JP2883575B2 - rice cooker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a rice cooker using a lamp heater such as a halogen lamp heater as a heating source.

[0002]

Conventionally, electric rice cookers generally have a sheathed heater as a heating source. However, since the sheathed heater has a large self-heat capacity and takes a long time to reach a high temperature, there is a disadvantage that rice cooking time is lengthened.

In recent years, rice cookers using electromagnetic induction heating as shown in FIG. 9 have been provided. In this device, a circular container-shaped inner frame 2 made of a material that allows magnetic flux to pass therethrough, for example, a heat-resistant resin, is provided in a main body 1, and a bottom induction coil 3 is provided at the bottom of the inner frame 2.
Is provided with a side induction coil 4 in a lower peripheral portion of the. Outside the induction coils 3 and 4, a magnetic shield ferrite 5 for preventing leakage of magnetic flux is provided.

[0004] In the inner frame 2, for example, a pot 6 formed by press-forming a plate material in which a stainless material and an aluminum material are joined is accommodated, and is subjected to induction heating by the induction coils 3 and 4. As a result, the pot 6 itself generates heat and cooks rice. In such an induction heating method, advantages such as good-quality rice can be cooked with a good temperature distribution and the temperature rises quickly during heating can be obtained as compared with those using a sheathed heater.

[0005] However, in the rice cooker of the induction heating method as described above, expensive materials must be used for the pot 6, and an oscillation circuit for obtaining a high frequency is required. There is a problem that it becomes expensive.
Further, there is a disadvantage that energy loss such as copper loss occurring in the induction coils 3 and 4 is large and heating efficiency is low.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a rice cooker which has a quick rise in temperature at the start of heating, can be configured with an inexpensive structure, and has an excellent heating effect. It is in.

[0007]

The rice cooker according to the present invention has a light transmitting property in the lower opening of the inner frame having upper and lower surfaces opened in the main body.
A pot receiving part provided blocking a glass plate for the
The lower side of the glass plate is connected to the pan housing by the glass plate.
Heater housing provided in cut form, and heater
An annular lamp heater as a heat source provided in the housing part, and the reflector positioned at the bottom of the lamp heater, the
Reflector and provided integrally located inside of the lamp heater characterized by the structure comprising an inner reflector for reflecting upward the light from the lamp heater (claim 1
Invention).

[0008] According to this configuration, the pot stored in the pot storage portion is heated mainly by the heat rays from the lamp heater located below, and cooks rice. Therefore, the temperature rise at the start of heating is quick, and a configuration that is less expensive than when induction heating is employed can be achieved. At this time, the space inside the main body is divided up and down by a glass plate
Since the pot storage section and the heater storage section are provided in the state,
The top of the lamp heater is covered by a glass plate with a light-transmitting
Pots receiving through the glass plate with can be protected from mechanical external force, the light (heat rays) from the lamp heater Te
Ru can be efficiently supplied to the unit. Since the lamp heater is formed in a ring shape, a single lamp heater can strongly heat a wide area below the pot.
In addition, the reflector can reflect light emitted downward from the lamp heater to be used for heating the upper pot,
Furthermore, the inner reflector allows the heat rays emitted from the lamp heater to be directed inward to be reflected upward, and can be used for heating the central portion of the pot. As a result, the heating efficiency is excellent, and the pan is prevented from being locally heated.

[0009] In this case, since the provided one <br/> body specific to the above reflector and the inner reflector, the configuration is simplified,
The gap between the reflector and the inner reflector can be eliminated, and the inconvenience of heat rays entering the gap can be prevented.

Furthermore, at this time, the reflector and the inner reflector, may be composed of one metal plate (claim 2
Invention). According to this, the configurations of the reflector and the inner reflector can be simple and inexpensive. By integrally forming the inner reflector, the metal plate can be reinforced, and the occurrence of thermal deformation or the like can be prevented.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention (a contract
( Corresponding to claim 1 ) will be described with reference to FIGS. First, the configuration of the rice cooker 11 according to the present embodiment will be described with reference to FIGS.

