JP2018126267A - Pressure type rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure type rice cooker capable of adjusting pressure in a pot more accurately.SOLUTION: A pressure type rice cooker includes a heating device for heating a pot, a lid body for closing an opening of the pot, a pressure valve for opening/closing a steam discharge hole provided to the lid body, a pressure valve moving mechanism for adjusting pressure in the pot by moving the pressure valve between a closed position and an open position, a pressure detection part for detecting the pressure in the pot, and a control part for controlling the heating device and the pressure valve moving mechanism and executing a rice cooking process including a boiling maintaining process. The control part executes a pressure adjustment process in the boiling maintaining process, to cause the pressure valve moving mechanism to be operated at a first speed when a difference between a pressure value detected by the pressure detection part and a target pressure value is a threshold or more and to cause the pressure valve moving mechanism to be operated at a second speed slower than the first speed when a difference between the pressure value detected by the pressure detection part and the target pressure value is smaller than the threshold.SELECTED DRAWING: Figure 7

Description

  The present invention relates to a pressure rice cooker that cooks rice by pressurizing the pressure in the pan to atmospheric pressure or higher.

  Conventionally, as this type of pressure rice cooker, for example, pressure rice cookers described in Patent Documents 1 and 2 are known. Patent Document 1 discloses a pressure rice cooker including a pressure valve that opens and closes a steam discharge hole and a pressure valve moving mechanism that adjusts the pressure in the pan by moving the pressure valve. Patent Document 2 includes a pressure detection unit that detects the pressure in the pan, and is configured to switch on / off and a rotation direction of a stepping motor that moves the pressure valve according to a pressure value detected by the pressure detection unit. A pressure rice cooker is disclosed.

JP-A-2015-202304 JP 2004-57556 A

  However, in the pressure rice cooker of Patent Document 1, even if the pressure valve moving mechanism that moves the pressure valve is operated, the pressure in the pan does not immediately change (is not reflected), and some time lag occurs. Can do. For this reason, there is still room for improvement in terms of adjusting the pressure in the pan more accurately.

  Moreover, in the pressure-type rice cooker of patent document 2, when the pressure value which the pressure detection part detected is below a pressure lower limit value, a stepping motor is rotationally driven to a normal rotation direction, and a pressure valve is moved to the obstruction | occlusion direction. It is configured. Further, when the pressure value detected by the pressure detector is equal to or higher than the pressure upper limit value, the stepping motor is rotationally driven in the reverse direction, and the pressure valve is moved in the opening direction. Further, when the pressure value detected by the pressure detection unit is not less than the pressure lower limit value and not more than the pressure upper limit value, the stepping motor is turned off and the movement of the pressure valve is stopped.

  According to this configuration, for example, the pressure valve is closed, and the pressure valve is moved in the opening direction only when the pressure value detected by the pressure detector changes from the pressure lower limit value to the pressure upper limit value. Further, the pressure valve is opened, and the pressure valve is moved in the closing direction only when the pressure value detected by the pressure detector changes from the pressure upper limit value to the pressure lower limit value. For this reason, there exists a subject that the fluctuation | variation of a pressure is large and it is difficult to stabilize to target pressure. Therefore, also in the pressure type rice cooker of patent document 2, there is still room for improvement in terms of adjusting the pressure in the pan more accurately.

  Accordingly, an object of the present invention is to provide a pressure cooker capable of adjusting the pressure in the pan with higher accuracy in solving the above-described problems.

