JP5273985B2 - rice cooker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rice cooker capable of cooking delicious rice in the same rice cooking time even when the rice is cooked under different rice cooking conditions in conformity with the change in the rice quality. <P>SOLUTION: In the rice cooker 1 for executing a rice cooking process including a water absorbing step of making a food to be cooked absorb water at a prescribed water absorbing temperature T and within water absorbing time TA, a start heating step of elevating the temperature and heating the food to be cooked taking prescribed start time TB, a boiling maintaining step of maintaining the food to be cooked in a boiling state over prescribed boiling maintaining time TC, and a steaming step of steaming the food to be cooked over prescribed steaming time TD by a control device, the time periods TA-TD for roughly fixing the time required for the rice cooking step are obtained beforehand and stored according to a season condition for cooking the rice in a storage device. When a four-season cooking menu is selected, the control device calls the time periods TA-TD corresponding to the season condition for cooking the rice, executes control so that the time for which the respective time periods are totaled is the practically same rice cooking time TE under any season condition, and executes the rice cooking process. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to a rice cooker equipped with a microcomputer. More specifically, the present invention relates to a rice cooker that can cook rice with the same cooking time even if it is cooked under different rice cooking conditions corresponding to rice of different quality.

  A recent rice cooker is equipped with a microcomputer, and by this computer, a water absorption step for absorbing a predetermined amount of water to the rice to be cooked, a rising heating step for heating the absorbed rice to be boiled, A rice cooking process such as a boiling maintaining process for maintaining the cooked rice in a boiling state and a steaming process for unevenly cooking the cooked food for a predetermined time is performed, and the user can select a favorite rice cooking menu and cook rice.

  However, the quality of rice changes with the passage of time after harvest. That is, rice is harvested at the beginning of the year, at the beginning of the year, during the winter, spring and summer when the new rice is harvested the following year, and at older rice. The quality is different. Therefore, when these different types of rice are cooked under the same cooking conditions, the cooked rice may not be cooked deliciously because its hardness, scent, etc. will change depending on the rice quality. On the other hand, user preferences have been diversified, and it has been demanded that the hardness, stickiness, sweetness, etc. of rice meet user preferences. Therefore, various types of rice cookers have been developed in order to solve such problems and respond to user requests (for example, see Patent Documents 1 and 2 below).

For example, the rice cooker disclosed in Patent Document 1 below stores a rice cooking sequence corresponding to the rice quality in advance in the storage means of the computer so that the user can select the rice cooking sequence corresponding to the rice to be cooked. It is. This rice cooking sequence is a basic rice cooking sequence, a rice cooking sequence for cooking new rice, and a rice cooking sequence for cooking old rice. Moreover, the rice cooker disclosed by the following patent document 2 changes the water absorption time in a water absorption process before and after that on the basis of summer.
JP-A-6-1333849 (FIG. 3, paragraphs [0015] to [0020]) Japanese Patent No. 2914224 (FIG. 10, paragraphs [0063] to [0064])

  According to the rice cooker disclosed in Patent Literature 1, rice cooking sequences corresponding to rice qualities such as new rice and old rice can be selected and cooked. Also, according to the rice cooker disclosed in Patent Literature 2 above. For example, the water absorption time is changed before and after summer, so you can cook deliciously even if the rice quality is different.

  However, when these rice cookers cook rice having different rice qualities, the rice cooking conditions in the rice cooking process, for example, the water absorption time in the water absorption process, the startup power in the startup heating process, and the vertical Upper time, boiling maintenance power and boiling maintenance time in the boiling maintenance process, unevenness time in the unevenness process, etc. are set, respectively, among these conditions, the rice cooking time that totals the time required for each process is also rice quality Each difference is different. Therefore, depending on the user, the rice cooking time may vary depending on the season when the rice quality changes, and the rice cooker can be cooked with the same cooking time throughout the year and can be cooked deliciously. Is desired. Of course, rice with different rice quality can be cooked with the same cooking time, but even if the cooking time is the same, the cooking conditions differ depending on the quality of the rice, so it cannot be cooked deliciously. In other words, when cooking rice with altered rice quality, new rice is generally soft and sticky, and summer rice is hard and crisp, so you cannot cook similar rice throughout the year. . In addition to the adjustment of the hardness, there is a demand for a product that can adjust other tastes such as sweetness, stickiness, umami, aroma, elasticity, and gloss.