FIG. 1 shows the overall configuration of a rice cooker 11, wherein the outer shell of a main body 12 is formed into a rounded rectangular container shape as a whole from an outer frame 13 and a bottom case 14. A lid 15 is rotatably provided on the upper surface of the main body 12 via a hinge 16. In the outer frame 13, an operation unit 17 having various operation keys and a display unit including an LCD is provided on a slope portion 13a from the front surface to the upper surface of the main body 12.

In the main body 12, there is provided a pan accommodating portion 19 in which a pan 18 is removably accommodated. Here, the pot 18 is made of, for example, an aluminum material and has a circular container shape with an open upper surface. The pan storage unit 19
In this case, a flat glass plate 21 is disposed on a cylindrical inner frame 20 having both upper and lower surfaces open so as to cover the bottom of the inner frame 20. When the pan 18 is stored in the pan storage unit 19, the bottom surface of the pan 18 is placed in close contact with the upper surface of the glass plate 21.

In this case, the inner frame 20 is made of an iron plate plated with an alloy having substantially the same stoichiometric ratio of zinc and aluminum, and its surface has a high light reflectance. And the inner frame 20 has an upper inner frame 20 a slightly larger in diameter than the pot 18.
And a lower inner frame 20 slightly larger in diameter than the upper inner frame 20a.
b, so that the inner diameter of the lower portion is larger than the inner diameter of the upper portion, and the lower inner peripheral portion of the inner frame 20 (lower inner frame 20b) and the lower outer peripheral portion of the pan 18 are formed. A space for reflecting light is formed between the light emitting element and the light emitting element.

The inner frame 20 is fixed to the outer frame 13 by a flange 20c provided at an upper end thereof. Further, the flange portion 20c is provided with a sealing material 22 for sealing between the outer periphery of the upper end portion of the pan 18 and the inner frame 20 when the pan 18 is stored in the pan storage portion 19. A body heater 23 for keeping rice warm is provided on the outer periphery of the upper inner frame 20a.
b, an upper temperature sensor 24 and a lower temperature sensor 25 for contacting the outer peripheral surface of the pan 18 to detect the temperature of the pan 18
Is provided.

The glass plate 21 is fixed to the flange portion 20d at the lower end of the inner frame 20.
A heater cover 27 that supports the heater unit 26 is fixed. The glass plate 21 is made of crystallized glass having high strength, high thermal shock resistance, and high permeability to heat rays, and is fixed to the flange portion 20d so as to be addressed from below. At this time, as shown in FIG. 2, a portion of the outer peripheral portion of the glass plate 21 which is addressed to the flange portion 20d has a plurality of through holes 2 serving as heat transfer resistance.
1a is formed. A ring-shaped sealing material 28 having high heat resistance is provided between the upper surface of the glass plate 21 and the inner peripheral surface of the lower end of the inner frame 20.

Now, regarding the heater unit 26,
This will be described with reference to FIGS. This heater unit 2
In this case, a halogen lamp heater 30 as a heat source is accommodated in a heat insulating material 29 having a shallow bottom circular container shape in this case. Therefore, the heat insulating material 29 is
It has a function as a data storage unit. The heat insulating material 29
Is made of a ceramic material, in which case its surface (inner surface) is finished to reflect light to some extent,
It has a function as a reflector. The heat insulating material 29 includes a bottom portion 29a and a ring-shaped peripheral wall portion 29b formed separately, and has a diameter substantially equal to that of the inner frame 20 (lower inner frame 20b).

As shown in FIG. 3, the halogen lamp heater 30 is formed in a substantially annular shape whose both ends are close to each other, corresponding to the outer peripheral portion of the bottom surface of the pot 18, and the both ends thereof are connected to the bottom portion 29a and the peripheral wall. It is supported by the heat insulating material 29 so as to be sandwiched between the portion 29b. Terminal portions 30a, 30 at both ends
a is located outside the heat insulating material 29. In this embodiment, the halogen lamp heater 30 is an AC100
A 1200 W rated voltage is used.