In order to achieve the above object, a pressure rice cooker according to the present invention comprises:
A heating device for heating the pan;
A lid that closes the opening of the pan;
A pressure valve that opens and closes a steam discharge hole that communicates the inside of the pan and the lid;
A pressure valve moving mechanism for adjusting the pressure in the pan by moving the pressure valve between a closed position for closing the steam discharge hole and an open position for opening the steam discharge hole;
A pressure detector for detecting the pressure in the pan;
A controller for controlling the heating device and the pressure valve moving mechanism to perform a rice cooking process including a boiling maintenance process;
A pressure rice cooker comprising:
The controller is
A target pressure value is set, and when the difference between the pressure value detected by the pressure detection unit and the target pressure value is greater than or equal to a threshold value in the boiling maintenance step, the pressure valve moving mechanism is operated at a first speed. On the other hand, when the difference between the pressure value detected by the pressure detection unit and the target pressure value is smaller than a threshold value, the pressure regulating step is to operate the pressure valve moving mechanism at a second speed slower than the first speed. I do.

  According to the pressure type rice cooker according to the present invention, the pressure in the pan can be adjusted more accurately.

It is a schematic cross section of the pressure type rice cooker which concerns on embodiment of this invention. It is sectional drawing shown with the perspective view of the pressure type rice cooker of FIG. It is a partially cutaway side view of the pressure type rice cooker of FIG. It is a top view which shows the state which removed the components by the side of the upper shell member of an outer cover from the pressure type rice cooker of FIG. It is a perspective view which decomposes | disassembles and shows some components of FIG. It is a graph which shows transition of the temperature in a pan, and a pressure when an example of a rice cooking process is performed using the pressure type rice cooker of FIG. It is a graph which shows the relationship between the pressure value which the pressure sensor unit detected in the pressure regulation process, and the operating speed of a pressure valve moving mechanism. It is a graph which shows transition of the temperature and pressure in a pan when the other example of a rice cooking process was performed using the pressure type rice cooker of FIG. It is a graph which shows the relationship between the pressure value which the pressure sensor unit detected when changing to a pressure regulation process from a temperature rising process, and the operating speed of a pressure valve moving mechanism. It is a graph which shows the relationship between the pressure value which the pressure sensor unit detected when changing to a pressure regulation process from a pressure reduction process, and the operating speed of a pressure valve moving mechanism.

According to a first aspect of the present invention, a pan,
A heating device for heating the pan;
A lid that closes the opening of the pan;
A pressure valve that opens and closes a steam discharge hole that communicates the inside of the pan and the lid;
A pressure valve moving mechanism for adjusting the pressure in the pan by moving the pressure valve between a closed position for closing the steam discharge hole and an open position for opening the steam discharge hole;
A pressure detector for detecting the pressure in the pan;
A controller for controlling the heating device and the pressure valve moving mechanism to perform a rice cooking process including a boiling maintenance process;
A pressure rice cooker comprising:
The controller is
A target pressure value is set, and when the difference between the pressure value detected by the pressure detection unit and the target pressure value is greater than or equal to a threshold value in the boiling maintenance step, the pressure valve moving mechanism is operated at a first speed. On the other hand, when the difference between the pressure value detected by the pressure detection unit and the target pressure value is smaller than a threshold value, the pressure regulating step is to operate the pressure valve moving mechanism at a second speed slower than the first speed. To provide a pressure rice cooker.

According to the second aspect of the present invention, the control unit includes:
A pressure upper limit value obtained by adding the threshold value to the target pressure value, and a pressure lower limit value obtained by subtracting the threshold value from the target pressure value;
In the pressure adjusting step,
When the pressure value detected by the pressure detector is equal to or lower than the pressure lower limit value, the pressure valve moving mechanism is operated at the first speed so that the pressure valve moves to the closed position,
When the pressure value detected by the pressure detector is between the target pressure value and the pressure lower limit value, the pressure valve moving mechanism is moved at the second speed so that the pressure valve moves to the closed position. Make it work,
When the pressure value detected by the pressure detector is between the target pressure value and the pressure upper limit value, the pressure valve moving mechanism is moved at the second speed so that the pressure valve moves to the open position. Make it work,
When the pressure value detected by the pressure detection unit is equal to or greater than the pressure upper limit value, the pressure valve moving mechanism is operated at the first speed so that the pressure valve moves to the open position;
The pressure type rice cooker as described in a 1st aspect is provided.

