JPS6237294B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high frequency heating device capable of measuring the weight of a heated object within a heating chamber.

In high frequency heating equipment using microwaves,
Many methods have already been proposed in which the weight of the object to be heated is detected and the heating time is calculated based on this. In particular, at the same time as placing the object to be heated in the heating chamber,
Ideally, it would be possible to detect the weight using a heated object mounting table, and various inventions and ideas have been focused on this point, but none of them have been put to practical use.

Among such conventional inventions, there are many that attempt to detect the weight of the object to be heated using a rotary mounting table (such as Japanese Patent Laid-Open No. 54-31648).

FIG. 1 is a sectional view schematically showing an example of such a conventional device. A magnetron 2 serving as a heating means is coupled to the heating chamber 1, and a rotary table 4 for rotating an object to be heated 3 is provided within the heating chamber 1. This turntable 4
is rotated by a drive shaft 7 connected to a motor 5 serving as a drive source and a gear 6. A rotating mounting plate 8 made of glass, ceramic, or the like is installed on the rotating table 4. The object to be heated 3 is placed on this rotary placing tray 8, and the drips etc. that spill out from the object 3 are placed thereon to keep the inside of the heating chamber clean. The rotating table 4 and the rotating mounting plate 8 are often constructed integrally, and in this case, they are engaged with the drive shaft 7 by a gear made of plastic.

Now, this rotary table 4 can freely move in the thrust direction of the drive shaft 7, and is supported at the bottom by a bearing 9 and a support table 10. The load sensor 11 is attached to this support base 10.
It measures the weight of the object to be heated 3 and inputs the data to the control section 12. The control unit 12 controls the magnetron 2 based on this data to perform optimal heating. Reference numeral 13 denotes a door body provided at the opening of the heating chamber so as to be openable and closable.

However, this conventional configuration has several drawbacks. In other words, the drive shaft 7 and the motor 5 which is the drive source
and the gear 6 are mechanically connected, and it is not easy to remove the rotary table 4. Therefore, it is extremely difficult to clean the bottom surface of the heating chamber 1, which tends to get dirty. Also, if water is spilled inside heating chamber 1,
This water travels along the drive shaft 7 and reaches electrical parts such as the motor 5, causing dangers such as electrical leakage and electric shock. Also, the sliding gear 6, bearing 9, support stand 1
0 and other structures are large-scale, have problems in terms of reliability, and are naturally expensive.

In view of this background, the present invention realizes a high-frequency heating device that has a simple configuration, has little radio wave leakage, and is easy to clean inside the heating chamber.

The configuration of the present invention will be explained below with reference to the drawings.

FIG. 2 is a sectional view of a heating chamber showing an embodiment of the present invention. A rotary table shaft 7 is formed on the rotary table 4,
Extending outside the heating chamber. One end of the rotary table shaft 7 is elastically supported by a leaf spring 15, and
Guided by 4. A pair of magnet pieces 17 are fixed to the rotary table 4 and the disk 16, and the disk 1
6 is connected to a motor 5 as a driving source by a gear 6 or a belt, and rotates around a chain yoke 14. At this time, the magnet pieces 17 attract each other, so
Rotating table 4 starts rotating. A load sensor is fixed to the back surface of the leaf spring 15, and inputs weight data of the object to be heated 3 to the control section 12. Based on this data, the control unit 12 determines the heating time and output of the magnetron 2, and controls the power supply to the magnetron 2 to achieve optimal heating.

FIG. 3 is a detailed view of the main parts of such a turntable. A low dielectric loss sleeve with a flange is provided between the rotary table shaft 7 and the rotary yoke 14 to ensure smooth vertical sliding of the rotary table 4 and to prevent water leakage from the heating chamber. This produces a packing effect. Sparks can also be prevented.

Furthermore, by providing the leaf spring 15 close to the cheese yoke 14, the protrusion dimension d of the rotary table shaft 7 to the outside of the heating chamber can be suppressed to a smaller value than that of the conventional example, thereby reducing the amount of radio waves leaking from the heating chamber. It can be reduced.
If a strain gauge is used as the load sensor 11, the stroke d can be set to an extremely small value. FIG. 4 shows such a strain gauge, in which a resistance foil 20 is printed on a base 19 and covered with a protective sheet 21 such as a laminate film. This strain gauge measures the weight by utilizing the fact that when the leaf spring 15 is displaced in accordance with the weight of the object to be heated, the resistance value of the resistance foil 20 changes due to its expansion and contraction.

With this configuration, the rotary table shaft 7, the motor 5 and the gear 6, and the disc 16, which are the drive sources, are mechanically separated, and the rotary table 4 can be freely attached and detached. Therefore, the bottom surface of the heating chamber, which tends to get dirty, can be easily cleaned by removing the rotary table 4. Moreover, when the rotary table 4 is removed, the leaf spring 15 that supported the rotary table shaft 7 completely blocks the opening of the cheese yoke 14, so when cleaning the heating chamber, the user may accidentally put his/her finger into the machine chamber and receive an electric shock. There is no danger of doing so. Furthermore, even if water is spilled during cleaning, it can be prevented from reaching the machine room and causing ground faults in various electrical components, creating a risk of electrical leakage or electric shock.

As described above, according to the present invention, it is possible to realize a high-frequency heating device that has a simple structure, is excellent in durability, has little radio wave leakage, and is easy to clean inside the heating chamber.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a device showing a conventional example, Fig. 2 is a cross-sectional view of a device showing an embodiment of the present invention, Fig. 3 is a detailed view of the same main part, and Fig. 4 is a strain gauge as a load sensor. be. DESCRIPTION OF SYMBOLS 1... Heating chamber, 2... Heating means, 3... Heated object, 4... Turntable, 7... Turntable shaft, 11... Load sensor, 12... Control unit, 14... Chiyoke, 16 ……disk.

Claims (1)

[Claims] 1 A heating chamber that accommodates an object to be heated, a heating means coupled to the heating chamber, a rotary table having a rotary table shaft on which the heated object is placed and rotates it, and a magnet piece that drives this rotary table. A disk arranged circumferentially, a drive source connected to the disk to rotate it, a leaf spring that elastically supports the rotary table in the thrust direction, a load sensor connected to the leaf spring, and and a control unit that measures the weight of the object to be heated using a load sensor, and the rotary table is configured to be detachable, so that when the rotary table is removed, the leaf spring closes the opening through which the rotary table shaft of the rotary table passes. A high-frequency heating device characterized by being attached to.