WO2013042959A2

WO2013042959A2 - Vacuum drying apparatus

Info

Publication number: WO2013042959A2
Application number: PCT/KR2012/007545
Authority: WO
Inventors: 전영준; 이민철
Original assignee: 주식회사 테라세미콘
Priority date: 2011-09-22
Filing date: 2012-09-20
Publication date: 2013-03-28
Also published as: TW201321696A; WO2013042959A3

Abstract

Disclosed is a vacuum drying apparatus. The vacuum drying apparatus according to the present invention dries an object using a pressure difference and heat, thus enabling the solvent mixed with a coating liquid coated on the object to be excellently dried. When a large amount of solvent is dried, a coating liquid may be hardened to the core thereof, and therefore, problems of the coating liquid leaning to one side or of generating pores caused by the solvent remaining at the coating liquid may be reduced. Consequently, reliability of the dried object can be improved. In addition, a connector is arranged in a housing to transmit power from an external source to a heater installed within the housing, and the space between the connector and the housing is completely sealed to achieve further excellent efficiency in drying the solvent mixed with the coating liquid coated on the object.

Description

Vacuum drying equipment

The present invention relates to a vacuum drying apparatus for drying a solvent contained in a coating liquid applied to a substrate by using vacuum and heat.

A coating liquid such as a photoresist is applied to a substrate for a flat panel display device used in an LCD (Liquid Crystal Display), an OLED (Organic Light Emitting Diodes) display, or a field emission display (FED). At this time, when the substrate is transferred in a state where the coating liquid applied to the substrate is not cured, a phenomenon occurs that the coating liquid is concentrated to one side.

In order to solve this problem, a solvent such as a solvent is mixed with the coating liquid and then applied, and then the solvent is dried to temporarily harden the coating liquid, and then the substrate is transported, thereby preventing the coating liquid from being oriented to one side.

By the way, in order to temporarily harden a coating liquid, a solvent should be dried. For this reason, a vacuum drying apparatus for forcibly drying and removing a solvent contained in the coating liquid by using a pressure difference has been developed and used.

In general, the vacuum drying apparatus has a lower housing and an upper housing which are coupled to each other to form a chamber which is a closed space in which the substrate is loaded and dried. The lower housing is fixed, and the upper housing is installed to be elevated on the upper side of the lower housing. When the upper housing is lowered and coupled to the lower housing to be sealed, the chamber is formed between the lower housing and the upper housing.

In the conventional vacuum drying apparatus, a solvent such as a solvent is dried using only a pressure difference, so that the drying efficiency of the solvent is lowered.

In detail, after applying a coating liquid containing 12.5 g of a solvent mixed on a second generation substrate of 370 mm x 470 mm, the pressure of the chamber was maintained at 10 torr and dried under reduced pressure for 5 minutes.

At this time, the amount of the dried solvent is calculated by comparing the weight difference between the weight of the substrate before drying and the weight of the substrate after drying, the difference between the weight before drying the substrate and the weight after drying is the difference between the solvent mixed in the coating liquid There is only a factor due to drying.

Table 1

Table showing amount of solvent dried in conventional vacuum drying apparatus

Chamber pressure (torr)	Drying time (min)	Amount of solvent mixed in the coating liquid (g)	Amount of dried solvent (g)
10	5	12.5	0.42

As shown in Table 1, the solvent mixed in the coating liquid was dried by about 3.36% and discharged. That is, when the solvent is dried using a conventional vacuum drying apparatus, the ratio of the dried solvent to the mixed solvent is 15% or less.

This means that the inside of the coating liquid is not cured, so that the inside of the coating liquid is concentrated on one side, and pores are generated due to the solvent remaining in the coating liquid. There was a disadvantage of deterioration.

Prior art related to vacuum drying apparatus is disclosed in Korea Patent Publication No. 10-2011-0077338.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to dry a large amount of solvent by using a vacuum and heat, vacuum drying that can improve the reliability of the product to be dried In providing a device.

