JPH0322874Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to an improvement of a high-frequency heating device in which a rotating plate on which an object to be heated is placed is rotated using a roller rotating table.

[Technical background of the invention and its problems]

2. Description of the Related Art In high-frequency heating devices such as microwave ovens, a rotating plate is provided in a heating chamber to efficiently and uniformly heat an object to be heated.

Conventionally, such high-frequency heating devices have a transmission shaft connected to the output shaft of the drive section on the bottom of the heating chamber, and a plurality of rollers are rotatably fixed around the transmission shaft. In addition to placing the rotating plate across the upper part, a structure is used in which the tip of the transmission shaft engages with the bottom surface of the rotating plate.The transmission shaft transmits the rotation of the drive unit to the rotating plate, and each roller is connected to the support part. It is used to rotate a rotating plate.

However, with this structure in which the roller is fixed to the bottom of the heating chamber, the roller cannot be removed from the bottom of the heating chamber, so when cleaning the bottom of the heating chamber, the roller and the roller support plate that supports the roller may be damaged. It has a big drawback that it gets in the way and makes it impossible to thoroughly clean every corner.

Therefore, in order to solve this problem, a roller rotating table that rotatably supports multiple rollers is removably interposed between the rotating plate and the bottom of the heating chamber, and the roller rotating table is driven to rotate. , a system has been proposed in which a rotating plate is rotated using rollers that roll at that time.

As shown in FIG. 5, this has a stand part a in the center, and a plurality of rollers c around the stand part a that roll on the bottom surface of the heating chamber b around the center of the stand part a.
It employs a roller turntable d equipped with..., and in detail, the center back side of the stand a of the roller turntable d is connected to the output shaft of the motor (drive unit) e placed on the bottom of the heating chamber b. A rotating plate h having a recess m in the center of the back surface extends over the roller rotating table d, and each roller c... is disposed in a rotatable manner on the bottom surface around the output shaft g. Place it in the recess m of the rotary plate h.
is rotatably engaged with a convex portion n provided at the center of the surface of the roller rotating table d, and each roller c, which rolls along the circumferential direction around the output shaft g, moves the rotating plate h to the roller rotating table. The rotation is made twice as much as d. According to this, since the rotary plate h and the roller rotary table d are removable, cleaning efficiency is greatly improved.

By the way, in a high-frequency heating device employing such a roller rotating table d, since the metal output shaft g of the motor e protrudes into the heating chamber b from the bottom surface of the heating chamber b, this output shaft g is caused by a so-called antenna effect. It induces radio waves, and the radio waves may leak through this output shaft g. As a countermeasure to this, the bearing part i of the motor e and the lower surface of the bottom wall of the heating chamber b are connected to the ground by a grounding plate j to prevent radio waves from leaking through the output shaft g. For example, for a long timer,
If a cam and a switch (both not shown) for weak output were to be installed on the output shaft side of the motor e, there would be no space to install a ground plate j to prevent radio wave leakage, which would make it extremely difficult to suppress radio wave leakage. It has In addition, in a high-frequency heating device that employs such a roller rotating table d, when the roller rotating table d is set and the rotating plate h is set, the engaging part provided on the back surface of the rotating plate h, and the recess m on the back surface of the rotating plate h. Since it is difficult to see, it is difficult to set the engaging part and the recess m to the output shaft g and the convex part m without particular care, which makes the setting work very difficult. Therefore, with the roller turntable d, sparks (during microwave oscillation) are generated due to incorrect installation, electric fields are concentrated, and the surface of the roller turntable d may be damaged due to forceful setting. There is a risk that the rotating plate h may be damaged or damaged due to deformation of the roller rotating table d, and the rotating plate h may be broken or damaged due to forceful setting. There is. In addition, the roller rotating table d, which has a convex part m and an engaging part necessary for engagement on the front or back surface of the base part a, has a complicated structure due to the provision of the convex part m and the engaging part. However, there is a need for something that can improve this problem.

[Purpose of invention]

This idea was devised in view of the above circumstances, and its purpose is to suppress radio wave leakage while securing space around the output shaft without requiring a ground plate, and to suppress the leakage of radio waves. It is an object of the present invention to provide a high-frequency heating device in which a roller rotary table and a rotary plate can be easily set while simplifying the structure of the rotary table.

