JP3230979B2 - rice cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rice cooker, and more particularly, to a structure for adjusting pressure in a rice cooker.

[0002]

2. Description of the Related Art Conventionally, there is known a rice cooker having a pressure regulating valve on a lid to cook sticky delicious rice at a high boiling temperature (JP-A-6-30846, JP-A-6-846). No. 22710). The pressure regulating valve of this rice cooker closes an exhaust port provided on the lid by its own weight, and is automatically pressurized by the rise in temperature inside the rice cooker after the start of rice cooking. The pressure regulating valve is pushed up by the pressure to release the pressure.

[0003]

However, in the above-mentioned conventional rice cooker, since the pressure regulating valve is closed from the beginning, it is not possible to freely select the time of pressurizing, and the rice cooker is effective in accordance with the rice cooking menu and the rice cooking capacity. Could not cook rice under pressure. Also, if the pressure regulating valve is closed from the beginning, the rice is in a pressurized state from the beginning of rice cooking, convection is less likely to occur in the rice cooker, and the variation in the cooking condition of the upper and lower rice is increased.

The present invention has been made in view of such conventional problems, and it is an object of the present invention to provide a rice cooker capable of freely setting a pressurizing time during rice cooking.

[0005]

Means for Solving the Problems In order to solve the above problems, the present invention provides a rice cooker, a main body for containing the rice cooker,
In a rice cooker which is attached to the main body so as to be openable and closable and seals the rice cooker, and a heating device for heating the rice cooker, an exhaust outlet for discharging steam in the rice cooker to the lid. Opening the exhaust port before cooking and early rice cooking, closing the exhaust port during rice cooking and switching the pressure in the rice cooker from a non-pressurized state to a pressurized state, and an exhaust port opening / closing means, Control means for changing the timing of closing the exhaust port.

According to the configuration of the present invention, before the rice cooking and at the beginning of the rice cooking, the exhaust port opening / closing means opens the exhaust port to be in the non-pressurizing mode, so that the rice cooking is started at atmospheric pressure. And
During the rice cooking operation, the exhaust port opening / closing means closes the exhaust port to set the pressure mode, so that the rice is cooked in a pressurized state. By changing the timing at which the exhaust port is closed by the exhaust port opening / closing means, the pressurizing time can be set freely.

[0007] The exhaust port opening / closing means may change the timing of closing the exhaust port according to a rice cooking menu. In the case where it is preferable to promote convection by heating under atmospheric pressure such as white rice, the pressurizing time is set as late as possible. When it is preferable to cook rice in a pressurized state, such as brown rice, the pressurizing time is set as early as possible. In this way, it is possible to perform the optimal rice cooking according to the rice cooking menu.

[0008] The exhaust port opening / closing means may change the timing of closing the exhaust port according to the rice cooking capacity. When the rice cooking capacity is large, it is necessary to heat at atmospheric pressure to promote convection, so the pressurizing time is made as late as possible. Conversely, when the cooking capacity is small, stickiness is less likely to occur, so the pressing time is set earlier. As described above, it is possible to perform the optimal rice cooking according to the rice cooking capacity.

[0009] The exhaust port opening / closing means includes a pressure regulating ball disposed opposite to the exhaust port, retracts the pressure regulating ball from the exhaust port before rice cooking and at the beginning of rice cooking, and moves the pressure regulating ball during rice cooking. It is preferable that the pressure regulating ball drive mechanism be dropped into the exhaust port. In this case, the pressure adjusting ball driving mechanism may be formed of a solenoid or an electromagnet.

[0010]

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows a schematic configuration of a rice cooker according to the present invention. This rice cooker has a main body 2 in which a heating plate 1 is arranged on the inner bottom.
A rice cooker 3 accommodated on the heating plate 1 of the main body 2, and a rice cooker 3 attached to the main body 2 so as to be opened and closed by a hinge 4,
A lid 6 having an inner lid 5 for covering an upper end opening of the rice cooker 3; The body 2 is provided with a side temperature sensor 7 for detecting the temperature of the rice cooker 3 by contacting the outer surface of the rice cooker 3. A lid temperature sensor 8 for detecting is provided.

The lid 6 has an exhaust port 9 communicating with the outside. As the exhaust port opening / closing means for opening / closing the exhaust port 9, a pressure regulating ball 10 arranged to face the exhaust port 9 from above and a solenoid 11 as a driving means of the pressure regulating ball 10 are provided. Have been. The pressure regulating ball 10 is pressed by the plunger 12 of the solenoid 11 and retracted from the exhaust port 9 before or during the rice cooking.

