JPH0727474A - Vacuum dryer - Google Patents

Abstract

PURPOSE:To perform a fast, complete drying under a low-vacuum by coating a work supporting jig and/or a work container with a heat-resistant, waterproof membrane with a high infrared ray absorption, or forming it of a heat resistant, waterproof material with high infrared ray absorption. CONSTITUTION:A stand 5 is set up in a vacuum chamber 1 so that works 4 are placed in the middle between upper and lower infrared ray heaters 2. The table of the stand 5 is netted using stainless wire and its surface is coated with a waterproof, heat resistant membrane with a high infrared ray absorption. A work container 6 such as a bucket which contains the works 4 is put on the stand 5. As raw material of a reflector is excellent in heat conduction, the works 4 can be easily heated up to boiling point or higher when contact points to the work container 6 with a high infrared ray absorption are ensured. In the case the works 4 are of an absorber such as a resin film, moisture can be evaporated by direct heating alone.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to precision equipment such as printed circuit boards, hard disk and other electrical and electronic related equipment, brake parts, electrical equipment and other automobile and mechanical metal related equipment, camera parts and watch parts. The present invention relates to a vacuum drying device for drying optical equipment after washing with water, or for drying tableware such as cups and various washed products.

[0002]

2. Description of the Related Art Conventionally, when washing work pieces such as precision equipment parts, washing them with water and drying them, first, the work pieces are heated with hot air, and then quickly put into a low vacuum (inside and outside of 60 torr). The water was dried by lowering the boiling point of water to about 42 ° C. As another drying method, a technique of using far infrared rays to dry under low vacuum has been tried, but a printed circuit board or a film work which is a far infrared absorber is overheated. There is a problem that it can not be dried sufficiently because it can not continue to give heat because the far infrared rays are reflected in things such as aluminum parts which are far infrared reflectors. there were.

[0003]

The above conventional techniques have the following problems. Since the heated work gets stuck immediately, the drying was insufficient or the drying took too long. For example, if the work is a printed circuit board or a metal surface-treated work, the allowable heating temperature is 60 to 8
Since many of them are about 0 ° C., drying was extremely difficult. In the case of a coiled work, once water entered, it was difficult to remove it, so complete drying itself was almost impossible. Similarly, it was difficult to dry the contact surface between the work and the work container. Since hot air is sent to the work housed in the dryer to dry it, there is a high possibility that dust, etc. will rise up.
It was hard to say that clean dryness of ku could be obtained. In terms of cost, it was a very expensive device because it was necessary to incorporate a hot air manufacturing device. Since it was a vertical one-tank type vacuum dryer, it was not suitable for mass production.

As a result of various studies in view of the above points, the inventor of the present invention has continued to apply heat above the boiling point to various works under a low vacuum and supports jigs and / or works. In order to completely dry the work storage container at the same time, the jig for supporting the work and / or the work storage container is formed by coating with a heat-resistant and water-resistant film having a high infrared absorption capacity, or the infrared absorption capacity is increased. We decided to use high heat and water resistant materials. With this, at the same time as direct heating to the work by far infrared rays,
By conducting heat conduction heating from the jig and / or the work storage container that continues to absorb far infrared energy to the work that is difficult to transfer heat, it is possible to dry quickly and completely under low vacuum. It was done.

That is, the work of the radiant heat from far infrared rays and the heat conduction of heat from a jig and / or a work container having a high infrared absorption ability are simultaneously performed, and a work such as a coil is used. Far infrared rays are directly absorbed and boiled,
Water in the contact portion with the work container can be surely boiled and dried by heat conduction from the jig and / or work container having a high infrared absorption ability. Further, even if a far infrared ray non-absorbing material such as aluminum or stainless steel part mounted on a printed circuit board is not in direct contact with a jig and / or a work container having a high infrared absorption ability, By causing the far-infrared absorber, for example, the resin substrate portion of the printed circuit board, to conduct heat conduction heating to the non-absorber, the attached water can be surely boiled and dried.

Further, it is hard to say that the vertical type one-tank type drying device can sufficiently cope with the mass production system. Therefore, when it is necessary to perform a large amount of drying quickly, a horizontal type vacuum tank can be used instead of the conventional vertical type to store multiple work storage containers at the same time. It is designed to be compatible with.