[Summary of the idea]

That is, in this invention, a dielectric transmission shaft having a head with a non-circular cross section is rotatably provided on the bottom of the heating chamber, and this is detachably connected to the output shaft of the drive unit, and the base of the roller rotation table is connected to the output shaft of the drive unit. A fitting hole corresponding to the cross section of the head of the transmission shaft is drilled in the center of the section, so that the roller rotating table can be placed on the bottom of the heating chamber with the head of the transmission shaft penetrating through the fitting hole. In addition, by providing a sloped part at the tip of the transmission shaft that slopes downward from the center toward the periphery, the transmission shaft installed at the bottom of the heating chamber suppresses radio wave leakage caused by the output shaft and improves transmission. The head of the shaft is also used as a convex part that rotatably supports a conventional rotating plate, eliminating the protruding part for supporting the rotating plate from the roller rotating table, and the slope of the head allows the roller rotating table and The purpose is to allow the rotating plate to be set smoothly and easily.

[Example of idea]

This invention will be explained below based on an embodiment shown in FIGS. 1 to 4. Figure 3 shows the external appearance of a high-frequency heating device, for example a microwave oven, where 1 is the main body, 2 is a heating chamber provided within the main body 1, and 3 is provided on the front side of the main body 1 to open and close the opening of the heating chamber 2. A side-opening door 4 is an operation panel provided on the front side of the main body 1 adjacent to the door 3.
On the operation panel 4, from the upper side, there is a transparent window 5a and a typical cooking menu provided on the back side of the transparent window 5a. ) is written on each of the four sides by category, a menu display section 5 consisting of a four-sided rotating menu drum 5b, an operating section 6 for rotating the four-sided rotating menu drum 5b, a cooking time setting switch 7, and a cooking start switch. Equipment such as 8 is installed. In addition, the main body 1 is provided with devices and circuits necessary for microwave cooking, as well as a turntable structure. This device or circuit is the fourth
In addition to what is shown in the figures, a turntable structure is shown in FIG.

Here, to explain the devices or circuits provided in the main body 1, 10 is a high voltage transformer, 11 is a plug connected to the power supply side of the high voltage transformer 10, and 12 is connected to the load side of the high voltage transformer 10. This is a high-frequency oscillation circuit composed of a magnetron 13 (which supplies microwaves into the heating chamber 2), a high-voltage rectifier 14, and a high-voltage capacitor 15.
Then, this high voltage transformer 10 and the plug 1
1, a short switch 16 (which cuts off conduction when short occurs), a timer 17 coaxially connected to the cooking time setting switch 7, an interior light 18 (which illuminates the inside of the heating chamber 2), A fan motor 19 (for cooling electrical components or ventilating the inside of the heating chamber 2) and a motor 20 (corresponding to the drive section of the present application) constituting the turntable structure are connected in parallel. Further, in series with the timer 17, a drum switch 20 is operated in conjunction with the four-sided rotating menu drum 5b, and is turned on when a high-output cooking menu is set, and turned off at other times.
In addition to the circuit 21a which is connected in parallel with the long timer switch 21 for prolonging the operation time of the timer 17, the motor 20
and the high-voltage transformer 10 is a drum switch 20b that is linked to the four-sided rotating menu drum 5b and is turned on when the low-output cooking menu is set to raw defrosting, and turned off when simmering simmered food.
A circuit 23 is installed in which a switch 22 for weak output is connected in parallel with a low output switch 22 for interrupting the power supplied to the high-voltage transformer 10, and the circuit 23 is connected in parallel with the power supply switch 22 for switching on and off the power supplied to the high-voltage transformer 10. , the output or operating time of the magnetron 13 can be controlled, and lighting, cooling, ventilation, and even the turntable structure can be driven. In addition,
In FIG. 4, 25 is a fuse, 26a and 26b are door switches that control conduction in conjunction with each other when the door 3 is closed, and 27 is an oven thermal switch that cuts off conduction when the temperature inside the heating chamber 2 becomes abnormal. However, in Figure 4, plug 1
Devices or circuits other than 1 are installed inside the main body 1.

On the other hand, the turntable structure, which is the main part of this invention, is as follows.

