JP5037394B2 - Pressure cooker - Google Patents

Description

  The present invention relates to a pressure cooker.

  A rice cooker, which is one of the cookers, includes a main body that houses an inner pot and a lid that is attached to the main body so as to be openable and closable, and heats the inner pot by heating means disposed inside the main body. This is what cooks the rice set in the inner pot. In addition, as this type of rice cooker, there is a pressure rice cooker in which a sealing means for closing the vent hole of the exhaust passage is provided in the lid body, and the inside of the inner pot can be boosted to a pressure higher than atmospheric pressure. is there.

  This pressure rice cooker is in a state where the internal pressure of the inner pot is higher than the atmospheric pressure immediately after the completion of rice cooking, immediately after the user stops cooking rice, or immediately after the rice cooking is terminated (interrupted) due to a power failure. Sometimes. And if a user opens a cover body in this state, a cover body may open vigorously or a vapor | steam may spout.

  Therefore, a rice cooker is provided with a display means such as an LED on the lid opening button for opening the lid so that the user can know whether the lid may be opened or not open. Is provided. In this rice cooker, the lid cannot be opened unless the cutting means (switch) of the operation panel is operated. Further, when the pressure release means is operated, the lid cannot be opened until the pressure returns to near normal pressure (see Patent Document 1).

  Alternatively, a segment for displaying the word “pressure” is provided on the liquid crystal display panel. When the inner pot is higher than the set pressure (1.05 atm), the pressure segment is turned on. Turn off the light. Also, if a power outage occurs during cooking, if the inside pan is pressurized immediately before the power outage, the pressure segment will blink until the waiting time for the inside pan to drop below the set pressure has elapsed. A pressure rice cooker is provided in which the pressure segment is turned off when the standby time elapses (see Patent Document 2).

JP 2007-252620 A Published technical report 2008-501203

  However, the time required for the pressure drop in the inner pot differs depending on the maximum pressure that can be pressurized by the pressurizing means and the actual pressure when the rice cooking is stopped, but in these patent documents, a preset waiting time is set. It is necessary to wait until (1 minute) has elapsed. Therefore, it is almost possible to ensure safety, but it also has an inconvenience because it includes unnecessary waiting time.

  This invention is made | formed in view of the conventional problem, and makes it a subject to provide the pressure cooker which can notify a user quickly that the inside of a pan fell to the safe pressure.

In order to solve the above-mentioned problems, a pressure cooker according to the present invention includes a main body having a pan that accommodates an object to be heated, a heating unit that is disposed in the main body and heats the pan, and a lid that closes the pan. A body, an exhaust passage provided in the lid for communicating the inside of the pan with the outside, a lid provided on the lid for closing the exhaust passage so that the inside of the pan can be pressurized, and the exhaust A pressure cooker comprising: a pressure input unit that opens a passage to balance the pressure in the pan with an external pressure; and a control unit that performs cooking by controlling the heating unit and the pressure input unit according to a preset program. The following configuration is used.
In the first pressure cooker, a pressure detection means for detecting the pressure in the pan is provided, a pressure display section for displaying the pressure state in the pan based on the detected pressure by the pressure detection means, and A backup power source for operating the control means and the pressure display unit at the time of a power failure is provided, and the control means recognizes whether the operation is based on the commercial power source or the backup power source based on the input voltage, and enters the pot by the pressure input unit due to the power failure. When the pressure input is released, the inside of the pan is set in advance based on the pressure detected by the pressure detecting means at the time of releasing the pressure input and the preset pressure drop gradient or the data table. A time for dropping below the reference pressure is set, and the display state of the pressure display unit is changed after the set time elapses.
In the second pressure cooker, temperature detection means for detecting the temperature of the pot or the pot is provided, and the temperature in the pot is determined based on the estimated pressure in the pot corresponding to the temperature detected by the temperature detection means. A pressure display unit that displays a pressure state is provided, and a backup power source that operates the control unit and the pressure display unit in the event of a power failure is provided. The control unit determines whether the operation is performed by a commercial power source or a backup power source depending on an input voltage. Recognizing, when the pressure input into the pan by the pressure input means is canceled due to a power failure, the temperature detected by the temperature detection means at the time of pressure input release and the preset temperature decrease gradient or Based on the data table, a time for the inside of the pan to fall below a preset reference temperature is set, and after the set time has elapsed, the pressure It is configured to change the display state of the display unit.
Further, the third pressure cooker is provided with temperature detection means for detecting the temperature of the pot or the pot, and based on the estimated pressure in the pot corresponding to the temperature detected by the temperature detection means. A pressure display unit that displays a pressure state is provided, and a backup power source that operates the control unit and the pressure display unit in the event of a power failure is provided. The control unit determines whether the operation is performed by a commercial power source or a backup power source depending on an input voltage. Recognizing and canceling the pressure input into the pan by the pressure input means due to a power outage, the estimated pressure corresponding to the temperature detected by the temperature detection means at the time of pressure input release with the power from the backup power supply, and preset Set the time for the inside of the pan to drop below the preset reference pressure based on the pressure drop gradient or data table After the elapse has a configuration to change the display state of the pressure display unit.
In these pressure cookers, “ at the time of releasing pressure ” is a range including immediately before and after the release of pressure (± about 1 second). The “estimated pressure in the pan corresponding to the detected temperature” is based on conversion based on the correlation between temperature and pressure.

