished measuring the time, and the temperature during the boiling maintenance period and the temperature during the forced dry-up, which are the subsequent processes, are determined based on this temperature. Therefore, the temperature measurement data after the lapse of the clocking time (T ₁ ) becomes important.

[0015] With Shoki said second timer means (16), the timer means is fixed counting time (T ₂₎ for 20 minutes at which to set the boiling sustain period, the counting time (T ₂₎ is Upon completion, a forced dry-up operation for rapidly heating the cooked rice is performed.

In detail, the third timer means (18) starts counting the time (T ₃ ) after completion of the forced dry-up operation, and 15 minutes of the time (T ₃ ) In order to secure the irregularity time, the time measured by the arithmetic processing means (17) is 15 minutes.
When the starting point of the predetermined time (t) just before the end of the minute is counted, the cooked rice is heated by the subtraction forced heating means (25) to prevent the inside of the pot from becoming negative pressure. The predetermined time in this case is approximately 1
A time between 5 and 40 seconds is appropriate.

Next, the embodiment of FIG. 2 will be described with reference to FIGS. The pot (2) containing rice and water is housed in the rice cooker body (1), and the lid (5) is put on the opening (7) of the pot (2) to seal the lid (9). When the lid is closed, the pressing mechanism (10) presses the lid (5) one layer against the pan by the cover of the lid to bring it into a pressurized state.

Then, after operating the menu selection button (22), the cooker start button (21) is operated to operate the coil (3).
(3) Apply an inverter current to (3) and (3) to cause the pan (2) to generate heat by the ridge current flowing through the pan (2) to heat rice and water (S1, S2).

When the bottom sensor (4) detects about 60 degrees, an inverter current is intermittently applied to the coil to perform a preheating operation. When the preheating operation is completed, the inverter current to the coil is increased and the cooked rice is rapidly heated to perform the cooking operation, but the pan is operated by the pressure relief valve (8) and the pressurizing mechanism (10).
As a result, the pressure in the pot increases to about 1.2 atm.

Then, when the bottom sensor (4) detects about 70 degrees (S3), the temperature in the pot at this time has reached about 100 degrees, and the pot is in a boiling state. The output of the bottom sensor (4) starts measuring the time (T ₁ ) of the first timer means (15) and stops applying the inverter current to the coil (S4, S5).

[0021] During measurement of the measurement time (T _1), although the temperature of the cooking product to heat the cooking object is stopped continues to decrease, the measurement of the measurement time (T ₁₎ is completed, at which time Is measured and stored (S6).

Further, after the end of the clocking time (T ₁ ), the boiling maintaining step is started (S7, S8), and the clocking of the clocking time (T ₂ ) by the second timer means (16) is started (S7).
9) While the inverter current is intermittently applied to the coil based on the above-mentioned pot temperature, the boiling state is maintained at a temperature slightly higher than this pot temperature. During this time, since the heating of the cooked rice is intermittent, the pressure in the pot is maintained at about 1.1 atm according to the heating and stopping, and water is absorbed into the rice grains.

When the time (T ₂ ) measured by the second timer means (16) has elapsed (S10), the time-up signal at this time is immediately received and the forced dry-up means (2) is received.
4) is activated to rapidly heat the cooked rice in a short time to evaporate excess water in the pot, thereby finishing the rice cooking and proceeding to the washing process (S11, S12). The operation time of the forced dry-up is not shown, but may be short.

The period of the washing process (the washing time) is the time set by the third timer means (18). During this period, the heating of the cooked rice is basically stopped and (S1).
3) At the same time as the shift to the mura process, time measurement of the time measurement time (T ₃ ) is started (S14).

Eventually, when the counting of the clocking time (T ₃ ) progresses and the subtraction processing means (17) detects a time that is a predetermined time (t) earlier than the clocking end time (S15), the subtraction processing means (17) starts counting. The forced heating means (25) is activated by the output to heat the cooked rice to increase the temperature in the pot during a predetermined time (t) (S16). (Refer to the pressure characteristic diagram in the pot in FIG. 7) After the timing of the clocking time (T ₃ ) ends (the timing of the predetermined time t ends), the heating of the cooked rice is stopped, and the process shifts to the rice drying process (S).
17-19).

