JPH0119358Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a high-frequency heating device equipped with a rotating plate for placing an object to be heated in an oven.

[Technical background of the invention and its problems]

In high-frequency heating devices such as microwave ovens, in order to heat the heated object efficiently and uniformly,
An oven equipped with a rotating plate is known. FIG. 12 shows a rotating plate drive mechanism of a conventional microwave oven, where 1 is an oven and 2 is a rotating plate. A motor 3 constituting a drive mechanism is provided at the bottom of the oven 1, and a transmission shaft 5 is provided on the rotating shaft 4. Further, on the bottom surface of the oven 1, there are a plurality of rollers 7 supported pivotally on a roller support plate 6.
is provided to rotatably support the rotating plate 2. This rotary plate 2 is provided with an engaging portion 8 that engages with the transmission shaft 5, so that the rotary plate 2 is rotated by the rotational force of the transmission shaft 5.

However, since the roller support plate 6 is screwed to the bottom of the oven 1 as described above, the roller support plate 6 cannot be removed. Therefore, when cleaning the inside of the oven 1, the roller support plate 6 gets in the way and it is not possible to clean every corner. Therefore, food juices and dregs tend to accumulate around the roller support plate 6, which is unhygienic.

Therefore, as shown in FIG. 13, there is also a device in which a rotating plate 9 is engaged with the rotating shaft 4, and a rotating plate 2 is placed on the upper surface of the rotating plate 9. This is because there are no protruding parts such as the roller support plate 6 on the bottom of the oven 1.
Since the rotary plate 2 is also removable, cleaning efficiency is greatly improved.

However, in the case of FIG. 13, since the weight of the object to be heated is supported only by the rotating shaft 4 of the motor 3,
The bearings 10 and 11 that pivotally support the rotating shaft 4 need to be constructed robustly, which causes an increase in costs. In addition, in order to make the rotary plate 9 detachable, the rotary shaft 4
It is necessary to provide a gap in the engaging portion 12 of the rotary plate 9 that engages with the rotary plate 9. If the object to be heated is placed at the end of the rotary plate 2, the rotary plate 2 will be tilted by the amount of the gap, and the centrifugation during rotation will occur. Combined with this force, the object to be heated may come into contact with the wall of the oven during rotation, and the bearing 10,
There is a disadvantage that uneven wear of No. 11 occurs. Also,
In the case shown in FIG. 13, since the rotary plate 2 and the rotary plate 9 rotate at the same rotation speed, the electric field within the oven 1 does not change much with respect to the food, and the absorption characteristics of radio waves to the food are not good. , heating efficiency is also poor. Another disadvantage is that the food may be heated unevenly, making it difficult to cook the food properly.

Moreover, as shown in FIGS. 14 and 15,
It is also known that a roller holder 13, in which a plurality of rollers 12 are pivotally supported, is interposed between the bottom surface of the oven 1 and the rotary plate 2. This is the rotating shaft 4 of the motor 3.
The rotation of the rotary plate 2 is transmitted via the transmission shaft 5 to the rotary plate 2 supported by the rollers 12 . Therefore, the rotary plate 2 and the roller holder 13 are removable and easy to clean, and the drive mechanism for the rotary plate 2 is structurally simple.

However, each of the rollers 12...
It simply rotates in conjunction with the rotation of the oven 1 between the bottom surfaces. For this reason, if food particles accumulate and harden on the bottom of the oven 1, or if dirt adheres to it,
Since the rotational driving force of the rollers 12 is weak, the rotation may be blocked by solid matter or dust and may come to a stop. When the roller 12 stops, the rotating plate 2
The motor rotates while slipping on the roller 12, but if this state continues, the motor 3 may become overloaded and the motor 3 may stop rotating. Therefore, it is necessary to frequently clean the bottom surface of the oven 1 to remove deposits such as solid matter and dirt. In addition, in the case of FIGS. 14 and 15, the roller holder 13 has a rotation speed of about 1/2 of the rotation speed of the rotary plate 2, but the shape is ring-shaped, and the roller holder 13 is made of dielectric material such as resin. It is made up of the body.
Therefore, there are disadvantages in that there is no radio wave diffusion or stirring effect, the heating efficiency is poor, and food may be heated unevenly.