  Therefore, the present invention has been made in order to meet such user requirements, and the object of the present invention is to be delicious in the same cooking time even when cooking under different cooking conditions corresponding to rice having different rice quality. The object is to provide a rice cooker that can be cooked.

In order to achieve the above object, a rice cooker according to claim 1 of the present application is a heating means for heating a pot into which a rice to be cooked is put, an opening in which the pot is accommodated, and a rice to be cooked in the pot. A rice cooker body having a lid, an openable / closable lid that closes the opening of the rice cooker body, storage means for storing various rice cooking menus, and a control device that executes a predetermined rice cooking process, and the control device In accordance with the rice cooking menu, the water-absorbing step of controlling the heating means to absorb the predetermined water in the cooked rice in the pan at the predetermined water-absorbing temperature T and the water-absorbing time TA, and the cooked rice to be absorbed Is heated for heating up to a predetermined time TB until boiling, a boiling maintaining process for maintaining the cooked rice in a boiling state for a predetermined boiling time TC, and cooked rice after the boiling maintaining process Unevenness process for unevenness of objects for a predetermined unevenness time TD In rice cooker to perform cooking process including, in the storage means, the water absorption time period required for the cooking process depending on the season condition for cooking is substantially constant TA, rise time TB, boiled maintenance time TC The unevenness time TD is obtained and stored in advance, and the control device calls the water absorption time TA, the rise time TB, the boiling maintenance time TC, and the uneven time TD corresponding to the seasoning conditions for cooking rice. In addition, the rice cooking process is performed by controlling the time obtained by adding the respective times so as to be substantially the same rice cooking time TE in any seasonal condition.

  The invention of claim 2 of the present application is the rice cooker according to claim 1, wherein the water absorption time is TAn, the rise time is TBn, the boiling maintenance time is TCn, and the unevenness time is TDn, When the season for cooking rice is autumn, winter, spring and summer, an integer of n = 1 to 4 is assigned in order, and is set so as to satisfy the relationship of the following expressions (1) to (4) .

TAn = constant (1)
TB ₁ <TB ₂ <TB ₃ <TB ₄ (2)
TC ₁ > TC ₂ > TC ₃ > TC ₄ (3)
TDn = TE− (TAn + TBn + TCn) (4)
The invention of claim 3 of the present application is the rice cooker according to claim 1, wherein the water absorption time is TAn, the rise time is TBn, the boiling maintenance time is TCn, and the unevenness time is TDn, When the season for cooking rice is autumn, winter, spring, and summer, an integer of n = 1 to 4 is assigned in order, and is set so as to satisfy the relationship of the following expressions (1) ′ to (4) To do.

TA ₁ <TA ₂ <TA ₃ <TA ₄ (1) '
TB ₁ <TB ₂ <TB ₃ <TB ₄ (2)
TC ₁ > TC ₂ > TC ₃ > TC ₄ (3)
TDn = TE− (TAn + TBn + TCn) (4)
Moreover, invention of Claim 4 of this application WHEREIN: In the rice cooker of Claim 2 or 3, when the said water absorption temperature is set to Tn and the seasons to which the said rice is cooked are autumn, winter, spring, and summer, n = in order, respectively. It is characterized by assigning integers 1 to 4 and satisfying the following relationship (5).

T ₂ > T ₁ > T ₃ > T ₄ (5)

  By providing the above configuration, the present invention has the following excellent effects. That is, according to the invention of claim 1, the rice quality changes with the passage of the month and day after harvesting, and the preferred water absorption process in the rice cooking process, the rising heating process, the boiling maintenance process, and the rice cooking conditions in the spotting process However, even if these rice cooking conditions are different, it is possible to cook deliciously with the same overall cooking time in all seasons throughout the seasons.

  Moreover, according to invention of Claim 2, the water absorption time in a water absorption process can be made constant, and it can cook deliciously by the same rice cooking time also in any seasonal conditions.

Further, according to the invention of claim 3, the water absorption time in the water process to correspond to the season, by the _{TA 1 <TA 2 <TA 3} <TA 4, rice throughout the year, delicious rice in the same cooking time can do. In particular, new rice can be hardened with less stickiness, while summer rice is sticky and can be cooked softly.

