JPS5856589Y2 - electric rice cooker - Google Patents

Description

[Detailed description of the invention] The present invention relates to an improvement of an electric rice cooker, and in particular, an electric rice cooker that reliably shuts off power to the rice cooker when the user falls asleep during rice cooking and takes out the inner pot. It provides equipment.

The following description will be given based on the drawings: 1 is a cylindrical frame; 2 is a bottomed cylindrical outer pot that is fitted inside the frame 1 with a heat insulating material 3 interposed therebetween and has a bulging portion 4 at the bottom; This is a sheath-shaped rice cooking heater installed at the inner bottom of the pot 2.

Reference numeral 6 denotes an inner pot which is suspended from the outer pot 2 with a slight interval so that it can be stored freely, and an upper opening flange portion 7 is placed on the upper flange portion 8 of the outer pot 2.

Reference numeral 9 denotes an inner lid that covers the opening of the inner pot 6, and has an insertion hole 10 and a steam return hole 11 in the center, and a steam hole 12 on the outside.

Reference numeral 13 denotes a heat-insulating lid with good heat conduction, whose outer periphery is placed on the inner lid 9 to form the space A, and 14 a handle that is pivotally supported on one side to the frame 1 and can be hung on the other side. It is a dual-purpose outer lid, with a heat insulating material 15 inside and a cord-shaped top lid heater 16 attached to the inside of the back side.

Reference numeral 17 denotes a pressure locking mechanism provided at the center of the back surface of the outer lid 14, which is comprised of a spring 18, an elastic engagement body 19 that is always urged downward by the spring, and a locking rod 20 that is installed vertically. configured.

21 is a steam guide tube provided on one side of the heat-insulating lid 13;
Reference numeral 2 denotes a heat sensitive element which is energized so as to always protrude upward from the upper surface of the bulge 4 formed at the center of the outer lid 2, and 23 a thermal element, for example, which is attached in close contact with the outer wall of the outer pot 2. A heat-sensitive element like a reed switch for controlling the heat retention temperature, ONL from room temperature to around 70°, which is considered the optimum temperature for heat retention.
, is turned off at a temperature higher than 70°.

24 is a ring-shaped frame cover in which the outer pot 2 and the upper periphery of the frame 1 are fitted and fixed at a constant interval;
Reference numeral 25 denotes a cord-shaped side heater closely attached to the upper outer wall of the outer pot 2, which is composed of a first auxiliary heater 26 for temperature control and a second auxiliary heater 27 for continuous energization.

Reference numeral 28 denotes a switch cover attached to one side of the frame 1; 29, an arbitrary part is pivotally supported, one end is positioned inside the switch cover 28, an operation button 30 is attached; the other end is used to operate the heat sensitive element 22; A switch lever 32 is connected to the rod 31 and allows each end to operate in a seesaw manner, and is a bottom cover that also serves as a support leg that covers the bottom of the frame 1.

Next, the structure of the above-mentioned heat sensitive body that performs the double cooking and uneven heating operations will be explained based on FIGS. 2 to 5.
33 is a circular heat receiving plate with good heat conduction, 34 is a holding plate having a pair of holding parts 35 and 35, and 36 is a ferromagnetic material with high magnetic permeability (magnetic flux density) at room temperature as shown in Fig. 5. Constant temperature due to temperature rise (curi temperature...approximately 140°
), Mn and Cu become paramagnetic and have low magnetic permeability.
, is a temperature-sensitive ferrite composed of Zn ferrite, and is held and fixed by the holding portions 35 and 35.

37 is a substantially cylindrical storage case whose lower part is bent and extended inward; 38 is a waterproof cover with an upward cross section; and the holding plate 34.
The respective peripheral edges of the storage case 37 and the waterproof cover 38 are clamped and fixed by the heat receiving plate 33.

39 is a magnet fixed to the upper part of the operating rod 31;
0 is a metal fitting that penetrates the operating rod 31 and fixes the magnet 39, and is provided with a concave groove 41 on the outside and a protrusion 42 projecting downward on the inside.

43 is a ring that prevents the magnet holder from removing the metal fitting 40;
Reference numeral 44 denotes a first spring interposed between the groove 41 and the holding plate 34, which constantly presses the magnet 39 downward so as to separate it from the ferrite 36.