FIG. 7 is a graph showing pressure characteristics in the pot A and B shown in the characteristic diagram of FIG.
Represents a change when the forced heating for a predetermined time (t) is not performed as in the present invention at the time of the above-described unevenness step. A broken line A indicates a case where the amount of cooked rice is large, and B indicates a case where the amount of cooked rice is small If the amount of cooked rice is large, even if heating of the cooked rice is stopped, the temperature drop due to the residual heat of the cooked rice will slow down, so the rate of decrease in pressure in the pot will also be slow, but if the amount of cooked rice is small, Since the residual heat is low and the temperature decreases quickly, the pressure in the pot becomes negative before the end of the fluctuation time, and the lid (5) is attracted to the pot as shown by the arrow in FIG. (At this time, the lid cannot be opened.) FIGS. 3 to 6 show a more practical arrangement in which the pressure in the pot is released by operating a pressure release button provided outside the pot to release the pressure in the pot at the end of the mura process. This is an embodiment and will be described in detail below. The members having the same functions as those shown in FIG. 2 are denoted by the same reference numerals.

Reference numeral (29) denotes an inner lid for sealing the pot (2), which is provided with an engagement knob (30) at the center of the upper surface and is opened by being driven by a mechanical operation from the outside to communicate the inside of the pot with the atmosphere. A pressure relief valve (8) is installed.

The pressure relief valve (8) is located at a steam hole (31) provided in the inner lid (29) and has a valve plate (32) fixed at the lower part thereof, and a vertically movable valve rod (33). A receiving stand (35) having a relief hole (34) formed between the valve rod and the base,
A cylindrical case (36) surrounding the cradle and the valve rod (33);
The first interposed between the cradle (35) and the cylindrical case (36)
The upper part of the spring (37) and the valve rod (33) and the pedestal (3)
5) interposed between the first and second valve rods to constantly urge the valve rod upward.
And a spring (38).

Therefore, when the pressure in the normal pot is low, the valve plate (32) is in close contact with the cradle (35) by the second spring (38) to close the escape hole (34),
The cradle (35) is pushed down by the first spring (37) to close the steam hole (31).

(39) is an openable and closable lid which is pivotally supported on one side to the rice cooker main body (1) by a hinge. A steam vent (40) is provided at the center of the upper surface, and a pressure is provided on one side of the upper surface. A release button (41) is provided, and the engagement knob (30) is provided at the lower part.
And an engagement receiving portion (42) for engaging and holding the same, and one side is rotatably supported by a shaft (43) below the pressurizing mechanism (10) and the steam release button (41). Pressed pin (4
A movable plate (45) having 4) is provided. (46) is a packing provided and fixed between the movable plate (45) on the lower surface of the lid (39) and the pressure relief valve (8).

Reference numeral (47) denotes a lock button for holding the lid (39) provided on the upper portion of the side wall of the frame (48).

The operation of this embodiment will be described with reference to FIGS. 3 to 7. The basic operation from rice cooking to steaming is the same as that of FIG. 2 described above. Here, the operation of the pressure relief valve (8) and the operation in the pot are described. The displacement of the inner lid (29) due to the pressure described above is described.

Until the rice cooking operation starts and the inside of the pot reaches a certain pressure value, the valve plate (32) and the receiving stand (35) are in the state of FIG. 4 and the inside of the pot and the atmosphere are shut off.

When the rice cooking and rice roasting steps are completed and the pressure in the pan has dropped to about atmospheric pressure, when the pressure release button (41) is pressed as shown in FIG.
5) is pressed down, and the movable plate rotates while pressing the pressing pin (4).
4) pushes down the packing (46) and pushes down the valve rod (33) against the second spring (38) to push the valve plate (3).
2) is released from the cradle (35) to open the escape hole (34). With the opening of the escape hole (34), a slightly high pressure in the pot is applied to the escape hole (34), the inner lid (29) and the lid (39).
Is discharged into the atmosphere from the steam vent (40) through the space (S).

In the above operation, the inside of the pot is not at a negative pressure.
After the squeezing step, the inner lid (29) is at a predetermined position, so that the stroke of the movement of the pressing pin (44) of the movable plate (45) and the position of the valve rod (33) stop at the predetermined position. As a result, the pressure relief valve (8) can be opened.

However, FIG. 6 is an explanatory diagram in the case where the forced heating is not performed before the end of the unevenness step as described above. In this case, when the amount of cooked rice is small, it appears remarkably. Immediately after the end of the cooking process, the inner lid (29) is sucked toward the pot by a distance (H) from a predetermined position due to a negative pressure, so that the pressure release button (41) is used to release the pressure in the pot.
, The pressing pin (44) of the movable plate (45) does not reach the upper end of the valve rod (33) and the escape hole (34) cannot be opened.