According to the invention of claim 4, the water absorption temperature in the water absorption process corresponds to the season, and T ₂ > T ₁ > T ₃ > T ₄ , so that the water absorption is performed at an optimum temperature according to the seasonal condition. Because it can do so, the rice can contain enough water, so you can cook delicious rice in the same cooking time throughout the season.

  Hereinafter, the best embodiment of the present invention will be described with reference to the drawings. However, the embodiment shown below exemplifies a rice cooker for embodying the technical idea of the present invention, and is not intended to specify the present invention for this rice cooker. Other embodiments within the scope are equally applicable.

  With reference to FIGS. 1-4, the structure of the rice cooker which concerns on embodiment of this invention is demonstrated. 1 shows a rice cooker according to an embodiment of the present invention, FIG. 1 (a) is a front view of the rice cooker, FIG. 1 (b) is an enlarged view of the display portion of FIG. 1 (a), and FIG. FIG. 3 is an enlarged cross-sectional view in which the outer case of the rice cooker in FIG. 1 is omitted, FIG. 3 is an enlarged cross-sectional view in which the pressure valve opening mechanism in FIG. 2 is enlarged, and FIG.

  As shown in FIG. 1 and FIG. 2, the rice cooker 1 has a pan 7 into which the rice to be cooked is put, an opening in which the pan 7 is accommodated above, and an inner portion in which the pan 7 is heated to prepare the cooked rice. A rice cooker main body (hereinafter referred to as a main body) 2 having heating means 5 for heating, and a lid body 10 having a locking mechanism pivotally supported on one side of the main body 2 to cover the opening and lock in a closed state; A pressure valve 13 that is attached to the lid 10 and adjusts the internal pressure in the pan 7, a pressure valve opening mechanism 18 that controls the pressure valve 13, a display operation unit 25 that displays and selects various rice cooking menus, And a control device 24 for controlling the heating means 5 and the pressure valve opening mechanism 18 according to the selected rice cooking menu.

  The main body 2 includes a bottomed box-shaped outer case 3 and an inner case 4 accommodated in the outer case 3 and in which the pan 7 is accommodated. A gap is formed between the outer case 3 and the inner case 4. A control circuit board or the like (not shown) that forms the control device 24 is formed in the gap. The inner case 4 is provided with a heating means 5 at the bottom 4a and side 4b, and a pan bottom temperature sensor 6 comprising a thermistor for detecting the pan bottom temperature at the bottom 4a. As the heating means 5, an electromagnetic induction coil wound in a donut shape is used. The pan 7 is made of a relatively deep bottom container into which a predetermined amount of cooked rice made of water and rice is put, and is made of, for example, a clad material of aluminum and stainless steel.

  As shown in FIGS. 2 and 3, the lid body 10 includes an inner lid 11 that closes the opening of the pan 7, an outer lid 12 that closes the entire opening of the main body 2, and the like. One end of the lid 10 is pivotally supported by one end of the main body 2, and the other end is locked to the other end of the main body 2 by a locking mechanism. A pressure valve 13 and a pressure valve opening mechanism 18 for opening the pressure valve 13 are provided on the upper portion of the inner lid 11. As shown in FIG. 3, the pressure valve 13 includes a valve seat 15 in which a valve hole 14 having a predetermined diameter is formed, and a metal ball 16 placed on the valve seat 15 so as to close the valve hole 14. And a cover 17 that restricts the movement of the ball 16 and holds the ball 16 on the valve seat 15.

  The pressure valve opening mechanism 18 is composed of a solenoid, a cylinder 19a around which an electromagnetic coil is wound, a plunger 19b that moves inside the cylinder 19a by excitation of the electromagnetic coil, and moves the ball 16, and a tip of the plunger 19b. It is composed of a mounted spring and an operating rod 20. The pressure valve opening mechanism 18 is controlled by the control device 24. That is, when the electromagnetic coil is excited based on a command from the control device 24, the plunger 19b jumps out of the cylinder 19a and collides with the ball 16, and pushes the ball 16 in the lateral direction. By this extrusion, the ball 16 is moved from above the valve hole 14 to forcibly open the valve hole 14. Further, in this open state, when the excitation to the electromagnetic coil is stopped, the plunger 19b is pulled back into the cylinder 19a by a spring force, and this retraction eliminates the force that the plunger 19b pushes the ball 16 in the lateral direction. 16 returns onto the valve hole 14, and the valve hole 14 is closed by the ball 16. The inner lid 11 is provided with a safety valve 22 for releasing the steam in the pan 7 to the outside through the steam port 21 when the pressure in the pan rises to an abnormal pressure equal to or higher than a predetermined pressure. Further, a steam temperature sensor 23 (see FIG. 3) is attached to the inner lid 11. The outer lid 12 is detachably mounted with a storage tank that stores rice balls that are ejected from the pan 7 during rice cooking. A steam hole 21 for discharging steam to the outside is formed in this tank.