  According to the third aspect of the present invention, in the boiling maintaining step, the control unit includes a pressure increasing step for increasing the pressure value detected by the pressure detecting unit from a value lower than the pressure lower limit value to the target pressure value. The pressure type rice cooker according to the second aspect is provided, which shifts to the pressure adjusting step when the target pressure value is reached in the pressure increasing step.

  According to the fourth aspect of the present invention, in the boiling maintaining step, the control unit performs a step of decreasing the pressure value detected by the pressure detection unit from a value higher than the pressure upper limit value to the target pressure value. The pressure rice cooker according to the second or third aspect is provided, which performs and moves to the pressure regulating step when the target pressure value is reached in the step-down step.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In addition, this invention is not limited by this embodiment.

<Embodiment>
The pressure type rice cooker which concerns on embodiment of this invention is demonstrated. FIG. 1 is a schematic cross-sectional view of a pressure rice cooker according to an embodiment of the present invention. FIG. 2 is a perspective view of the pressure rice cooker of FIG.

  As shown in FIG. 1, the pressure rice cooker according to the present embodiment is stored in a substantially bottomed cylindrical rice cooker body 1 having a pot storage portion 1 a formed therein, and a pot storage portion 1 a. And a pan 2 into which an object to be cooked such as water is placed. A hollow outer cover 3 capable of opening and closing the upper opening of the rice cooker body 1 is attached to the upper portion of the rice cooker body 1. A substantially disk-shaped inner lid 4 capable of sealing the upper opening of the pan 2 is detachably attached to the inner side of the outer lid 3 (the side covering the upper opening of the pan 2). In the present embodiment, the outer lid 3 and the inner lid 4 constitute a lid that can open and close the upper opening of the pan 2.

  The pot storage part 1a of the rice cooker body 1 is composed of an upper frame 1b and a coil base 1c. The upper frame 1b has a cylindrical portion 1ba that is arranged so as to leave a predetermined gap with respect to the side wall of the stored pan 2, and an upper opening of the rice cooker body 1 that protrudes outward from the upper portion of the cylindrical portion 1ba. And a flange portion 1bb fitted to the inner peripheral portion. The upper end of the cylindrical portion 1ba supports a flange portion 2a provided around the upper opening of the pan 2.

  The coil base 1c is formed in a bottomed cylindrical shape corresponding to the shape of the lower portion of the pan 2, and the upper portion is attached to the lower end portion of the cylindrical portion 1ba of the upper frame 1b. A pan bottom heating unit 5, which is an example of a heating device for heating (induction heating) the pan 2, is attached to the outer peripheral surface of the coil base 1 c. The pan bottom heating unit 5 is composed of a bottom heating coil 5a and a bottom outside heating coil 5b. The in-bottom heating coil 5a is disposed so as to face the periphery of the center of the bottom of the pan 2 via the coil base 1c. Outer bottom heating coil 5b is arranged to face the corner portion of the bottom of pan 2 via coil base 1c.

  An opening is provided in the central portion of the bottom of the coil base 1c. In the opening, a pan temperature sensor 6, which is an example of a pan temperature detection unit for measuring the temperature of the pan 2, is disposed so as to be able to contact the bottom of the pan 2 stored in the pan storage unit 1 a. . Since the temperature of the pot 2 is substantially the same as the temperature of the cooking object in the pot 2, the pot temperature sensor 6 can detect the temperature of the cooking object in the pot 2 by detecting the temperature of the pot 2. it can.

  The outer lid 3 includes an upper outer member 3 a and a lower outer member 3 b that constitute the outer shell of the outer lid 3. The outer lid 3 includes a hinge shaft 3A. The hinge shaft 3A is an opening / closing shaft of the outer lid 3, and both ends of the hinge shaft 3A are rotatably fixed to the upper frame 1b of the rice cooker body 1. A torsion coil spring 7 is attached around the hinge shaft 3A. The torsion coil spring 7 elastically biases the outer lid 3 in a direction (opening direction) away from the upper opening of the pan 2 around the hinge shaft 3A.

