JPS5940434B2 - High frequency thawing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a high frequency thawing device for frozen products, etc., and is aimed at improving insulation properties.

In conventional defrosting using dielectric heating, the defrosting operation is generally performed using a high frequency of several MH2 or higher. FIG. 1 shows a thawing device that performs dielectric heating and thawing at a relatively low frequency such as 13MH27), which has two electrodes, upper and lower, sandwiching the thawed object. In the figure, reference numeral 1 denotes a thawing chamber, the bottom surface of which is a mounting plate 2 made of an insulator, and the side, rear, and top surfaces of the thawing chamber wall 3 made of a highly conductive material such as aluminum. Reference numeral 4 denotes an object to be thawed, and an upper electrode 5 connected to the ground side is movably attached to the upper part by an electrode lifting device 6.

T is an electrode box provided below and above the mounting plate 2 of the thawing chamber 1, and the electrode box T and the wall surface 3 of the thawing chamber are electrically connected. A lower electrode 8 is provided inside the electrode box T with a predetermined gap between the mounting plate 2 and the electrode box T, and is connected to the high voltage side.

A high frequency oscillator section 9 supplies high frequency energy to the object 4 to be thawed, and is shielded to prevent noise from leaking to the outside.

Reference numerals 10 and 11 are power supply lines that feed power to the lower electrode 8 and the upper electrode 5, respectively.

In terms of the circuit, the thawing chamber wall 3, the electrode box T, and the chassis of the high frequency oscillator section 9 are grounded together with the upper electrode 5. The problem with this configuration is that during thawing, trip (gravy) flows out from the thawed object 4, flows on the mounting plate 2, and comes into contact with the thawing chamber wall surface 3 (see arrow A in Fig. 1). That's true.

Tripp, which is water, has a very large dielectric constant, so
High frequency electric field is concentrated. Therefore, a high-frequency current trips between the lower electrode 8 on the high voltage side and the wall surface 3 of the defrosting chamber (see arrow A).
This is extremely dangerous as it causes the mounting plate 2 to track, causing charcoal on the mounting plate 2 to emit smoke, ignite, and cause equipment to catch fire. As described above, conventional defrosting devices have poor insulation properties.

The present invention provides a high-frequency decompressing device that eliminates the drawbacks of the conventional technology.
This will be explained using figures.

In the figure, 1 is a thawing chamber, which is composed of a mounting plate 2, a thawing chamber wall 3 made of a grounded and conductive material, and an object 4 to be thawed is stored in the thawing chamber 1. . 5 is an upper electrode connected to the ground side, which is provided on the upper part of the object to be thawed 4;
The object 4 to be thawed is covered with a cover 5' made of an insulator so that it does not come into direct contact with the upper electrode 5.

The upper electrode 5 is fixed to an electrode lifting device 6 so that its height can be adjusted according to the thickness of the object 4 to be thawed. Reference numeral 7 designates an electrode box, which is electrically connected to the wall surface 3 of the thawing chamber over the entire circumferential wall. It has a lower electrode 8 provided with a gap.

This lower electrode 8 is connected to the high voltage side. 9 is a high frequency oscillator that supplies high frequency energy; 12 is a power supply section;
0, 11.13 are power supply lines that respectively supply power to the lower electrode 8, the upper electrode 5, and the high frequency oscillator section.

Reference numeral 14 denotes an L-shaped plate-like insulator, one side of which is formed by the bottom surface of the thawing chamber wall 3 and the top surface of the electrode box 7.
It is also fixed in the shape of a sasso german tree.

Further, a sealant 16 such as silicone is interposed between the mounting plate 2 and the insulator 14. The other side is the wall surface of the thawing chamber 3VC
It is standing upwards. The height thereof is a predetermined height that determines the insulation distance from the upper surface of the mounting plate 2 to the wall surface 3 of the defrosting chamber, for example, a height of about 30 cm. In order to maintain the thawing chamber 1 in a cool atmosphere, it is equipped with a cooling coil 16, a cooling fan 17, a condensing coil 18, a compressor 19, etc., and communicates with the thawing chamber 1 through an intake port 20 and an exhaust port 21. There is.

22 is the main body of the decompressing device divided by the main body of the decompressing device.

FIG. 4 is a schematic circuit diagram of the main part of the present invention. As shown in the figure, the thawing chamber wall surface 3, the upper electrode 5, and the high frequency oscillator section 9
chassis is grounded. The decompression operation of the present invention will be explained next. When the object 4 to be thawed is stored in the thawing chamber 1, the upper electrode 5 is grounded to the object 4 to be thawed, or adjusted to provide an appropriate gap, and the power supply section 12 and the high frequency oscillator section 9 are operated, the object to be thawed is It is heated due to the dielectric loss of 4 and begins to thaw. At this time, since cold air is blown into the thawing chamber 1 and the object 4 to be thawed is thawed while being cooled, uniform thawing is achieved. However, as the thawing progresses, the trip flows out from the thawing object 4, or in the case of an ice-packed thawing object, such as an shrimp block, the ice melts and becomes water, which locally thaws on the mounting plate 2. Although it flows in the direction of the chamber wall surface 3, the insulator 14 prevents it from coming into contact with the thawing chamber wall surface 3. Further, since the insulator 14 stands up on the upper blade at a predetermined height, there is a sufficient insulation distance.

That is, there is no short circuit between the lower electrode 8, which is the high voltage side, and the ground side, and no tracking occurs. In addition, since the sealant 15 is interposed between the insulator 14 and the mounting plate 15, moisture and trips do not pass through the gap and accumulate in the section B shown in FIG. , there is no contact with the ground side of the electrode box, etc., and no tracking occurs.

As described above, the present invention has extremely high insulation properties and can provide a safe thawing device that does not generate charcoal, smoke, fire, etc. Also, its reliability is extremely high.

[Brief explanation of drawings]

Figure 1 is a schematic cross-sectional view of the main parts of a conventional high-frequency thawing device;
The figure is a sectional view of a high frequency defrosting device according to an embodiment of the present invention, FIG. 3 is an enlarged sectional view of the main part of the same device, and FIG. 4 is a schematic circuit diagram of the main part of the same device. 1... Thawing chamber, 2... Placement plate, 3...
... Defrosting chamber wall, 4... Items to be thawed, 5...
...Top electrode, 8...Bottom electrode, 14...
····Insulator.

Claims (1)

[Scope of Claims] 1 A defrosting chamber, a high-frequency oscillator, and a pair of electrodes are provided, the lower electrode provided at the bottom of the defrosting chamber is connected to the high voltage side, and the upper electrode provided inside the defrosting chamber is connected to the ground side, A high-frequency thawing device characterized in that an insulator is interposed between a mounting plate constituting the bottom of the thawing chamber and the bottom of a wall of the thawing chamber connected to the ground side. 2. The high-frequency thawing device according to claim 1, wherein the insulator has an L-shape, and one side of the insulator stands up a predetermined length from the wall of the thawing chamber. 3. The high frequency thawing device according to claim 1 or 2, wherein a sealant is interposed between the insulator and the mounting plate.