Another object of the present invention is to provide a vacuum drying apparatus capable of further improving the drying efficiency by completely sealing between a connector and a housing connected to a heater to transfer external power to the heater.

Vacuum drying apparatus according to the present invention for achieving the above object, the main body; A housing installed in the main body and forming a chamber in which the loaded dry body is dried by a pressure difference; And a heater installed inside the housing to heat the dry object.

Since the vacuum drying apparatus which concerns on this invention dries a to-be-dried body using a pressure difference and heat, the drying rate of the solvent mixed with the coating liquid apply | coated to the to-be-dried body is excellent. When a large amount of the solvent is dried, the coating liquid is cured to the inside, thereby reducing the problem that the coating liquid is concentrated to one side or the pores due to the solvent remaining in the coating liquid. Therefore, there is an effect of improving the reliability of the product to be dried.

In addition, since a connector is installed in the housing for transmitting external power to the heater installed inside the housing, and the seal is completely sealed between the connector and the housing, the drying efficiency of the solvent mixed in the coating liquid applied to the dry object is more excellent. It works.

1 is a perspective view of a vacuum drying apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of the housing shown in FIG. 1. FIG.

3 is an exploded perspective view of FIG. 2;

4 is a bottom perspective view of FIG. 3.

5 is an enlarged perspective view of the heater shown in FIG.

6 is a cross sectional view of FIG. 2.

7 is an enlarged view of a portion “A” of FIG. 6.

8 is an enlarged view of a portion “B” of FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION The following detailed description of the invention refers to the accompanying drawings that illustrate specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention. It is to be understood that the various embodiments of the invention, although different from one another, need not be mutually exclusive. For example, certain shapes, structures, and features described herein may be embodied in other embodiments without departing from the spirit and scope of the invention in connection with one embodiment. In addition, it is to be understood that the location or arrangement of individual components within each disclosed embodiment may be changed without departing from the spirit and scope of the invention. The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled. The length, area, thickness, and shape of the embodiments shown in the drawings may be exaggerated for convenience.

Hereinafter, with reference to the accompanying drawings will be described in detail a vacuum drying apparatus according to an embodiment of the present invention.

1 is a perspective view of a vacuum drying apparatus according to an embodiment of the present invention, Figure 2 is a perspective view of the housing shown in Figure 1, Figure 3 is an exploded perspective view of FIG.

As shown, the vacuum drying apparatus according to the present embodiment includes a main body 110 forming an appearance, and the housing 120 is installed inside the main body 110. In the housing 120, a chamber 120a, which is an enclosed space in which a to-be-dried object 50, such as a flat panel display substrate, is loaded and dried, is formed.

The to-be-dried body 50 is coated with a coating liquid such as a photoresist, and the coating liquid contains a solvent such as a solvent or the like. When the to-be-dried body 50 is loaded into the chamber 120a, the chamber 120a is decompressed to become a vacuum state, whereby the solvent contained in the coating liquid applied to the to-be-dried body 50 is forcibly dried by a pressure difference. And is discharged to the outside of the housing 120.

The housing 120 has a lower housing 121 fixed to the main body 110 and an upper housing 125 that is supported by a portion of the upper main body 110 of the lower housing 121 and is installed to be elevated. The upper housing 125 is elevated by driving means 130 such as a motor or a cylinder fixed to the main body 110.

When the upper housing 125 is lowered, the upper housing 125 and the lower housing 121 are coupled to seal to form a sealed chamber 120a. Then, when the upper housing 125 is raised, the upper housing 125 and the lower housing 121 is spaced apart, thereby opening the chamber 120a. When the chamber 120a is opened, the to-be-dried body 50 is loaded into the chamber 120a or unloaded from the chamber 120a.

In addition, one side of the main body 110 is provided with a pumping means (not shown) such as a vacuum pump for reducing the chamber 120a in a vacuum state when the chamber 120a is sealed. The pumping means is preferably in communication with the lower surface of the lower housing 121 and the upper surface of the upper housing 125 to uniformly dry the to-be-dried body 50 to depressurize the chamber 120a.