  According to these pressure rice cookers, based on a pre-set pressure or temperature descent gradient, or a data table, a reference pressure that can ensure safety, or a time for dropping below a temperature corresponding to the reference pressure. Since it is set and the display state of the pressure display unit is changed after the set time has elapsed, it is possible to notify the user that the pressure has dropped to a safe pressure quickly without including unnecessary standby time.

  In these pressure rice cookers, the control means determines the capacity of the object to be heated based on the temperature increase gradient detected during heating by the heating means, and the downward gradient or the data table is changed depending on the determined capacity. It is preferable to do. In this way, unnecessary waiting time can be eliminated.

  In the pressure cooker of the present invention, the setting for changing the display state of the pressure display unit based on the detected pressure or detected temperature when the pressure input is released, the preset pressure or temperature descending gradient, or the data table Because the time is set, the user can be informed quickly that the pressure has dropped to a safe pressure without including unnecessary waiting time.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a pressure cooker that is a cooker according to an embodiment of the present invention. This pressure rice cooker includes an inner pot 10, a main body 11 that detachably accommodates the inner pot 10, and a lid body 17 that is attached to the main body 11 so as to be opened and closed.

  The inner pot 10 accommodates rice to be heated together with water, and energizes a high-frequency current to the induction heating coil 14 described later on the outer surface of a pot base material made of aluminum or the like having high thermal conductivity. Ferromagnetic materials that are heated by electromagnetic induction by eddy currents that are sometimes generated are applied by coating or bonding.

  The main body 11 includes a protective frame 13 made of a non-conductive material that accommodates the inner pot 10 inside an exterior body 12 having a bottomed cylindrical shape. The protective frame 13 is provided with an induction heating coil 14 that is a first heating means wound around the bottom, and a body heater 15 that is a second heating means is provided on the outer peripheral wall. The protective frame 13 is provided with an inner pot temperature sensor 16 that is a temperature detecting means for detecting the temperature of the inner pot 10 through the protective frame 13.

  The lid body 17 covers the opening of the main body 11 and closes (closes) the opening of the inner pot 10, and a heat radiating plate 18, a lid heater 19 and an inner lid 20 are disposed on the inner pot 10 side. ing. The lid 17 is provided with an exhaust passage 21 that communicates the inside of the inner pot 10 with the outside, and a relief valve 22 that is a pressure input means is interposed in the exhaust passage 21. In this relief valve 22, an inner sphere 23 is rolled by a solenoid 24. Specifically, when the solenoid 24 is energized, the rod moves backward, and the exhaust passage 21 is closed by the sphere 23 so that the inner pot 10 can be pressurized to a pressure higher than the atmospheric pressure. Further, when the energization to the solenoid 24 is cut off, the rod advances, and the internal pressure of the inner pot 10 is returned to the atmospheric pressure (equilibrium) by releasing (opening) the block of the exhaust passage 21 by the sphere 23. . Further, inside the lid body 17, a lid temperature sensor 25 which is a temperature detection means for detecting the temperature in the inner pot 10, and a pressure sensor which is a pressure detection means for detecting the pressure in the inner pot 10. 26 is arranged.