  Various types of rice cooking menus are displayed on the front wall of the main body 2, and a display operation unit 25 including a plurality of operation buttons for setting a predetermined menu or the like from the displayed menus is provided.

  As shown in FIG. 1, the display operation unit 25 includes a display panel 8 on which various rice cooking selection menus and times are displayed, and a plurality of switch operation buttons 3 a to 3 f on the left and right and below the display panel 8. 9 is disposed. These operation buttons include a rice cooking / start button 3a for operating the rice cooker, a rice cooking reservation button 3b for making a rice cooking reservation, a cut / removal button 3c for canceling the setting of rice cooking, a rice selection button 3d for selecting rice, and a rice cooking menu. A menu selection button 3e for selecting a course, a course button 3f for selecting a course, and a cross-shift key 9 for selecting and determining a menu or the like displayed on the display panel 8. These buttons and keys are operation buttons or the like constituting a push button type switch, and each switch (not shown) is operated by pressing this button or key. Among these operation buttons 3a to 3f, the menu selection button 3e is used to display various rice cooking menus on the display panel 8. When this button is pressed, the menu selection button 3e is usually used for softening, softening, porridge, sushi, curry, A rice cooking menu such as cooking, rice, rice cake, etc. is displayed. The rice selection button 3d is used to select the type of rice, for example, one of white rice, non-washed rice, brown rice, germinated brown rice, and the like. Furthermore, the course button 3f is used to select umami warming, good night warming, cleaning, and the like. The cross-shift key 9 is used to select a predetermined menu from various menus displayed on the display panel 8. The displayed rice cooking menu, for example, normal, sautéed, soft, porridge, sushi, curry, The selection is performed by moving the cursor (blinking display) up and down and left and right by operating the cross shift key 9 from mochi mochi, seasonal cooking (spring, summer, autumn, winter) and the like. Spring, summer, autumn, and winter displayed on the display panel 8 are used to cook delicious rice throughout the year.

  As shown in FIG. 4, the control device 24 includes hardware including a circuit board on which a CPU, a ROM, a RAM, and the like are mounted, a rice cooking / start button 3a, a menu selection button 3e, a rice cooking reservation button 3b, and a cut / removal button. A button 3c, a rice selection button 3d, a course button 3f, a temperature sensor including a pan bottom temperature sensor 6 and a steam sensor 23 are connected to each other, and signals from these buttons and sensors are input to the CPU. . The CPU is connected to various timers for measuring a predetermined time and storage means ROM and RAM. Further, a heater (IH coil) 5, a pressure valve opening mechanism 18, a display panel 8, and the like are connected to the output unit (driver). The ROM stores various cooking menus and programs for executing the menus.

  Next, with reference to FIG. 5, the outline of the rice cooking process common to each rice cooking menu is demonstrated. In addition, FIG. 5 is explanatory drawing which showed the temperature in a pan in a rice cooking process, and the opening / closing pattern of a pressure valve.

  A rice cooking process common to various rice cooking menus is a water absorption process I in which a predetermined amount of water is absorbed by the rice at a predetermined water absorption temperature T and water absorption time TA, and startup of heating the cooked rice to a boiling temperature Y after water absorption. A heating process II, a boiling maintenance process III for maintaining a TC boiling state for a predetermined time with a predetermined boiling maintenance power, and rice cooked after completion of the boiling maintenance process III for a predetermined time TD unevenness IV ing.