[0007]

SUMMARY OF THE INVENTION A vacuum drying apparatus according to the present invention comprises a jig for supporting a work and / or a work container as an infrared ray in a vacuum chamber containing a far infrared heater. It is formed by coating with a heat-resistant and water-resistant film having high absorptivity or a heat-resistant and water-resistant material having a high infrared absorptivity. Further, the work container is formed of a metal basket having a large number of holes or meshes, and the surface of the basket is coated with a black heat-resistant and water-resistant paint.

Further, in the vacuum drying apparatus according to the present invention, the jig for supporting the work and / or the work container in the vacuum chamber is coated with a heat-resistant and water-resistant film having a high infrared absorption capability. Alternatively, it is formed of a heat-resistant and water-resistant material having a high infrared absorption capacity and a temperature detecting section is provided in the jig and / or the work container or in the vicinity of the jig and the container, and a signal of the detecting section is provided. Therefore, a control unit for controlling the surface temperature of the far infrared heater is provided. Further, the vacuum drying apparatus according to the present invention forms a jig for supporting a work in a vacuum chamber and / or a work container by coating with a heat-resistant and water-resistant film having a high infrared absorption ability, or A target value is set as an optimum drying temperature of a work in a vacuum chamber which is formed of a heat-resistant and water-resistant material having a high infrared absorption ability and is held so as to come into contact with the jig and / or the work container. It is equipped with a control unit for controlling the surface temperature of the heater as compared with the above. And, the vacuum drying device according to the present invention,
A vacuum chamber containing a far-infrared heater is formed in a horizontal type, and a plurality of work storage containers are arranged and stored in the vacuum chamber.

[0009]

First, the work is supported and stored in the vacuum chamber by the jig and / or the work storage container. Next, in a low vacuum, the far-infrared heater is heated to a preset temperature, and the far-infrared absorber and the water adhering to the work have far-infrared rays at an allowable temperature. Is absorbed directly. Simultaneously with the work as a far-infrared reflector, the jig and / or the work container having a high infrared absorption ability absorbs the permissible temperature on the surface under the same low vacuum. The temperature-controlled heat conduction heating from the jig and / or the work container is continuously performed. In this way, it becomes possible to continue accurately boiling water having a low boiling point under low vacuum. Then, for the first time, drying under low vacuum can be achieved quickly, cleanly, and at low running cost.

In order to control the surface temperature of the far-infrared heater, the signal from the temperature detecting portion provided in the jig and / or the work container is used to control the surface temperature of the far-infrared heater. To prevent the jig and / or the work container from being overheated, and the far infrared heater
Is controlled by PID control or the like. However, even when the heating switch of the far infrared heater is off, far infrared rays are still radiated from the surface of the far infrared heater, so that the jig and / or the work container cannot be far away. Since infrared rays are received, it is necessary to control the surface temperature of the far infrared heater in consideration of these thermal energies.

As another means for controlling the surface temperature of the far-infrared heater, the optimum drying temperature of the work in the vacuum tank held so as to come into contact with the jig and / or the work storage container is set. Measure in advance and determine the target value for each work. In this way, the predetermined target value is input to the control unit, and the target temperature is compared and calculated to control the surface temperature of the heater by the control unit that performs PID control or the like. Also in this case, as described above, it is necessary to control in consideration of the fact that the far infrared ray is still radiated from the surface of the far infrared ray heater even when the heating switch of the far infrared ray heater is turned off. There is. It goes without saying that the vacuum chamber according to the present invention can be applied to both the vertical type and the horizontal type.

