JPS598092Y2 - High frequency heating device with heater - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a rotating mounting table for heated objects in a high-frequency heating device.

Conventionally, in order to heat the heated object more uniformly when heating the heated object using high frequency waves, a rotating mounting table for the heated object has been provided.

This is an attempt to irradiate the object to be heated with high frequency waves relatively evenly by rotating the object to correct the unevenness of the high frequency waves irradiated into the heating chamber.

There are two ways to drive this heated object rotating table: a motor is used as the power source, a rotating shaft is exposed at the bottom of the heating chamber, and the heated object mounting table is attached to this rotary shaft, and a motor is installed at the outside bottom of the heating chamber. There is a method in which a connected rotating body and a heated object rotation mounting table are provided corresponding to the bottom surface of the heating chamber, and the rotational force is transmitted by the magnetic coupling force of the magnets attached to the rotating body and the heated object rotation mounting table.

At this time, it is very troublesome for the user to clean the heating chamber in the former case because the rotating shaft, rollers for supporting the rotating mounting table, etc. are directly exposed at the bottom of the heating chamber.

Also, in terms of safety, if moisture is spilled inside the heating chamber, the moisture will drip outside the heating chamber at the bottom of the heating chamber and the rotating shaft seal, which will adversely affect the motor charging parts installed at the outside bottom of the heating chamber and cause electrical leakage. This is highly unreliable.

However, the latter does not have any of the above drawbacks and is a very reliable structure that is easy to clean and completely non-hazardous.

However, when magnetic coupling force is used for power transmission, there is a limit to the attractive force of the magnet, and there are various design constraints.

In other words, in order to reduce the force required for rotation, the support structure of the rotating mounting table must have rolling friction to minimize the resistance generated during rotation, and the supporting structure of the rotating mounting table has a very small coefficient of friction. In addition to having to use a resin material, a material with high heat resistance and low loss due to high frequencies had to be used, which was very restrictive.

However, recently, some models have been equipped with heaters, making the thermal conditions extremely severe, while the usage conditions have been limited when using magnetic coupling force, which is naturally easy to use and highly safe, for power transmission.

Therefore, the present invention is not restricted by usage conditions, can exhibit stable performance using low-cost materials, and can provide an easy-to-use structure.Hereinafter, one embodiment of the present invention will be described with reference to drawings. do.

FIG. 1 is a front view of a high-frequency heating device with a heater equipped with a rotating table for heating objects. Heaters 2 are installed above and below inside the heating chamber 1, and the structure of the rotating table is shown in FIG. As shown in the figure, a motor 4 for driving the rotary mounting table 3 is provided at the outer bottom of the heating chamber 1, and a hole 6 is provided at the bottom of the heating chamber for inserting the rotating shaft 5 of the motor 4 into the heating chamber. A gear 7 is provided to transmit driving force to the rotary mounting table 3.

At this time, since the rotating mounting table is unstable when the object to be heated is placed on it only by the gear 7, a supporting roller 8 is provided via a mounting fitting 9.

In such a system, if the object to be heated is a liquid such as coffee, milk, or alcohol, if the object is inadvertently blown during heating or when the user is putting it in and taking it out, it will accumulate at the bottom of the heating chamber and cause damage to the motor rotation shaft 5. Despite the presence of the sealing material 10 from the opening 6, there is a high possibility that moisture will drip onto the motor rotation bearing and charging portion, causing problems such as electrical leakage and motor rotation failure.

Moreover, the ease of cleaning, which is a major advantage of the high-frequency heating device, is greatly impaired because the roller 8, mounting bracket 9, motor rotating shaft 5, gear 7, etc. protrude from the bottom of the heating chamber.

However, on the other hand, there are devices that retain the advantages of high-frequency heating devices and are equipped with a driving force transmission structure using magnetic coupling force in order to provide a rotating mounting table to reduce uneven heating of the object to be heated.

FIG. 3 is a front view of the same, and as shown in FIG. 4, the driving force transmission structure is as shown in FIG.
A rotating body 13 is provided, and this rotating body 13 is rotated by the rotational force of a motor via a rubber belt 14 around a shaft 15 provided at the outside bottom of the heating chamber. The rotary mounting table 11 rotates while being attracted to the rotary body 13 due to the attraction force between the magnets provided on the mounting table 11.

However, the attractive force between the magnets is limited by the distance between the two magnets and the magnetic force of the magnets themselves, and the design is extremely restricted. At this time, when a load is applied to the roller 8 and the frictional resistance rapidly increases and becomes larger than the magnetic coupling force, only the rotating body 13 rotates idly and the rotating mounting table 11 stops.

Therefore, it is necessary to reduce the frictional resistance due to the load, so by changing the rotation of the roller from sliding friction to rolling friction, the frictional resistance during rotation is greatly reduced.

However, in this structure, since the roller 8 must be rotated and also revolved, a roller position regulating member 17 is required that always holds the roller at a constant pitch and is rotatable, that is, determines the orbit of the revolution of the roller.

At this time, since the heating chamber 1, the rotary mounting table 11, and the cover 18 for housing the magnet are made of metal bodies, each metal body is designed to maintain an appropriate gap.

In other words, if metal objects come into contact with each other or the gap is too small when irradiating high-frequency waves, the high-frequency electric field will concentrate.
This is because there is a danger of sparks, etc.