  And in the pressure rice cooker of this embodiment, the operation panel 27 shown in FIG. The operation panel 27 includes a liquid crystal display panel 28 as display means at the center. A numerical segment 29 indicating the reservation time, the remaining time required for cooking rice, and the like is provided in the middle stage of the liquid crystal display panel 28. The upper portion of the numerical segment 29 is provided with a non-washed rice segment 30 that indicates whether or not the washing-free rice is selected, and the display of the numerical segment 29 beside the remaining time (minutes) required for cooking rice. ), A segment 31 is provided. In addition, a reservation segment 32 is provided at the bottom of the numerical value segment 29. The reservation segments 32 indicate the two types of reserved rice cooking with the letters “reserve”, “1”, and “2” and numbers. Further, a pressure segment 33 that is a pressure display portion that indicates in a letter a pressure state that the inside of the inner pot 10 is pressurized and the internal pressure is higher than a preset reference pressure is provided next to the reserved segment 32. Further, a minute segment 34 is provided beside the pressure segment 33 and indicates the unit of time required for the rice cooking for the numerical value segment 29 to be displayed. A plurality of mark segments 35 having a triangular shape are provided around the liquid crystal display panel 28 to indicate the selection state of the rice cooking menu.

  In addition, the operation panel 27 has a plurality of rice cooking menus such as “normal”, “mochimochi”, “shakuri” of white rice, and others, so as to be positioned next to the mark segment 35 around the liquid crystal display panel 28. Character display 36 of “Aged Cooking”, “Rapid Rice Rapid”, “Cooked Rice”, “Sushimeshi”, “Okayu”, “Okowa”, “Brown Rice”, “Brown Rice Activity” is provided. Further, in order to display the selection state of the two types of heat insulation temperatures, a heat insulation display portion 37 indicated by the characters “standard” and “high” is provided on the lower side portion of the liquid crystal display panel 28 and corresponds to each. LED 38 is provided.

  Further, the operation panel 27 includes a plurality of switches 39a to 39h as input means. On the right side of the liquid crystal display board, a rice cooking switch 39a that is an execution switch for rice cooking processing, a reservation switch 39b that is a selection switch for reserved rice cooking, an up switch 39c and a down switch 39d for changing the current time, rice cooking time, etc. And are provided. In addition, on the left side of the liquid crystal display panel 28, there is a barge switch 39e for canceling (stopping) rice cooking and heat-retaining processing and a selection state, a menu switch 39f for selecting a rice cooking menu, and whether or not the rice is washed. A non-washing rice switch 39g for selecting the temperature, and a heat retention selection switch 39h for selecting a heat retention process mode as well as a heat retention process execution switch.

  In the pressure rice cooker configured in this way, a control board (not shown) is disposed between the exterior body 12 and the protective frame 13, and preset by a microcomputer 40 which is a control means mounted on the control board. Cooking rice and heat retention are executed according to the program.

  Specifically, the microcomputer 40 includes a voltage determination unit 40a at the power supply port. A commercial power supply 41 is connected to the power supply line connected to the power supply port via a power cord and a power circuit (not shown), and a primary battery 42 as a backup power supply is connected. The commercial power supply 41 outputs 5V drive power to the microcomputer 40 via the power supply circuit, the induction heating coil 14, the heaters 15 and 19, the solenoid 24 which is a drive means for the pressure input means, and the detection. Drive power is supplied to the sensors 16, 25, 26, and the like. The primary battery 42 supplies driving power of 3V to the microcomputer 40 when the power from the commercial power supply 41 is cut off. The microcomputer 40 can recognize whether the driving power is 5V or 3V by the voltage determination unit 40a, so that the operation is based on the power from the commercial power source 41 or the power from the primary battery 42.

  The microcomputer 40 is connected to a ROM 43 that is a nonvolatile storage means. This ROM 43 is capable of retaining stored information even if the power from the commercial power source 41, the primary battery 42, etc. is cut off (is not lost), and is used in a plurality of execution programs including the rice cooking and heat retention processes, and each execution program. Setting data (data table) and arithmetic expressions to be stored are stored. The execution program is roughly divided into a program executed in the power supply state (normal mode) from the commercial power supply 41 and a program executed in the power supply state (backup mode) from the primary battery 42. In the normal mode, the execution program of the original pressure rice cooker such as the rice cooking and the heat retaining process is executed. In the backup mode, only the voltage discriminating unit 40a, the timer 40b which is a time measuring unit for measuring time (time), and the minimum backup program for displaying the liquid crystal display panel 28 are executed.

  Further, the microcomputer 40 is connected with a RAM 44 which is a volatile storage means. This RAM 44 loses the stored information when the power from the commercial power source 41, the primary battery 42, etc. is cut off. The selected state for executing the rice cooking process by the user, and information during the execution of the rice cooking and heat retaining processes. Is temporarily stored.