  Among these, in the rising heating process II, the pressure valve 13 is closed, and the cooked rice is heated to the boiling temperature Y. By closing the pressure valve 13, the pressure in the pan is increased from atmospheric pressure to 1.2 atm. Moreover, in the boiling maintenance process III, the pressure valve 13 is closed after the pressure valve 13 is repeatedly opened and closed at a predetermined interval. When the pressure valve 13 is opened, the pressure in the pan 7 is reduced from 1.2 atm to nearly atmospheric pressure. This pressure change causes a so-called bumping phenomenon in which the inside of the pan 7 boils violently. Due to this bumping phenomenon, the rice grains in the pan 7 are agitated. In particular, when the pressure valve 13 is opened and closed at the initial stage of the boiling maintenance process III, the rice grains are efficiently stirred because the water in the pan 7 is increased at this stage. Moreover, in the latter half of this boiling maintenance process III, the water | moisture content in the pan 7 runs out, and temperature reaches the maximum value, ie, rice cooking temperature Z (130 degreeC). By detecting this rice cooking temperature Z, the boiling maintenance process III is completed.

  After the boiling maintenance step III, the process is shifted to the unevenness step IV. The unevenness step IV is performed after the completion of the boiling maintenance step III and after the completion of the unevenness 1. It consists of additional cooking and Murashi 2 (second half of Murashi) for finishing. In addition, the inside of the pan is heated and heated by additional cooking to remove unnecessary moisture.

  Although this rice cooking process allows rice to be cooked in various rice cooking menus, the quality of rice to be cooked varies depending on the season. In other words, the harvested rice is fresh rice in the autumn immediately after harvesting, the rice in the winter after a short period of time, the rice in the spring and the rice in the summer, and the rice quality in these four seasons has changed. When rice is cooked, its properties, such as hardness, softness, adhesion, adhesiveness, chewability, elasticity, balance, cohesiveness, and sustainability, change depending on the seasons. For example, in terms of the hardness of rice, fresh rice in the harvest season October is the lowest, then gradually rises toward winter, spring and summer, and reaches the highest value around September of the following year. Therefore, since the new rice around October has the lowest hardness compared to other season rice, when this new rice is cooked in the normal rice cooking process, it becomes soft and watery. Further, stickiness is considered to be the highest in rice in February in winter, followed by new rice in October, and lower in other seasons when the stickiness of rice is regarded as the degree of distraction. Therefore, the winter season and new rice are highly sticky. Furthermore, adhesive force, chewability, elasticity, balance, cohesion and sustainability are also changing.

  Thus, the harvested rice has its hardness, softness, adhesion, stickiness, chewability, elasticity, balance, cohesiveness, persistence, etc. changed with the passage of the month and day. Therefore, when cooking rice with different rice quality, for example, new rice, it becomes soft and sticky rice, while when cooking rice in summer, it becomes hard and crunchy rice, which may not match the taste of the user is there. On the other hand, rice around February in the winter season is cooked more deliciously than other seasons because it has higher hardness, adhesion, stickiness, chewing, elasticity, balance, cohesion and sustainability. . Therefore, in the four-season cooking in the rice cooker 1 of the present embodiment, the new rice is hardened by suppressing the stickiness, while the rice in the summer is sticky and soft so that it is finished to the same rice throughout the year. , So that you can cook in the same cooking time in any season.

  Next, rice cooking conditions for the four seasons will be described with reference to FIGS. 6 (a) and 6 (b) are temperature curve diagrams showing the temperature in the pan in the rice cooking process in autumn and winter, and FIGS. 7 (a) and 7 (b) are rice cooking in spring and summer. FIG. 8 is a table summarizing the water absorption time, the rise time, the boiling maintenance time, and the unevenness time in autumn, winter, spring and summer, showing the temperature in the pot in the process.

In the storage means ROM and RAM of the control device 24, the rice cooking conditions in the rice cooking process are set for every four seasons of spring, summer, autumn and winter. In the autumn season, as shown in FIG. 6A, the water absorption temperature T in the water absorption process I is T ₁ , the water absorption time TA is TA ₁ , the startup time TB in the startup heating process II is TB ₁ , and in the boiling maintenance process III. The boiling maintenance time TC is set to TC ₁ , and the unevenness time TD in the unevenness process IV is set to TD ₁ . Similarly, in winter, as shown in FIG. 6B, the water absorption temperature T is T ₂ , the water absorption time TA is TA ₂ , the rise time TB is TB ₂ , the boiling maintenance time TC is TC ₂ , and the uneven time TD. a is set to TD _2. In spring, as shown in FIG. 7A, the water absorption temperature T is T ₃ , the water absorption time TA is TA ₃ , the rise time TB is TB ₃ , the boiling maintenance time TC is TC ₃ , and the unevenness time TD is TD _3. Set to In the summer, as shown in FIG. 7B, the water absorption temperature T is T ₄ , the water absorption time TA is TA ₄ , the rise time TB is TB ₄ , the boiling maintenance time TC is TC ₄ , and the unevenness time TD is TD ₄ . Is set.