On the other hand, if drying is carried out in the same manner as described above to make the vacuum tank horizontal and at the same time accommodate a plurality of work storage containers, the time required for drying per one vacuum tank is almost the same. Therefore, the processing time for each work storage container is shortened by a division formula according to the number of work storage containers.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings by taking a vertical vacuum chamber as an example. As shown in FIG. 1, the far infrared heater-2 and the reflecting plate 3 are set and attached to the ceiling and bottom of the vacuum chamber 1 made of stainless steel or the like in FIG. The shape of the far-infrared heater-2 is such that one heater is meandered to form a continuous shape as in this example, or linear heaters are attached in parallel. May be law. And the work 4 is the upper and lower far infrared rays.
The pedestal 5 is set in the vacuum chamber 1 at a position such that it is exactly in the center of the computer-2. The pedestal 5 is made of a wire of stainless steel or the like, and the pedestal portion is formed in a mesh shape, and the surface thereof is covered with a heat-resistant and water-resistant film having a high infrared absorption ability such as a water-resistant heat-resistant paint. A work storage container 6 such as a basket for storing the work 4 is placed on the pedestal 5. 2, 7 is a lid of the vacuum chamber 1, 8 is a handle thereof, 9 is an intake port to a vacuum pump (not shown), 10 is a vacuum meter, 11 is an air supply port,
Reference numeral 12 denotes an outlet for electric wiring in which the periphery of the wiring is sealed using a rubber plug, and 13 denotes a drain for discharging water or the like to the outside.

As shown in FIGS. 3A to 3D, the work container 6 is manufactured according to the shape of the work 4, and is formed into a mesh shape with a metal such as stainless steel or other rigid material. Alternatively, the surface of the container in which a large number of holes are punched is formed by coating with a heat-resistant and water-resistant film having a high infrared absorption capacity such as a water-resistant heat-resistant paint, or the entire container is made of an infrared absorption capacity such as ceramics. A far-infrared ray can be efficiently and quickly absorbed by being formed of a highly heat-resistant and water-resistant material, so to speak, it is preferable to form a black body that completely absorbs all the incident radiant energy, but it is not necessarily limited to this. What is essential is that the far infrared energy absorption ability is high and the absorbed heat can be quickly transmitted to the work 4 by heat conduction. Figure 3 (a)
Shows a case where the work 6 of the aluminum HDD motor base, which is a reflector, is held in the work storage container 6 having a recessed central portion. FIG. 3 (b) contains various materials. FIG. 3 (c) shows the case where the work 6 of the printed circuit board is held through the jig 6a, and the work 6 of the FDD part of the composite part of aluminum, copper coil and film is held. If you do,
Fig. 3 (d) shows a glass cup work 6 which is a high-rate absorber.
, Respectively, are shown.

In order to prevent the work 4 from being overheated, a temperature detecting portion serving as a heat sensitive portion is provided in a work container 6 such as a basket located near the work 4 as shown in FIG. 13 is set in a black body like the work container 6.
Electric control is performed by electric wiring as shown in FIG. 4, but this is an example and the wiring method is not limited. Set the work 4 so that it is not overheated. Out of FIG.
ELB is an earth leakage breaker, MC is an electromagnetic contactor, PB / L is an illuminated push button switch, F is a plug-type fuse, SCR is a power regulator, ATC is a temperature controller, and TC is a thermocouple.

With this structure, as shown in FIG. 5, the far infrared rays emitted from the upper and lower far-infrared line heaters-2 are reflected or absorbed by the absorptance of the material of each work 4. However, since it is almost reflected by the aluminum material, it is almost impossible to heat the aluminum material. Therefore, first, far-infrared heating is performed on the work container 6 having a high infrared absorption capacity, such as a basket, and the aluminum material is heated from the work container 6 by heat conduction heating.

Since the reflector material is excellent in heat conductivity, it can be easily heated above the boiling point temperature if only a small contact point with the work container 6 having a high infrared absorption capacity such as a basket is secured. Like On the other hand, when the work 4 is an absorber such as a resin film, the far-infrared ray heating is directly performed, so that the water can be evaporated only by directly heating the far-infrared ray.

In this embodiment, the vacuum degree is set to about 60 tons.
Therefore, the boiling point is about 42 ° C. In this case, in order to completely evaporate the water adhering to the work container 6 having a high infrared absorption capacity such as the work 4 and the basket,
Work at a temperature of 50 ° C to 60 ° C at all times without excess or deficiency
It is necessary to give the temperature detecting section 13 which is a heat-sensitive section to a black body having a high infrared absorption ability,
Since the jig 6a near the work 4 and / or the work storage container 6 or the jig 6a and the position in contact with the storage container 6 are provided, sufficient control can be performed. In other words, work 4
Whether it is a single material or a composite material, it can be dried regardless of the material.

