JPH0228769B2 - KOSHUHAKANETSUSOCHI - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to high frequency heating devices such as microwave ovens.

Conventional Structure and Its Problems FIG. 1 is a sectional view showing the structure of a conventional high-frequency heating device. In FIG. 1, a door 2 is provided at the front of a heating chamber 1 so as to be openable and closable. A waveguide 3 is connected to the heating chamber 1, and a magnetron 4 is provided thereto. The radio waves oscillated from the magnetron 4 are irradiated into the heating chamber 1 through the waveguide 3. The object to be heated 5 is placed on a rotating plate 6, and is rotated by a motor 7 during heating to uniformly heat the object. . In this way, the object to be heated 5 is heated by radio waves, but according to such a conventional high-frequency heating device, the user can set the heating time according to the amount and weight of the object to be heated 5 using a time switch or the like. It was a pain to have to set it up each time.

OBJECTS OF THE INVENTION The present invention solves the above-mentioned conventional drawbacks, and aims to measure the weight of an object to be heated and to automatically heat the object without setting a heating time.

Structure of the Invention In order to achieve the above object, the high-frequency heating device of the present invention supports a rotating mounting table with an elastic body, and uses a detector to detect the frequency of vertical vibration of the rotating mounting table when an object to be heated is placed on the rotating mounting table. By doing this, the weight of the object to be heated is measured and the heating time is automatically determined without having to set the heating time each time.

Then, a pressing mechanism is provided that is linked to the opening and closing of the door, and when the door is open, the rotating mounting table is pushed down or pushed up, and when the door is closed, it is quickly returned to its original position. This is a configuration that activates vibrations. Furthermore, the pressing force of the pressing mechanism is generated through an elastic body. This configuration has the effect of generating stable and reliable vibrations, increasing measurement accuracy by measuring this stable and reliable frequency, and enabling stable heating with a more stable heating time. .

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below based on the drawings.

FIG. 2 is a partial sectional view of the high frequency heating device according to the present invention. In FIG. 2, a door 12 is provided at the front of the heating chamber 11 so as to be openable and closable. Heating chamber 1
1 is irradiated with radio waves oscillated from a magnetron (not shown) to heat the object 13 at high frequency. The object to be heated 13 is placed on the rotating plate 14.
is placed on the rotary mounting table 15. Rotating mounting table 1
5 is fitted onto a shaft 17 of a motor 16, and is driven to rotate by the motor 16. Motor 1
6 is fixed to block A18, which is connected to block B20 by a plurality of leaf springs 19, and block B20 is fixed to the bottom 21 of the main body. Block A18, block B20, leaf spring 1
9 constitutes a roberval mechanism, so that the motor 16 fixed to the block A18 moves elastically vertically up and down. A magnet 22 is provided in the block A18, and a detection coil 23 is provided opposite to the magnet 22. The motor 16 moves downward according to the weight of the object 13 to be heated. In addition, the motor 16 is connected to the heated object 1.
3 and the elasticity of the leaf spring 19. The detection coil 23 extracts the amount of displacement or vibration frequency of the magnet 22 as an electrical signal.

Further, a lever 24 is provided to push down the tip of the block A18, and the lever 24 is provided with a contact portion 24a, and a cam 25 is provided at a position opposite to the contact portion 24a.
The lever 24 is rotationally displaced around the shaft support 24b. The shaft support 24b is slidable in the vertical direction and is pushed upward by a compression spring 24c. The cam 25 is connected by a groove 28 to a pin 27 which is rotatably driven by an arm lever 26, and the groove 28 is made slightly wider than the pin 27 to provide a gap, so-called play. The upper end of the arm lever 26 is rotatably connected to a door arm 29 provided on the door 12. The door arm 29 slides on rollers 30 provided within the main body to smoothly open and close the door 12.

The door arm 29 is biased in the pulling direction by the door spring 31. The operation of the above configuration will be explained below. When the door 12 is open, the arm lever 26 moves to the position shown by the two-dot chain line, the pin 27 rotates, the cam 25 rotates, and the abutment part 24a of the lever 24 is pushed down, so the lever 24 is moved to the position shown by the two-dot chain line. Along with this, block A18 moves to the position shown by the two-dot chain line. When the door 12 is closed, the rotating mounting table 15
Although there is a step h with respect to the bottom surface of the heating chamber, the rotary mounting table 15 approaches the bottom surface of the heating chamber due to the movement of the block A18. On the other hand, when closing the door 12, the arm lever 26 is moved by the door arm 29, the cam 25 is rotated, and the lever 24 is returned to its original position.

At this time, since there is some play between the pin 27 and the groove 28, when the concave part of the cam 25 touches the contact part 24a, the cam 25 slides down along the slope. Because it rotates,
The contact portion 24a slides down the cam 25 at once. In this way, when the abutting portion 24a returns, it returns quickly. As a result, the block A18, the rotary mounting table 15, the object to be heated 13
suddenly returns upwards when the door 12 is closed, and at this time vertical vibrations occur. The vibration frequency generated at this time is detected by the detection coil 23 as the movement of the magnet 22, and the overall weight is measured from the output.