  A lid opening device 8 is provided inside the outer lid 3. The lid opening device 8 is engaged with a part of the rice cooker main body 1 to maintain a state where the outer lid 3 blocks the upper opening of the pan 2. On the other hand, when the lid opening device 8 is pressed when the outer lid 3 closes the upper opening of the pan 2 and the open button 81 (see FIG. 2) provided on the rice cooker body 1 or the outer lid 3 is pressed, It rotates in the direction of arrow A1 about the hook shaft 8A. Thereby, the engagement between the lid opening device 8 and a part of the rice cooker body 1 is released, and the outer lid 3 is separated from the upper opening of the pan 2 around the hinge shaft 3 </ b> A by the biasing force of the torsion coil spring 7. Rotate to. Thereby, the outer lid 3 is in an open state that does not block the upper opening of the pan 2. For example, the outer lid 3 is configured to stop the rotation when rotated 90 degrees around the hinge shaft 3A from the position where the upper opening of the pan 2 is closed.

  A recess 3d is provided in the vicinity of the hinge shaft 3A of the upper outer member 3a. A steam cylinder 9 is detachably attached to the recess 3d. A steam escape hole 3da is provided at the bottom of the recess 3d so that excess steam in the pan 2 can be discharged toward the steam cylinder 9. A steam escape hole 9a is provided on the upper wall of the steam cylinder 9 so that excess steam in the pot 2 can be discharged to the outside of the rice cooker.

  The inner lid 4 is provided with a steam discharge hole 4a for discharging the steam in the pan 2 and a steam discharge hole 4b for communicating the inside of the pan 2 and the lid body. The diameter of the steam discharge hole 4b is larger than the diameter of the steam discharge hole 4a, and is set to be twice or more the diameter of the steam discharge hole 4a, for example. The diameter of the steam discharge hole 4a is, for example, 4 mm, and the diameter of the steam discharge hole 4b is, for example, 10 mm.

  The inner lid 4 is provided with a pressure suppression valve 10 capable of opening and closing the steam discharge hole 4a and a pressure valve 11 capable of opening and closing the steam discharge hole 4b.

  The pressure suppression valve 10 is a valve that suppresses the pressure in the pan 2 from rising to a predetermined value (eg, 1.2 atmospheres) higher than the atmospheric pressure. In this Embodiment, the pressure suppression valve 10 is comprised with the ball | bowl, and obstruct | occludes the steam discharge hole 4a with dead weight. On the other hand, the pressure suppression valve 10 is pushed only by the pressure in the pan 2 when the pressure in the pan 2 becomes larger than its own weight (for example, when the pressure becomes 1.2 atm or more), and the pressure suppression valve 10 is pushed from the steam discharge hole 4a. The steam exhaust hole 4a is opened.

  The pressure valve 11 is configured to move between a closed position for closing the steam discharge hole 4b and an open position for opening the steam discharge hole 4b.

  The outer lid 3 is provided with a pressure valve moving mechanism 12 that moves the pressure valve 11 between a closed position and an open position so as to open and close the steam discharge hole 4b. The pressure valve moving mechanism 12 is configured to press the pressure valve 11 with a pressure larger than a predetermined value (for example, 1.2 atmospheres) and hold the pressure valve 11 in the closed position. Thereby, the pressure in the pan 2 can be increased (for example, increased from 1.0 atm to 1.2 atm). Further, the pressure valve moving mechanism 12 moves the pressure valve 11 from the closed position under the control of the control unit 14 described later at a predetermined timing when the pressure in the pan 2 becomes a predetermined value (for example, 1.2 atmospheres) or more. It is configured to move to the open position. Thereby, the pressure in the pan 2 can be reduced (for example, reduced from 1.2 atm to 1.0 atm). Note that the specific configuration of the pressure valve moving mechanism 12 is the same as that of a conventional pressure valve moving mechanism (see, for example, Patent Document 1), and thus the description thereof is omitted here.