Furthermore, when the rotating plate 2 rotates, the roller holder 13 also rotates, but the rotational deviation of the roller holder 13 is restricted by the ring-shaped protrusion 2a formed on the rotating plate 2 and the bottom of the oven 1. This is the recess 1a formed in the. in this case. When the roller holder 13 becomes misaligned in rotation, it comes into contact with the convex portion 2a and the concave portion 1a, and a force acts to return the roller holder 13 itself to the center of rotation. In other words, the rotational torque of the roller 12 is weak, and the torque of the rotary plate 2 is weakened due to contact, making it impossible to rotate normally, or if food particles or dirt adhere to the convex portions 2a and concave portions 1a, Since the torque was weak, the rotation of the roller holder 13 was hindered, and the rotary plate 2 sometimes stopped rotating. Furthermore, when food is placed on the rotary plate 2 and placed on the roller holder 13, there are two positions for positioning: the convex portion 2a and the engaging portion of the transmission shaft 5, which has the drawback of being difficult to fit.

Further, in each of the conventional rotary drive mechanisms described above, a speed reduction mechanism is provided on the rotary shaft 4 via gears 14 and 15, and a cam 16 is formed on the gear 15. In some cases, the cam 16 turns on and off the microswitch 17 to obtain a weak high-frequency output for thawing or stewing cooking. However, in general, the rotation speed of the rotary plate 2 of a microwave oven is approximately 6 to 8 rpm, which is achieved by improving heating efficiency and reducing heating unevenness.
(7.5 to 10 seconds/1 revolution) is normal. On the other hand, the weak output is approximately 50 to 40% of the normal output, and the rotation speed of gear 15 is approximately halved (approximately 3 to 4 rpm, 15 to 20%).
sec/1 revolution), the cam 16 is rotated, and the micro switch 17 is turned on and off. If the cam surface is formed so that the weak output can be taken at 50% of the normal level, the on time of the micro switch 17 will be 7.5 to 10 seconds and the off time will be 7.5 to 10 seconds, and by repeating this process, the weak output will be obtained. It's summery. In addition, if the cam surface 16 is provided directly on the rotating shaft 4, the cycle will be 7.5 to 10 seconds, and the on time of the weak output will be about 3.8 to 5 seconds, which means that the time during which high frequency waves are emitted is too short, making it difficult to use. In addition, the number of times the micro switch 17 is turned on and off is doubled, reducing its lifespan. Therefore, a speed reduction mechanism such as gears 14, 15 is required, resulting in a complicated structure and an increase in cost.

[Purpose of invention]

This idea was devised by focusing on the above-mentioned circumstances, and its purpose was to improve the cleaning efficiency inside the oven, to make it easy to attach and detach the rotary plate despite its simple structure, and to improve heating efficiency. It is an object of the present invention to provide a high-frequency heating device that can improve performance and reduce heating unevenness, reduce costs, and prevent abnormal heating near the center of rotation.

[Summary of the idea]

In order to achieve the above object, this invention includes a roller holder that is rotated by a rotation drive mechanism and is interposed between the bottom of the oven and the rotating plate, and a fitting that regulates the center of rotation of the rotating plate is attached to the roller holder. The roller holder is provided with a plurality of rollers that transmit rotational force to the rotary plate while rolling on the bottom surface of the oven, and the roller holder is provided with a plurality of rollers that roll on the bottom surface of the oven and transmit rotational force to the rotary plate. A pair of insertion holes are formed in the engagement plate attached to the engagement plate at a portion facing the lower opening of the fitting portion, a substantially linear locking portion is formed between the two insertion holes, and a substantially linear locking portion is formed between the two insertion holes. An engagement groove having a shape corresponding to the engagement portion of the engagement plate is formed on the rotating shaft of the rotation drive mechanism, and a pair of divided pieces between the engagement grooves are inserted into the engagement portion of the roller holder through the insertion hole. The rotary shaft is inserted into the space between the roller holder and the engagement plate, and the rotating shaft is engaged with the fitting portion of the roller holder.