The first spring 44, the magnet I-39, the magnet holder, and the metal fitting 40 are stored in a storage case 37, and the magnet 39 is connected to the operating rod 3 by operating the switch lever 29.
1 moves up and down within the storage case 37.

Reference numeral 45 denotes a circular insulating base fixed to the lower part of the storage case 37 with screws (not shown), and terminal plates 46' and 47' each having contacts 46 and 47 facing each other on one side.
and a movable contact plate 50 having elasticity and having a hole 49 between the contacts 48 and the contacts 46 and 47 for switching contact with one of the contacts, and a terminal plate 48 electrically connected and fixed to the contact plate 50. ' and is covered with an upper insulating lid 51.

The contacts 46, 47, 48 and the terminal plates 46', 47', 4
8' and the movable contact plate 50 constitute the first switch (2), and the movable contact plate 50 is constructed so that the contact 48 is always in contact with the contact 47 side due to its own elasticity.

Reference numeral 52 denotes a cylindrical portion 53 that freely passes through the operating rod 31 and is provided at the bottom.
is a substantially funnel-shaped movable insulator that passes through the hole 49 of the movable contact plate 50; The installed second spring II is a second switch separated from the first switch I, which is connected only to the automatic mechanical operation by vertical movement of the operating rod 3, which separates the first switch I from the first switch I, and connects the common terminal 55 and the second switch. Two switching terminals 56 and 57 are provided, and normally (temperature-sensitive ferrite 36 and magnet 3
When 9 is adsorbed.

) is configured such that the common terminal 55 and one terminal 56 are in contact with each other, and when the operation button A is pressed, the common terminal 55 and the other terminal 57 are brought into contact with each other.

58 is a comparatively thick synthetic resin L-shaped mounting plate on which the second switch II is partially attached and fixed to the insulating base 45 with screws 59, and 60 is the L-shaped mounting plate as shown in FIG. A feather-shaped switching guide groove formed on a part of the forming plate 58 for switching and maintaining each operating state to be described later, and the groove is stepped down in steps in the direction of the arrow in FIG. 13. , and the height state of each part is shown in a cross section along A-J.

Reference numeral 61 denotes the movable insulator 52 attached to the appropriate position of the operating rod 31 when the magnet 39 and Ferrai I.36 are attracted.
62 is a retaining ring located at the lower part of the pressing ring 61 and attached and fixed to the operating rod 31; 63 is a retaining ring with one side relatively below the operating rod 31; A mounting plate 65 for a switching guide rod, which will be described later, is fixed with screws 64 and extended on the other side, with one end pivotally supported on the mounting plate 63, and the other end shaped like a pin and fitted into the switching guide groove 60 to form the guide. Groove 6
The switching guide rod is configured to be in sliding contact with the guide groove 60, and is always biased by a return spring 66 so that one end thereof comes into elastic contact with the bottom wall of the guide groove 60 and moves to the right in the drawing.

67 loosely penetrates the operating rod 31, and a retaining ring 62 is provided at the rear.
and a pressing fitting 69 for the operating button A, which has a suppressing piece 68 disposed between the pressing fitting 67 and the mounting plate 63, and is attached so as to separate them from each other. The biased third spring 70 is a stopper 71 attached to the peripheral edge of the bulging portion 4 of the outer pot 2 so as to protrude downward.
．． Reference numeral 71 designates a washer which is attached and fixed to the operating rod 31 so that the other end of the switch lever 29 is positioned above and below the switch lever 29 with some play in the vertical direction.

The bulging portion 4 is composed of a heat shield plate attached and fixed to the outer pot 2 so as to surround the waterproof cover 38, and prevents the radiant heat from the rice cooking heater 5 from directly hitting the ferrite etc. Furthermore, the upper end is bent inward to form the hook part 72.
is formed.

A fourth spring 73 is interposed between the waterproof cover 38 and the outer pot 2, and is energized so that the heat receiving plate 33 is always in close contact with the outer bottom surface of the inner pot 6.

Each part except the above-mentioned heat shield plate 4 and the brace 70 is constructed integrally, and each is constructed to be vertically movable by the fourth spring 73.

Next, to explain the electric circuit diagram shown in FIG. 6, a,
1) is a power supply terminal, and the upper lid heater 16 is connected to the supply terminals a and 1).