In this embodiment, a conical convex portion 31 as an inner reflector is integrally formed on the upper surface of the heat insulating material 29 (bottom portion 29a) at the center of the halogen lamp heater 30. Is formed. In addition, as shown in FIGS. 3 and 4, as shown in FIGS. 3 and 4, the inclination is located between both ends of the halogen lamp heater 30 and is directed toward both ends of the halogen lamp heater 30 (to the left and right in FIGS. 3 and 4). An inclined convex portion 32 having a reflective surface is formed integrally.

As shown in FIGS. 1 and 2, a heater mounting plate 33 slightly larger in diameter than the heat insulating material 29 has a slight gap (air layer) on the lower surface side of the heat insulating material 29. It is stuck to. The heater unit 26 configured as described above is supported while being accommodated in the heater cover 27.

That is, the heater cover 27 has a container shape slightly larger than the heater unit 26, and as shown in FIG. 1, three rod-shaped guide members 34 (1) provided on the lower surface of the heater mounting plate 33. (Shown only) are vertically movably inserted into holes formed in the bottom surface of the heater cover 27, and a coil spring 35 as an elastic body is provided around the outer periphery of the guide members 34. Thus, the heater unit 26 is supported in the heater cover 27 in a state of being urged upward.

The upper end of the heater cover 27 is fixed to the flange portion 20d at the lower end of the inner frame 20, so that the halogen lamp heater 30 has the heat insulating material 29 disposed below the glass plate 21. At this time, the upper end of the heater unit 26 (heat insulating material 29) is pressed against the lower surface of the glass plate 21 by the urging force of the coil spring 35. With this, the upper opening of the heat insulating material 29 is closed by the glass plate 21.
The pan is closed in the state, and the pot housing 19 and the heater housing (insulated)
Material 29) is vertically separated by a glass plate 21
It is said. Then, the lamp heater 30 is protected by the glass plate 21, and light (heat rays) from the lamp heater 30 passes through the glass plate 21 and is stored in the pan housing 19 (pan 1).
8) is directly irradiated.

A heat insulating plate 36 is provided on the lower surface side of the heater cover 27 so as to have an air layer. Also,
As shown in FIG. 1, on the front side inside the main body 12 (outer frame 13), a control unit 38 having a control unit 37 (see FIG. 5) composed of a microcomputer or the like is provided.
A code reel unit 39 for accommodating a power cord (not shown) is provided on the back side in 3). Further, a lid heater 40 is provided on the lower surface of the lid 15 to prevent dew condensation and the like.

FIG. 5 schematically shows the electrical configuration of the rice cooker 11 having the above configuration. That is, the rice cooker 11 is connected to a power supply 41 (AC100V) via a power cord,
An alternating current is supplied to the halogen lamp heater 30 via a power control element 42 such as a thyristor.

On the other hand, a setting signal by a user operating an operation key of the operation unit 17 is input to a control unit 37 composed of a microcomputer or the like, and the upper temperature sensor 2
4 and the detection signal of the lower temperature sensor 25 are
Is to be entered via In this case, boiling of water in the pot 18 is detected by the upper temperature sensor 24,
The lower temperature sensor 25 detects the setting temperature and the completion of cooking. The control section 37 performs a required display on the display section according to the control program based on the input signals, and controls the power control element 42 on and off via the phase angle variable section 44 to control the halogen lamp heater 30. The power supply to the power supply is controlled.

In this case, as will be described later in the description of the operation, the control section 37 reduces the input power to the halogen lamp heater 30 by phase control at the beginning of energization after the halogen lamp heater 30 is cold. The control is performed such that the input power is increased (100% energization) after a certain time has elapsed. In addition, DC for circuits such as the control unit 37 is used.
Power is supplied through a DC power supply unit 45. Although not shown in FIG. 5, the body heater 23 and the lid heater 40 are also controlled by the control unit 37.