  In addition, various information such as rice cooking course and rice cooking time are displayed on the outer lid 3, and a specific rice cooking course can be selected from a plurality of rice cooking courses such as a white rice course, a brown rice course, and a white rice (softer) course. A display operation unit 13 is provided. The display operation unit 13 includes a liquid crystal display 13A for displaying various information such as a rice cooking course and a rice cooking time, and a plurality of buttons 13B for instructing execution of rice cooking start, cancellation, reservation and the like in addition to the selection of the rice cooking course. ing. The user can instruct the start of cooking by selecting a specific rice cooking course with the plurality of buttons 13B while referring to various types of information displayed on the liquid crystal display 13A.

  A control unit 14 is mounted inside the rice cooker body 1. The control unit 14 includes a storage unit that stores a plurality of rice cooking sequences for cooking rice. Here, in the “rice cooking sequence”, when the four steps of preheating, temperature rising, boiling maintenance, and steaming are performed in order, the energization time, heating temperature, heating time, heating output, etc. are determined in advance in each step. This is the cooking procedure. Each rice cooking sequence corresponds to one of a plurality of rice cooking courses. The control unit 14 controls the pot bottom heating unit 5 and the pressure valve moving mechanism 12 based on the rice cooking course selected by the display operation unit 13 and the detected temperature of the pot temperature sensor 6, and executes the rice cooking process.

  FIG. 3 is a partially cutaway side view of the pressure rice cooker of FIG. FIG. 4 is a plan view showing a state in which components on the upper outer member 3a side of the outer lid 3 are removed from the pressure rice cooker of FIG. FIG. 5 is an exploded perspective view showing some components of FIG.

  As shown in FIGS. 3 to 5, the outer lid 3 includes a pressure sensor unit 21 that is an example of a pressure detection unit that detects the pressure in the pan 2. More specifically, the pressure sensor unit 21 is attached to the lower outline member 3 b of the outer lid 3.

  As shown in FIG. 3, the lower outer member 3 b of the outer lid 3 is provided with a through hole 3 c at the attachment position of the pressure sensor unit 21. The inner lid 4 is provided with a through hole 4 c at a position facing the through hole 3 c when the inner lid 4 is attached to the lower outer member 3 b of the outer lid 3. The pressure sensor unit 21 communicates with the inside of the pan 2 through the through hole 4c and the through hole 3c, and detects the pressure in the pan 2.

  Next, the operation of the pressure rice cooker according to this embodiment will be described. FIG. 6 is a graph showing changes in temperature and pressure in the pan 2 when an example of the rice cooking process is performed using the pressure rice cooker according to the present embodiment.

  First, the pot 2 in which the cooking object containing the rice and water which are to-be-cooked objects was put by the user is set to the pan accommodating part 1a. Then, after the rice cooking course is selected by the display operation unit 13 and then the start of rice cooking is instructed by the user, the rice cooking process is started under the control of the control unit 14. When the rice cooking process is started, first, the preheating process is started.

  The preheating step is a step of immersing the rice in water at a temperature lower than the gelatinization temperature so that the rice can be sufficiently gelatinized in the subsequent steps, and allowing the rice to absorb water in advance. In this preheating step, the controller 14 raises the temperature of the water in the pot 2 to a temperature close to the temperature at which rice gelatinization begins (about 50 ° C.), and then maintains the temperature after the temperature rise. The pot heating operation of the pot bottom heating unit 5 is controlled based on the temperature detected by the pot temperature sensor 6. Further, the control unit 14 controls the pressure valve moving mechanism 12 so that the pressure valve 11 is held at the closed position during the preheating process. When a preset time has elapsed from the start of the preheating process according to the selected rice cooking course, the process proceeds to the temperature raising process.