Here, the shaft support 24b of the lever 24 is slidable in the vertical direction, and is pushed upward by a compression spring 24c. For this reason, cam 2
5 pushes down the contact part 24b, the lever 24
The greater the force with which the block A18 is pushed upward by the leaf spring 19, the lower the shaft support 24b becomes, and the less the lever 24 pushes down the block A18. In other words, if the weight of the object to be heated 13, etc. placed on the rotating mounting table 15 is small, the block A18 will tend to rise upwards, causing the shaft support 24b to fall; on the other hand, if the weight is large, the block A18 will tend to fall downwards. Therefore, the shaft support 24b rises. For this reason, the amount by which the lever 24 pushes down the block A18 does not change much depending on the weight of the object placed on the rotary mounting table 15, and therefore the block A18, the rotary mounting table 15, and the object to be heated 13 are kept constant and stable. Stable and reliable weight measurement is possible because it performs vertical vibration with stable amplitude.

FIG. 3 shows another embodiment of the high-frequency heating device according to the present invention, and is an exploded perspective view showing the main components. In FIG. 3, parts that are the same as those in FIG. 2 are indicated by the same numbers with dashes attached.

In FIG. 3, a door 12' is provided to be able to open and close with respect to the heating chamber, and a door arm 29' slides on rollers 30 provided on the main body to facilitate opening and closing.

The motor 16' is fixed to the block A18', and is connected to the block B2 by a plurality of leaf springs 19'.
0', and the block B20' is fixed to the bottom part 21' of the main body. An arm lever 26' is rotatably connected to the door arm 29', a cam 41 is integrally provided with the arm lever 26', and the arm lever 26' is rotationally driven by the lever 26'. A lever B42 is brought into contact with the cam 41, and the lever B42 is rotatably supported by a pin 44 fixed to a shaft 43. Lever B spring 45 is lever B
42 is a coil spring that pulls the cam 41 in the thrust direction. A lever C46 made of a spring material is fixedly provided at the other end of the shaft 43, and its tip is opposed to the abutment part 18'a integrally formed with the block A18'.
It is biased in the direction away from 8'a.

FIG. 4 is a perspective view showing a part of the cam and lever of the high-frequency heating device according to the present invention.

In FIG. 4, the cam 41 is provided with a small diameter part 51 and a large diameter part 52, and the side surface 48 of the lever B42 is brought into contact with the cam 41, and the rotation of the cam 41 moves the lever B42 to the cam 4.
1 in the radial direction. The narrow diameter portion 51 is configured with a thrust surface A53, and the large diameter portion 52 is configured with a thrust surface B54 provided with a step.
A perspective surface 55 connecting the thrust surface B54 and the thrust surface B54 is provided. This thrust surface A53, thrust surface B54,
The inner surface 49 of the lever B42 comes into contact with the inclined surface 55, and the lever B42 moves in the thrust direction.

FIG. 5 is a side view showing a portion of the lever C46 and the abutting portion 18'a of the block A18' of the high-frequency heating device according to the present invention.

In FIG. 5, a indicates the operating state of the contact portion 18'a and the lever C46 when the object to be heated (not shown) is light, and the solid line indicates the state before being pushed down by the lever C46, and the state in which it is pushed down is shown by a two-dot chain line. b similarly shows the case where the object to be heated is heavy, and the abutment part 18' by the lever C46 is shown.
The amount of depression of a is indicated by X ₁ and X ₂ , respectively.

The operation of the embodiment shown in FIGS. 3, 4, and 5 will be explained below.

The sliding path of the lever B42 on the cam 41 is shown by a dashed arrow. FIG. 3 shows a state in which the door 12' is closed, and the side surface 48 of the lever B42 is
The lever C is brought into contact with the narrow diameter portion 51 by the biasing force of the spring 47. The path on the cam 41 is point A. In this state, the lever C46 is
It is far from a.

Next, when the door 12' is opened to the half-open position,
The large diameter portion 52 of the cam 41 pushes the lever B42 outward in the radial direction. The path on the cam 41 is point B. As a result, the lever B42 rotates to the left, and this rotational force is transmitted through the shaft 43, rotating the lever C46, whose tip presses down the abutting portion 18'a. This allows the rotating mounting table (not shown)
is pushed down to near the bottom of the heating chamber. At point B, the lever B42 has an inner surface 49 that is thrust at the thrust surface A due to the force of the lever B spring 45.
53 to the thrust surface B54.

When the door 12' is fully opened, the cam 41 rotates further and the path on the cam 41 reaches point C. When the door 12' begins to close, the path makes a U turn, but since the side surface 48 of the lever B42 slides only on the large diameter part 52, the lever B42 does not move, and the abutting part 18'a remains pressed down. be.