Further, when the work 4 is dried in the vacuum tank 1, the inside of the vacuum tank 1 is held so as to come into contact with the jig 6a and / or the work container 6 for each work 4. The War
The optimum drying temperature of C4 is measured in advance, and the measured temperature is set as a target value. Then, the surface temperature of the heater is controlled by PID control or the like so as to maintain the surface temperature of the heater at an optimum temperature by comparing with a target value determined according to the corresponding work 4, or the work 4 is overheated. A control unit (not shown) for controlling by PID control or the like to prevent such a situation may be provided.

By making the vacuum chamber 1 horizontal as shown in FIG. 6, the production efficiency is greatly improved. In this embodiment, a structure for accommodating the work storage containers 6 such as three baskets is used. However, in the vacuum chamber 1 having the same diameter, one basket or the like is accommodated in the vertical vacuum chamber 1. Compared with the structure that can store the container 6, the difference in drying time is only about 10 seconds to bring the vacuum degree of 60 torr, so in this case, the efficiency of the horizontal type is vertical type. It can be seen that it is about three times as large as that of the vacuum chamber 1. All can be automated, and the shape of the tank can be various shapes such as a rectangular parallelepiped box shape, an elliptic cylinder shape, and a kamaboko shape. Further, although a case is shown in which both sides of the horizontal vacuum chamber 1 have a vertical opening / closing structure, the structure is not necessarily limited to this, and only one side may have an opening / closing structure. Due to the horizontal vacuum chamber 1 structure,
It has a significant effect in realizing line production with low-cost equipment, which was not possible with conventional vacuum drying processes.

[0021]

As described above, according to the vacuum drying apparatus of the present invention, the work directly absorbs far infrared rays,
Since it can be heated by heat conduction from a heat and water resistant jig and / or a work container that has a high infrared absorption capacity, any work can be done quickly and reliably regardless of various materials. As it can be completely dried by heating and its temperature can be perfectly controlled and maintained until the water is completely evaporated, compared to the conventional dryer, a water dryer with a wide range of use is available with significantly superior effect and low cost. Can be provided. Further, since the surface temperature of the far-infrared heater is controlled by the control unit, the work is released from insufficient heating or overheating, and a stable dried product can be reliably obtained. Further, the present invention can be applied to both a vertical type and a horizontal type, but when it is necessary to dry a large amount of work quickly, the vacuum type can be changed to a horizontal type. By doing so, a plurality of work storage containers can be put in at one time, and mass production system can be supported.

[Brief description of drawings]

FIG. 1 is a plan view showing a set example of a far infrared heater and a reflection plate.

FIG. 2 is an explanatory diagram showing an example of a schematic structure in a vertical vacuum chamber.

3 (a) to 3 (d) are side views showing an example of storing various works in a work container.

FIG. 4 is a wiring diagram showing an example of electric wiring.

FIG. 5 (a) is a perspective view of a work storage container coated with a heat-resistant and water-resistant film having high infrared absorption ability, and FIG. 5 (b) shows an example of far infrared absorption / reflection action and heat conduction action. It is an explanatory view shown.

6A is a perspective view showing an embodiment of a horizontal vacuum chamber, FIG. 6B is a side sectional view, and FIG. 6C is a vacuum chamber sectional view.

[Explanation of symbols]

1 Vacuum Tank 2 Far Infrared Heater 4 Work 5 Stand 6 Work Storage Container 6a Jig 13 Temperature Detector

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] September 16, 1994

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title of invention Vacuum drying device

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to water for precision and optical related equipment such as printed circuit boards, electric / electronic related equipment such as hard disks, brake parts, electric parts and other automobile / mechanical metal related equipment, camera parts, watch parts and the like. The present invention relates to a vacuum drying device for drying various washed products after washing.

