JP2000300429A - Electromagnetic induction heat type rice cooker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a lunch carriage used for lunch service in a hospital or the like capable of heating only containers required to be kept hot immediately before they are served. SOLUTION: Heating coils 9 and 10 are installed under a dish required to be kept hot (heating containers 2 and 3) among dishes placed on a tray 1, temperature detecting elements 12 and 13 for detecting temperature at a bottom surface of the heat containers 2 and 3 are embedded at the center of the heating coil 9 and 10, an opening part 1a is provided in the tray 1 under the heating containers 2 and 3, radial heat from a heat generating body 20 on a bottom surface of the heating containers 2 and 3 is detected, and the heating containers 2 and 3 are heated to a proper temperature, thereby only food in the heating containers 2 and 3 is heated to the proper temperature.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a heating device mounted on a catering service or the like used mainly in hospital lunches, nursing homes, nursing homes and the like.

[0002]

2. Description of the Related Art Most of catering catering trucks which have been conventionally used for hospital meals, etc., did not have a heating and heating function. This is because, depending on the contents of the meal, there is a mixture of foods that should be kept warm and heating and those that should not be kept warm. For example, in the case of supplying food to one patient, cooked products placed on one tray include those that require heat retention and those that do not require heat retention. In addition, it is not necessary or necessary to keep warm even when the menu changes, so it is difficult to keep warm even though it is placed on the catering car. In addition, even if a single catering car is viewed, there are cases in which meals for a number of patients are placed and cooking may be different depending on the patient. Therefore, it is not necessary or necessary to heat and heat each tray.

[0003] Further, in facilities with a large number of patients or residents, a large amount of meals are prepared, so that cooking is performed at a time considerably earlier than the time for serving meals and finished sequentially, so that cooked items are served on tableware. It is left in a state where it is placed on a catering car. As a result, foods to be eaten in a warm state often become cold, and hospital meals generally lacked in taste.

In recent years, hospitals, nursing homes, nursing homes, and other facilities that provide a large amount of lunch have been in compliance with HACCP in order to prevent food poisoning and hospital infections. In order to prevent the propagation of germs, those items that have been left for a long time from the end of cooking until they are provided to patients, etc., are placed on tableware and placed on a catering car, stored in a cart-in refrigerator and served here for lunch. And served to individuals.

[0005] In this method, since all the dishes are cooled, it is impossible to serve them to individuals as they are. Some of the cooked products that are suitable for cooling and those that need to be kept warm and heated to an appropriate temperature are mixed, so that those requiring warming and heating need to be heated for each tableware. As a method of this heating, using a catering car equipped with a low-power electric heater below the tableware that needs to be heated, put it on the tableware and put it on the catering car, and keep it cool in a cart-in refrigerator. In a certain state, the small-power heater is energized several tens of minutes before the meal supply time to heat tableware that needs to be kept warm.

[0006]

However, this method has the following problems.

When a mica heater or a sheathed heater is used as a heating source, since the heating efficiency for tableware is low, a large amount of heat is radiated to portions other than the tableware, which leads to a rise in the temperature of this portion. This causes problems such as increasing the temperature of the cooked product.

[0008] In addition, there is a problem that even cooked products that do not require heat retention are heated if the heater switch is turned on by mistake. In the case of the electric heater, when the switch is set to "ON", the heater will be heated regardless of what tableware (regardless of the material, shape and size of the container) is placed on the heater. Therefore, even if cooked products that require heat retention and cooked food are distinguished by the size of the container, etc., if the switches are not correctly turned on and off, incorrect heating may occur. There is a problem that heating cannot be performed in reverse.

In the conventional temperature detection method, a sensor is directly pressed against an object to be measured, and the sensor detects the temperature of the object to be measured by heat transfer and heat conduction. Accordingly, the sensor has a movable structure and uses a spring or the like so that the sensor can be pressed against the object to be measured with a constant load. In addition, because of the structure with movable parts, it is necessary to provide a waterproof structure when manufacturing products, or to prevent water from entering the electric and electronic circuits when water flows in, which increases manufacturing costs. However, due to the presence of the movable part, there were also troubles such as improper operation that could not be performed, and troubles such as water intrusion.

The most accurate method of controlling the temperature is to put a temperature sensor in the food in the heating vessel, detect the temperature, and perform the heating control according to the difference between the detected temperature and the set temperature. Temperature control is possible. However, there is a problem that it is not preferable from the viewpoint of hygiene to put the temperature sensor in the cooked food, and there is a problem that complicated operations such as cleaning and disinfection of the sensor after feeding are increased. Further, if the food is a liquid, it is easy to detect the temperature, but if the food is a solid, it is impossible to insert a temperature sensor into the solid to obtain the core temperature. Therefore, putting the temperature sensor in the cooking had many problems.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in order to solve the above-mentioned problems, and employs an electromagnetic induction heating system having a high heating efficiency for dishes as a heating method for dishes requiring heat retention and heating. Then, only the necessary dishes are heated.