[Example of idea]

1 to 6 show an embodiment of this invention. In FIG. 1, 21 is the main body of the high-frequency heating device, and 22 is an oven. This oven 2
An opening (insertion hole) 23 is provided at the bottom of 2,
At the bottom facing this opening 23 is a mounting plate 24.
is provided. A motor 25 constituting a rotational drive mechanism is attached to the mounting plate 24, and a rotating shaft 26 passes through the opening 23 and projects to the inner bottom of the oven 22.

On the other hand, 27 is a rotating plate on which the object to be heated is placed, and a roller holder 28 is detachably interposed between the rotating plate 27 and the bottom surface of the oven 22. As shown in FIGS. 2 and 3, this roller holder 28 has a disk shape made of metal or the like that easily reflects radio waves, and has a flange portion 29 on its outer peripheral edge. Furthermore, a fitting part 28a in the shape of a circular boss made of a convex part is provided at the center of the upper surface of the roller holder 28.
8a is adapted to fit into a recess 27a formed in the center of the lower surface of the rotary plate 27. Further, an engagement plate 30 shown in FIG. 4 is attached to the center of the lower surface of the roller holder 28 so as to cover the lower opening of the fitting portion 28a. This engagement plate 30 has a fitting portion 2.
A pair of insertion holes 31, 31 are formed in a portion facing the lower opening of 8a, and a substantially linear locking portion 32 is formed between these insertion holes 31, 31. Furthermore, the rotation shaft 2 of the motor 25
An engagement groove 33 having a shape corresponding to the engagement portion 32 of the engagement plate 30 is formed at the upper end of the engagement plate 6 . and,
A pair of divided pieces 34, 34 on both sides of this engagement groove 33
is inserted into the space 35 between the fitting part 28a of the roller holder 28 and the engaging plate 30 through the insertion holes 31, 31 of the engaging plate 30, and the rotating shaft 26 and the fitting part 28a of the roller holder 28. and are engaged with each other. Furthermore, four roller shafts 36 are protruded from the flange portion 29 of the roller holder 28 at equal intervals, and rollers 37 are rotatably supported on these roller shafts 36. Therefore, the roller 3 supported by this roller holder 28
7... is a roller holder 28 that is interposed between the bottom surface of the oven 22 and the bottom surface of the rotary plate 27 and rotates.
As the rollers 37 rotate, the rollers 37 roll on the bottom surface of the oven 22, and the rotation is transmitted to the rotating plate 27. Further, the roller contact surfaces 38 and 39 on the bottom surface of the oven 22 and the bottom surface of the rotary plate 27 that contact the roller 37 are provided with ring protrusions 40 and 4.
1. Further, as shown in FIG. 5, a cam 42 is fitted onto the rotating shaft 26 of the motor 25, and a micro switch 43 is mounted on the cam surface.
has been contacted. In addition, 44 is a magnetron,
45 is a waveguide.

Next, the operation of the above embodiment will be explained. first,
When the motor 25 is energized, the rotating shaft 26 rotates at a required rotation speed (for example, 3 rpm), and this rotation is transmitted to the roller holder 28 via the engagement plate 30. When the roller holder 28 rotates, the rollers 37 roll on the bottom surface of the oven 22 due to this rotational force. When the roller 37... rolls, this roller 37...
The rotational force is transmitted to the rotating plate 27 that is in contact with the
In the same direction as the roller holder 28, the roller holder 28
It rotates at twice the rotation speed (6 rpm). That is,
As shown in FIG. 6, when the roller 37, which was initially at position A, rotates half a turn and advances a distance a to position B, as the roller 37 rotates, the rotating plate 27 moves to
It is moved from the position to the W position and comes to the Y position. Therefore, when the roller 37 makes a half rotation, the roller holder 28 advances by a distance a, and the rotary plate 27 moves 2×a from the W position to the Y position. After one rotation, the roller 37 advances by a distance b from A to C, and the rotary plate 27 moves to positions V to Z, and rotates in the same direction as the roller holder 28 at twice the number of rotations. At this time, the cam 42 fitted on the rotating shaft 26
The micro switch 43 is turned on and off by the cam surface. In addition, when the weak output is set to 50% of the normal output, the on time is 10 seconds,
The off time is also 10 seconds (cycle 20 seconds). At this time,
The rotation of the rotary plate 27 is given a rotational driving force by the rollers 37, but the center of rotation is the fitting part 2.
8a and the recess 27a, the torque is strong and normal rotation is possible, and since the fitting part 28a and the recess 27a are located on the underside of the rotating plate 27, food particles and dirt do not adhere to the rotating plate 27. Allows for smooth rotation.

