JPH0218478Y2 - - Google Patents

Description

[Detailed explanation of the invention] [Industrial application field] For example, as a method for dyeing thread, there is a method (cheese dyeing) in which the thread is wrapped around a core of a synthetic resin pipe or woodwind and is dyed in a state called cheese. Since cheese dyed using this dyeing method takes a long time to dry, an attempt has been made to solve this problem by forcibly drying it using high-frequency dielectric heating in a depressurized airtight container (tank) after dehydration. .

The present invention relates to a high-frequency vacuum dryer for heating and drying materials containing a large amount of moisture, such as dried dyed cheese, and more specifically relates to a structure that prevents sparks (high-frequency discharge).

[Conventional technology]

For example, the high frequency vacuum dryer is
Like the wood drying device disclosed in No. 76201,
The idea is to sandwich the wood to be dried between two electrodes under constant pressure and dry it using high-frequency heating.
As disclosed in Japanese Patent Application Laid-Open No. 59-60170, a large number of plywoods or veneers are fed and stacked between electrodes arranged at an angle at regular intervals, and the ones fed first are sequentially taken out. The concept behind the ceremony is well known.

In addition, in a high-frequency vacuum dryer that attempted to heat and dry a large number of single items such as dyed cheese on a lower electrode at once, the upper and lower electrodes were both arranged horizontally. .

[Problem that the invention attempts to solve]

In the case where the material to be dried is sandwiched between two electrodes and heated, the problem of moisture evaporating from the sides and condensation on the opposing surfaces of the electrodes does not occur. However, in the case where the upper and lower electrodes are arranged horizontally and a material to be dried with a high moisture content is placed on the lower electrode with a gap between them and the upper electrode, some of the water vapor generated from the material to be dried is When it comes into contact with the lower surface of the upper electrode, condensation occurs there, which becomes water droplets and falls onto the object to be dried, causing stains, and there is a possibility that sparks may be generated between the upper electrode and the object to be dried through the water droplets. It was hot. When a spark occurs, the material to be dried is scorched and an overcurrent flows, which activates a safety device and stops the operation. Therefore, the generation of sparks results in defective products and reduces work efficiency.

In view of the above drawbacks, the present invention aims to provide a high-frequency vacuum dryer in which the object to be heated is placed on the lower electrode of upper and lower electrodes arranged in parallel, with a structure that prevents the generation of sparks. do.

[Means for solving problems]

The vacuum dryer according to the present invention consists of a closed container 1 that can suck the air inside and reduce the pressure using a vacuum generator.
, an upper electrode 2 fixed within the closed container 1, and a lower electrode 3 which is movable in and out of the closed container 1 and directly faces the upper electrode 2 within the closed container.

First, the upper electrode 2 and the lower electrode 3
The lower electrode is tilted horizontally with respect to the moving direction of the lower electrode at a slight angle that allows the object to be dried to be stably placed on the lower electrode. Second, the lower surface of the upper electrode 2 has a rough finish called a satin finish. The lower side end 2a of the third inclined upper electrode 2 is made to extend further outward than the lower side end 3a of the lower electrode 3 that directly opposes it.

[Effect]

As shown in FIG. 3, the dyed material A to be dried, such as cheese, is placed on the lower electrode 3 pulled out from the closed container 1, and after entering the closed container and sealing it, the vacuum generator 4 The air inside the sealed container is sucked out to reduce the pressure. Thereafter, when a high frequency current is applied between the upper and lower electrodes, the material to be dried A on the lower electrode generates heat (high frequency heating), and the moisture in the material to be dried becomes water vapor and evaporates. Most of the water vapor generated from the material to be dried is sucked and exhausted by the vacuum generator 4, but some of the water vapor condenses on the lower surface of the upper electrode 2.

The fine water droplets that have condensed on the lower surface of the upper electrode 2 try to grow into larger droplets, but in this invention, since the lower surface of the upper electrode is rough, the water droplets that have formed on the surface are At this stage, adjacent water droplets combine to form a thin film of water over the entire surface without growing into large droplets. Since the upper electrode is tilted at a slight angle in the left-right direction, the condensed water does not grow into large water droplets and falls as drops from the lower side end 2a of the upper electrode 2. At this time, since the lower side end 2a of the upper electrode extends further outward than the lower side end of the lower electrode, drops falling from the lower side end 2a of the upper electrode do not fall on the object to be heated. There is no risk of sparks occurring between the water droplets that are about to fall and the object to be heated.