  The temperature raising process is a process in which the pot 2 is heated at a stretch with a strong fire to bring the water in the pot 2 to a boiling state. In this temperature raising step, the control unit 14 controls the pan bottom heating unit 5 so as to rapidly heat the pan 2 and bring the water in the pan 2 to a boiling state. Further, the control unit 14 controls the pressure valve moving mechanism 12 so that the pressure valve 11 is held at the closed position during the temperature raising process. When the temperature detected by the pan temperature sensor 6 reaches the boiling point of the water in the pan 2 (about 100 ° C.), the process proceeds to the boiling maintaining step.

  A boiling maintenance process is a process of maintaining the boiling state of the water in the pan 2, gelatinizing rice starch, and raising the gelatinization degree to about 50% to 80%. In this boiling maintenance step, the control unit 14 controls the pan bottom heating unit 5 and the pressure valve moving mechanism 12 so as to maintain the boiling state of the water in the pan 2.

  In the initial stage of the boiling maintenance process, the control unit 14 performs a pressure increasing process for increasing the pressure in the pan 2 (for example, increasing from 0 kPa to 20 kPa) by continuously holding the pressure valve 11 at the closed position by the pressure valve moving mechanism 12. Do. By this pressurization step, the boiling point of water in the pan 2 increases (for example, about 105 ° C.).

  Then, the control part 14 controls the pressure valve moving mechanism 12, and performs the pressure regulation process which adjusts the pressure in the pan 2 to target pressure. In this pressure adjusting process, the control unit 14 sets a target pressure value, and the pressure valve moving mechanism 12 is based on whether or not the difference between the pressure value detected by the pressure sensor unit 21 and the target pressure value is smaller than a threshold value. Change the operating speed.

  FIG. 7 is a graph showing the relationship between the pressure value detected by the pressure sensor unit 21 in the pressure adjusting process and the operating speed of the pressure valve moving mechanism 12. In the present embodiment, a value obtained by adding a threshold value (for example, 1 kPa) to the target pressure value PTEP is set as a pressure upper limit value PMAX, and a value obtained by subtracting the threshold value (for example, 1 kPa) from the target pressure value PTEP is set as a pressure lower limit value PMIN. . In the present embodiment, the control unit 14 sets the pressure upper limit value PMAX and the pressure lower limit value PMIN together with the target pressure value PTEP.

  As shown in FIG. 7, in the pressure adjusting process, the control unit 14 moves the pressure valve so that the pressure valve 11 moves to the closed position when the pressure value detected by the pressure sensor unit 21 is equal to or lower than the pressure lower limit value PMIN. The mechanism 12 is operated at a high speed which is the first speed. Further, the control unit 14 controls the pressure valve moving mechanism 12 so that the pressure valve 11 moves to the closed position when the pressure value detected by the pressure sensor unit 21 is between the target pressure value PTEP and the pressure lower limit value PMIN. The operation is performed at a low speed that is a second speed slower than the first speed. Further, the control unit 14 controls the pressure valve moving mechanism 12 so that the pressure valve 11 moves to the open position when the pressure value detected by the pressure sensor unit 21 is between the target pressure value PTEP and the pressure upper limit value PMAX. Operate at low speed. Furthermore, when the pressure value detected by the pressure sensor unit 21 is equal to or higher than the pressure upper limit value PMAX, the control unit 14 operates the pressure valve moving mechanism 12 at a high speed so that the pressure valve 11 moves to the open position. As described above, the control unit 14 controls the operation of the pressure valve moving mechanism 12 so that the pressure value detected by the pressure sensor unit 21 converges so as to be closer to the target pressure value PTEP. Thereby, the pressure in the pan 2 can be adjusted more accurately.