  Furthermore, a liquid crystal display panel 28 is connected to the microcomputer 40 via a liquid crystal driving unit 45. The liquid crystal drive unit 45 is a well-known unit that turns on, blinks, and turns off a predetermined segment constituting the liquid crystal display panel 28.

  And if the microcomputer 40 of this embodiment detects operation of the rice cooking switch 39a in a normal mode, based on the rice cooking conditions set by the liquid crystal display board 28, according to the rice cooking program memorize | stored in ROM43, preheating, medium-puff, The rice cooking process which consists of each process of boiling maintenance including boiling maintenance and cooking twice is performed. Then, the heat retention process which heats the cooked rice at a predetermined temperature is subsequently performed. In the rice cooking process, the rice cooking capacity at that time is determined based on the rising gradient of the temperature detected by the temperature sensor 16 for the inner pot in the middle-puff process. Furthermore, at the same time as starting the middle-pump process or when the temperature in the inner pot 10 rises to a predetermined temperature in the middle-patch process, energization of the solenoid 24 is started, and in the subsequent boiling maintenance process, The pressure is increased to a pressure higher than atmospheric pressure. In the unevenness process, the energization of the solenoid 24 is interrupted, and the pressure input to the inner pot 10 is released.

  In the state where the pressure is put into the inner pot 10, the pressure in the inner pot 10 is detected by the pressure sensor 26 every predetermined time (1 second) and is equal to or higher than the reference (safety) pressure stored in the ROM 43 (5 kPa (1 .05 atm)), the pressure segment 33 of the liquid crystal display panel 28 is turned on. When the pressure is released, the pressure in the inner pot 10 is detected by the pressure sensor 26, and when the pressure falls below the reference pressure, the pressure segment 33 is turned off.

  On the other hand, in the backup mode, the elapsed time is measured by the timer 40 b and the current time is displayed on the liquid crystal display panel 28. In addition, during the execution of the rice cooking process in the normal mode, when the power from the commercial power supply 41 is cut off and the mode is changed to the backup mode, the rice cooking process is interrupted. And if this power failure time is measured and electric power returns in less than 10 minutes, a rice cooking process will be performed continuously, but if 10 minutes or more pass, a rice cooking process will be stopped even if electric power returns. In this backup mode, the display process of the pressure segment 33 is executed in parallel with the time measurement process.

  The display process in the backup mode is executed when the pressure segment 33 is displayed before the power failure, that is, when the pressure in the inner pot 10 is higher than the reference pressure. In this display process, the inner pot 10 is detected by the pressure detected by the pressure sensor 26 immediately before the power failure, that is, the detected pressure immediately before the pressure input is canceled due to the power failure, and the calculation formula based on the preset pressure decrease gradient. Estimate and set the time for the inside to drop below the reference pressure. Then, the pressure segment 33 is blinked until the set time elapses, and is extinguished after the elapse of time. In the present embodiment, in the boiling maintaining process of the rice cooking process, the pressure sensor 26 detects the internal pressure of the inner pot 10 every second, so the immediately preceding detected pressure is within one second.

  Here, FIG. 3 shows a pressure drop gradient when the relief valve 22 is opened with the maximum pressure (1.3 atm) that can be pressurized in the inner pot 10. As shown in FIG. 3, the pressure decreasing gradient in the inner pot 10 differs depending on the rice cooking capacity. When the rice cooking capacity is large, the descending gradient becomes gentle, and as the rice cooking capacity decreases, the descending gradient becomes steeper.

  Therefore, in this embodiment, it comprises so that the computing equation for calculating setting time may be changed with the discriminating rice cooking capacity. In the following, formulas for 10.0 cup, 5.5 cup, 1.0 cup, and 0.5 cup are shown.

[Equation 1]
10.0 cup y = 0.005x + 1
5.5 cup y = 0.010x + 1
1.0 cup y = 0.020x + 1
0.5cup y = 0.040x + 1

  This arithmetic expression is the time (x) until the pressure (y) when the pressure is released is balanced (decreased) to atmospheric pressure. For example, the safe reference pressure is (1.05 atm) higher than the atmospheric pressure (1.00 atm). For this reason, safety can be sufficiently ensured even if the time required for the pressure to drop to atmospheric pressure is set, but the safety of the user can be surely ensured by setting including some errors. Needless to say, the above-described arithmetic expression differs depending on factors such as the structure of the exhaust passage 21.

  Next, the control by the microcomputer 40 will be specifically described.