〔Example〕

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In the embodiment shown in FIGS. 3 and 4, the closed container 1 is a cylindrical tank, and an upper electrode 2 and a lower electrode 3 are arranged inside the tank. The upper electrode 2 is suspended and fixed in the closed container 1, while the lower electrode 3 is fixed on a support 5, and one end of the support 5 is fixed to one end plate 6 which can be opened and closed. Further, the mirror plate 6 is mounted on a trolley 7, which is movable along the rails 8. Wheels 9 are attached to the tip of the support base 5, and the support base 5 moves along a guide rail 10 laid inside the closed container 1. By pulling out the cart 7, the lower electrode 3 is pulled out from the closed container 1, and operations such as replacing the dried material placed on the lower electrode can be performed outside the container.

Electrode manholes 12, 12 are connected to the upper electrode 2 and lower electrode 3 from the high frequency regulator 11a, respectively.
It is wired through. Further, another manhole 13 is provided at the top of the closed container 1, and this is connected to the vacuum generator 4 through piping, so that the air inside the closed container 1 is sucked. Further, a drain port 14 is provided at the lower end of the closed container 1 to drain water accumulated in the closed container.

If the upper electrode 2 and the lower electrode 3, which are arranged in parallel, are tilted at a steep angle, water droplets condensed on the lower surface of the upper electrode will easily flow, even if the upper electrode and the lower electrode are exactly the same size. Also, drops falling from the lower end of the upper electrode will not fall on the object to be dried. Furthermore, water droplets are less likely to fall from the lower surface of the upper electrode, and the possibility of spark generation is accordingly reduced. Even so, there remains a risk that relatively large water droplets may move on the lower surface of the upper electrode, and sparks may occur at this time. In any case, the material to be dried cannot be stably placed on the steeply inclined lower electrode. Therefore,
If the upper and lower electrodes are simply tilted slightly, droplets from the lower surface of the upper electrode will stain the material to be dried or generate sparks, just as in the case of the upper and lower electrodes being in a horizontal position. Even if the water drops fall from the lower end of the upper electrode, sparks are generated between these water droplets and the object to be dried.

In contrast, in the invention of the present application, the lower surface of the upper electrode is made rough and the lower end of the upper electrode is extended outward, thereby making the upper and lower electrodes slightly inclined, thereby preventing spark generation and droplets. Therefore, there is no risk of defective products being produced. The inclination angle α of the upper and lower electrodes is approximately 5°, which allows even slippery items such as loose items to be placed stably. Further, the extension dimension X of the upper electrode that extends outward from the lower electrode does not need to be particularly large, and the distance between the water droplet falling from the lower side end 2a and the surface of the object to be dried must be a dimension that does not cause sparks. It's fine if you can get it.

The present invention can be applied to sucking and depressurizing the air inside a closed container and discharging at least the water vapor generated inside.
More effective drying can be achieved by reducing the pressure to around 100 torr and lowering the boiling point.

[Effect of idea]

According to the present invention, objects to be dried such as cheese after dyeing can be stably placed on the lower electrode, and some of the water vapor generated from the objects to be dried condenses on the lower surface of the upper electrode. However, water droplets do not grow into large droplets due to the rough lower surface of the upper electrode, but flow due to the slight inclination of the upper electrode and fall from the lower side edge of the upper electrode away from the object to be dried. ,
Droplets do not fall onto the object to be dried, and generation of sparks between the upper electrode and the object to be dried can be reliably prevented. This eliminates the occurrence of defective products such as burnt objects caused by sparks and stains caused by water droplets, and also eliminates problems such as work interruptions and equipment damage caused by sparks, and allows for efficient drying work. can be done.

[Brief explanation of drawings]

The attached drawings are for explaining the structure for preventing spark generation in the high frequency vacuum dryer of the present invention, and FIG. 1 is a side view conceptually showing the present invention, and FIG.
The figure is a front view, FIG. 3 is a front view showing one embodiment, and FIG. 4 is a vertical side view of the embodiment shown in FIG. 3.
It is. DESCRIPTION OF SYMBOLS 1... Sealed container, 2... Upper electrode, 2a... Lower side end, 3... Lower electrode, 3a... Lower side end, 4
...Vacuum generator, 11...High frequency generator.

Claims (1)

[Scope of utility model registration request] An upper electrode 2 fixed in a closed container 1 that can suck the air inside and reduce the pressure using a vacuum generator.
and a lower electrode 3 which is movable in and out of the sealed container and directly faces the above-mentioned upper electrode 2 inside the sealed container, and the lower electrode 3 on which the material to be dried A is placed outside the sealed container is moved into the sealed container. In a high-frequency vacuum dryer that uses high-frequency heating to dry the object A that is not in contact with the upper electrode 2, the upper electrode 2 and the lower electrode 3 are used to stably place the object A on the lower electrode. The lower electrode 2 is tilted horizontally with respect to the direction of movement of the lower electrode at a slight angle that allows the lower electrode to be placed. A structure for preventing generation of sparks in a high frequency vacuum dryer, characterized in that a lower side end 2a of the upper electrode 2 extends further outward than a lower side end 3a of the lower electrode 3 facing directly.