A small power electromagnetic induction heating device is incorporated in the serving car, and the food to be heated is placed in a heating container capable of electromagnetic induction heating, and stored in a refrigerator for 30 minutes of meal time.
By operating the electromagnetic induction heating device ~ 40 minutes ago,
Only the food to be heated is kept at a suitable temperature.
Further, in the present invention, a temperature detecting element for detecting the temperature of the heating vessel is provided on the case surface at the center of the heating coil for electromagnetic induction heating, and the temperature of the heating vessel is controlled to an appropriate temperature.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention is directed to a heat-generating device in which the outer bottom surface of a ceramic or resin container is flattened, a small ring-shaped projection is formed on the outer periphery, and heat is generated inside the small projection by electromagnetic induction heating. A heating container is constructed by attaching a body. The heating container is placed on a tray having an opening at a portion corresponding to the bottom surface of the heating container, and is heated by a heating coil mounted in a non-metal case provided below the opening. In addition, a radiant heat from the bottom of the heating vessel is detected by a temperature detecting element embedded in the case surface at the center of the heating coil, and the signal is used to drive the electromagnetic induction heating device to control the heating so that the cooked food in the heating vessel is kept at an appropriate temperature. It is to keep warm and heat.

According to the above configuration, since the bottom surface temperature of each heating vessel is detected and the heating control is performed for each heating vessel, it is set even if a large or small fluctuation occurs in the amount of the cooked product as the load. It is kept warm to the temperature.

In the conventional electric heating method, the heating efficiency is about 65%, but in the induction heating method, a heating efficiency of 80% or more is obtained, so that the amount of electric power supplied per serving car is reduced. This is to reduce the amount of power supply for raising the room temperature in the refrigerator.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below in detail with reference to FIGS.

FIG. 1 is a top view of tableware, spoons and the like placed on a feeding tray, and FIG.
It is principal part sectional drawing of the electromagnetic induction heating apparatus including -A sectional drawing. FIG. 3 is a cross-sectional view of the heating container and the heating device, and FIG. 4 is a schematic structural diagram of a catering / delivery car equipped with the electromagnetic induction heating device of the present invention.

In FIG. 1, reference numeral 1 denotes a tray for placing tableware and the like on each person at the time of lunch in a hospital or a nursing home.
Reference numerals 2 and 3 denote tableware for holding food, and a heat-generating material (heat-generating element 2) for generating heat corresponding to induction heating described later.
0) is an induction heating-compatible container (hereinafter referred to as a heating container) mounted on the outer bottom surface of the tableware. Reference numerals 4 to 7 denote general containers that do not generate heat by induction heating. Therefore, the cooked foods that require heat retention and heating are placed in the heating containers 2 and 3, and the foods that do not require heat retention and heating are placed in the general containers 4 to 7. 8 is a spoon.

In FIG. 2, reference numerals 9 and 10 denote heating vessels 2 and 3
And a high-frequency induction heating coil for induction heating disposed under the pair. An opening 1a substantially equivalent to the heating surface is provided in a portion of the tray 1 corresponding to the heating element 20 of the heating containers 2, 3. Reference numeral 11 denotes a case which covers the heating coils 9 and 10, which is made of a non-metallic material having heat resistance and insulation properties, and is disposed below the tray 1. 1
Reference numerals 2 and 13 denote temperature detecting elements mounted on the same plane as the surface of the case 11 and at the center of each of the heating coils 9 and 10.
The temperature of the bottom surface is detected by radiant heat emitted from the bottom surfaces of the heating vessels 2 and 3. The temperature detecting elements 12, 1
3 is fixedly mounted on the surface of the case 11, and the mounting portion has a waterproof structure with a packing, a sealing material, an adhesive, or the like in order to prevent invasion of water and the like.

Reference numeral 14 denotes a wall surface of a serving car into which the tray 1 is inserted. Reference numeral 15 denotes a shelf (tray tray) protruding from both sides of the wall surface 14, which supports the tray 1 on which the dishes 2 to 8 are placed from below the left and right sides, and removes and inserts the tray 1 from the front. It has a positioning (not shown) for facilitating (setting). Reference numeral 16 denotes a box disposed between the wall surfaces 14 on both sides.
And the inside is a space.