That is, 20 is the previously mentioned motor, 30 is
A dielectric transmission shaft made of polypropylene, glass-filled resin, etc. is rotatably provided at the center of the bottom of the heating chamber 2, 31 is a roller rotating table, and 32 is made of heat-resistant glass, plastic, etc. and has a recess 32a in the center of the back side. It is a rotating plate molded as follows. The motor 20 is located below the center of the bottom surface of the heating chamber 2, with its output shaft 20c facing upward. Note that 20d and 20e connect the motor 20 to the heating chamber 2.
The mounting plates for mounting on the lower surface of the bottom wall of the are shown respectively. Further, as shown in FIG. 2, the transmission shaft 30 has a head 33 having a non-circular cross section, for example a rectangular cross section, which protrudes above the heating chamber 2 on the upper side, and has a bottom wall of the heating chamber 2 at the lower end. In addition to having a boss portion 34 penetrating through and protruding downward, the head portion 33 has a flange portion 35a on the outer circumferential portion of the lower side of the head portion 33 in sliding contact with or close to the bottom surface of the heating chamber 2. and,
The boss portion 34 of the transmission shaft 30 and the output shaft 20c of the motor 20 form two cam locus portions 36.
The transmission shaft 3 is connected to the transmission shaft 3 by the motor 20 via a resin cam 36 having cams 36a and 36b.
0 can be indirectly driven to rotate. The cam locus portions 36a, 36b
The long timer switch 21 and the weak output switch 22 described in the above circuit are connected to the cam trajectory section 3.
The timer 21 is provided so as to be repeatedly turned on and off by the rotation of the motors 6a and 36b, and is linked to the rotation of the motor 20 to prolong the operation time of the timer 21.
Furthermore, it is possible to generate a weak output.

Further, as shown in FIG. 2, the roller rotation table 31 is formed by barring a rectangular fitting hole 45 corresponding to the cross section of the head of the transmission shaft 30 in the center of a cross-shaped table part 35, for example. In addition to being drilled by machining or the like, rollers 39 are rotatably supported on bent portions formed at each tip of the base portion 35, and each roller 39 is supported with the center of the base portion 35 as a fulcrum. It has a structure that allows it to roll along the circumferential direction. The opening size of the fitting hole 45 is set so that it can be inserted into and removed from the head 33 of the transmission shaft 30 . And the roller rotating table 31
By penetrating (inserting) the insertion hole 45 into the head 33 of the transmission shaft 30, the insertion hole 45 is inserted into the insertion hole 45 with the tip of the head 33 protruding upward from the base 35.
At the same time as the head 33 and the head 33 engage with each other, the rollers 39 are placed on the bottom surface around the transmission shaft 30, and are connected to the roller rotating table 31 by the engaging portion constituted by the head 33 and the insertion hole 45. By transmitting the rotational force, the roller rotating table 31 is rotated to the center of the transmission shaft 30, and at the same time, the rollers 39 are made to roll along the circumferential direction.
A transmission shaft head 33 that constitutes an engaging portion
An inclined part 37 is formed at the tip of the roller rotary table 31, and the inclined part 37 is inclined downwardly from the center toward the periphery as shown in FIG. As a guide when fitting into the portion 33, the roller rotating table 31 can be easily set on the head 33.

And the roller rotating table 31 arranged in this way
The recess 32a of the rotating plate 32 is rotatably engaged with the inclined part 37 at the tip of the head 33 of the transmission shaft 30 protruding from the fitting hole 45 of the rotating plate 32, guided by the inclined surface of the inclined part 37. The whole of each roller 39
...It is placed across the top.

Therefore, when performing cooking using a microwave oven configured in this way, first, as shown in FIG. Place food (item to be heated) on. From this state, rotate the four-sided rotating menu drum 5b to display the cooking menu (warm,
Defrost cooking: Cooking preparation: Raw thawing: Simmered food, stew) is positioned in the transparent window 5b, and the one suitable for cooking is selected.Then, the cooking time is set with the cooking time setting switch 7, and the cooking start switch 8 is operated. do. As a result, not only the magnetron 13 is powered on, but also devices such as the motor 20 are powered on.