Therefore, in order to make the cooking time in the autumn, winter, spring and summer substantially the same time TE, the water absorption time TA, the rise time TB, the boiling maintenance time TC and the unevenness time TD are determined in the autumn, winter, spring and summer seasons. Allotted to the time of adjustment. In this adjustment, the water absorption time TA is set to the same time, for example, 15 minutes in autumn, winter, spring, and summer (TA ₁ , TA ₂ , TA ₃ , TA ₄ ). The rise time TB is set to a relationship of TB ₁ <TB ₂ <TB ₃ <TB ₄ . With this setting, a time difference occurs between the respective times, that is, between the times TB ₂ and TB ₁ , TB ₃ and TB _2, TB ₄ and TB ₃ , and the longest time TB ₄ and the minimum time. There is a maximum time difference ΔTB with respect to TB ₁ . Further, the boiling maintenance time TC is set to a relationship of TC ₁ > TC ₂ > TC ₃ > TC ₄ . With this setting, a maximum time difference ΔTC occurs between the longest time TC ₁ and the minimum time TC ₄ . If the above time differences ΔTB and ΔTC occur in the rise time TB and the boiling maintenance time TC in autumn, winter, spring and summer, the total process time until the boiling maintenance process III ends will cause a time difference in each season. The time difference is absorbed by the unevenness time TD of the next unevenness step IV, and the entire rice cooking time TE is set to be substantially the same. That is, assuming that the unevenness time in autumn, winter, spring and summer is TDn, the unevenness time TDn is set to a time obtained by subtracting (TAn + TBn + TCn) from the constant rice cooking time TE. Note that n is one of 1 (autumn), 2 (winter), 3 (spring), and 4 (summer). Thereby, delicious rice can be cooked with the same rice cooking time TE through the four seasons. By setting these conditions, the new rice can be cooked to the same rice throughout the year, making the rice less sticky and firm, while the summer rice is sticky and soft.

  Next, with reference to FIGS. 9-11, the rice cooking process of a four-season cooking menu is demonstrated. In addition, FIGS. 9-11 is a flowchart of a four-season rice cooking process. Various rice cooking menus are displayed on the display panel 8, but only the rice cooking process in which the four-season cooking menu is selected will be described below.

  First, before starting the rice cooking menu, a predetermined amount of water and rice are put into the pan 7, this pan is accommodated in the inner case 4, the upper lid 10 is closed and locked to the main body 2 to lock ( Step S101). In the next step S102, a rice cooking course is selected, and it is determined whether or not seasonal cooking is selected (S103). In addition, when seasonal cooking is not selected, it transfers to the rice cooking process by another rice cooking menu. Since the rice cooking process other than season cooking is not directly related to the present invention, the description thereof is omitted.

  When seasonal cooking is selected, seasonal processing settings are performed in step S104. This setting process is performed in the process shown in FIG. That is, referring to the calendar stored in the rice cooker in step S201, the current four seasons at the time of cooking are derived, and the four season setting screen is displayed on the screen of the display panel 8 (S202). If rice cooking is to be performed in the current four seasons during rice cooking, the start button 3a is pressed (Yes in S203), and the current four season settings are reflected in step S204. On the other hand, when cooking is not performed with the current four season settings, for example, when the current season is the boundary between the four seasons and the four seasons to be cooked are selected according to the user's preference, the start button 3a is not pressed (No in S203). In step S205, the four season setting can be changed by pressing the left and right buttons of the cross-shift key 9 (S206). Next, when the left and right buttons of the cross shift key 9 are not pressed, or when the four season setting is changed, the four season setting selected by pressing the start button 3a in step S207 is reflected (S208). If the start button 3a is not pressed (S207), this step is repeated.