When the to-be-dried body 50 is loaded into the chamber 120a, when the to-be-dried body 50 contacts the inner lower surface of the lower housing 121, the to-be-dried body 50 is supported by a robot arm (not shown). When loading the 50 into the chamber 120a or unloading the to-be-dried body 50 from the chamber 120a, there is no gap between the to-be-dried body 50 and the lower surface of the lower housing 121, which is inconvenient. .

For this reason, a plurality of support pins 141 for supporting the to-be-dried body 50 spaced apart from the inner lower surface of the lower housing 121 are installed to be lowered below the lower housing 121.

The support pin 141 is coupled to the lower end of the elevating plate 143 (see FIG. 4) installed to be elevated on and under the lower housing 121 to elevate as the elevating plate 143 is elevated. The support pin 141 passes through the lower surface of the lower housing 121 to enter and exit the chamber 120a, and the to-be-dried body 50 is mounted and supported at the upper end thereof.

Since the support pin 141 is installed to be elevated, the support pin 141 may protrude upward from the lower surface of the lower housing 121 as necessary. Then, the space of the chamber 120a can be reduced as compared with the structure in which the support pin 141 always protrudes upward from the lower surface of the lower housing 121.

A support plate 145 (see FIG. 4) is fixed to a portion of the main body 110 below the lifting plate 143, and a driving means such as a motor or a cylinder for lifting up and down the lifting plate 143 is supported on the support plate 145. Is installed.

Since the support pin 141 penetrates the lower surface of the lower housing 121, the vacuum of the chamber 120a may leak through the lower portion of the lower housing 121 through which the support pin 141 penetrates. In order to prevent this, the outer side of the lower housing 121, the expansion pipe 147 (see Fig. 4) is installed.

When the solvent is dried using only the pressure difference, the drying rate of the solvent mixed in the coating liquid is low. For this reason, in the vacuum drying apparatus according to the present embodiment, the heater 160 is installed to dry the solvent using heat as well as a pressure difference.

The heater 160 will be described with reference to FIGS. 3 to 5. 4 is a bottom perspective view of FIG. 3, and FIG. 5 is an enlarged perspective view of the heater shown in FIG. 3.

As shown, the heater 160 is formed in a plate shape is installed inside the housing 120 and heats the dry object 50. More specifically, the heater 160 is installed on the inner lower surface of the lower housing 121 and the inner upper surface of the upper housing 125, respectively.

The heater 160 is formed by dividing a plurality of

unit heaters

160a, 160b, 160c,... Having a predetermined shape, and

unit heaters

160a, 160b, 160c,... .) Are each controlled independently. Each unit heater (160a, 160b, 160c, ...) can be controlled independently, can be heated to a different temperature for each part of the dry object 50, as needed.

Each unit heater (160a, 160b, 160c, ...) is the first protective plate 161, the second protective plate 163, the first protective plate 161 and the second protective plate 161 coupled to the first protective plate 161 and the second The coil 165 is interposed between the protection plates 163.

Each coil 165 of each unit heater (160a, 160b, 160c, ...) may be formed in a uniform form, or may be formed in a non-uniform form. In addition, the coil 165 may be formed of an incroid material that does not react with a solvent that is a solvent.

When the dry object 50 is dried using the vacuum drying apparatus according to the present embodiment using the pressure difference and heat, the amount of the solvent dried will be described.

Apply a coating liquid containing 12.5 g of a solvent mixed to a second generation substrate of 370 mm x 470 mm, and maintain the atmosphere temperature of the chamber at 30 to 80 ° C. while maintaining the chamber pressure at 10 torr. The dried bodies 50 were dried for 3 to 5 minutes each.

At this time, the amount of the dried solvent is calculated by comparing the weight difference between the weight of the dried object 50 before drying and the dried object 50 after drying, the weight before drying the dry body 50 and the weight after drying The difference is caused only by the drying of the solvent mixed in the coating liquid.