  First, in a state where the user has purchased a pressure rice cooker, the microcomputer 40 is operating in the backup mode with power from the primary battery 42.

  In this state, as shown in FIG. 4, the microcomputer 40 first detects whether or not it is connected to a commercial power source in step S <b> 1 using the voltage determination unit 40 a. If the connection to the commercial power source 41 is not detected, the process proceeds to step S2, a power failure process (backup mode) described in detail later is executed, and the process returns to step S1. When connection to the commercial power source 41 is detected, the process proceeds to step S3.

  In step S3, a power failure recovery process based on the state before the power failure and the state at the time of power failure recovery is executed, and the process proceeds to step S4. Specifically, in this power failure recovery process, if the state before the power failure was during the rice cooking process and the power failure time was less than 10 minutes, continue the rice cooking process from the state before the power failure. Run. Moreover, in the state other than that before a power failure, it is set as the standby state (state of step S4) which is not performing both the rice cooking process including reservation rice cooking, and a heat retention process.

  In step S4, it is detected whether any of the switches 39a to 39h is operated. When the operation of any of the switches 39a to 39h is detected, the process proceeds to step S5, the switch reception process corresponding to the detected switches 39a to 39h is executed, and the process returns to step S1. If no operation of any of the switches 39a to 39h is detected, the process directly returns to step S1.

  And when operation of the rice cooking switch 39a is detected, the rice cooking process shown in FIG. 5 is performed. The reserved rice cooking is determined by operating the rice cooking switch 39a after detecting the operation of the reservation switch 39b. And the difference with the following rice cooking process differs only in the point which waits until it becomes the rice cooking start time which divided the rice cooking time from the rice cooking start time or the cooking time. In addition, the processes from step S1 to step S5 are always performed in parallel even during execution of the rice cooking process and the heat insulation process described below.

  In the rice cooking process, as shown in FIG. 5, the microcomputer 40 first inputs 1 to a flag fa which means that the rice cooking process is being executed in step S10.

  Thereafter, in step S11, energization of the induction heating coil 14 is started, and a preheating process is performed in which the temperature is adjusted so that the temperature of the inner pot 10 is about 50 ° C. and heated.

  And when a preheating process is complete | finished when preset time passes, the pressurization in the inner pot 10 is started by starting energization to the solenoid 24 and turning on the relief valve 22 by step S12. Thereafter, in step S13, the pressure segment 33 is turned on (see FIG. 9A), and then in step S14, the pressure segment 33 is turned on, that is, a flag fb indicating that the pressure is applied. 1 is input to step S15, S16.

  In steps S15 and S16, the temperature raising step and the capacity determination step are performed in parallel. In the temperature raising step of step S15, the induction heating coil is energized with 100% (full power) to boil the water containing the rice in the inner pot 10. Moreover, the capacity | capacitance discrimination | determination process of step S16 discriminate | determines the rice cooking capacity accommodated in the inner pot 10 with the rising gradient of the temperature of the inner pot 10 during heating, and memorize | stores the determined rice cooking capacity in RAM44. . Note that the pressure injection start in step S12 and the temperature raising step in step S15 are executed substantially simultaneously.

  When the temperature raising process ends, in step S17, the boiling heating maintaining process is executed by controlling the induction heating coil 14 based on the input values of the lid temperature sensor 25 and the pressure sensor 26. When the boiling maintenance process is completed by elapse of a preset time, in step S18, the energization amount for the induction heating coil 14 is increased and the cooking process is executed.

  If the dry-up in the inner pot 10 is detected based on the detected temperature in the cooking process, the uneven process in step S19 and the pressure segment first display change process in step S20 are processed in parallel. In the unevenness process, the energization to the solenoid 24 is cut off, and the pressure input to the inner pot 10 is released. Then, energization of the body heater 15 and the lid heater 19 is started, while the energization of the induction heating coil 14 is interrupted. The pressure segment first display changing process is for turning off the display of the pressure segment 33, and will be described in detail later.

  When the unevenness process is finished by elapse of a preset time, in step S21, 0 is input to fa so as to mean that the rice cooking process is finished, the rice cooking process is finished, and then the heat retaining process. Migrate to

  Next, the pressure segment first display change process in step S20 will be described. The first display change process is performed when operating with power from the commercial power supply 41 (normal mode).