  In the boiling maintenance step, a large amount of steam is generated because water is continuously boiled. This steam passes through the steam discharge hole 4a, the steam discharge hole 4b, the steam escape holes 3da, 9a, etc., and is discharged to the outside of the rice cooker. Thereby, when most of the water in the pot 2 runs out, the temperature of the bottom surface of the pot 2 rises above the boiling point of water. When the temperature detected by the pan temperature sensor 6 reaches a predetermined temperature not lower than the boiling point (for example, 130 ° C.), the steaming process is started.

  The steaming process is a process of evaporating excess water using preheating and raising the degree of gelatinization of rice to nearly 100%. During this steaming process, the control unit 14 controls the pressure valve moving mechanism 12 so as to move the pressure valve 11 from the closed position to the open position. Thereby, the inside of the pan 2 is depressurized to substantially atmospheric pressure. When a preset time has elapsed from the start of the steaming process, the steaming process is terminated (that is, the rice cooking process is terminated).

  According to the pressure rice cooker according to the present embodiment, the control unit 14 is based on whether or not the difference between the pressure value detected by the pressure sensor unit 21 and the target pressure value PTEP is smaller than a threshold value. A pressure adjusting process for changing the operation speed of 12 is performed. Thereby, even if there is a time lag between the operation of the pressure valve moving mechanism 12 for moving the pressure valve 11 and the change in the pressure in the pan 2, the pressure in the pan 2 is converged so as to approach the target pressure value PTEP sooner. be able to. Therefore, the pressure in the pan 2 can be adjusted with higher accuracy.

  In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. For example, in the above description, the control unit 14 performs the pressure adjusting process after the pressure increasing process until the boiling maintaining process ends, but the present invention is not limited to this. In the boiling maintenance process, the longer the time for maintaining the inside of the pan 2 at a high pressure, the greater the amount of heating that each rice grain receives, and the sweetness of the rice can be increased, while the stickiness of the rice increases excessively. There is a risk of stickiness. Therefore, as shown in FIG. 8, the control unit 14 reduces the target pressure value PTEP (for example, 10 kPa) during the pressure adjustment process, and holds the pressure valve 11 in the open position by the pressure valve moving mechanism 12. You may perform the pressure reduction process which drops the pressure in the pan 2 by continuing. Thereby, while increasing the sweetness of rice, the excessive stickiness of rice can be suppressed and a taste can be improved.

  As shown in FIG. 9, the control unit 14 becomes the target pressure value PTEP in the pressure increasing process for increasing the pressure value detected by the pressure sensor unit 21 from a value lower than the pressure lower limit value PMIN to the target pressure value PTEP. It is preferable to control so as to shift to the pressure adjusting step. Thereby, it can suppress that the pressure value which the pressure sensor unit 21 detects exceeds pressure upper limit PMAX, and can converge the pressure in the pan 2 so that it may approach target pressure value PTEP earlier. . Therefore, the pressure in the pan 2 can be adjusted with higher accuracy.

  Further, as shown in FIG. 10, the control unit 14 becomes the target pressure value PTEP in the step-down process of lowering the pressure value detected by the pressure sensor unit 21 from a value higher than the pressure upper limit value PMAX to the target pressure value PTEP. It is preferable to control so as to shift to the pressure adjusting process. Thereby, it can suppress that the pressure value which the pressure sensor unit 21 detects exceeds the pressure lower limit PMIN, and it can be made to converge so that the pressure in the pan 2 may approach the target pressure value PTEP earlier. . Therefore, the pressure in the pan 2 can be adjusted with higher accuracy.

  In the above description, the control unit 14 performs at least one of the pressure increasing process, the pressure adjusting process, and the pressure decreasing process in the boiling maintaining process, but the present invention is not limited to this. For example, you may make it the control part 14 perform a pressure | voltage rise process, a pressure regulation process, or a pressure | voltage fall process in other rice cooking processes, such as a steaming process.