Next, the operation of the above configuration will be described with reference to FIGS. For example, when the user wants to cook white rice, the user stores the pot 18 containing the required amount of rice and water in the pot storage portion 19 and operates the operation key to operate the menu (white rice, cooking, Porridge, etc.)
) And an instruction to start the rice cooking operation or reservation setting of the cooking time is performed.

Here, as shown in the flow chart of FIG. 6, when the rice cooking operation is started, the energization of the halogen lamp heater 30 is started.
Is started (step S1), and the power control element 42 is turned on by the phase control, for example, at a phase angle of 140 ° (step S2). As a result, as shown in FIG. 7, the current waveform flowing through the halogen lamp heater 30 at the beginning of the energization is (b) compared to the power supply voltage waveform (a).
The current becomes small as shown in FIG. Even with a small current, the filament of the halogen lamp heater 30 is instantly heated.

When the value of the timer T reaches a predetermined time T0 (for example, 5 ms) (Yes in step S3), the power control element 42 is turned on at a phase angle of 0 ° (step S3). S4) As shown in FIG. 7C, the halogen lamp heater 30 is energized at 100%. Thereafter, a normal rice cooking operation is performed. As a result, the rush current is suppressed, and problems such as the operation of the breaker can be prevented. The control in step S2 is performed at several Hz.
, The quick heat property is not impaired.

When the halogen lamp heater 30 is energized by 100%, the temperature of the filament exceeds 2,000 ° K.
It outputs light having a distribution with a wavelength peaking at 1000 nm in the infrared region. This light passes through the glass plate 21 and irradiates the pan 18 to heat the pan 18, and the heat generated by the halogen lamp heater 30 itself also generates heat.
Through the pot 18. Since the radiant heat due to light is transmitted to the pot 18 immediately after the start of energization, the temperature at the time of heating rises quickly.

The light from the halogen lamp heater 30 has a high reflectance in the space between the lower inner peripheral portion of the inner frame 20 and the lower outer peripheral portion of the pan 18 as shown by an arrow A in FIG. The pan 18 is reflected by the inner surface of the inner frame 20, and the pot 18 is also heated from the lower side by the radiant heat of light, and is heated so as to wrap from below. In addition, since the halogen lamp heater 30 is formed in an annular shape corresponding to the outer peripheral portion of the bottom surface of the pan 18,
As shown in FIG.
As shown by an arrow B, the convection of water in the pot 18 can be made suitable for rice cooking, such as rising from the outside and descending from the center, as in the case of cooking from a long time, and the rice is cooked deliciously. You can do it.

At this time, the halogen lamp heater 3
Since the heat insulating material 29 located at the lower portion of the heat source 29 functions as a reflector, the heat rays emitted downward from the halogen lamp heater 30 are reflected on the surface of the heat insulating material 29 and are used for heating the upper pot 18. Will be done. Moreover, the heat insulating material 2
9, the conical convex portion 31 serving as an inner reflector is integrally formed at the center of the upper surface, so that light reflected from the conical convex portion 31 (indicated by an arrow C in FIG. 2) slightly separates from the halogen lamp heater 30. The heating on the center side of the pot 18 can be supplemented. In this case, since the conical convex portion 31 is formed integrally with the heat insulating material 29 (reflector), the structure is simplified, and the heat insulating material 29 and the conical convex portion as provided separately are not only simplified. There is no gap between the gap and the gap 31, and it is possible to prevent inconvenience that a heat ray enters the gap.

Further, since the inclined convex portion 32 is formed integrally with the heat insulating material 29 at a position between both end portions of the halogen lamp heater 30, the reflected light from the inclined convex portion 32 allows the halogen lamp heater 30 to be formed. Heating in the portion between both ends can also be supplemented. In addition, the lower portion and the side of the halogen lamp heater 30 are surrounded by the heat insulating material 29, and the heat insulating material 29 is in close contact with the glass plate 21, so that the heat of the halogen lamp heater 30 can be radiated downward or to the side as much as possible. Further, since the sealing member 22 is provided between the outer periphery of the upper end portion of the pot 18 and the inner frame 20, heat can be prevented from escaping from the side of the pot 18 to the upper portion.