[0002]

2. Description of the Related Art Conventionally, when a work such as a precision instrument part is washed and then washed with water to be dried, the work is first heated by hot air, then quickly made into a low vacuum to lower the boiling point of water to dry the work. It was Also, as another drying method, a technique of drying in a low vacuum by using far infrared rays has been attempted, but a printed circuit board that is a far infrared absorber or a film-like work is overheated too much. There was a problem that it could not be given enough damage and could not be dried sufficiently because it could not continue to give heat because things such as aluminum parts that are far infrared reflectors reflect far infrared rays. .

[0003]

The above conventional techniques have the following problems. Since the heated work quickly gets stuck, the drying is insufficient or the drying takes too long. For example, when the work is a printed circuit board or a metal part whose surface is treated, the allowable heating temperature is 60 to 8
Since many of them are about 0 ° C., drying was extremely difficult. In the case of a coiled work or the like, once water entered, it was difficult to remove it, so complete drying itself was almost impossible. Similarly, it is difficult to dry the contact surface between the work and the work storage container. Since hot air is sent to the work stored in the dryer to dry the work, dust and the like are likely to fly up, and it is difficult to say that the work can be dried cleanly.

As a result of various studies in view of the above points, the present inventor has continued to apply heat above the boiling point to various works under a low vacuum, and at the same time, a jig for supporting the works and / or a work storage container can be perfect. In order to dry, the jig for supporting the work and / or the work storage container is formed by coating with a heat-resistant and water-resistant film having high infrared absorption ability, or formed by heat-resistant and water-resistant material having high infrared absorption ability. did. As a result, at the same time as directly heating the work with far infrared rays,
By conducting heat conduction heating from the jig and / or the work storage container that continues to absorb far infrared energy to the work, rapid and complete drying under low vacuum is made possible for the first time. That is, radiant heating from far infrared rays and heat conduction heating from a jig and / or a work storage container having a high infrared absorption capability are simultaneously performed on the work.

[0005]

A vacuum drying apparatus according to the present invention comprises a jig for supporting a work and / or a work storage container in a vacuum chamber having a far-infrared heater built therein, which has high heat and water resistance with high infrared absorption capability. It is formed of a heat-resistant or water-resistant material having a high infrared absorbing ability.

[0006]

Operation: First, the jig and / or the work container is used to support and store the work in the vacuum chamber. Next, in a low vacuum, the far-infrared heater is caused to generate heat so as to reach a preset temperature, and the work as the far-infrared absorber and water adhering to the work directly absorbs the far-infrared ray at the allowable temperature. Simultaneously, under the same low vacuum, the surface of the jig and / or the work storage container is allowed to absorb the permissible temperature so that the surface of the jig and / or the work which is the far infrared reflector can be absorbed. Alternatively, the temperature controlled heat conduction heating from the work storage container is continuously performed. In this way, it becomes possible to continue accurately boiling water having a low boiling point under low vacuum. Then, for the first time, drying under low vacuum can be achieved quickly, cleanly, and at low running cost.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the far-infrared heater 2 and the reflection plate 3 are set and attached to the ceiling and bottom of the vacuum chamber 1 made of stainless steel or the like in FIG. And work 4
The pedestal 5 is set in the vacuum chamber 1 at a position such that is located exactly in the center of the far infrared heaters 2 above and below. Stand 5
Is formed by using a wire such as stainless steel to form a pedestal in a mesh shape, and the surface thereof is covered with a heat-resistant and water-resistant film body having a high infrared absorption capacity such as a water-resistant heat-resistant paint. A work storage container 6 such as a basket for storing the work 4 is placed on the pedestal 5. In FIG. 2, 7 is the lid of the vacuum chamber 1, 8 is its handle, and 9
Is an intake port to a vacuum pump (not shown), 10 is a vacuum meter, 11 is an air supply port, 12 is an electric wiring outlet for sealing the wiring around with a rubber stopper, and 13 is a temperature detecting part which is a heat sensitive part. Parts are shown respectively.

With this structure, the far infrared rays radiated from the upper and lower far-infrared ray heaters 2 are reflected or absorbed depending on the absorptivity of the material of each work 4, as shown in FIG. However, since it is almost reflected by the aluminum material, it is almost impossible to heat the aluminum material. Therefore, first, far-infrared heating is performed on the work storage container 6 having a high infrared absorption capacity such as a basket, and the aluminum material is heated from the work storage container 6 by heat conduction heating.