Therefore, in the case of the above structure, the number of rotations of the roller holder 28 made of a metal material that reflects radio waves, and the rotation plate 27 made of a material such as glass or plastic that transmits radio waves. Since the rotation speeds of the rotating plate 27 and
The entire food placed on top can be uniformly irradiated. Furthermore, since the roller contact surfaces 38 and 39 on the bottom surface of the oven 22 and the bottom surface of the rotary plate 27 that come into contact with the roller 37 are formed into ring convex strips 40 and 41, even if food particles accumulate, they can be easily wiped off, making cleaning easier. In addition, the weight of the food is easily distributed over the entire bottom surface of the oven 22, making it difficult to deform. Therefore, cooking can be done in a stable electric field. Moreover, roller 3
7 has an arcuate outer circumferential surface, so it almost makes point contact with the roller contact surfaces 38 and 39, reducing the probability of contact with food particles and garbage, and preventing vibrations and abnormal noises of the rotary plate 27. can. Further, an engagement plate 30 is provided on the lower surface of the roller holder 28 so as to cover the lower surface opening of the fitting portion 28a, and the engagement plate 30 is provided with insertion holes 31, 31 and a locking portion 32, and the rotation of the motor 25 is also provided. An engagement groove 33 having a shape corresponding to the locking portion 32 of the engagement plate 30 is provided on the shaft 26, and the divided pieces 34, 34 on both sides of this engagement groove 33 are inserted into the insertion holes 31, 31 of the engagement plate 30. By this, the fitting portion 28a of the rotating shaft 26 and the roller holder 28
The engagement portion with the rotation shaft 26 on the roller holder 28 side can be integrally molded with a flat engagement plate 30.
It is possible to reduce production costs. Furthermore, the fitting portion 28a of the roller holder 28 and the engagement plate 3
A space 35 is formed between the rotating shaft 26 and the engagement plate 30 of the roller holder 28, and this space 35 forms a check chamber that attenuates radio waves. can be prevented.

Note that this invention is not limited to the above embodiments. For example, as shown in FIGS. 7 to 9, a ring-shaped guide member 51 may be provided on the lower surface of the engagement plate 30 through which the rotating shaft 26 of the motor 25 is inserted. In this case, the rotating shaft 26 and the roller holder 2
When engaged with 8, it is possible to prevent rattling between the two. Therefore, it is possible to maintain the rotating shaft 26 and the roller holder 28 in close contact with each other and to maintain them at substantially the same potential, thereby making it possible to more reliably prevent sparks and abnormal heating. Furthermore, since the roller holder 28 can be guided by the guide member 51 when it is inserted into the rotating shaft 26, the work of inserting the roller holder 28 can be easily performed.

Further, as shown in FIG. 10, the roller holder 28 has a substantially fan-shaped opening 52 centered around the engaging portion 28a.
A plurality of arms 61 may be formed between each of these openings 52, 52, and arm-shaped radio wave stirring parts 53 may be formed between the openings 52, 52, and as shown in FIG. 11, four arms 61 may be formed around the engaging part 28a. may be arranged in a cross shape, and the rollers 37 may be pivotally supported at the tips of the arms 61. Furthermore, it goes without saying that various other modifications can be made without departing from the gist of the invention.