TABLE 2

Table showing the amount of solvent dried in the vacuum drying apparatus according to this embodiment

division	Chamber pressure (torr)	Amount of solvent mixed in the coating liquid (g)	Ambient temperature of chamber (℃)	Heating time (min)	Dry solvent (g)	Drying rate (%)
One	10	12.5	30	5	4.50	36.0
2			40	5	4.85	38.8
3			50	3	5.05	40.4
4				4	5.95	47.6
5				5	7.00	56.0
6			60	3	8.50	68.0
7				4	9.40	75.2
8				5	9.19	73.5
9			70	3	9.00	72.0
10				4	9.20	73.6
11				5	9.30	74.4
12			80	3	9.50	76.0
13				4	9.40	75.2
14				5	9.38	75.0

As shown in Table 2, the solvent was dried at 4.50 g when the atmosphere temperature of the chamber was 30 ° C. and the heating time was 5 minutes, and the solvent was dried at 4.85 g when the atmosphere temperature of the chamber was 40 ° C. and the heating time was 5 minutes. .

Then, the solvent was dried at 5.05 g, 5.95 g, and 7.00 g, respectively, when the chamber was heated at 50 ° C. for 3 minutes, 4 minutes, and 5 minutes, and the chamber temperature was 60 ° C. The solvents were dried 8.50 g, 9.40 g and 9.19 g, respectively, when maintained for 3 minutes, 4 minutes and 5 minutes, respectively.

Then, the solvent was dried at 9.00 g, 9.20 g, and 9.30 g, respectively, when the chamber was heated at 70 ° C. for 3 minutes, 4 minutes, and 5 minutes, and the chamber was heated to 80 ° C. The solvent was dried for 9.50 g, 9.40 g and 9.38 g, respectively, when maintained for 3 minutes, 4 minutes and 5 minutes, respectively.

That is, when drying the to-be-dried body 50 using the vacuum drying apparatus which concerns on a present Example, the drying rate of the said solvent was 36 to 76%, and the drying rate was excellent compared with the conventional vacuum drying apparatus.

Although not shown in Table 2, the drying rate is 35% or more even when the ambient temperature of the chamber is set to 20 ° C. under the same conditions, and the heating time is 1 minute under the same conditions. Came out.

In the case where the pressure of the chamber was set to 0.1 torr under the same condition, all of the conditions were lower than 10 torr. Thus, a better drying rate was obtained than shown in Table 2.

And, if the ambient temperature of the chamber is 80 ℃, it is obvious that the temperature of the heater 160 should be heated to a higher temperature.

In the vacuum drying apparatus according to the present embodiment, since the solvent is dried by vacuum and heat, the drying rate of the solvent is excellent. This means that the coating liquid applied to the to-be-dried body 50 is cured to the inside, so that the problem of pore generation due to the phenomenon that the coating liquid is concentrated to one side or the solvent remaining in the coating liquid is reduced.

Since the solvent is dried and discharged by heat as well as the temperature difference, the solvent may be condensed after evaporated by heat. Then, the condensed solvent may fall into the to-be-dried body 50 to damage the to-be-dried body 50.

In order to prevent this, the vacuum drying apparatus according to the present embodiment is configured such that the vaporized solvent is condensed at the side of the housing 120, and then may fall outside the outer surface of the dry object 50.

A configuration in which the solvent condensed falls outside the outer surface of the to-be-dried body 50 will be described with reference to FIGS. 6 and 7. 6 is a cross sectional view of FIG. 2, and FIG. 7 is an enlarged view of a portion “A” of FIG. 6.

As shown, the internal central side temperature of the housing 120 is formed higher than the internal side temperature. That is, the inner side surfaces of the lower housing 121 and the upper housing 125 are formed to be lower than the internal central temperature. This is possible because the coils 165 of the

unit heaters

160a, 160b, 160c,... Can be independently controlled.