The main body 2 includes a heater drive circuit 13,
A solenoid drive circuit 14 and a control device 15 including a microcomputer are provided. The heater drive circuit 13 heats the rice cooker 3 based on a drive signal from the control device 15 by energizing a heater (not shown) embedded in the heating plate 1. Solenoid drive circuit 14
The solenoid 11 is driven based on a drive signal from the control device 15 so that the retracted pressure adjusting ball 10 is dropped into the exhaust port 9 by its own weight. The control device 15 includes a timer 19 for measuring time, the timer 1
9, the temperature detected by the temperature sensors 7 and 8, the rice cooking menu selected by operating an operation display panel (not shown), the rice cooking capacity determined by the central processing unit described later during rice cooking RA that stores etc.
M memory 16 and a ROM memory 17 for storing a predetermined rice cooking program and setting values required for executing the program
And a central processing unit (hereinafter, simply referred to as a CPU) 18 that executes the rice cooking process in cooperation with the timer 19.

The CPU 18 of the control device 15 has a ROM
In accordance with the program stored in the memory 17, the rice cooking operation is performed by sequentially executing the steps of preheating, medium heat, power control, spotting, and heat retention. Further, the CPU 18 determines the time measured by the timer 19 and the rice cooker 3
From the detected temperature, the rice cooking capacity is determined based on the rate of temperature rise per predetermined time. Further, the CPU 18 performs an operation of switching the pressure in the rice cooker from the non-pressurizing mode to the pressurizing mode when a predetermined pressurizing time comes during the cooking of rice. That is,
Before rice cooking or early rice cooking, a signal is not output to the solenoid drive circuit 14, but the pressure regulating ball 10 is pressed by the plunger 12 of the solenoid 11 to be in the non-pressurized mode retracted from the exhaust port 9. Then, when a predetermined pressurizing time comes during the rice cooking process, a signal is output to the solenoid drive circuit 14 to drive the solenoid 11 to drop the pressure adjusting ball 10 into the exhaust port 9 to set the pressurizing mode. It is.

Next, the switching operation from the non-pressurizing mode to the pressurizing mode by the CPU 18 will be described with reference to the flowchart of FIG.

First, when rice cooking is started, it is determined in step 101 what the selected rice cooking menu is.
If the cooked rice menu is white rice, the signal is not output to the solenoid drive circuit 14 in step 102, and the non-pressurized mode is set in which the pressure regulating ball 10 is retracted from the exhaust port 9 and the valve is kept open. Next, it is determined in step 103 how much the determined rice cooking capacity is. If the capacity is large, the temperature detected by the lid temperature sensor 8 becomes 90 in step 105.
If the temperature is lower than 90 ° C., the valve is kept open.
At 7, a signal is output to the solenoid drive circuit 14 to drive the solenoid 11, and the pressure regulating ball 10 is dropped into the exhaust port 9 by its own weight, thereby closing the valve and setting the pressure mode.

When the capacity is normal or small, the same steps as those in the case where the capacity is large are performed, but the time when the valve is closed to enter the pressurization mode is different. That is, if the capacity is normal, if the detected temperature of the lid temperature sensor 8 is less than 87 ° C. in step 108, the valve is kept open,
If the temperature exceeds ℃, after waiting for a certain time in step 109,
In step 107, the valve is closed to set the pressure mode. If the capacity is small, the valve is kept open if the detected temperature of the lid temperature sensor 8 is less than 83 ° C.
If this is the case, after waiting for a certain period of time in step 111, the valve is closed in step 107 to set the pressure mode.

If the rice cooking menu is rice porridge, the signal is not output to the solenoid drive circuit 14 in step 112, and the pressure adjusting ball 10 is retracted from the exhaust port 9 to set the non-pressurizing mode in which the valve remains open. deep. If the detected temperature of the lid temperature sensor 8 is lower than 85 ° C. in step 113, the valve is kept open, and if it is higher than 85 ° C., the valve is closed in step 114 to set the pressure mode.

If the cooked rice menu is brown rice, no signal is output to the solenoid drive circuit 14 in step 115, and the pressure adjusting ball 10 is retracted from the exhaust port 9 to set the non-pressurized mode in which the valve remains open. deep. Then, after waiting for a certain period of time from the start of rice cooking in step 116, step 1
At 17 the valve is closed to enter the pressurization mode.