  While the invention has been fully described in connection with preferred embodiments with reference to the accompanying drawings, various changes and modifications will be apparent to those skilled in the art. Such changes and modifications are to be understood as being included therein, so long as they do not depart from the scope of the present invention according to the appended claims.

  Since the pressure type rice cooker according to the present invention can adjust the pressure in the pan more accurately, for example, household and commercial pressure type rice cookers that are required to cook rice with less uneven cooking. Useful for.

DESCRIPTION OF SYMBOLS 1 Rice cooker main body 1A Hinge part 1a Pan storage part 1b Upper frame 1ba Tubular part 1bb Flange part 1c Coil base 2 Pan 2a Flange part 3 Outer lid 3A Hinge shaft 3a Upper outer member 3b Lower outer member 3c Through hole 3d Recessed part 3da Steam Relief hole 4 Inner lid 4a, 4b Steam discharge hole 4c Through hole 5 Pan bottom heating unit (heating device)
5a Heating coil in the bottom 5b Heating coil outside the bottom 6 Pan temperature sensor 7 Torsion coil spring 8 Lid opening device 8A Hook shaft 9 Steam tube 9a Steam escape hole 10 Pressure suppression valve 11 Pressure valve 12 Pressure valve moving mechanism 13 Display operation part 13A Liquid crystal Display 13B Button 14 Control unit 21 Pressure sensor unit (pressure detection unit)
81 Open button

Claims (4)

With a pot,
A heating device for heating the pan;
A lid that closes the opening of the pan;
A pressure valve that opens and closes a steam discharge hole that communicates the inside of the pan and the lid;
A pressure valve moving mechanism for adjusting the pressure in the pan by moving the pressure valve between a closed position for closing the steam discharge hole and an open position for opening the steam discharge hole;
A pressure detector for detecting the pressure in the pan;
A controller for controlling the heating device and the pressure valve moving mechanism to perform a rice cooking process including a boiling maintenance process;
A pressure rice cooker comprising:
The controller is
A target pressure value is set, and when the difference between the pressure value detected by the pressure detection unit and the target pressure value is greater than or equal to a threshold value in the boiling maintenance step, the pressure valve moving mechanism is operated at a first speed. On the other hand, when the difference between the pressure value detected by the pressure detection unit and the target pressure value is smaller than a threshold value, the pressure regulating step is to operate the pressure valve moving mechanism at a second speed slower than the first speed. Do the pressure rice cooker. The controller is
A pressure upper limit value obtained by adding the threshold value to the target pressure value, and a pressure lower limit value obtained by subtracting the threshold value from the target pressure value;
In the pressure adjusting step,
When the pressure value detected by the pressure detector is equal to or lower than the pressure lower limit value, the pressure valve moving mechanism is operated at the first speed so that the pressure valve moves to the closed position,
When the pressure value detected by the pressure detector is between the target pressure value and the pressure lower limit value, the pressure valve moving mechanism is moved at the second speed so that the pressure valve moves to the closed position. Make it work,
When the pressure value detected by the pressure detector is between the target pressure value and the pressure upper limit value, the pressure valve moving mechanism is moved at the second speed so that the pressure valve moves to the open position. Make it work,
When the pressure value detected by the pressure detection unit is equal to or greater than the pressure upper limit value, the pressure valve moving mechanism is operated at the first speed so that the pressure valve moves to the open position;
The pressure type rice cooker according to claim 1.   The controller performs a boosting step of increasing the pressure value detected by the pressure detection unit from a value lower than the pressure lower limit value to the target pressure value in the boiling maintenance step, and the target pressure value in the boosting step The pressure type rice cooker according to claim 2, wherein the pressure type rice cooker shifts to the pressure adjusting step.   The control unit performs a step of decreasing the pressure value detected by the pressure detection unit from a value higher than the pressure upper limit value to the target pressure value in the boiling maintaining step, and the target pressure value in the step of decreasing pressure The pressure-type rice cooker according to claim 2 or 3, wherein the process proceeds to the pressure regulating step.