Then, the vaporized solvent moves to the side surface of the housing 120 having a low temperature, and condenses if the side temperature of the housing 120 is less than or equal to the predetermined temperature. The solvent condensed on the side of the lower housing 121 is introduced into the lower surface of the inner side of the lower housing 121 and then discharged to the outside. At this time, since the condensed solvent introduced into the inner lower surface of the lower housing 121 may flow between the heater 160 and the lower housing 121, the heater 160 installed in the lower housing 121 may have a lower housing. It is preferable to be spaced apart from the inner lower surface of 121.

In addition, a fence 170 is formed on the inner side of the upper housing 125 to form the solvent condensed after vaporization, and the condensed solvent formed on the fence 170 is an inner side of the lower housing 121. And fall between the outer surface of the heater 160 and flow into the inner lower surface of the lower housing 121 and then discharged to the outside.

In order to prevent the to-be-dried body 50 from being damaged by the condensed solvent falling from the bottom surface of the fence 170, between the inner side of the lower housing 121 and the outer surface of the heater 160. It is preferable that the space | interval 121a is formed and the space | interval 121a and the lower end surface of the fence 170 oppose.

In addition, a guide path 122 having a groove-shaped cross section is formed on the inner lower surface of the lower housing 121 facing the gap 121a. Then, since the condensed solvent introduced into the inner lower surface of the lower housing 121 flows into the guide path 122 and is stored, movement along the inner lower surface of the lower housing 121 is prevented.

The guide path 122 is in communication with the pumping means for depressurizing the inside of the housing 120, and the condensed solvent stored in the guide path 122 is discharged to the outside of the lower housing 121 by the pumping means.

Thus, damage to the dry matter 50 is prevented by the solvent condensed after evaporation.

Reference numeral 124 in FIG. 7 is a sealing member sealing between the lower housing 121 and the upper housing 125.

The heater 160 receives external power to heat the dry object 50.

To this end, the housing 120 is provided with a connector 180 for transmitting external power to the heater 160. The connector 180 is installed through the housing 120, one side of which is located inside the housing 120 and connected to the coil 165 of the heater 160, and the other side of which is located outside of the housing 120. It is connected to the external power supply side.

Since the connector 180 penetrates the housing 120, the vacuum of the chamber 120a does not leak until the connector 180 and the housing 120 are sealed.

The vacuum drying apparatus according to the present embodiment is provided with a sealing means for sealing between the connector 180 and the housing 120, which will be described with reference to FIGS. 5, 6 and 8. 8 is an enlarged view of a portion “B” of FIG. 6.

As shown, the heater 160 is installed on the inner lower surface of the lower housing 121 and the inner upper surface of the upper housing 125, respectively, the heater 160 is a plurality of parts (160a, 160b, 160c, ... ...) and are controlled independently of each other. Therefore, the connector 180 is formed on the lower surface of the lower housing 121 and the upper surface of the upper housing 125 by the number of partitioned

portions

160a, 160b, 160c,... Of the heater 160. Each is installed through.

The sealing means is installed on the outer lower surface portion of the lower housing 121 in which the connector 180 is installed and the outer upper surface portion of the upper housing 125, respectively. For the sake of simplicity, FIG. 4 shows only one connector 180 penetrated through a lower surface of the lower housing 121.

A first through hole 123a and a second through hole 123b are formed on the lower surface of the lower housing 121.

The first through hole 123a is formed to be adjacent to the inner side of the lower housing 121 so that one side communicates with the inside of the lower housing 121, and the other side is positioned inside the lower housing 121. The second through hole 123b is formed to be adjacent to the outer side of the lower housing 121 so that one side is located inside the lower surface of the lower housing 121 to communicate with the other side of the first through hole 123a, and the other side is lower In communication with the outside of the housing 121. Therefore, the inside and the outside of the lower housing 121 communicate with each other by the first through hole 123a and the second through hole 123b which communicate with each other. At this time, the diameter of the second through hole 123b is larger than the diameter of the first through hole 123a.

The connector 180 includes a conductive wire 181 connected to the coil 165 of the heater 160 and an outer shell 183 surrounding and protecting the conductive wire 181, and the first through hole 123a and the second through hole. Pass 123b.