A rice cooking indicator C is connected in parallel to the rice cooking heater 5, and one end thereof is connected to the contact 46 of one terminal plate 46' of the first switch I, and the other end is connected to one terminal of the second switch II. It is connected to 56.

Terminal plate 48' on the movable contact plate 50 side of the first switch (3)
is connected to one supply terminal A, and the common terminal 55 of the second switch II is connected to the other supply terminal a.

d is a double cooking indicator connected to the common terminal 55 of the second switch II and the other terminal board 57;
Connect to the other switching terminal 57 of Switch II, and connect the other end to the first
The temperature indicator is connected to the contact 47 of the other terminal plate 47' of switch I, and the series circuit of the first auxiliary heater 26 for temperature control and the heat-sensitive element 23 is connected in parallel to the second auxiliary heater 27 for continuous energization. One end thereof is connected to the other switching terminal 57 of the second switch II, and the other end is connected to the contact 47 of the other terminal plate 47' of the first switch (2).

FIG. 15 shows another embodiment of the heat sensitive body, in which the external shape is molded from a disk-shaped heat receiving plate 33' made of aluminum or the like with good heat conduction and a cylindrical storage case 37'. Case 37' has iron adsorption plate 36' and magnet 39'.
The operating rod 31' fixed to the suction plate 36' and the heat receiving plate 3
A spring 44' is installed to constantly press down the operating rod 31' and the magnet 39'. It is supported by

Reference numeral 76 is fixed to the upper end of the operating rod 31', and a pressing portion passing through the suction plate 36' and the support plate 75 pushes down the operating rod 31' by reversing the bimetal plate 74.

Next, the operation will be described with reference to FIGS. 4 to 14.
First, set the calorific value of each heater as follows.

Rice cooking heater 5 is 600 W, top lid heater 16 is 18
．． 5W, the first auxiliary heater 26 is 50W, and the second auxiliary heater 27 is 20W.

Then, a predetermined amount of water and rice are put into the inner pot 6 and stored in the outer pot 2, and the inner pot 9, heat retaining lid 13, and outer lid 14 are integrated by the pressure locking mechanism 17, and the inner pot 6 and the outer pot 2 are Cover the opening.

At this time, the inner pot 6 comes into close contact with the heat receiving plate 33 of the heat sensitive body 22, and the heat sensitive body 22 is pushed down against the elasticity of the fourth spring 73.

Under normal conditions, the magnet 39 is shown in Figures 4 and 7.
, the magnet holder is a metal fitting 40, an operating rod 31 and a mounting plate 63.
The switching guide rod 65 is lowered, and the retaining ring 62 is removed.
The pressing metal fitting 67 hits and presses the operation button A, connecting the Tsukuda terminal 55 of the second switch II and the other switching terminal 57, and the first switch I also presses the second spring 54.
The contact 48 is connected to the other contact 47 because the movable insulator 52 presses the movable contact plate 50 downward against its elasticity.

Further, due to the lowered state of the mounting plate 63, the tip of the switching guide rod 65 is at position A shown in FIG.

Now, when the button 30 is pushed down and the other end of the switch lever 29 is pushed up in order to start cooking rice, the operating rod 31 moves upward against the first spring 44 and the magnet 39 is moved as shown in FIG. It is adsorbed to the warm ferrite 36.

At this time, the third spring 69 causes the pressing piece 68 of the pressing fitting 67 to come into contact with the stopper 70 formed below the peripheral edge of the bulging portion 4 of the outer pot 2, and the temperature-sensitive ferrite 36 is moved as shown in FIG. Since the magnetic flux density is high, it becomes a ferromagnetic material and holds the attraction of the magnet 39, so that the operating rod 31 is located at the upper position.

Then, as the above-mentioned operation rod 31 moves upward, the push ring 6
1 moves up, the movable insulator 52 is pushed up, and the movable contact plate 50 of the first switch (2) switches its contact 48 to one contact 46 due to its own elasticity, and the operation button (A) of the second switch II is pressed. After the return, the common terminal 55 is switched to one contact 56, and the respective ends of the rice cooking heater 5 are connected to the power supply terminals a and l) by the first and second switches I and II, and the output power is 600W. Generating heat and heating the bottom of the inner pot 6, the rice cooking indicator C lights up to indicate that the rice is being cooked.