The heater mounting plate 33 and the heater cover 2
7. By providing the heat insulating plate 36 and the like and forming an air layer outside the heater unit 26, the heater unit 2
6, the heat shielding from below and to the side is sufficiently performed, so that the inside of the outer frame 13, the bottom case 14, and the like are not exposed to high temperatures. In addition, since the glass plate 21 is disposed at the bottom of the pan housing portion 19, when the broth or the like spills out of the pan 18, it can be easily wiped off, and the cleaning becomes extremely easy.
With the sealing material 28, there is no fear that the broth or the like leaks to the outside. The upper part of the lamp heater 30 is covered with the glass plate 21
Is likely to break when a mechanical external force is applied.
It is possible to protect the lamp heater 30
Needless to say,

As described above, according to the present embodiment, since the halogen lamp heater 30 is used as a heating source, the temperature rise at the start of heating can be accelerated, unlike the conventional case using a sheathed heater, and Time can be reduced. Further, as compared with that shown in FIG. 10 using induction heating, a complicated oscillation circuit, expensive induction coils 3, 4 and a pot 6 are not used, so that a significant cost reduction can be achieved. In addition, high heating efficiency can be obtained without copper loss or the like of the induction coils 3 and 4.

In this embodiment, since the halogen lamp heater 30 is formed in an annular shape corresponding to the outer peripheral portion of the bottom of the pan 18, a single halogen lamp heater 30 heats a wide range of the lower outer peripheral portion of the pan 18 strongly. can do. In addition, a heat insulating material 29 functioning as a reflector is provided below the halogen lamp heater 30, and a conical convex portion 32 as an inner reflector is integrally provided on the heat insulating material 29, so that the heating efficiency is sufficiently improved. Can be improved,
The heating in the central portion of the pot 18 could be supplemented, effective heating could be performed with a good temperature distribution, and it was possible to cook delicious rice.

[0037]

[0038]

[0039] Figure 8 is a second embodiment of the present invention (Claim 2
). In the heater unit 61 of the present embodiment, the annular halogen lamp heater 30
A reflector 63 as a reflector made of a single metal plate (for example, a chromium-plated stainless steel plate) is provided between the heat-insulating member 62 and the heat insulator 62 having a shallow bottom circular container shape. Then, this reflection plate 63, the inner and located in central
With conical projection 63a corresponding to the side reflector are integrally formed, it is positioned on the outer periphery Te supermarkets shaped slope portion 6
3b are integrally formed.

Also in such a configuration, the light reflected by the reflection plate 63 can further improve the heating efficiency and optimize the temperature distribution. Also, in this case,
Since the reflector and the inner reflector are formed of a single metal plate, the configuration is simple and the cost can be reduced. The reflecting plate 63 is formed by a diaphragm or the like, which can reinforce the metal plate and can prevent the occurrence of thermal deformation and the like, so-called so-called sticky sound. Can be prevented.

Although not shown, on the upper surface of the heat insulating material,
Instead of the inclined convex portions 32 in the first embodiment, a mountain-shaped reflector made of a metal plate having inclined reflective surfaces facing both ends of the halogen lamp heater 30 may be provided . It is also possible to adopt a configuration in which the upper flange portion of the pot 18 is supported by the peripheral edge of the pot storage portion 19 (the inner frame 20). The glass plate 21 may be provided with a through hole.