As described above, the timing of changing from the non-pressurizing mode to the pressurizing mode, that is, the pressurizing time is changed according to the rice cooking menu and the rice cooking capacity. In the case of white rice, the pressurizing time is changed according to the rice cooking capacity, and the pressurizing time is delayed as the rice cooking capacity increases. In the case of rice porridge, since the amount of rice is small and the amount of water is large, the pressing time is fixed regardless of the cooking capacity. As described above, in the case of white rice and porridge, the non-pressurized mode is set in the early stage of rice cooking, and the pressurized mode is set when the detected temperature reaches 83 to 90 ° C. and starts boiling. The convection in the inside is promoted, and the rice is cooked up and down evenly. Further, in the case of brown rice, since the effect of improving softness and stickiness by pressurizing is greater than uneven cooking, the pressurizing time is earlier regardless of the cooking capacity.

In the above embodiment, the solenoid 11 is used as the pressure regulating ball driving mechanism of the exhaust port opening / closing means, but the following mechanism may be employed instead.

The one shown in FIG. 3 uses an electromagnet 21 as a pressure adjusting ball driving mechanism. In the non-pressurizing mode, the pressure adjusting ball 10 is attracted by exciting the electromagnet 21 and retracted from the exhaust port 9.
And the pressure adjusting ball 10 is dropped into the exhaust port 9 by its own weight. As a similar mechanism, a permanent magnet is used in place of the electromagnet 21, and in the non-pressurization mode, the permanent magnet is brought close to the pressure adjusting ball 10 so that the pressure adjusting ball 10 is sucked and retracted from the exhaust port 9. In the pressure mode, the pressure regulating ball 10 may be dropped into the exhaust port 9 by its own weight by moving the permanent magnet away.

[0024]

[0025]

Next, a more specific embodiment of the exhaust port opening / closing means using a solenoid 11 as a pressure regulating ball driving mechanism will be described with reference to FIG.

The cover 6 comprises a cover lower plate 31 and a cover upper plate 32. A radiator plate to which a lid heater 33 is attached is attached to a lower surface of the lid lower plate 31 by a screw (not shown). An opening 34 is formed substantially at the center of the lid lower plate 31, and a packing 35 is attached to an edge of the opening 34. A flange 35a for attaching an inner lid 5 described later is formed on the inner periphery of the packing 35. An annular groove 35b is formed at the upper end of the packing 35, and the lower end of the steam dome 36 is fitted into the annular groove 35b. A steam outlet 37 is formed on the upper surface of the steam dome 36. An opening 38 is formed on the side surface of the steam dome 36, and a flexible partition 39 is attached to the opening 38. In the center of the partition wall 39, a steam dome 36 is provided.
A bulging portion 39a that protrudes in a bar shape inward is formed, and a slack is provided around the bulging portion 39a so that the partition wall 39 can move in and out.

On the upper surface of the lid lower plate 31, the solenoid 11 is installed along the radiation passing through the center of the steam dome 36. The plunger 12 of the solenoid 11 projects on the side opposite to the steam dome 36. Also, the lid lower plate 31
As shown in FIG. 5, a rectangular frame-shaped drive case 40 surrounding the solenoid 11 is disposed on the upper surface of the drive case 40. The drive case 40 has rails 4 formed on both sides of the bottom thereof.
1, 41 (only one is shown) is engaged with a guide rail 42 (only one is shown) formed on the upper surface of the lid lower plate 31 to be slidably provided along the axial direction of the solenoid 11. . The rails 41 of the drive case 40 extend in a direction away from the steam dome 36 (hereinafter, this direction is referred to as rearward, and the opposite direction is referred to as forward).
have. A coil spring 43 is provided between the solenoid 11 and a wall of the drive case 40 on the side facing the steam dome 36 (hereinafter referred to as a front wall, and the opposite side is referred to as a rear wall).
The drive case 4 is provided by the coil spring 43.
0 is biased toward the steam dome 36.

As shown in FIG. 4, a drive shaft 44 projects from the front wall of the drive case 40. The drive shaft 44 is inserted into the bulge 39a of the steam dome 36.
On the other hand, on the rear wall of the drive case 40, the solenoid 11
Of the plunger 12 and the plunger 12
The plunger case 45 with which the tip of the plunger contacts is extended. Accordingly, when the solenoid 11 is not excited, the drive case 40 is pressed by the coil spring 43 and moves forward toward the steam dome 36. Conversely, when the solenoid 11 is excited, the plunger 12 is moved backward. , And presses the plunger case 45 of the drive case 40, so that the drive case 40 moves backward against the coil spring 43.

The open end of the lower cover plate 31 has an inverted L section.
A hook 46 in the shape of a letter is rotatably attached by a pin 47. At the vertical end portion 48 of the hook 46, an engaging portion 50 that protrudes downward from the lid lower plate 31 and engages with an engaging concave portion 49 formed in the main body 2 is formed. Also,
Between the pin 47 of the hook 46 and the engaging portion 50, a tongue piece 54 projecting from above from the engaging projection 53 of the hook button 52 rotatably attached to the main body 2 by the pin 51 is provided. On the other hand, the horizontal end 55 of the hook 46 extends to the vicinity of the drive case 40 of the solenoid 11. When the drive case 40 is in the forward position, the extension 41a of the rail 41 is retracted from the edge of the horizontal end 55 of the hook 46. When the drive case 40 is in the retracted position, the extension 41a of the rail 41 is Is located below the horizontal end 55 of the hook 46 to prevent the rotation of the hook 46. Also, the horizontal end 55 of the hook 46
Is formed with a notch 56 so as not to interfere with the plunger case 45 of the drive case 40. The hook 46 is urged by a torsion spring 57 in a direction in which the engaging portion 50 is engaged with the engaging concave portion 49.

The upper cover plate 32 is attached so as to cover the lower cover plate 31 from above. At the approximate center of the lid upper plate 32, an opening 58 is formed to expose the upper surface of the steam dome 36 attached to the lid lower plate 31.

The inner lid 5 has an outer peripheral groove 59 formed by folding an outer peripheral edge of the inner lid 5 downward.
Is provided with an inner lid packing 60. An opening 61 is formed substantially at the center of the inner lid 5, and a lower case 62 for accommodating the pressure adjusting ball 10 is inserted into the opening 61 from above. The lower case 62 is fixed to the inner lid 5 by screwing a nut 64 into a male screw portion 63 formed at a portion protruding downward from the opening 61 of the inner lid 5. A cylindrical upper case 66 having a closed upper end is attached to a male screw portion 65 formed at a portion protruding above the lower case 62. The pressure regulating ball 10 is housed in a space formed by the upper case 66 and the lower case 62.

The lower case 62 has an exhaust port 9 which is closed by the pressure regulating ball 10, and the upper case 66 and the outer peripheral wall have ventilation holes 67. Further, a hole 68 through which the drive shaft portion 44 of the drive case 40 penetrates is formed on the outer peripheral wall of the upper case 66. Also,
Around the exhaust port 9 of the lower case 62, a plurality of ribs 69 on which the pressure regulating ball 10 can ride can be formed radially. A plurality of drain holes 70 are formed around the male screw portion 65 of the lower case 62, and the drain holes 70 are lowered by a check valve 71 sandwiched between the nut 64 and the lower case 62. Is closed from.

The inner lid 5 engages an engaging portion 72 formed on the outer periphery of the lower case 62 with a flange 35a formed on the inner periphery of the packing 35 in the opening 34 of the lower cover plate 31. Thereby, it is detachably attached to the lid lower plate 31. When the lid 6 is closed, the outer peripheral edge of the inner lid 5 is pressed against the bent portion of the upper edge of the rice cooker 3, while the lower end of the inner lid packing 60 contacts the inner peripheral surface of the rice cooker 3. do it,
When the pressure in the rice cooker 3 rises during rice cooking, the lower end of the inner lid packing 60 is deformed and comes into pressure contact with the inner peripheral surface of the rice cooker 3.

The solenoid 1 of the lid 6 having the above configuration
1 and the operation of the pressure regulating ball 10 and the operation of the hook 46 in connection with this.