Also, the tip of the switching guide rod 65 is moved from position A' to B in FIG.
'f2. However, as shown in FIG. 3, the tip of the guide rod 65 does not return to its original direction and maintains its current state because a step B'' is provided in the CD cross section of the switching guide groove 60.

On the other hand, the above-mentioned power supply terminal a. By applying power to b, the top lid heater 16 generates heat at 18.5W, and the rice cooking heater 5
The inner pot 6 is heated with a total of 618.5 W together with 600 W of Heat the pot 6 from above as well.

At this time, as shown in FIG. 14, the heat-sensitive element 23 is turned on until the outer wall of the inner pot 6 reaches about 70 degrees, but the first and second auxiliary heaters 26, 27 are switched on by the first and second switches I, I
Since the power supply terminals a and l) are opened by I, no heat is generated at all, and once the cooking indicator d and the heat retention indicator e are off.

Of course, when starting rice cooking as described above, the magnet 39
In order to ensure that the temperature-sensitive ferrite 36 and the magnet 39 are attracted and held, the attraction force between the temperature-sensitive ferrite 36 and the magnet 39 is set to be larger than the repulsive force of the first spring 44 and the push-down force that is the sum of the weight of the operating rod 31, magnet 39, etc. are doing.

Eventually, the temperature inside the inner pot 6 rises and the outer wall temperature of the outer pot 2 increases
At the end of cooking, when the temperature Y is around 160° and most of the moisture has been absorbed by the ink and the rice temperature Y has reached around 100°, the magnetic flux density of the temperature-sensitive ferrite 36 becomes smaller as shown in Figure 9. It becomes a weakly magnetic material and its adsorption force is weakened.
The downward force of the spring 44 overcomes the second spring 54 and pushes down the magnet 39 and the operating rod 31.

As the operating rod 31 moves downward, the movable insulator 52 moves downward under the pressure of the second spring 54, pushing down the movable contact plate 50 against its elasticity and switching the contact 48 to the other contact 47. At the same time, the mounting plate 63 also moves downward, so that the switching guide rod 65 moves rightward in the drawing by the return spring 66, and moves from the B position to the C' position in FIG. 13.

As described above, the switching guide rod 65 acts to move further to the right by the return spring 66, but due to the downward force of the first spring 44, it fits into the step C1/ at position C' and its movement is stopped.

In addition, as mentioned above, as the operating lever moves downward, the contact 48 of the first switch ■ is connected to the other contact 47, and one end of the rice cooking heater 5 is opened from one of the supply terminals and connected to the power supply. The heating of the rice cooking heater 5 is stopped after the rice is cut into one half, but since the downward movement range of the operating rod 31 is from the position B' to the position C' in FIG. Since the operation button A cannot be pressed, the common terminal 55 remains connected to one terminal 56 at the same time as rice cooking.

That is, when rice cooking is completed, the first switch ■ switches to the first and second auxiliary heaters 26 and 27, and the second switch II is connected to the rice cooking heater 5 side, and immediately enters the cooking preparation stage, and the rice cooking indicator C shows The light is turned off, and the cooking preparation indicator d is turned on once via the first switch (■) and the second auxiliary heater 27.

At this time, the heat retention indicator e connected in parallel to the second auxiliary heater 27 does not light up because the resistance value of the second auxiliary heater 27 is small.

At this time, the first auxiliary heater 26 and the second auxiliary heater 27 do not generate heat because the second switch II is not activated.

Therefore, after the above-mentioned rice cooking is completed, the temperature at the center of the bottom of the inner pot 6 becomes Z.
When the temperature rapidly decreases and reaches around 110° after a predetermined period of time, and when the outer wall temperature X of the outer pot 2 rapidly decreases and reaches around 120-130° As shown, the temperature-sensitive ferrite 36 returns to a ferromagnetic material, and the magnet 39 is attracted to the temperature-sensitive ferrite 36 against the first spring 44.

At this time, since the operating rod 31 moves upward again at the same time as the above-mentioned rice cooking starts, the movable contact plate 50 of the first switch (2) connects the contact 48 to one contact 46 due to its own elasticity, and the rice cooking heater is heated again. 5 to generate heat at 600 W to heat the inner pot 6 and turn on the rice cooking indicator C.

At this time, the cooking preparation indicator d goes out.

On the other hand, due to the upward movement of the mounting plate 63, the switching guide rod 65 further moves to the right in the switching guide groove 60, reaches the D' position from the C/ position, and is fitted into the step D// at the D' position, resulting in the current state. maintain.