  In this first display change process, the microcomputer 40 first detects the pressure in the inner pot 10 by the pressure sensor 26 in step S20-1, as shown in FIG. In step S20-2, it is determined whether or not the detected pressure P is less than the reference pressure P0 stored in the ROM 43 in advance. If P ≧ P0, the process proceeds to step S20-3, and the detection count n is set to 0, and the process returns to step S20-1. On the other hand, if P <P0, the process proceeds to step S20-4, 1 is added to the number of detections n, and the process proceeds to step S20-5.

  In step S20-5, it is detected whether or not the number of detections n is 3. If n = 3, the process proceeds to step S20-6. If n = 3, the process returns to step S20-1.

  In step S20-6, after the pressure segment 33 is turned off, the pressure segment 33 is turned off, and 0 is input to the flag fb to mean that the pressure in the inner pot 10 is lower than the reference pressure. Return. That is, in the present embodiment, the pressure segment 33 is turned off when P <P0 is detected three times in succession.

  Next, the power failure process (backup mode) in step S2 will be described. Note that this power failure process operates with the power of the primary battery 42 when the power from the commercial power supply 41 is cut off and the remaining capacity of the primary battery 42 satisfies the reference value. The interruption of the electric power from the commercial power supply 41 may be due to a general power failure due to a natural disaster or the like and an artificial action by the user pulling out the power cord.

  In this power failure process, as shown in FIG. 7, the microcomputer 40 first executes a time counting process in which the elapsed time is measured by a timer and the current time of the liquid crystal display panel 28 is updated in step S30.

  Next, in step S31, whether or not a power failure has occurred during the rice cooking process is detected based on whether or not 1 is input to fa. If fa is 1, that is, if a power failure occurs during the rice cooking process, the process proceeds to step S32. If fa is 0, that is, if the rice cooking process is not performed before the power failure, the process returns. To do.

  In step S32, it is detected whether or not a flag fc indicating whether or not the power failure time is measured by a timer is zero. If fc is 0 (not measuring), the process proceeds to step S33. If fc is 1 (measuring), the process proceeds to step S36.

  In step S33, the rice cooking process at the time of a power failure, that is, the stage where the rice cooking process is completed is stored in the RAM 44. Thereafter, in step S34, the power failure time measurement timer is reset and started, and then in step S35, 1 is input to fc to store the fact that the power failure time is being measured, and the process proceeds to step S36.

  In step S36, whether or not the inside of the inner pot 10 before the power failure is higher than the reference pressure is detected by whether or not 1 is input to fb. If fb is 1 (higher than the reference pressure), the process proceeds to step S37, the pressure segment second display change process is executed, and the process returns. On the other hand, when fb is 0 (lower than the reference pressure), the process returns as it is.

  Next, the pressure segment second display change process in step S37 will be described. The second display change process is performed when operating with the power from the primary battery 42 (backup mode).

  In the second display change process, as shown in FIG. 8, first, in step S37-1, the microcomputer 40 sets the display time of the pressure segment 33 and means whether or not the set time is measured. It is detected whether the flag fd to be executed is 0 or not. If fd is 0 (not measuring), the process proceeds to step S37-2, and if fd is 1 (measuring), the process proceeds to step S37-7.

  In step S37-2, after the pressure segment 33 is displayed blinking (see FIG. 9B), in step S37-3, the rice cooking capacity determined during the rice cooking process and the pressure detected immediately before the power failure are stored in the RAM 44. Read. Thereafter, in step S37-4, the display time of the pressure segment 33, that is, the inside of the inner pot 10 is the reference pressure based on the detected pressure and the calculation formula of the pressure decreasing gradient corresponding to the rice cooking capacity in the rice cooking process at the time of power failure. Calculate (estimate) and set the time to descent below. Next, in step S37-5, a display time measurement timer for measuring the elapse of the set time is started, and in step S37-6, 1 is input to fd to store the state where the set time is being measured. .

  Next, in step S37-7, it is detected whether or not the display time measurement timer being measured has been counted up (elapsed). If the count is up, the process proceeds to step S37-8. If the count is not up, the process returns.

  In step S37-8, after the display time measurement timer is stopped, the pressure segment 33 is turned off in step S37-9. Then, in step S37-10, in order to memorize that the display time measurement timer is not measuring while inputting 0 to fb in order to memorize the state where the inside of the inner pot 10 is lower than the reference pressure. Return 0 to fd.