The forced heating according to the present invention was performed during a predetermined time before the end of the rice-drying step to reheat the cooked rice and raise the temperature in the pot, but the rice-drying step was completed. Immediately after that, reheating may be performed for several tens of seconds.In this case, it is necessary to open the lid during reheating to prevent high-pressure steam from being released. For example, it may be displayed with contents such as “warming”.

[0038]

As described above, the present invention provides an inner lid having a pressure release valve for sealing the pan and opening it by mechanical operation from the outside to communicate the inside of the pan with the atmosphere, and provided above the inner lid. A pressure cooker provided with a lid having a pressurizing mechanism for the inner lid and a pressure release button for operating the pressure release valve, and performs rice cooking under pressure. Since the heating of the cooked rice is stopped to perform the murai step, and the cooked rice is reheated by the forced heating means during the predetermined time before or after the measurement of the murai time, Due to this reheating, the temperature in the pot rises and the inside of the pot does not become negative pressure, so that the force of the pressure release button is accurately transmitted to the pressure release valve and the pressure in the pot can be reliably released.

Further, the rice cooker also performs pressure cooking and includes a lid for sealing the pan and a pressurizing mechanism for pressurizing the pan. Similarly, for a predetermined time before or after the clocking of the unevenness time is completed. Since the cooked rice is re-heated by the forced heating means in between, the negative pressure in the pot is prevented and the lid can be easily opened. This configuration is not limited to an inner lid having a pressure relief valve and a lid having a pressurizing mechanism, in particular, and has a pressurizing mechanism for simply pressing the pan and a lid for sealing the pan. It suggests that even a pressure rice cooker can be put to practical use.

[Brief description of the drawings]

FIG. 1 is a flowchart of a pressure-type electric rice cooker according to an embodiment of the present invention.

FIG. 2 is a typical schematic block diagram in the case of pressure cooking rice with the pan closed as well.

3 is a partial sectional view of an embodiment in which a pressure relief valve provided on a lid for sealing a pan is opened by an external operation, similarly to FIG.

FIG. 4 is a partial cross-sectional view showing a rice cooking state in which the pressure relief valve is closed in the embodiment of FIG. 3;

5 is a partial cross-sectional view of the embodiment of FIG. 3 with the pressure relief valve opened by an external operation.

FIG. 6 is a partial cross-sectional view of the embodiment of FIG. 3 in a state in which the inside of the pot has a negative pressure at the end of the washing process.

FIG. 7 is a characteristic diagram showing the pot bottom temperature, the lid temperature, the pot pressure, and the heating timing of cooked rice, which are also common to the embodiments of FIGS. 2 and 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Rice cooker main body 2 Pot 3 Heat source (coil) 5 Lid 8 Pressure relief valve 10 Pressurizing mechanism 18 Timer means (third timer means) 25 Forced heating means 29 Middle lid 41 Pressure release button 39 Lid

Claims (2)

[Claims] 1. A cooker comprising a pot for accommodating cooked rice, a heating source for heating the cooked rice, and a pressure release valve for hermetically closing the pot and being driven by an external mechanical operation to communicate the inside of the pot with the atmosphere. A lid, a lid body having a pressure mechanism provided to be openable and closable above the inner lid and pressurizing the inner lid, and having a pressure release button provided to face the pressure release valve; A timer means for starting the time measurement and stopping the heating of the cooked rice by the heating source during the counting period, and a forced heating means for reheating the cooked rice by the heating source after the completion of the cooking,
The pressure type electric rice cooker, wherein the forcible heating means starts reheating before or after a predetermined time after the measurement of the unevenness time by the timer means. 2. A pot for accommodating the cooked rice, a pressurizing mechanism for pressurizing the pot, a heating source for heating the cooked rice, a lid for sealing the pot, and starting to measure the time of the muramura after the rice is cooked. Timer means for stopping the heating of the cooked rice by the heating source during the time period; and forcibly heating means for reheating the cooked rice by the heating source after the completion of the rice cooking, wherein the forced heating means is uneven by the timer means. A pressure-type electric rice cooker characterized in that reheating is started before or after a predetermined period of time has elapsed.