As the cooking progresses as described above, the temperature of the outer wall of the outer pot 2 and the inner pot 6 rises rapidly, causing moisture on the surface of the rice to evaporate and be absorbed into the rice, completely converting the starch into d. This will make the rice fluffy and fluffy.

Eventually, when the outer wall temperature X of the outer pot 2 reaches around 160° and the bottom center temperature Z of the inner pot 6 rises to around 140°, the temperature-sensitive ferrite 36 becomes weak again as shown in FIG. The magnet 39 and the operating rod 31 are pushed down by the first spring 44, and the contact 48 of the movable contact plate 50 of the first switch (2) is connected to the other contact 47, and one supply terminal is connected to the other contact 47. are connected to the first and second auxiliary heaters 26 and 27.

The switching guide rod 65 is connected to the switching guide groove 60 before starting rice cooking.
In order to descend to step A'' at position A' of
The downward stroke of 1 becomes longer and the pressing piece 6 of the pressing fitting 67
8 presses the operation button A of the second switch II and connects the common terminal 55.
is connected to the other contact 57.

In this way, the first and second switches I and II switch and connect, so the rice cooking heater 5 enters the double-off state, stops generating heat, turns off the rice cooking indicator C, and supplies the terminals a and l.
) is connected to a heat-retaining circuit in which the second auxiliary heater 27 is connected in parallel to the series circuit of the first auxiliary heater 26 and the heat-sensitive element 23, so each of the auxiliary heaters generates heat at the beginning and enters the heat-retaining state.

Therefore, from immediately after the rice cooking is completed as described above to once the rice has been cooked (for about 15 to 20 minutes), the heat generated by the top lid heater 16 and the rice cooking heater 5 at the time of rice cooking and once cooking, and the residual heat after once cooking is completed. As shown in Figure 14 for a certain period of time, the rice temperature Y is approximately 1
It is held near 00° and unevenness is performed.

The first auxiliary heater 26 whose temperature is controlled by the heat-sensitive element 23 in the initial stage of heat retention is controlled when the heat-sensitive element 23 is OF.
F, only the second auxiliary heater 27 generates heat, heating the side of the inner pot 6, and heating the inner pot 6 from the top surface of the top cover heater 16, effectively heating the inner pot 6 with a total of 38.5 W, and the heat retention indicator e is displayed.
The lamp lights up to indicate that it is in a warm state.

Eventually, as shown in FIG. 14, the temperature of the outer wall of the outer pot 2 and the bottom center temperature Z of the inner pot 6 decrease, and the rice temperature Y decreases until the temperature of the outer wall of the outer pot 2 reaches about 70° (70°). When the heat-sensitive element 23 reaches ONL, the first auxiliary heater 26 generates heat, and the upper lid heater 16 and the second
The inner pot 6 is heated with a total of 88.5 W together with the auxiliary heater 27, and when the temperature reaches about 70° or more again, the heat-sensitive element 23 turns off.
F, the total power of the upper lid and the second auxiliary heater becomes 38.5W, and thereafter, the heat retention operation is performed by repeating 88.5W and 38.5W.

FIG. 11 is an explanatory diagram of the operation when the inner pot 6 is removed from the outer pot 2 for some reason during rice cooking shown in FIG. 8 (including the one-time cooking shown in FIG. 10) or during the one-time cooking preparation stage shown in FIG. To explain the details below, when cooking rice and once during cooking (Figures 8 and 10), the inner pot 6
When the heat sensitive element 22 is taken out, it is pushed up by the fourth spring 73 and protrudes far beyond the upper end surface of the bulging part 4, and the other side of the mounting plate 63 hits the stop piece 80 hanging down at the appropriate position of the outer pot 2. This contact prevents the switching guide rod 65 from protruding more than necessary, and the switching guide rod 65 is pulled downward and moved to the C' position of the switching guide groove 60.

Due to the upward movement of the heat sensitive body 22, the magnet 39 and the temperature sensitive ferrite 36 are forcibly separated, so the movable insulator 52, which is pressed downward by the second spring 54, contacts the contact 48 of the movable contact plate 50. is switched to the other contact 47 and the pressing metal fitting 67 comes into contact with the stopper 70 of the outer pot 2 and presses the operation button A of the second switch II to close the common terminal 55.
is switched and connected to the other contact 57.