  Thus, in this embodiment, in the normal mode which operates with the electric power from the commercial power supply 41, when the inside of the inner pot 10 is in a higher pressure state than the reference pressure by the rice cooking process, the pressure segment 33 is displayed, and the pressure The pressure is detected by the sensor 26 every predetermined time, and when the pressure becomes lower than the reference pressure, the pressure segment 33 is turned off. Therefore, sufficient safety can be ensured when the user opens the lid 17.

  Moreover, in this embodiment, at the time of a power failure in which the internal pressure of the inner pot 10 cannot be detected by the pressure sensor 26, the internal pressure of the inner pot 10 is lower than the reference pressure based on the pressure detected immediately before the power failure and a preset pressure decrease gradient. Set the time until. Moreover, the calculation formula based on the pressure drop gradient is configured to be changed based on the rice cooking capacity determined at the time of rice cooking. Therefore, the pressure segment 33 can be turned off almost accurately without including unnecessary waiting time, and the user can be notified of the state where the pressure has dropped to a safe pressure quickly.

  Furthermore, in the state where the power from the commercial power supply 41 is cut off, the pressure segment 33 is displayed with the power from the primary battery 42 as the backup power supply, so that sufficient safety can be ensured even during an unintended power outage. .

  In addition, the pressure cooker of this invention is not limited to the structure of the said embodiment, A various change is possible.

For example, in the above embodiment, the display state of the pressure segment 33 is changed based on the pressure detected by the pressure sensor 26 and a preset pressure decrease gradient. However, the pressure and the temperature have a correlation with each other. Therefore, based on the temperature detected in the inner pan 10 by the lid temperature sensor 25 when the pressure is released and the temperature descending gradient obtained by converting the pressure into the temperature as shown in FIG. It is also possible to set a time to decrease to a temperature corresponding to and to change the display of the pressure segment 33 after the set time has elapsed.
Alternatively, the temperature detected by the lid temperature sensor 25 is converted into a corresponding estimated pressure based on the correlation, and the time to decrease to the reference pressure is set based on the estimated pressure and the pressure decrease gradient shown in the embodiment. The display of the pressure segment 33 may be changed after the set time has elapsed.
If it does in this way, even if it is a pressure rice cooker which does not mount the pressure sensor 26, safety | security can be ensured reliably.

  Further, in the above embodiment, the display time of the pressure segment 33 is set by the detected pressure when the pressure is released (immediately before) and the calculation formula based on the preset pressure decrease gradient. In addition, a plurality of detected pressures and rice cooking capacities and a plurality of set times corresponding to them may be stored in advance in the ROM 43 as a data table.

  Furthermore, in the above-described embodiment, in the normal mode, the pressure sensor 26 detects the internal pressure of the inner pot 10 every predetermined time, compares the detected pressure with the reference pressure, and changes the display of the pressure segment 33 (first). In this state, the display may be changed (second display change process) based on the detected pressure or the detected temperature and the descending gradient or the data table. In this case, it is preferable that the detected pressure or the detected temperature is detected by the pressure sensor 26 or the temperature sensor immediately after the pressure is released and the detected value is used.

  And in the said embodiment, although it was set as the structure which performs a 2nd display change process at the time of a power failure, when a user stops the rice cooking process by operating the switch 39e during execution of a rice cooking process, When the inside of the inner pot 10 is pressurized immediately before the stop, it is preferable to similarly execute the second display change process.

  Of course, in the above-described embodiment, when the process shifts to the unevenness process, the pressure input by the relief valve 22 is released, but this pressure input release timing is changed according to the user's preference. For this reason, it is preferable that the display change process is executed using the time when the pressure is released as a trigger point, and the time for changing the display of the pressure segment 33 is set.

  Further, in the embodiment, the state that the internal pressure of the inner pot 10 is higher than the reference pressure is displayed by the pressure segment 33 provided on the liquid crystal display panel 28, but the operation panel 27 is provided with the characters “pressure”. The user may be informed by disposing an LED in the corresponding portion to turn on, blink, and turn off.

  And the apparatus which provides a pressure display part like this invention is not restricted to a pressure rice cooker, It can apply similarly to the cooker which cooks a predetermined cooking material, and can acquire the same effect | action and effect.

It is the schematic which shows the structure of the rice cooker which is a pressure cooker of this invention. It is a front view which shows the operation panel of a rice cooker. It is a graph which shows the relationship between time, decompression force, and temperature. It is a flowchart which shows the control by a microcomputer. It is a flowchart which shows the rice cooking process by a microcomputer. It is a flowchart which shows the 1st display change process of FIG. It is a flowchart which shows the power failure process of FIG. It is a flowchart which shows the 2nd display change process of FIG. (A) is a front view which shows the display state at the time of a rice cooking process, (B) is a front view which shows the display state at the time of a power failure.

