JPH0425446B2 - - Google Patents

Description

Detailed Description of the Invention: Industrial Application Field The present invention measures the weight of the object to be heated and controls the heating time, heating temperature, heating output, heating method, etc. according to the weight, thereby achieving automatic heating. The present invention relates to a weight detection device for a heating device that makes it possible to.

Conventional technology For example, in conventional manual type high-frequency heating devices, when reheating cold rice, miso soup, etc., cooking vegetables, or thawing frozen foods, the user measures the weight of the food and calculates the weight. It was necessary to set the heating time and heating output according to the time using a time switch or output selection button. Therefore, it is necessary to perform cumbersome operations such as measuring the weight of the food, setting the heating time, and heating output before starting cooking, and it has been desired to improve the usability.

In addition, high-frequency heating devices with automatic control functions are equipped with sensors, which have been developed in recent years, to detect the surface temperature of food and the water vapor generated from food.
It detects alcohol, etc. and automatically controls food heating time and heating output. However, among these automatic heating devices, those equipped with infrared sensors that detect the surface temperature of food mainly only detect the surface temperature of a part of the food, but cannot detect the internal temperature or heating state. However, the finish was uneven depending on the shape and weight. On the other hand, products equipped with gas sensors that detect water vapor, alcohol, etc. generated from food can detect good results when reheating or cooking raw vegetables such as vegetables. Foods that do not generate steam cannot be detected, so as with the manual type, it is time-consuming to measure the weight of the food to be thawed, select the timer volume and output selection key, and then start cooking.

Therefore, in order to eliminate these shortcomings and to ensure good heating without failure, there was a desire for a device that could automatically measure the weight of food and cook with the optimal heating time, heating output, and heating method. .

In order to satisfy these demands, various methods for automatically measuring the weight of food have been devised, and some of these methods have been commercialized. However, when measuring the weight of food, the accuracy of the measuring device is required. Accuracy includes differences from true values, variations due to repeated measurements, variations caused by the position of food, variations caused by where the main body is placed, and errors caused by the environment such as temperature and humidity.

Naturally, when cooking is performed using values that include such variations and errors, the finished state of the cooked food will not be good.

Therefore, there is a need for a method and structure that can solve these problems and improve the accuracy of food weight measurements and reduce errors.

In the conventional high-frequency heating apparatus shown in FIGS. 2 to 6, for example, in FIG. 2, reference numeral 1 denotes a heating chamber in which food is stored and heated, and a door 2 is provided in front of the heating chamber so as to be openable and closable. 3 is a magnetron that supplies high frequency waves to the heating chamber 1. The high frequency waves oscillated from the magnetron 3 pass through a waveguide 4 and are irradiated onto the object to be heated 6 placed on a rotating plate 5 in the heating chamber 1, thereby heating it. do. The rotating plate 5 is placed on a rotating mounting table 7. The rotary mounting table 7 is fitted with a shaft 8 passing through an opening provided in the bottom of the heating chamber 1, and the drive of the motor 9 is transmitted to the shaft 8 by two gears 10, 11, and the rotary mounting table 7 is rotated. It's rotating.

FIG. 3 is a detailed view of the Roberval mechanism, which is a weight detection device, and FIG. 4 is a diagram showing the mechanical parts thereof. Next, details of the weight detection device will be explained with reference to FIGS. 3 and 4.

The Roberval mechanism has two aluminum blocks A12 and B13 connected by a plurality of leaf springs 14. The overlapping surfaces of the aluminum block B13 and the leaf spring 14 are fixed by a presser plate 15, and the overlapping surfaces of the aluminum block A12 and the leaf spring 14 are fixed by a magnet mounting plate 16 and a motor mounting plate 17.

A magnet 18 is fixed to the tip of the magnet mounting plate 16, and a coil 19 is fixed to the aluminum block B13.
is fixed, and the weight is detected by this magnet 18 and coil 19.

Further, a drive motor 21 for rotating a rotary shaft 20 is fixed to the motor mounting plate 17 with screws 22, and a gear A24 is fitted to a shaft 23 of the motor 21. A gear B25 is fitted onto the rotating shaft 20, and is housed in a notch in the center of the aluminum block A12. In addition, the rotating shaft 20 is connected to a hole provided in the aluminum block A12 and a bearing 3.
2 prevents wobbling in the front, back, left and right directions.

The rotation of the drive motor 21 is controlled by the gear A24,
It is transmitted to the rotating shaft 20 via the gear B25. Further, a rotating mounting table 27 on which a rotating plate 26 is mounted is fitted to the rotating shaft 20, so that the object to be heated 28 is rotated during high frequency heating so that it is heated evenly.

FIG. 5 is a sectional view showing the mounting structure of the Roberval mechanism. In the figure, 13 is an aluminum block B on the fixed end side of the Roberval mechanism, and 30 is its mounting plate.

The aluminum block B13 is attached to a strong metal mounting plate 30 fixed to the bottom of the heating chamber 29 with screws 31 to fix one end of the roberval mechanism, and vibrate the other end to which the rotating shaft 20 is attached.