In this way, both ends of the rice cooking heater 5 are opened by the first and second switches, and both ends are turned off.

This double-cut state of the rice-cooking heater is particularly effective in terms of safety, especially when the rice-cooking heater is exposed to the inner bottom surface of the outer pot 2, from the danger of electric shock and the like.

Further, after the above-mentioned inner pot 6 is taken out, the heat retention circuit of the first and second auxiliary heaters is formed, but in this case, each of the auxiliary heaters has a low calorific value and is provided on the outer wall of the outer pot 2. Therefore, there is nothing special to consider.

When the inner pot 6 is taken out during warming (FIG. 7), the heat sensitive element 22 moves upward as described above and the mounting plate 63 comes into contact with the stop piece 80, but the rice cooking heater 5 is already in the double cut state. There is no particular electrical change.

FIG. 12 shows a structure for preventing water from entering the heat sensitive element 22, in which an appropriate number of gaps 81 are formed at arbitrary locations between the lower edge of the bulging portion 4 and the outer pot 2, and a communication hole 82 of the outer pot 2 is formed. An annular projecting piece 83 is provided by bending the hole wall upwardly, and the communicating hole 82
An appropriate number of drain holes 84 are provided at relatively distant and low positions.

If water is accidentally spilled into the outer pot 2 while the inner pot 6 is removed, some of it will fall along the outer peripheral wall of the bulge 4 as shown in the figure, and some of it will spill onto the waterproof cover 38. Water falls along the inner peripheral wall of the bulging part 4 through the space between the end of the bulging part 4 and the hooking part 72 of the bulging part 4, and the water falling down this inner peripheral wall is formed by the annular protruding piece 83. It falls into the storage part 85 and drains into the drainage hole 84.
The water falls downward through the heat sensitive element 22 to prevent water from entering into the heat sensitive element 22.

As described above, the present invention includes an outer pot with a rice cooking heater disposed at the bottom, an inner pot that can be inserted and removed into the outer pot, and a spring supported on the outer bottom of the inner pot to apply a constant pressure. A switch is connected to each end of the rice-cooking heater, and both switches are opened when the pressure on the heat-sensitive element by the inner pot is released, so that the inner pot is the outer pot. If the rice-cooking heater is not stored in the inner pot, electricity to the rice-cooking heater will be completely stopped. Even if you touch it, electric shock accidents due to electrical leakage can be completely prevented.

[Brief explanation of the drawing]

Fig. 1 is a structural sectional view of the electric rice cooker of the present invention, Fig. 2 is an exploded perspective view of the heat sensitive element, A is a schematic explanatory diagram of the switching guide groove, and the opening is a sectional view taken along line A-B of A. , C is a sectional view taken along the CD line of A, 2 is a sectional view taken along the E-F line of A, and H is a sectional view taken along the G-H line of A.
Figure 4 is a cross-sectional view of the main part of the heat-sensitive body, Figure 5 is a characteristic diagram of temperature-sensitive ferrite, Figure 6 is an electric circuit diagram, and Figures 7 to 10 are explanatory diagrams of J-I line sectional views. The figure is an operational cross-sectional view showing each process of rice cooking - rice cooking completed (preparation for cooking once) and once cooking. Figure 11 is an explanatory diagram of the operation when the inner pot is not stowed. Figure 12 is a diagram showing the overflowing state when the inner pot is not stowed. Fig. 13 is an explanatory drawing showing each process position of the switching guide rod in the switching guide groove, Fig. 14 is an explanatory drawing showing the operating state of each part in relation to time and temperature, Fig. 15 is a thermosensitive FIG. 7 is a cross-sectional view showing another embodiment of the body. 2... Outer pot, 5... Rice cooking heater, 6
... Inner pot, 22 ... Heat sensitive element, 73 ...
... Spring, ■ ... First switch, I
I...Second switch.

Claims (1)

[Scope of utility model registration request] It consists of an outer pot with a rice cooking heater arranged at the bottom, an inner pot that can be inserted into and removed from the outer pot, and a heat sensitive body supported by a spring so as to be pressed against the outer bottom surface of the inner pot with a constant pressure, An electric rice cooker characterized in that switches are connected to both ends of the rice cooking heater, and both switches are opened when the pressure on the heat sensitive body by the inner pot is released.