The sealing means includes a fixing member 191, a lifting member 193, a sealing member 195 and a support member 197.

The fixing member 191 is formed in a substantially cylindrical shape, and the outer peripheral surface of one side is inserted and coupled to the second through hole 123b, and the other side thereof is exposed to the outside of the lower surface of the lower housing 121. At this time, the outer diameter of one side portion of the fixing member 191 inserted into the second through hole 123b is smaller than the outer diameter of the other portion exposed to the outside of the lower housing 121. Then, an end surface 191a is formed at an interface between one side portion and the other side portion of the fixing member 191, and the end surface 191a has a lower surface of the lower housing 121 having the second through hole 123b formed thereon. Contact. The end surface 191a of the fixing member 191 and the lower surface of the lower housing 121 which are in contact with each other are welded. Therefore, between the fixing member 191 and the lower housing 121 is completely sealed. The connector 180 is inserted and supported on the inner circumferential surface of the fixing member 191.

Lifting member 193 is formed in a substantially cap shape, the inner peripheral surface is coupled to the outer peripheral surface of the other portion of the fixing member 191. The inner circumferential surface of the elevating member 193 and the outer circumferential surface of the fixing member 191 are formed with interlocking teeth (not shown). As the elevating member 193 rotates forward and backward, the elevating member 193 is fixed member ( Go along 191). The connector 180 passes through the elevating member 193.

The sealing member 195 is interposed between the other inner circumferential surface of the fixing member 191 and the outer circumferential surface of the connector 180.

The supporting member 197 is installed inside the elevating member 193 to elevate with the elevating member 193, and supports the sealing member 195 to be in close contact with the fixing member 191 and the connector 180. In detail, the inclined surface 191b is formed on the other inner circumferential surface of the fixing member 191 to have an inner diameter that increases toward the outside of the lower housing 121, and the sealing member 195 is interposed on the inclined surface 191b. .

The support member 197 protrudes from an inner circumferential surface of the ring-shaped support frame 197a and the support frame 197a on which the inner surface of the elevating member 193 is installed, and the inner circumferential surface of the fixing member 191 and the connector 180. It includes a tubular support tube (197b) is inserted between the outer peripheral surface for supporting the sealing member (195). Then, when the elevating member 193 is raised by rotating the elevating member 193, the supporting member 197 also rises together with the elevating member 193, so that the sealing member is supported by the supporting tube 197b of the supporting member 197. 195 is in close contact with the inner circumferential surface of the fixing member 191 and the outer circumferential surface of the connector 180. Therefore, the fixing member 191 and the connector 180 are firmly sealed. The connector 180 passes through the support member 197.

Since the vacuum drying apparatus according to the present embodiment dries the dry object 50 by the pressure difference and heat, the drying efficiency of the solvent is excellent. In addition, a connector 180 for transmitting external power to the heater 160 installed inside the housing 120 is installed through the housing 120, and a seal is completely sealed between the connector 180 and the housing 120. Therefore, the drying efficiency of the solvent is more excellent.

Although the present invention has been described with reference to the preferred embodiment by way of example, it is not limited to the above embodiment and should be made by those skilled in the art without departing from the spirit of the present invention. Many variations and modifications are possible. Such modifications and variations are intended to fall within the scope of the invention and the appended claims.

Claims

main body;

A housing installed in the main body and forming a chamber in which the loaded dry body is dried by a pressure difference;

And a heater installed inside the housing to heat the dry object.
The method of claim 1,

The housing includes a lower housing fixed to the main body, and an upper housing supported by the main body of the upper portion of the lower housing to be liftable and separated from the lower housing or coupled to the lower housing as the lifting and lowering is performed.