Further, the aluminum block B13 has a convex shape, and the mounting plate 30 has a square shape, and is fixed at both ends of this convex shape.

In the high-frequency heating device configured as described above, when the object to be heated 28 is placed on the rotating plate 26, its weight is applied to the free end of the Roberval mechanism via the rotating mounting table 27 and the rotating shaft 20, and the weight is applied to the free end of the Roberval mechanism according to the weight. and is displaced downward. This movement is a characteristic of the Roberval mechanism and is always a vertical displacement. When the Roberval mechanism is vibrated by the impact when the object to be heated 28 is placed on it or by the impact subsequently applied to the Roberval mechanism from the outside, it vibrates at a natural frequency corresponding to its weight. Due to this vibration, the magnet 18 fixed to the free end
An induced voltage is generated in the coil 19 fixed to the fixed end, and by detecting it, the entire weight can be measured. Therefore, the rotating plate 26, the rotating mounting table 27, the motor 21, the gears 24, 25,
If the weight of the aluminum block A is measured in advance, the weight of only the object to be heated 28 can be measured from the total weight.

If the oscillation of the magnetron is controlled according to the weight of the object to be heated 28, cooking can be performed with optimum heating output and heating time.

Problems to be Solved by the Invention However, in such a structure in which the weight is measured by vibrating the Roberval mechanism, as shown in the plan view of the weight detection section in FIG. 6, the electric wire 33 connected to the drive motor 21 is It is covered with a protective tube 34. This protective tube 34 is provided to protect the electric wire 33 from metal edges and high temperature parts. In general, the material of the covering of the electric wire 33 having such a structure is often made of vinyl chloride, and the material of the protective tube 34 is often a silicon-impregnated glass braided tube.

Since the Roberval mechanism has a structure in which the block B13 is fixed and the drive motor 21 side vibrates, the electric wire 3
3 and the protective tube 34 are pulled out to the block B13 side so that they do not interfere with vibration. The electric wire 33 and the protective tube 34 are held at two locations: a protruding crimp portion 17a of the intermediate motor mounting plate 17 and a holder 36 fixed to the end of the block B13 with screws 35.

Thereby, the electric wire 33 does not come into contact with the edges of the metal parts of the leaf spring 14 or the motor mounting plate 17, or the edges of the metal parts or high-temperature parts of the main body of the periphery of the Roberval mechanism, so safety can be ensured.

However, since the electric wire 33 and the protective tube 34 each have their own inherent bending strength, both act as resistance to the vibrations of the Roberval mechanism.

In particular, since the material of the covering of the electric wire 33 is PVC, it becomes hard as the temperature drops. If left for a long time, the plasticizer deteriorates and becomes hard. Improving heat resistance will make it harder due to the effects of additives, and the coating will also become thicker, making it even harder. It had such characteristics.

In addition, when the electric wire 33 and the protective tube 34 were strongly pulled between the crimping part 17a of the holding part and the holder 36, the vibrations tended to be damped quickly.

Figure 7a shows the induced voltage generated in the coil 19 at this time, but as the vibration decays quickly, the effective number of pulses decreases, and the number of pulses originally required to measure the weight of the heated object becomes smaller. In this case, cooking may not be possible, or the accuracy may deteriorate, making it impossible to obtain optimal heating conditions.

Furthermore, in order to prevent abnormal tension from being applied to the electric wire 33 and the protective tube 34, there is a limit to how much care is taken when assembling the Roberval mechanism or incorporating it into the device body, and there is always a margin for the required number of pulses. The problem was that it was very difficult to obtain a certain number of effective pulses.

The present invention solves these conventional problems, and uses a simple configuration to always accurately measure the weight of the object to be heated, and automatically sets the optimal heating output and heating time to achieve good results. Allows for heating,
The purpose is to provide a heating device that is easy to use, convenient, and highly reliable.

Means for Solving the Problems In order to achieve the above object, the heating device of the present invention measures the weight of the object to be heated and automatically heats it with the optimum heating output and heating time. This heating device is configured to measure the weight of the heated object by the number of pulses per hour, and by removing the influence of the protective tube of the drive motor's electric wire, which was an obstacle to the vibration of the Roberval mechanism, it becomes the basic data for weight calculation. This configuration increases the number of effective pulses and ensures a stable state with sufficient margin for the required number of pulses.

Effect The heating device of the present invention has a sufficient margin in the number of effective pulses required for calculating the weight of the object to be heated, so the accuracy of measurement values is improved and the number of effective pulses is The phenomenon of inability to measure due to shortages will also disappear. In addition, the effect of the installation location of the heating device, that is, when it is installed in an unstable place such as on top of a kitchen sink, the number of effective pulses decreases and becomes impossible to measure, but this problem can also be solved.

As described above, since all the problems caused by the lack of effective pulses can be solved, stable automatic cooking can be ensured, and the reliability of the heating device can be further improved.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the drawings. In the description of the conventional example and the embodiment of the invention, the same number indicates the same name.