Reference numeral 17 denotes an inverter control unit mounted on the outside of the wall surface 14, and supplies a high-frequency current to the heating coils 9, 10 according to signals from the temperature detecting elements 12, 13. An inverter control unit 17 is provided in the space inside the box 16.
And a cable 18 for connecting the heating coils 9 and 10 and the temperature detecting elements 12 and 13.

Next, details of the heating vessels 2 and 3 will be described with reference to FIG. The heating containers 2 and 3 are made of pottery or resin, and the outer bottom surface of the container is finished in a planar shape, and a small ring-shaped projection 19 is formed on the outer peripheral portion. A heating element (for example, a metal foil) 20 that generates heat in response to electromagnetic induction heating is closely attached to the inside of the small ring-shaped projection 19 by transfer or the like.

Since the ring-shaped small projections are formed on the bottom surfaces of the heating vessels 2 and 3 as described above, when the heating vessels 2 and 3 are placed on the tray 1 or the table, the heating element 20 may not hit the tray 1 or the table. There is no damage to the heating element 20 because there is no heating element.

FIG. 4 shows that the electromagnetic induction heating device of the present invention is mounted on a catering / delivery car which places a number of trays 1 on a number of shelves 15 and places a plurality of dishes on the trays 1 to provide meals. It shows the state.

Reference numeral 21 denotes a serving car. Reference numeral 22 denotes a power supply supplied from the outside of the serving car 21. Power is supplied to each inverter control section 17 via a main control section 23 having a timer or a main switch (not shown). Supplied. Reference numeral 24 denotes a power cable, and reference numeral 25 denotes a caster attached to a lower portion of the serving truck 21. Other configurations are shown in FIGS.
Since the explanation has been made in FIG. 3, the explanation is omitted.

Next, the operation of this embodiment having the above configuration will be described. When cooking items cooked in the kitchen are served in each container, cook items that require heat insulation and heating are placed in heating containers 2 and 3, and cook products that do not require heat insulation and heating are placed in general containers 4 to 7 and placed in tray 1. It is placed and further stored in a plurality of shelves 15 provided on the serving car 21. In general, work such as serving is performed much earlier than the meal serving time. And refrigerated.

In this state, since all the cooked products are kept in a refrigerated state, only cooked foods (cooked foods arranged in the heating containers 2 and 3) which need to be kept warm for several tens of minutes before meals are provided. It needs to be heated. Therefore, the timer 22 or the main switch in the main control unit 23 is operated several tens of minutes before the meal providing time, and the power supply 22 supplied from the outside of the catering car is operated.
Is supplied to each inverter control unit 17 through the power cable 24.

As a result, the inverter control section 17 is operated, and the temperature detecting elements 12 and 13 detect the radiant heat temperature from the bottom surfaces of the heating vessels 2 and 3 (the mounting surface of the heating element 20), and this portion reaches a predetermined temperature. If not reached, a high-frequency current is supplied to the heating coils 9 and 10. As a result, lines of magnetic force are generated in the heating coils 9 and 10 and the heating element 20, and an eddy current is generated around the lines of magnetic force in the heating element 20, and
Flow inside. When the current flows, Joule heat is generated, and the heating element 20 generates heat.

The generated heat is transferred to the heating vessels 2 and 3 by conduction.
Warm and heat the whole. Therefore, the temperature of the heating container 2,
Heat is transferred from the inner surface of 3 and the cooked product is heated. In the initial state of the start of energization, the cooked product and the heating containers 2 and 3 are both cooled, so that the heat generated in the heating element 20 is absorbed by the cooking product and the heating containers 2 and 3 and the temperature of the heating element 20 is also predetermined. Does not reach the temperature of Therefore, the high-frequency current is continuously supplied to the heating coils 9 and 10, and the heating state continues.

Thereafter, when the temperatures of the cooked product and the heating containers 2 and 3 themselves rise to some extent, the transfer of heat from the high temperature portion of the heating element 20 to the upper portions of the heating containers 2 and 3 and the cooked food decreases.
Then, the temperatures of the heating element 20 and the bottom surfaces of the heating containers 2 and 3 rise. This temperature rise is detected by the temperature detecting elements 12 and 13 mounted at positions opposite to the heating element 20 and a signal is sent to the inverter control unit 17. When it is detected that the temperature of this portion has risen to a predetermined temperature, the operation of the inverter control unit 17 stops or reduces the supply of the high-frequency current to the heating coils 9 and 10, thereby stopping the heat generation of the heating element 20. Or decrease it. When this state is continued and the temperature detecting elements 12 and 13 detect a predetermined temperature or lower, a high-frequency current is supplied to the heating coils 9 and 10 again, and heating is started as described above. This operation is repeated so that the temperature of the heating vessels 2 and 3 is kept constant,
The food in 3 is kept at an appropriate temperature.