[Effect of idea]

As explained above, according to this invention, the driving force of the rotational drive mechanism is transmitted to the roller holder, and this rotational force causes the roller to roll on the oven bottom and rotate the rotating plate. Even if there is food particles or dirt on the surface, the rollers can roll over them and rotate smoothly. Therefore, there is no need to frequently clean the bottom surface of the oven, and the cleaning performance is greatly improved. Furthermore, since the roller holder is provided with a fitting portion that regulates the center of rotation of the rotary plate, it is possible to prevent rotational wobbling of the rotary plate and to facilitate positioning. Moreover, since the rotating plate is supported by multiple rollers of the roller holder,
This also has the effect of preventing the rotating plate from tilting and improving durability. Furthermore, a pair of insertion holes are formed in the engagement plate attached to the lower surface of the roller holder so as to cover the lower surface of the fitting portion at a portion facing the opening on the lower surface of the fitting portion, and these holes are inserted through both of the holes. A substantially linear locking portion is formed between the holes, and an engagement groove having a shape corresponding to the locking portion of the engagement plate is formed on the rotating shaft of the rotary drive mechanism, and a pair of locking portions between the engagement grooves are formed. Since the rotating shaft is engaged with the fitting part of the roller holder while the divided piece is inserted into the space between the fitting part of the roller holder and the engagement plate through the insertion hole, the manufacturing process is easy. In addition to being able to reduce costs,
Abnormal heating near the center of rotation can be prevented.

[Brief explanation of drawings]

Figures 1 to 6 show an embodiment of this invention, in which Figure 1 is a vertical sectional view of the entire microwave oven, Figure 2 is a vertical sectional view showing the rotational drive mechanism, and Figure 3 is a roller holder. , FIG. 4 is a perspective view showing the engagement plate and the rotating shaft, FIG. 5 is a plan view of the cam, FIG. 6 is a schematic configuration diagram for explaining the operation, and FIGS. 7 to 9 are separate. Fig. 7 is a longitudinal sectional view showing the rotational drive mechanism, Fig. 8 is a perspective view showing the mounting state of the guide member, and Fig. 9 shows the engagement plate with the guide member and the rotating shaft. FIGS. 10 and 11 are perspective views showing further different embodiments, and FIGS. 12 to 14 are longitudinal sectional views showing different conventional rotary plate drive mechanisms.
FIG. 15 is a perspective view of the roller holder of FIG. 14. 22...Oven, 25...Motor (rotation drive mechanism), 27...Rotating plate, 28...Roller holder, 28
a... Fitting portion, 30... Engagement plate, 31... Insertion hole, 32
...Locking portion, 33...Engagement groove, 34...Divided piece, 35...
Space, 37... Laura.

Claims (1)

[Claims for Utility Model Registration] (1) An oven, a rotating plate provided in the oven on which a heated object is placed, and an oven removably interposed between the bottom of the oven and the rotating plate. a roller holder, a boss-shaped fitting part provided at the center of the roller holder and protruding toward the rotating plate to regulate the center of rotation of the rotating plate; an engagement plate that is attached to the lower surface of the roller holder and has a substantially linear locking portion formed between a pair of insertion holes formed in a portion facing the lower surface opening of the fitting portion; and a bottom portion of the oven. An engagement groove having a shape corresponding to the locking part of the engagement plate is formed in the insertion part provided in the insertion part and inserted into the fitting part of the roller holder, and a pair of divided pieces on both sides of this engagement groove are inserted into the insertion part. a rotational drive that engages with the fitting portion of the roller holder and applies rotational force to the roller holder when inserted into a space between the fitting portion of the roller holder and the engagement plate through a hole; A high-frequency heating device comprising: a mechanism; and a plurality of rollers that are rotatably supported by the roller holder and transmit rotational force to the rotary plate while rolling on the bottom surface of the oven. (2) The high-frequency heating device according to claim 1, wherein the engagement plate has a ring-shaped guide member attached to the lower surface thereof through which the rotation shaft of the rotation drive mechanism is inserted.