As shown in the plan view of the Roberval mechanism for measuring the weight of the object to be heated in FIG. 1, the rotating shaft 20 that fits into the rotating mounting table is rotated by the rotation of the drive motor 21 being transmitted through the gear A 24 and the gear B 25. do. This drive motor 21 is fixed with screws 22 to a motor mounting plate 17 that is integrated with a roberval mechanism whose basic structure is four leaf springs 14 and a pair of aluminum blocks A12 and B13. The aluminum block B13 is the fixed side of the rollover mechanism, and a magnet 18 is fixed to the free end side, and a coil 19 for detecting the amount of displacement of the magnet 18 is fixed to the aluminum block B13.

On the other hand, the electric wire 33 of the drive motor 21 is held at two locations near both ends of the leaf spring 14. On the movable side, attach the motor mounting plate 1 with the screw 35 using the holder 36.
7, the fixed side is fixed to the aluminum block B13 by a screw 37 using a holder 38. Between the motor 21 and the holder 36, the electric wire 33 is covered with a protective tube 34 and protected from the metal edge portion of the motor mounting plate 17. Between the two holders 36 and 38, only the electric wire 33 is held substantially parallel to the leaf spring 13 and without touching the leaf spring 13.

In this embodiment, the material for covering the electric wire 33 is silicone rubber, and the protective tube 34 is a silicone-impregnated silicone rubber tube.

Effects of the Invention As described above, according to the heating device of the present invention, the following effects can be obtained.

(1) With respect to the vibration of the Roberval mechanism, the influence of the protective tube of the drive motor, which was a factor that hinders the vibration, can be completely removed, and the influence of the electric wire can also be significantly reduced. This is because the silicone rubber-based covering material has much lower bending strength and hardness than conventional PVC-based materials, so it is less likely to resist the vibrations of the Roberval mechanism.

In this situation, as shown in FIG. 7b, the number of effective pulses has increased compared to the number of pulses required for weight measurement, and a sufficient margin has been obtained. As a result, the conventional phenomenon of inability to measure due to insufficient pulses is eliminated, and reliability is greatly improved.

(2) Eliminates the drawbacks of conventional PVC-based covered wires,
It does not harden even when the room temperature gets low. It will not become hard even after long-term use. It has better heat resistance than PVC. This provides the following benefits: environmental resistance of the heating device, durability for long-term use,
Safety etc. will be improved.

(3) Conventionally, when assembling the Roberval mechanism or assembling it into the device body, the tension of the wire changed and there was still a problem due to insufficient number of pulses, but the increase in the number of effective pulses increases the margin and makes it easier to perform such work. The effect disappears.

(4) The effective number of pulses tends to decrease when the heating device is placed in an unstable or soft location, but even in such cases, the influence of the increased margin for the required number of pulses is reduced. becomes difficult to receive.

(5) As mentioned above, all the problems caused by not being able to maintain a sufficient margin in the number of effective pulses can be solved, and stable weight measurement results can always be obtained.
In addition, measurement accuracy can be further improved, so the performance of automatic heating, which measures the weight of the object to be heated and automatically sets the heating output and heating time, is improved, and the finished product can be made in a better condition.

(6) In the explanation of this example, silicone rubber-based material was used for the wire sheathing, but basically the disadvantages of PVC-based material include a decrease in temperature, changes over time, and hardness and bending due to improved heat resistance. It goes without saying that the same effects as those of this embodiment can be obtained if there is no increase in strength.

[Brief explanation of drawings]

Fig. 1 is a plan view of the weight detection section of a heating device that is an embodiment of the present invention, Fig. 2 is a partial sectional view showing the structure of a conventional heating device, and Fig. 3 is a weight detection section of the heating device. 4 is an exploded view of the heating device, FIG. 5 is a partial sectional view showing the mounting structure of the weight detection portion of the heating device, and FIG. 6 is the weight detection portion of the heating device. FIG. 7 is a characteristic diagram showing signals generated in the weight detector. 12... Aluminum block A, 13... Aluminum block B, 14... Leaf spring, 18... Magnet, 19
...Detection coil, 20... Rotating shaft, 21... Drive motor, 26... Rotating plate, 27... Rotating mounting table,
28...Heated object, 33...Electric wire, 36...Holder, 38...Holder.

Claims (1)

[Scope of Claims] 1. A heating chamber in which an object to be heated is heated and cooked by a heating means, a rotating mounting table on which the object to be heated is placed in the heating chamber, a motor for driving the rotating mounting table, and a motor for driving the rotating mounting table. A mounting base, an elastic body that integrally supports the motor, a detector that detects vibrations of the elastic body, and a control device that controls a heating means, and the elastic body has a Roberval mechanism made of a plurality of leaf springs. The weight of the object to be heated on the rotating table is detected by a detector, and the operation of the heating device is controlled by the output of this detector, and the electric wire connected to the motor is connected to both ends of the leaf spring. A heating device configured to be held near the section. 2. The heating device according to claim 1, wherein the electric wire of the motor is coated with a material other than vinyl chloride.