Then, when the door 12' is closed just before closing, the path reaches point D. Then, the inner surface 4 of lever B42
9 slides on the inclined surface 55, and the inner surface 49 overcomes the tensile force of the lever spring 45 and moves from the thrust surface B54 to the thrust surface A53. At the same time, the side surface 48 of the lever B42 comes off from the large diameter portion 52, and the lever C spring It moves to point A of the narrow diameter portion 51 by a force of 47. At this time, the lever B42 moves quickly and quickly, and accordingly, the lever C46 also moves quickly to release the pressing part 18'a. By the way, if the object to be heated is light, the contact part 18'a is at a high position, so the lever C
46, the lever C46 is largely deflected by the reaction force of the plate spring 19, and when the object to be heated is heavy, the lever C46 deflects little.
The amounts of depression X ₁ and X ₂ due to this are similar values.

In this way, according to this embodiment, the pressing is quickly released by closing the door, so at this time, the rotary mounting table has a unique function according to the weight of the object to be heated and the elasticity of the leaf spring. It can generate vertical vibration. In this case, a constant amount of pressure can be obtained that is not greatly affected by the weight of the heated object, so
Since the amplitude of the vertical vibration can be made stable and reliable, by detecting this frequency with a detector, the weight of the object to be heated can be measured stably and reliably, and there is no need to set the heating time each time. This also has the effect of automatically setting the heating time.

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

(1) When placing a rotating plate or an object to be heated on the rotating mounting table, the rotating mounting table does not vibrate up and down, so it is stable, and there is no need to worry about spilling or unstable heating objects such as liquids. Since it can be used without feeling, the operation feeling is better and it is easier to use. It is also easy to clean the inside of the heating chamber.

(2) Due to the function of the pressing mechanism that allows the rotating mounting table to quickly return to its original position when the door is closed,
A certain vibration is generated upon return, and a large signal can be obtained as a detector signal. Therefore, external vibrations that may be applied depending on the installation location of the main body, so-called noise vibrations, can be clearly distinguished (the S/N ratio becomes large), allowing highly accurate detection. Furthermore, since constant pressing is obtained that is not affected by the weight of the object to be heated, vibrations with a constant amplitude can be obtained, allowing for more accurate and reliable detection.

(3) If the amplitude of the vibration of the rotary mounting table and the heated object changes depending on the weight of the heated object, the vibration will be large in some cases and small in other cases, making it difficult for the user to However, according to the present invention, a constant amplitude can be obtained and the commercial value is high.

(4) In addition, if the minimum detectable amplitude is regulated, and the amplitude changes depending on the weight of the heated object, the amplitude will inevitably become larger when the weight is light.
There has been a risk that the object to be heated may move due to vibration or spill if it is a liquid, but according to the present invention, these can be prevented.

(5) By configuring the part of the pressing mechanism that acts on the rotary mounting table with a leaf spring, a constant amplitude that is not affected by the weight of the heated object can be obtained by the vibration of the rotating mounting table and the heated object with a simpler structure. .

(6) In this case, since the structure is simple, it is advantageous in terms of life and reliability, and the cost can be reduced.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing the structure of a conventional high-frequency heating device, Fig. 2 is a partial sectional view showing one embodiment of the high-frequency heating device of the present invention, and Fig. 3 is the main structure of another embodiment of the same device. FIG. 4 is a perspective view showing a portion of the cam and arm lever of the device, and FIG. 5 is a side view showing a portion of the abutting portion and lever C of the device. 12... Door, 13... Heated object, 15...
Rotating mounting table, 16...Motor, 18...Block A, 19...Plate spring, 20...Block B, 24
...Lever, 24c...Compression spring, 25...Cam, 26...Arm lever, 29...Door arm, 41...Cam, 42...Lever B, 43...
Shaft, 46...Lever C.

Claims (1)

[Scope of Claims] 1. A heating chamber, an oscillator that supplies radio waves to the heating chamber, a door that opens and closes the heating chamber, a rotary mounting table on which an object to be heated is placed in the heating chamber, and a rotating mounting table for placing an object to be heated in the heating chamber. an elastic body that supports a mounting table, and a detector that detects the movement of the rotating mounting table or the elastic body as a vibration frequency and measures the weight of the heated object in order to automatically determine the heating time of the heated object; A pressing mechanism that is interlocked with the door and has a quick-acting mechanism that maintains the rotary mounting base in a depressed or pushed-up state when the door is opened, and immediately releases the pushed-down or pushed-up state when the door is closed. and a high-frequency heating device configured to apply the pushing down or pushing up force of the pushing mechanism to the rotating mounting table via an elastic body. 2. The high-frequency heating device according to claim 1, wherein the portion of the pressing mechanism that acts on the rotary mounting table is formed of a plate spring.