  Next, when the four seasons for cooking rice are determined, the rice cooking conditions corresponding to the four seasons in step S209, ie, the water absorption temperature Tn, the water absorption time TAn, and the rise time TBn in the autumn, winter, spring and summer seasons as shown in FIG. And the boiling maintenance time TCn is set. These values are selected and set from the data stored in the storage means ROM and RAM. In step S210, the unevenness time TDn is calculated.

Of the four seasons, when autumn is set, the water absorption temperature in the autumn is T ₁ , the water absorption time is TA ₁ , the rising heating time is TB _1, and the boiling maintenance time is TD ₁ . Hereinafter, the rice cooking process in which autumn is set will be described.

In the rice cooking process in autumn, energization of the heaters 5a and 5b is started with the pressure valve 13 closed in step S105, and the pressure valve 13 is opened (S106). The water absorption temperature T corresponding to the autumn season. _The water absorption process I multiplied by the water absorption time TA in ₁ is executed (S107). In the water absorption step I, counting of the water time ST1 is continued until the fall of the water time TA ₁ in water timer. Further, within this water absorption time TA ₁ , the pot bottom temperature SK1 is detected by the pot bottom temperature sensor 6, and the temperature of each heater 5a, 5b is controlled and adjusted to the water absorption temperature T ₁ in autumn (S108 to S112).

Thereafter, the process proceeds to the start-up heating process II. In the start-up heating step II, it is closed pressure valve 13 is heated at full power over autumn rise time TB ₁ (S113~S116). Subsequently, in the boiling maintain step III, Fall boiling maintained time TC ₁ over a heater 5a, the opening and closing of the current and the pressure valve 13 to 5b is performed at predetermined time intervals (S117~S122). Specifically, the opening and closing of the pressure valve 13 is performed once to several times in the initial stage of this process. As the pressure valve 13 is opened, the pressure in the pan 7 is reduced from 1.2 atm to almost atmospheric pressure. A bumping phenomenon occurs due to this pressure change, and the rice grains in the pan 7 are stirred. In particular, when the pressure valve 13 is opened and closed in the initial stage of the boiling maintenance process III, the rice grains are efficiently stirred because the water in the pan is increased at this stage. On the other hand, energization of the heaters 5a and 5b is turned on / off in synchronization with the opening and closing of the pressure valve 13. Then, when the boiling maintenance time TC ₁ in the autumn has elapsed, the heating is stopped (S123).

In the next steaming step IV, by stopping the energization of the heater 5a, 5b, and unevenness of the fall running steaming by time TD ₁ multiplied terminates the cooking (S124~S127). After the completion of cooking, the process proceeds to a heat retaining process (S128).

  As explained above, according to the present embodiment, the time difference between the rise time TB and the boiling maintenance time TC is absorbed by the uneven time TD of the next unevenness process, and the entire rice cooking time TE can be set to be the same. . That is, assuming that the unevenness time in autumn, winter, spring and summer is TDn, the unevenness time TDn is set to a time obtained by subtracting (TAn + TBn + TCn) from the constant rice cooking time TE. Note that n is 1 (autumn), 2 (winter), 3 (spring), and 4 (summer). Thereby, delicious rice can be cooked with the same rice cooking time TE through the four seasons. By setting these conditions, the new rice can be cooked to the same rice throughout the year, making the rice less sticky and firm, while the summer rice is sticky and soft.

In the above embodiment, the water absorption time TA in the autumn, winter, spring and summer is the same. However, the water absorption time TA is varied depending on the state of rice, so that TA ₁ <TA ₂ < It is preferable to make TA ₃ <TA ₄ and adjust the unevenness time so that the entire rice cooking time TE becomes the same, because a water absorption process more suited to the state of rice can be performed. Further, the water absorption temperature T may satisfy T ₂ > T ₁ > T ₃ > T ₄ . Moreover, a rice cooker is not limited to a pressure type thing.