From the cooking menu, select "Warm, defrost and cook"
When each cooking option of "Cooking Preparation" is selected, the drum switch 20a and the drum switch 20b are turned on, the timer 17 is set to the current operating time, and the magnetron 13 is activated with a strong output. , the drum switch 20a is turned off and the drum switch 20b is turned on, and the operation time of the timer 17 itself is extended by the intermittent operation of the timer switch 21 for a long time, and the magnetron 13 is activated with a strong output to start "simmering and simmering". When selected, the drum switch 20a and the drum switch 20b are turned off, and the timer 17 is turned off.
The operating time of the magnetron 13 is extended by turning on and off the long timer switch 21, and the magnetron 13 is automatically set to operate at a weak output by turning on and off the weak output switch 22.

Then, microwaves (high frequency waves) oscillated from the activated magnetron 13 are guided into the heating chamber 2 . On the other hand, in the turntable structure, the motor 20
The rotational force generated by The output switch 22 is turned on and off by a cam 36. Therefore, the roller 3 of the roller rotating table 31
9 rolls on the bottom surface of the heating chamber 2 along the circumferential direction, and rotates in the same direction as the roller rotating table 31 and at the rotation speed of the roller rotating table 31, using the rotating plate 32 as a fulcrum at its center engagement part. Rotate at twice the rotation speed.
Then, the microwave guided into the heating chamber 2 is irradiated onto the food rotating together with the rotating plate 32.
Food will be heated.

According to this embodiment, a dielectric transmission shaft 30 having a head 33 with a non-circular cross section is provided at the bottom of the heating chamber 2, and the rotational force of the motor 20 is transmitted to the roller rotating table 31 through this. ing.
Since the motor 20 is located below the bottom of the heating chamber 2 and its output shaft 20c does not protrude into the heating chamber 2, there is no member inside the heating chamber 2 that functions as an antenna like the conventional output shaft g. Therefore, radio waves will not leak downward from the heating chamber 2. As a result, it is possible to eliminate the conventionally required grounding plate j while preventing radio wave leakage, and thus the space around the output shaft 20c can be secured. Therefore, it is possible to provide a cam and a switch for a long timer and a weak output, as shown in FIG. 1, for example, without making it difficult to suppress radio wave leakage.

Moreover, a fitting hole 45 having an opening corresponding to the cross section of the head 11 of the transmission shaft 30 is formed in the center of the base of the roller rotation table 31, and a sloped part 37 is provided at the tip of the head 33. , roller rotating table 3
1, while keeping an eye on the head 33, which becomes the engaging part, and as long as the opening edge of the insertion hole 45 is brought into contact with the inclined part 37, it will naturally engage with the head 33 by gravity. Therefore, the roller rotating table 31 can be set easily and smoothly. Therefore, the roller rotation table 31 can be set accurately without paying special attention, and the roller rotation table 31 can be set accurately.
This makes setting work very easy. As a result, it is possible to prevent mounting errors that cause sparks and electric field concentration, as well as prevent scratches on the surface of the roller rotating table 31, rusting caused by the scratches, and deformation of the roller rotating table 31. Furthermore, damage to the transmission shaft 30 can be prevented. This also applies when removing the roller rotating table 31 from the transmission shaft 30.

Regarding the setting of the rotary plate 32, the inclined portion 3
7 is provided at the tip of the head of the transmission shaft 30, so that even when the recess 32a is slightly shifted from the head 33 of the transmission shaft 30, it can be guided by gravity using the slope of the slope 37. It naturally slides into engagement and is placed on the rollers 39 in the desired position, so that the rotating plate 32 can be easily set without paying special attention, similar to the roller rotating table 31 described above. become. Therefore, it is possible to prevent the rotary plate 32 from cracking due to forceful setting. The same applies when removing the rotary plate 32. Note that if you turn the rotating plate 32 lightly by hand, it will be easier to rotate the rotating plate 32.
can be set.