Explanation of symbols

10 ... inner pot 11 ... main body 14 ... induction heating coil (heating means)
16 ... Temperature sensor for inner pot (temperature detection means)
17 ... Lid 21 ... Exhaust passage 22 ... Relief valve (pressure injection means)
25. Temperature sensor for lid (temperature detection means)
26 ... Pressure sensor (pressure detection means)
27 ... Operation panel 33 ... Pressure segment (pressure display)
40 ... Microcomputer (control means)
40a ... Voltage discrimination unit 40b ... Timer 41 ... Commercial power supply 42 ... Primary battery (backup power supply)

Claims (4)

A main body having a pan for containing an object to be heated;
A heating means disposed in the body for heating the pan;
A lid for closing the pan;
An exhaust passage provided in the lid for communicating the inside and outside of the pan;
A pressure input means provided in the lid, capable of pressurizing the inside of the pan by closing the exhaust passage, and opening the exhaust passage to balance the pressure in the pan with an external pressure;
Control means for cooking by controlling the heating means and the pressure input means according to a preset program;
In a pressure cooker with
Provided with pressure detection means for detecting the pressure in the pan, provided with a pressure display unit for displaying the pressure state in the pan based on the pressure detected by the pressure detection means, and
A backup power source is provided for operating the control means and the pressure display unit during a power failure,
The control means recognizes whether the operation is based on the commercial power supply or the backup power supply based on the input voltage, and when the pressure input into the pan by the pressure input means is canceled due to a power failure, Based on the pressure detected by the pressure detection means at the time of release and a preset pressure drop gradient or data table, set the time for the inside of the pan to fall below a preset reference pressure, after the set time has elapsed, A pressure cooker characterized in that the display state of the pressure display section is changed. A main body having a pan for containing an object to be heated;
A heating means disposed in the body for heating the pan;
A lid for closing the pan;
An exhaust passage provided in the lid for communicating the inside and outside of the pan;
A pressure input means provided in the lid, capable of pressurizing the inside of the pan by closing the exhaust passage, and opening the exhaust passage to balance the pressure in the pan with an external pressure;
Control means for cooking by controlling the heating means and the pressure input means according to a preset program;
In a pressure cooker with
Provided with a temperature detecting means for detecting the temperature of the pot or the pot, and a pressure display section for displaying the pressure state in the pot based on the estimated pressure in the pot corresponding to the temperature detected by the temperature detecting means and,
A backup power source is provided for operating the control means and the pressure display unit during a power failure,
The control means recognizes whether the operation is based on the commercial power supply or the backup power supply based on the input voltage, and when the pressure input into the pan by the pressure input means is canceled due to a power failure, Based on the temperature detected by the temperature detecting means at the time of release and a preset temperature decrease gradient or data table, a time for the pan to fall below a preset reference temperature is set, and after the set time has elapsed The pressure cooker characterized in that the display state of the pressure display section is changed. A main body having a pan for containing an object to be heated;
A heating means disposed in the body for heating the pan;
A lid for closing the pan;
An exhaust passage provided in the lid for communicating the inside and outside of the pan;
A pressure input means provided in the lid, capable of pressurizing the inside of the pan by closing the exhaust passage, and opening the exhaust passage to balance the pressure in the pan with an external pressure;
Control means for cooking by controlling the heating means and the pressure input means according to a preset program;
In a pressure cooker with
Provided with a temperature detecting means for detecting the temperature of the pot or the pot, and a pressure display section for displaying the pressure state in the pot based on the estimated pressure in the pot corresponding to the temperature detected by the temperature detecting means and,
A backup power source is provided for operating the control means and the pressure display unit during a power failure,
The control means recognizes whether the operation is based on the commercial power supply or the backup power supply based on the input voltage, and when the pressure input into the pan by the pressure input means is canceled due to a power failure, Based on the estimated pressure corresponding to the temperature detected by the temperature detecting means at the time of release and a preset pressure drop gradient or data table, a time for the inside of the pan to fall below a preset reference pressure is set, A pressure cooker, wherein the display state of the pressure display unit is changed after a set time has elapsed.   The control means determines the capacity of the object to be heated based on the temperature rise gradient detected during heating by the heating means, and the descent slope or the data table is changed according to the determined capacity. The pressure cooker according to any one of claims 1 to 3.

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