When the solenoid 11 is not excited,
That is, before rice cooking or early rice cooking, the drive case 40 is urged by the coil spring 43 and moves forward, and the drive shaft 44 presses the pressure regulating ball 10. As a result, the pressure regulating ball 10 moves by riding on the rib 69,
As shown by a two-dot chain line in FIG. For this reason, the inside of the rice cooker 3 has an exhaust port 9 and a vent 6
7 and the outside through a steam outlet 37. Therefore, in the early stage of rice cooking, rice cooking is started in a non-pressurized state. In this state, the rail 41 of the drive case 40
Since the extension 41a of the hook 46 is retracted from the edge of the horizontal end 55 of the hook 46, when the hook button 52 is pressed, the engaging projection 53 pushes the tongue piece 54 of the hook 46 upward, and as a result, the hook 46 is In FIG. 4, the clockwise rotation is performed, the engagement between the engagement portion 50 and the engagement recess 49 is released, and the lid 6 is opened.

Next, when the rice cooks and starts to boil, the solenoid 11 is excited. As a result, the plunger 12 projects rearward and presses the drive case 40, so that the drive case 40 retreats backward against the urging force of the coil spring 43, and the drive shaft portion 44 separates from the pressure regulating ball 10. .
As a result, the pressure adjusting ball 10 is moved by its own weight to the rib 69.
It rolls down above and closes the exhaust port 9 as shown by the solid line in FIG. Therefore, thereafter, rice cooking is continued in a pressurized state. In this state, since the extension 41a of the rail 41 of the drive case 40 is located below the horizontal end 55 of the hook 46, the clockwise rotation of the hook 46 in FIG. Therefore, by mistake hook button 5
Even if 2 is pressed, the lid 6 is not opened and the pressurized state is maintained.

[0038]

As is clear from the above description, according to the present invention, the exhaust port opening / closing means for opening the exhaust port before and during the initial stage of rice cooking, closing the exhaust port during rice cooking, and applying pressure to the inside of the rice cooker. Is provided, it is possible to freely set the pressurizing time, and it is possible to perform optimal rice cooking according to the rice cooking menu and the rice cooking capacity.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a rice cooker according to the present invention.

FIG. 2 is a flowchart of an opening / closing operation of an exhaust port opening / closing means of the rice cooker shown in FIG.

FIG. 3 is a schematic sectional view showing another embodiment of the exhaust port opening / closing means.

FIG. 4 is a sectional view of a lid of a rice cooker provided with a more specific embodiment of an exhaust port opening / closing means.

FIG. 5 is a perspective view showing a state where a cover upper plate of the cover of FIG. 4 is removed.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Heating plate, 2 ... Body, 3 ... Rice cooker, 6 ... Lid, 9 ... Exhaust port, 10 ... Pressure regulating ball, 11 ... Solenoid, 21 ... Electromagnet.

Continuation of the front page (56) References JP-A-9-37934 (JP, A) JP-A-9-164071 (JP, A) JP-A-9-164063 (JP, A) JP-A-9-140576 (JP) JP-A-6-181838 (JP, A) JP-A-5-228053 (JP, A) JP-A-57-25817 (JP, A) JP-A-4-40912 (JP, A) 57-7417 (JP, U) Jiko 58-36347 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) A47J 27/00

Claims (6)

(57) [Claims] 1. A rice cooker, and a main body containing the rice cooker,
In a rice cooker which is attached to the main body so as to be openable and closable and seals the rice cooker, and a heating device for heating the rice cooker, an exhaust outlet for discharging steam in the rice cooker to the lid. Opening the exhaust port before cooking and early rice cooking, closing the exhaust port during rice cooking and switching the pressure in the rice cooker from a non-pressurized state to a pressurized state, and an exhaust port opening / closing means, A rice cooker provided with control means for changing a timing of closing the exhaust port. 2. The rice cooker according to claim 1, wherein the exhaust port opening / closing means changes a timing of closing the exhaust port according to a rice cooking menu. 3. The rice cooker according to claim 1, wherein the exhaust port opening / closing means changes a timing at which the exhaust port is closed according to a rice cooking capacity. 4. The exhaust port opening / closing means includes: a pressure regulating ball disposed opposite to the exhaust port; and evacuation of the pressure regulating ball from the exhaust port before and during rice cooking, and the pressure regulating ball during rice cooking. The rice cooker according to any one of claims 1 to 3, further comprising a pressure regulating ball driving mechanism for dropping a ball into the exhaust port. 5. The rice cooker according to claim 4, wherein the pressure adjusting ball drive mechanism is formed of a solenoid. 6. The rice cooker according to claim 4, wherein the pressure adjusting ball driving mechanism is made of an electromagnet.