Therefore, conventionally, the roller position regulating member 17 and the roller 8 are made of a resin material to maintain an appropriate gap between the respective metal bodies.

At this time, the roller position regulating member 17 and the roller 8 are
Since the high frequency is used in the heating chamber, it is required that the high frequency loss is small and the heat resistance is high.

In other words, some resin materials absorb radio waves easily while others do not. When absorbing radio waves, the material itself generates heat, and when the temperature exceeds the material's heat resistance temperature, it deforms and melts.

The types of materials that have low high frequency loss and high temperature resistance as described above are limited in variety and are very expensive, making selection and design of materials very difficult.

However, recently, some devices are equipped with heaters to compensate for one of the drawbacks of high-frequency heating, which is that bread and cookies cannot be browned or baked.

When this is combined with a rotating mounting table that transmits the driving force through magnetic coupling, the temperature of the resin material mentioned above becomes extremely high (approximately 250 to 300 degrees Celsius), and in addition to the heat generated by the high frequency, the resin material is greatly affected by the heat of the heater. It fell into an unusable state.

Therefore, when the above structure is adopted, the heater 19 is installed as shown in Fig. 5 so that the resin material is not easily exposed to the heat of the heater.
is provided above the rotating mounting table 11, and a heat shield plate 20 is provided so that the rotating mounting table mechanism does not directly receive the heat of the heater 19.

With this method, the resin material of the rotary mounting table mechanism is hardly affected by the heat of the heater and can provide stable performance.

However, this method has the disadvantage that, as shown in FIG. 6, a heater unit consisting of a heater 19 and a heat shield plate 20 must be inserted into the oven during cooking, and the heater unit must be removed during high-frequency heating.

In other words, even though the mechanism was designed for ease of use, when a heater is installed, the heater unit has to be taken in and out, making it inconvenient to use.Additionally, the addition of the heat shield plate 20 increases the number of parts. Users are forced to bear the burden of increased costs.

Therefore, in the present invention, the roller position regulating member 17 and the roller 8 are arranged as shown in Fig. 7 with a structure that takes full advantage of the easy-to-use advantage of the conventional roller and eliminates the above-mentioned disadvantages even when the heater is installed. The heater 19 is installed inside the rotary mounting table rather than the magnet 12, and the rotary mounting table is reduced by the space of the roller outside the magnet, and the heater 19 is placed on the outer periphery of the rotary mounting table.
The resin parts are spaced apart to create a structure that is less susceptible to the effects of heat from the heater.

At this time, as shown in FIG.
7 is installed, the roller position regulating member 17
It was advantageous to make the heater from metal, and there was no need to consider the effects of heat when heating the heater, making it possible to create a highly reliable structure.

However, during high-frequency heating, the rotating mounting table 11 and the roller position regulating member 17 are made of metal and the gap l between them is small, and the radio waves enter the gap l and heating both to a high temperature, causing the entire rotating mounting table to become hot. It got to the point where I couldn't even touch it.

Therefore, as shown in Figure 9, if the circular roller position regulating member (a) is made into a cross shape (the opening in the figure), the electric field in the gap (l) will rotate while constantly changing its positional relationship with the rotating mounting table during high-frequency oscillation. constantly changes, eliminating the problem of localized heating.

Not only that, but since the positional relationship between the heating chamber itself, the rotary mounting table, and the roller position regulating member itself is constantly changing and rotating, it goes without saying that this arrangement itself reduces the unevenness of the radio waves in the heating chamber itself.

In other words, it has a structure that not only rotates the heated object itself to eliminate uneven heating, but also has the ability to stir radio waves.

Furthermore, compared to conventional structures, this structure is extremely inexpensive due to fewer parts, lower prices of materials used, and easier workability, making it possible to produce products that are good for users at low prices. It can be purchased and provides an extremely superior structure without problems such as abnormal heating.

[Brief explanation of the drawing]

Figure 1 is a front view of a high-frequency heating device equipped with a heater equipped with a rotary mounting table, Figure 2 is a sectional view of the rotary mounting table drive section of Figure 1, and Figure 3 is a circuit diagram that uses magnetic coupling to transmit driving force. A front view of a high-frequency heating device with a heater equipped with a transfer table, Fig. 4 is a cross-sectional view of the rotating mounting table drive part of Fig. 3, and Fig. 5 is a diagram of the high-frequency heating device of Fig. 4 when a lower heater is installed. cross section,
Figure 6 is an external view of the same essential lower heater unit, Figure 7 is an enlarged sectional view when the roller is installed inside the magnet, and Figure 8
The figure is a cross-sectional view when the roller position regulating member is made of metal.
FIG. 9A is a perspective view of the main roller position regulating member, and the opening is a perspective view showing an embodiment of the present invention. 1... Heating chamber, 2, 4... Heater,
8...Roller 11...Rotating mounting table,
12... Magnet, 13... Rotating body, 17
...Roller position regulating member.

Claims (1)

[Scope of utility model registration request] A food placing stand rotatably installed on the bottom of the heating chamber, a rotating body connected to a motor via a deceleration means for rotationally driving the food placing stand, a plurality of driving magnets provided on the rotating body, and a food placing table. means for magnetically coupling the magnets provided on the food placement table, a food placement table supporting roller is provided inside a plurality of driving magnets provided on the food placement table, and the roller position regulating member is made of metal. A high-frequency heating device with a heater, characterized by having a cross-shaped configuration.