Moreover, the base portion 35 of such a roller rotating base 31
The structure in which the insertion hole 45 is provided in the transmission shaft 30
Since the head 33 of the roller simultaneously plays the role of a protrusion that was conventionally provided on the roller rotating table to support the rotary plate, the protrusion is no longer necessary, as is clear from FIG. This has the advantage that the structure of the roller rotating table 31 can be simplified and the productivity of the roller rotating table 31 can be improved. In addition, the rotating plate 32
Since the recessed portion 32a is formed in the holder, it is advantageous in terms of hygiene. That is, the transmission shaft 30 and the rotary plate 3
2, in the case where a recess is formed on the transmission shaft 30 side and a protrusion is formed on the rotary plate 32 side, there is a risk that food scraps etc. will accumulate in the recess of the transmission shaft 30. In the example, a recess 32a is formed on the back surface of the rotary plate 32, and this recess 3
2a is configured to engage with the head 33 of the transmission shaft 30, and the head 3 of the transmission shaft 30
3 has a sloped part 3 that descends from the center toward the periphery.
7, food scraps will not accumulate on the transmission shaft 30, which is advantageous in terms of hygiene.

Furthermore, if the transmission shaft 30 is separated from the motor 20, which is a drive unit that is detachably connected thereto, the bottom of the heating chamber 2 can be easily cleaned. In this case, the flange 35 is attached to the transmission shaft 30.
a, so that when the transmission shaft 30 is placed on the bottom surface of the heating chamber 2, its stability is improved.

[Effect of idea]

As explained above, according to this invention, it is possible to suppress radio wave leakage while securing space around the output shaft without requiring a grounding plate, and when installing equipment around the output shaft. Radio wave leakage can be suppressed without causing any problems. In addition, in addition to the visible engagement part, the guiding effect of the inclined part allows the roller rotary table to be easily set without paying special attention without any trouble such as damage, deformation, or incorrect installation. The rotary plate can be easily set without paying special attention without causing troubles such as twisting and cracking. Furthermore, the structure in which the insertion holes are provided in the base of the roller rotating table allows the head of the transmission shaft to simultaneously function as a protrusion that was conventionally provided on the roller rotating table to support the rotating plate. Since the convex portion is no longer necessary, the structure of the roller rotating table can be simplified, and the productivity of the roller rotating table can be improved. Furthermore, since the rotary plate has a recessed portion, it is advantageous in terms of hygiene. That is, since a recess is formed on the rotary disc side for engaging the transmission shaft and the rotary disc, and an inclined part is formed on the head of the transmission shaft so as to descend from the center toward the periphery, the transmission shaft This is advantageous in terms of hygiene, as there is no chance of food scraps accumulating in the container. Furthermore, if the transmission shaft is separated from the drive unit that is detachably connected to the transmission shaft, the bottom of the heating chamber can be easily cleaned, and when the transmission shaft is placed in the heating chamber, This has the effect of improving stability.

[Brief explanation of the drawing]

Figures 1 to 4 show an embodiment of this invention, with Figure 1 being a sectional view showing the structure of the turntable system, Figure 2 being an exploded perspective view thereof, and Figure 3 showing the external appearance of the high-frequency heating device. FIG. 4 is a circuit diagram showing its electric circuit, and FIG. 5 is a sectional view showing the structure of a turntable system of a conventional high-frequency heating device. 2... Heating chamber, 20... Motor (drive unit), 3
0...Transmission shaft, 31...Roller rotating table, 3
2... rotating plate, 32a... recess, 33... head,
35... Base portion, 37... Inclined portion, 39... Roller, 37... Inclined portion, 45... Fitting hole.

Claims (1)

[Scope of utility model registration request] a dielectric transmission shaft having a head with a non-circular cross section that is rotatably provided on the bottom of the heating chamber and has a flange at the bottom of the head; and a dielectric transmission shaft that is provided below the bottom of the heating chamber and is detachable from the transmission shaft. a drive part that is freely connected and rotates the transmission shaft; and a fitting hole that has a pedestal part in the center and corresponds to the cross section of the head part through which the head part of the transmission shaft can be freely inserted and removed. In addition, it has a plurality of rollers around the base part that can freely roll around the center of the base part, and by passing the insertion hole through the head of the transmission shaft, the insertion hole and and a roller rotating table on which the rollers are placed on the bottom surface of the heating chamber, and each roller of the roller rotating table is placed on top of the roller rotating table, and the rollers protrude from the insertion hole at the center of the back surface. A rotating plate provided with a recess that rotatably engages with the tip of the head, and a roller rotating table provided at the tip of the head of the transmission shaft, and a roller rotating plate provided at the tip of the head and a roller rotating plate provided from the center to the periphery that serves as a guide when installing the rotating plate. 1. A high-frequency heating device comprising: a sloped portion that slopes downward toward .