FIG. 1: shows the rice cooker which concerns on embodiment of this invention, FIG. 1 (a) is a front view, FIG.1 (b) is an enlarged view of the display part of Fig.1 (a). FIG. 2 is a longitudinal sectional view in which the outer case and the like of the rice cooker in FIG. 1 are omitted. FIG. 3 is an enlarged cross-sectional view of the pressure valve opening mechanism of FIG. 4 is a control block diagram of the control device. FIG. 5 is an explanatory view showing the temperature in the pan and the opening / closing putter of the pressure valve in the rice cooking process of the common rice cooking menu. 6 (a) and 6 (b) are temperature curve diagrams showing pan bottom temperatures in the rice cooking process in autumn and winter. FIG. 7A and FIG. 7B are temperature curve diagrams showing the pot bottom temperature in the rice cooking process in spring and summer. FIG. 8 is a table summarizing the water absorption time, rise time, boiling maintenance time, and unevenness time in autumn, winter, spring and summer. FIG. 9 is a flowchart showing the rice cooking process of the rice cooker according to the embodiment of the present invention. FIG. 10 is a flowchart of the rice cooking process following FIG. FIG. 11 is a flowchart of the rice cooking process of the four season setting process in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rice cooker 2 Main body case 3 Outer case 4 Inner case 5 Heating means 6 Pan bottom temperature sensor 7 Pan 8 Display panel 9 Cross shift key 10 Lid 11 Inner lid 12 Outer lid 13 Pressure valve 14 Valve hole 15 Valve seat 16 Ball 17 Cover 18 Pressure valve opening mechanism 19a Cylinder 19b Plunger 20 Operating rod 21 Steam port 22 Safety valve 24 Control device 25 Display operation unit

Claims (4)

A rice cooker body having a pan into which the cooked rice is charged, an opening in which the pan is stored, and a heating means for heating the cooked rice in the pan, and an openable / closable lid that closes the opening of the cooker body Body, storage means for storing various rice cooking menus, and a control device for executing a predetermined rice cooking process,
The control device controls the heating means according to the rice cooking menu to absorb the predetermined water in the cooked rice in the pan at the predetermined water absorption temperature T and water absorption time TA, and the water absorption A rising heating step of heating and heating the cooked rice until it boils over a predetermined rise time TB, a boiling maintaining step of maintaining the cooked rice in a boiling state for a predetermined boiling time TC, and the boiling maintaining step In a rice cooker that performs a rice cooking process including a predetermined unevenness time TD unevenness process, and a rice cooking process later,
In the storage means , the water absorption time TA, the rising time TB, the boiling maintenance time TC, and the unevenness time TD in which the time required for the rice cooking process is substantially constant according to the seasoning conditions for rice cooking are obtained and stored in advance. Every
The control device calls the water absorption time TA, the rising time TB, the boiling maintenance time TC, and the unevenness time TD corresponding to the seasonal conditions for cooking rice, and the sum of the respective times is any seasonal condition. However, the rice cooker is characterized in that the rice cooking step is executed under control so that substantially the same rice cooking time TE is obtained. When the water absorption time is TAn, the rise time is TBn, the boiling maintenance time is TCn and the unevenness time is TDn, and the cooking season is autumn, winter, spring and summer, n = 1 to 1 respectively. The rice cooker according to claim 1, wherein an integer of 4 is assigned and set so as to satisfy the relationship of the following expressions (1) to (4).
TAn = constant (1)
TB ₁ <TB ₂ <TB ₃ <TB ₄ (2)
TC ₁ > TC ₂ > TC ₃ > TC ₄ (3)
TDn = TE− (TAn + TBn + TCn) (4) When the water absorption time is TAn, the rise time is TBn, the boiling maintenance time is TCn and the unevenness time is TDn, and the cooking season is autumn, winter, spring and summer, n = 1 to 1 respectively. The rice cooker according to claim 1, wherein an integer of 4 is assigned and set so as to satisfy the relationship of the following expressions (1) 'to (4).
TA ₁ <TA ₂ <TA ₃ <TA ₄ (1) '
TB ₁ <TB ₂ <TB ₃ <TB ₄ (2)
TC ₁ > TC ₂ > TC ₃ > TC ₄ (3)
TDn = TE− (TAn + TBn + TCn) (4) The water absorption temperature is Tn, and when the season for cooking rice is autumn, winter, spring, and summer, an integer of n = 1 to 4 is assigned in order, and the setting is made to satisfy the following relationship (5) The rice cooker of Claim 2 or 3 characterized by the above-mentioned.
T ₂ > T ₁ > T ₃ > T ₄ (5)

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