Since the reflector material is excellent in heat conductivity, it is possible to easily heat it above the boiling point temperature if only a small contact point with the work container 6 having a high infrared absorption capacity such as a basket is secured. Become. On the other hand, when the work 4 is an absorber such as a resin film, since far-infrared heating is directly performed, water can be evaporated only by direct heating of far-infrared radiation.

Since the vacuum degree setting in this embodiment is about 60 Torr, the boiling point is about 42.degree. In this case, in order to completely evaporate the water adhering to the work storage container 6 having a high infrared absorption capacity, such as the work 4 and the basket,
Work piece 4 without excess or deficiency at a temperature of 50 to 60 ° C at all times
It is necessary to provide the jig 6a near the workpiece 4 and / or the workpiece storage container 6 or the jig 6a thereof by forming the temperature detecting portion 13 which is a heat sensitive portion into a black body having a high infrared absorption ability. Since it is provided at a position in contact with the storage container 6, sufficient control can be performed.

When drying the works 4 in the vacuum chamber 1, optimum drying of the works 4 in the vacuum chamber 1 held so as to contact the jig 6a and / or the work container 6 for each work 4. The temperature is measured in advance, and the measured temperature is set as the target value. Then, PID control is performed to maintain the surface temperature of the heater at an optimum temperature by comparing with a target value determined according to the corresponding work 4, or PID control for controlling the work 4 not to be overheated. You may make it provide the control part (not shown) controlled by etc.

[0012]

As described above, according to the vacuum dryer of the present invention, in addition to the case where the work directly absorbs far infrared rays,
Since it can be heated by heat conduction from the heat- and water-resistant jig and / or work storage container with high infrared absorption capacity, any work can be swiftly and reliably completely dried, regardless of various materials. As a result, the temperature can be perfectly controlled and maintained until the water is completely evaporated, and as a result, it is possible to provide a water drying device with a wide range of use, with a significantly superior effect and a low price compared to conventional drying devices. it can.

[Brief description of drawings]

FIG. 1 is a plan view showing a set example of a far infrared heater and a reflection plate.

FIG. 2 is an explanatory diagram showing an example of a schematic structure inside a vacuum chamber.

FIG. 3 is an explanatory diagram showing an example of far infrared absorption / reflection action and an example of heat conduction action.

[Explanation of symbols] 1 vacuum tank 2 far infrared heater 4 work 5 stand 6 work storage container 6a jig

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

[Figure 3]

Claims (5)

[Claims] 1. A vacuum tank having a built-in far-infrared heater is formed by coating a jig for supporting a work and / or a work storage container with a heat-resistant and water-resistant film having high infrared absorption ability. Or a vacuum drying apparatus characterized by being formed of a heat resistant and water resistant material having a high infrared absorption ability. 2. The work storage container is formed of a metal basket having a large number of holes or meshes, and the surface of the basket is coated with a black heat-resistant and water-resistant paint. The vacuum dryer described. 3. A jig for supporting a work in a vacuum chamber and / or a work container is formed by coating with a heat-resistant and water-resistant film having a high infrared absorption ability, or a heat resistance having a high infrared absorption ability. , A temperature detecting part formed of a water resistant material and provided in the jig and / or the work container or in the vicinity of contact with the jig and the container, and the surface of the far infrared heater by the signal of the detecting part. A vacuum drying apparatus comprising a control unit for controlling temperature. 4. A jig for supporting a work in a vacuum chamber and / or a container for holding a work is formed by coating with a heat-resistant and water-resistant film having a high infrared absorption ability, or a heat resistance having a high infrared absorption ability. , A target value is set as an optimum drying temperature of the work in the vacuum tank which is formed of a water resistant material and is held so as to come into contact with the jig and / or the work storage container, and is compared with the target value. A vacuum drying apparatus comprising a control unit for controlling the surface temperature of the turbine. 5. A vacuum chamber having a built-in far-infrared heater is formed horizontally, and a plurality of the work storage containers according to claim 1 are stored side by side in the vacuum chamber. 1,
The vacuum drying device according to 2, 3 or 4.