In the large refrigerator, only the bottom surfaces of the heating vessels 2 and 3 generate heat, and the cooking products can be efficiently heated since they are located very close to the cooking products. Therefore, no extra heat is input into the refrigerator. At the time of serving meals, the timer or main switch in the main control unit 23 is operated to stop energizing each inverter control unit 17, and then the external power supply 22 is disconnected, and the serving truck 21 with casters 25 is placed near each hospital room. It is intended to provide a meal that is moved and kept at a suitable temperature.

[0032]

As described above, according to the present invention, a serving car used for hospital meals and the like is provided with an electromagnetic induction heating device for heating and heating a plurality of dishes at the same time. It has many advantages shown.

Of the provided meal menus, only those requiring heating and heating can be provided to the patient while being kept at an appropriate temperature, and delicious meals can be provided.

When the heating device is operated immediately before providing food for refrigerated stored food products kept in good hygiene,
Detecting the bottom surface temperature of the heating container and performing heating control to maintain the temperature of each container in which cooking products enter at a predetermined temperature, the type (liquid, solid) and quantity of cooking products entering the heating container Irrespective of this, it is possible to provide a delicious meal that is kept warm and heated to a predetermined appropriate temperature.

The temperature control element is embedded in the case at the center of the heating coil to detect the radiant heat emitted from the bottom surface of the heating container, which is at a high temperature. Is going. Therefore, even if the bottom surface of the container has some irregularities, the temperature can be controlled, and a container in which a heating element is closely attached to the bottom of a ceramic tableware can be used.

Further, since the waterproof structure can be obtained by fixing the temperature detecting element, there is no trouble of water intrusion. Further, by fixing the temperature detecting element, there is no movable part, and no components such as springs are required, the structure is simple, the manufacturing cost can be reduced, and the malfunction due to the movement is eliminated. In addition, since the mounting of the temperature detecting element is flush with the upper surface of the non-metallic case housing the heating coil, the cleaning property of the case is good,
Since the element is not convex, an accident such as damage to the element by hitting something on the element is eliminated.

By using an inverter heating method with high heating efficiency and directly heating the tableware (heating container), heat radiation to the serving car side is extremely small as compared with a conventional heating element (a heater method such as a nichrome wire). Become. Therefore, there is an advantage that the amount of power supply to one serving car is reduced, energy saving is achieved, and the rise in room temperature in the refrigerator is also reduced.

[Brief description of the drawings]

FIG. 1 is a plan view of tableware placed on a lunch tray used in a lunch delivery car.

FIG. 2 is a cross-sectional view of a main part of the electromagnetic induction heating device including the cross-sectional view along AA in FIG.

FIG. 3 is a detailed sectional view of a heating container and the like used in the electromagnetic induction heating device of the present invention.

FIG. 4 is a structural diagram of a catering and serving vehicle equipped with the electromagnetic induction heating device of the present invention.

[Explanation of symbols]

2, 3: heating container, 9, 10: heating coil, 11:
Cases 12, 13: Temperature detecting element, 19: Small ring-shaped protrusion, 20: Heating element.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3K051 AB03 AB04 AC33 AD29 AD38 CD43 CD45 4B055 AA09 AA17 BA34 BA36 BA51 BA62 CA02 CA64 CA76 CB27 CC52 CC59 CD02 DA02 DB14 DB21 EA04 EA08 FA01 FA02 FB23 FC05 FC11

Claims (2)

[Claims] A heating element that generates heat by induction heating is attached to the bottom of a heating container formed of a nonmetallic material, and a nonmetallic case is provided below the heating container and with a gap with the heating container. A heating coil for induction heating the heating element is mounted in the case, and a temperature detecting element for detecting the temperature of the bottom of the heating vessel is fixedly provided on the surface of the case at the center of the heating coil. An electromagnetic induction heating apparatus characterized in that radiant heat from a heating surface on the bottom surface of the heating vessel is detected, and based on the detected value, the heating vessel can be heated and kept at an appropriate temperature. 2. A heating vessel made of pottery or resin, finishing the outer bottom surface in a flat shape, forming a small ring-shaped protrusion on the outer peripheral portion, and generating heat by electromagnetic induction heating inside the small ring-shaped protrusion. 2. The device according to claim 1, wherein
An electromagnetic induction heating device as described.