The heater is installed on the inner lower surface of the lower housing and the inner upper surface of the upper housing,

The to-be-dried body is coated with a coating liquid containing a solvent as a solvent,

And the solvent is dried by a pressure difference and heat.
The method of claim 2,

The heater is a vacuum drying apparatus, characterized in that formed in a plate shape.
The method of claim 3,

The heater is a vacuum drying apparatus, characterized in that a plurality of unit heaters having a predetermined shape is partitioned.
The method of claim 4, wherein

The unit heater is a vacuum drying apparatus, characterized in that each independently controlled.
The method of claim 5,

Each of the unit heaters comprises a first protective plate, a second protective plate coupled to the first protective plate and a coil interposed between the first protective plate and the second protective plate.
The method of claim 6,

And the coil of each unit heater has a uniform shape.
The method of claim 6,

And the coil of each unit heater has a non-uniform shape.
The method according to claim 7 or 8,

The material of the coil is a vacuum drying apparatus, characterized in that (Incroid).
The method of claim 9,

The pressure of the chamber is 0.1-10 torr,

The ambient temperature of the chamber is 20 ~ 80 ℃,

The dry object is a vacuum drying apparatus, characterized in that for heating for 1 to 5 minutes.
The method of claim 10,

And the inner side surface temperature of the lower housing and the upper housing is lower than the internal central temperature.
The method of claim 11,

The inner side of the upper housing is provided with a fence (Fence) is formed of the solvent condensed after vaporization,

The condensed solvent condensed on the fence is dropped between the outer surface of the heater and the inner side of the lower housing and is discharged to the outside of the lower housing.
The method of claim 12,

The heater installed in the lower housing is spaced apart from the inner lower surface of the lower housing,

A gap is formed between an inner side surface of the lower housing and an outer surface of the heater.

And a gap between the lower housing and the heater is opposite to a lower surface of the fence.
The method of claim 13,

An inner lower surface of the lower housing is formed with a guide path having a groove-shaped cross section through which the condensed solvent flowing from the fence and passing through the gap between the lower housing and the heater is introduced.

And the condensed solvent that has fallen to the inner lower surface of the lower housing is discharged to the outside of the lower housing by a pumping means for depressurizing the inside of the housing.
The method of claim 5,

One side of the housing is connected to each of the unit heaters partitioned through the housing and the other side is provided with a connector that is respectively connected to the external power source,

And a sealing means for sealing between the housing and the connector.
The method of claim 15,

The sealing means,

An inner surface of the connector is supported through, one side is inserted and coupled to the housing, the other side of the fixing member exposed to the outside of the housing;

A lifting member coupled to the other side of the fixing member to be liftable and passing through the connector;

A sealing member interposed between the other inner circumferential surface of the fixing member and the outer circumferential surface of the connector;

And a support member installed inside the elevating member to elevate together with the elevating member, the connector passes through and supports the sealing member to be in close contact with the fixing member and the connector.
The method of claim 16,

On the other inner circumferential surface of the fixing member is formed an inclined surface inclined in the form of increasing the inner diameter toward the outside of the housing,

The sealing member is interposed on the inclined surface,

The other outer peripheral surface of the fixing member and the inner peripheral surface of the elevating member is formed with teeth interlocking with each other,

And the elevating member is elevated along the fixing member as the elevating member rotates forward and backward.
The method of claim 17,

The support member is formed in a ring-shaped support frame provided on the inner surface of the lifting member, protruding from the inner peripheral surface of the support frame and inserted between the inner peripheral surface of the fixing member and the outer peripheral surface of the connector to support the sealing member. And a support tube.
The method of claim 18,

The housing communicates with the inside of the housing and is formed with a diameter larger than the diameter of the first through hole through which the connector passes, so that one side communicates with the first through hole and the other side communicates with the outside of the housing. And a second through hole in which one side of the fixing member is inserted and coupled.
The method of claim 19,

One side outer diameter of the fixing member is formed smaller than the other side outer diameter,

A cross section formed at an interface between one side portion and the other side portion of the fixing member contacts the outer surface of the housing in which the second through hole is formed.

A cross section of the fixing member in contact with each other and the outer surface portion of the housing are welded to the vacuum drying apparatus.