Further, in each of the above embodiments, the heat insulators 29, 52 and 62 are provided below the halogen lamp heater 30, but the necessary heat insulation (heat insulation) can be obtained by providing an air layer or the like. It may be configured as follows. In this case, the inside of the heater accommodating portion does not necessarily have to be a closed space, and a through hole may be formed in a part of the bottom of the heater accommodating portion. In addition, the present invention is not limited to the conical shape, and may be configured to have one or a plurality of slopes, for example, and the present invention may be appropriately modified and implemented without departing from the gist.

[0043]

As it is apparent in the foregoing description, according to the cooker of claim 1 of the present invention, as well as an annular lamp heater having a quick heating heat source, glass space in the body
Pan housing and heater housing separated by a plate
The heat ray emitted downward from the lamp heater is reflected by the reflector, and the heat ray emitted inside from the lamp heater is reflected by the inner reflector. However, it is possible to shorten the rice cooking time quickly and to achieve an inexpensive configuration, and to achieve a practical effect that the heating efficiency is excellent and local heating can be prevented.

In this case, since the reflector and the inner reflector are provided integrally, the structure is simplified, and a break between the reflector and the inner reflector can be eliminated, and a heat ray is formed in the break. Can be prevented beforehand. When further Nico, a reflector and an inner reflector,
If it is composed of a single metal plate (the rice cooker of claim 2 ), the configuration of the reflector and the inner reflector can be simplified and inexpensive, and the metal plate can be reinforced to cause thermal deformation and the like. Can be prevented beforehand.

[Brief description of the drawings]

FIG. 1 shows a first embodiment of the present invention, and is an overall vertical side view.

FIG. 2 is a longitudinal sectional side view of a main part.

FIG. 3 is a plan view of a heater unit.

FIG. 4 is a vertical sectional view of the heater unit taken along the line IV-IV in FIG. 3;

FIG. 5 is a block diagram showing an electrical configuration.

FIG. 6 is a flowchart showing a control procedure at the beginning of energization.

FIG. 7 shows a waveform of a current flowing through a halogen lamp heater.

FIG. 8 shows a heater unit according to a second embodiment of the present invention.
Longitudinal side view

FIG. 9 is a diagram corresponding to FIG. 1 showing a conventional example.

[Description of References] In the drawings, 11 is a rice cooker, 12 is a main body, 13 is an outer frame, 17
Is an operation unit, 18 is a pan, 19 is a pan accommodating portion, 20 is an inner frame, 20a is an upper inner frame, 20b is a lower inner frame, 20c, 2
0d is a flange portion, 21 is a glass plate, 21a is a through hole, 2
2 is a sealing material, 26 and 61 are heater units, 27 is a heater cover, 29 and 62 are heat insulating materials, 30 is a halogen lamp heater (lamp heater), 31 is a conical convex portion (inner reflector), 32 is The inclined convex portion, 35 is a coil spring, 37 is a control portion, 42 is a power control element , 63 is a reflector (reflector) ,
63a indicates a conical convex portion (inner reflector) .

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-3-151916 (JP, A) JP-A-55-68332 (JP, A) JP-A-4-341785 (JP, A) 93326 (JP, U) Japanese Utility Model Showa 55-4751 (JP, U) Japanese Utility Model 1-123106 (JP, U) Japanese Utility Model 3-27429 (JP, U) Japanese Utility Model 2-122634 (JP, U) (58) Field surveyed (Int. Cl. ⁶ , DB name) A47J 27/00-27/64 H05B 3/74 F24C 7/04

Claims (2)

(57) [Claims] 1. A lower surface of an inner frame having upper and lower surfaces opened in the main body.
A pot housing portion provided with the opening closed by a translucent glass plate; and a glass plate on the lower surface side of the glass plate.
Heater compartment provided in a form that is separated from the pan storage section.
A volume portion, and an annular lamp heater as a heat source provided in the heater housing portion, and a reflector located below the lamp heater, the reflector and provided integrally with and positioned inside the lamp heater And an inner reflector that reflects light from the lamp heater upward. 2. The reflector and the inner reflector are a single metal plate
The rice cooker according to claim 1, wherein the rice cooker is constituted by: