JPH10170152A - Drying device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a drying device in which a fan for introducing fresh air can be dispensed with. SOLUTION: In a drying device 21 (41) provided with a nozzle arranged in a drying chamber 22, an air discharge passage 24 extended from the drying chamber 22 to the outside, a circulation passage 25 to be communicated with the drying chamber 22, an air blowing passage 26 to be communicated with the nozzle, a fan 27 arranged between the circulation passage 25 and the air blowing passage 26, and a fresh air introducing passage 29 provided with a filter 10 and connected to the circulation passage 25, a damper 33 for regulating the circulation air volume is arranged on the upstream side of a connection part A (B) to the fresh air introducing passage 29 having no forced draft fan in the circulation passage 25.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for introducing fresh air into a drying device.

[0002]

2. Description of the Related Art Conventionally, as shown in FIGS. 5 and 6, a drying apparatus 1 has a drying chamber 2 through which a web W such as running paper or plastic film passes, and a box-shaped drying apparatus 2 disposed inside the drying chamber 2. , An exhaust path 4 extending from the inside of the drying chamber 2 to the outside, a recirculation path 5 formed in the drying chamber 2, a blowing path 6 communicating with the nozzles 3, 3,. A blower fan 7 and a heating device 8 arranged between the blower passage 6 and the return passage 5
And a fresh air introduction passage 9 joined to the air passage. The fresh air introduction passage 9 includes a filter 10, a pushing fan 11, and a damper 13 for adjusting the amount of fresh air, and forcibly blows fresh air taken in from the outside to the blowing fan 7. The exhaust path 4 is provided with an exhaust fan 12 and an exhaust air amount adjusting damper 14 at appropriate locations.

[0003] The hot air blown by the blower fan 7 and heated by the heating device 8 is guided to each nozzle 3 by a blower path 6 and blows out from each nozzle 3 toward the web W, contributing to the drying of the web W. After that, it is circulated so as to be guided by the return path 5 and return to the blower fan 7. Part of the circulating hot air is exhausted in the exhaust passage 4 and replaced with fresh air introduced in the fresh air introduction passage 9 in order to prevent an increase in the solvent vapor pressure due to drying of the solvent.

When the drying capacity of the drying apparatus 1 is high, all or most of the hot air ejected from the nozzles 3, 3,... Is exhausted from the exhaust path 4 to the outside, and fresh air corresponding to the exhaust air amount is supplied to the fresh air introduction path. It is necessary to use so-called full exhaust introduced in step 9. Therefore, the conventional drying device 1 is provided with a blower fan 11 and a fresh air amount adjusting damper 13 in the fresh air introduction passage 9 to forcibly remove a predetermined amount of fresh air from the return passage 5.
To be supplied.

[0005] If the blower fan 11
Is not provided, the fresh air does not pass through the filter 10 having a high airflow resistance, but passes through the web entrances 2a and 2b of the drying chamber 2 having a low airflow resistance, and is guided to the recirculation path 5 to blow air fan 7. It will be sucked into. In this case, air that does not pass through the filter 10 is introduced, so that there is a problem that clean drying cannot be achieved, and a problem that stable running of the web W is hindered by a high-speed air flow passing through the web entrances 2a and 2b. Will also occur. Therefore, in the conventional drying apparatus having a high drying capacity, the blowing fan 1 is inserted into the fresh air introduction passage 9 having the filter 10.
One had to be provided.

[0006]

However, the provision of the blower fan 11 in the fresh air introduction passage 9 requires the use of the blower fan 11.
This leads to an increase in manufacturing cost and operating cost.

Therefore, an object of the present invention is to provide a drying apparatus which does not require a blower fan for introducing fresh air in order to solve the above problem. Further, claim 2
The described invention aims to provide a drying device in which the structure for introducing fresh air is simplified.

[0008]

The gist of the present invention is that a nozzle disposed in a drying chamber, an exhaust path extending from the drying chamber to the outside, a return path leading to the drying chamber, In a drying apparatus provided with a blower passage leading to a nozzle, a blower fan disposed between the return passage and the blower passage, and a fresh air introduction passage provided with a filter and joined to the return passage, the return passage is pushed in. A drying apparatus characterized in that a circulating air volume adjustment damper is disposed upstream of a junction with the fresh air introduction path without a fan.

According to the first aspect of the present invention, fresh air can be forcibly guided from the fresh air introduction passage to the blow fan by the suction force of the blow fan. Therefore, when the circulating air volume adjusting damper is fully closed, all of the hot air ejected from the nozzles can be discharged to the outside from the exhaust path, and fresh air having the same amount as the exhaust air volume can be discharged from the fresh air introduction path through the return path. It can be forcibly guided to the blower fan, and the exhaust can be exhausted entirely. In addition, when the circulation air flow rate damper is opened, a portion of the hot air blown from the nozzle and fresh air can be forcibly guided to the blower fan via the return path according to the opening degree, and the fresh air The same amount of exhaust can be discharged from the exhaust path to the outside.

The gist of the present invention described in claim 2 is as follows.
The drying apparatus according to claim 1, wherein the blower fan is provided in a fan installation chamber formed integrally with the drying chamber, a partition wall is provided between the drying chamber and the fan installation chamber, and a suction port is provided in the partition wall. And the fresh air introduction passage is opened in the space between the partition wall and the suction port of the blower fan.

According to the second aspect of the present invention, since a part of the return path is formed in the space between the partition wall and the suction port of the blower fan, it is not necessary to form this part with a duct. .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A drying apparatus according to the present invention will be described below with reference to the embodiments shown in FIGS.

FIG. 1 schematically shows two types of drying devices 21 and 41 joined in series. FIG. 2 is a plan view of one of the drying devices 21 partially cut away and FIG. FIG. 4 is a front view in which one of the drying devices 21 is viewed from the front in the web traveling direction and partially cut away, and FIG. 4 is a plan view in which the other drying device 41 is partially cut away.

A common feature of the drying devices 21 and 41 is that, as shown in FIG. 1, a junction A of the return line 25 with a fresh air introduction passage 29 without a pushing fan.
(B) The circulating air volume adjustment damper 33 is disposed on the upstream side of (B). Further, as shown in FIGS. 1 to 3, a characteristic feature of the drying device 21 is that a partition wall 38 is provided between the drying chamber 22 and the fan installation chamber 37 and the partition wall 38 is provided.
Circulating air volume adjustment damper 33
Is disposed, the space C between the partition wall 38 and the suction port 27a of the blower fan 27 is made a part of the return path 25,
This means that the end 29a of the fresh air introduction passage 29 is opened in the space C.

The drying unit 21 has a drying chamber 22 through which a running web W such as paper or plastic film passes, and a fan installation chamber 37 in which a blower fan 27 and a heating device 28 are installed. , Both rooms 22,3
7 is partitioned by a partition wall 38 having a plate shape or the like. Blowing fan 2
7 is a fan casing 27 as shown in FIGS.
b, a fan rotor 27c built in a fan casing 27b, and a motor 2 for rotationally driving the fan rotor 27c.
7d, and the air sucked from the suction port 27a is sent to the heating device 28 with the rotation of the fan rotor 27c. The heating device 28 is appropriately selected from a steam heater, an oil heater, a gas burner, and the like, and is configured to heat the blown air to a set temperature.

As shown in FIG. 1 to FIG.
The air passage 26 extending through the partition wall 38 extends from the inside of the drying chamber 22 with a duct and is branched into two paths.
The branch passages 26a and 26b of the blower passage 26 are joined to each nozzle 3 so as to be able to ventilate, and are provided with dampers 39 and 39 for adjusting the amount of branching in the middle thereof as necessary.

The drying chamber 22 includes a recirculation passage 25 for recirculating hot air discharged from the nozzles 3, 3,.
And it is formed around the air passage 26 formed by the duct. The return path 25 extends through the suction port 38 a of the partition wall 38 to the space C.

The fresh air introduction passage 29 is connected to the filter 1
0, so that fresh air taken in from the outside is supplied to the space C. The exhaust path 24 is provided in the drying chamber 2
2 and is provided with an exhaust air volume adjusting damper 34 and an exhaust fan 32.

The hot air of the set temperature generated by the blower fan 27 and the heating device 28 is guided to each nozzle 3 through the blower passage 26, and blows out from each nozzle 3 toward the web W to dry the web W in a floating state. After contributing to the drying of the web W, the web W is guided through the recirculation path 25, a part of which is exhausted to the outside through the exhaust path 24, and the remaining part is recirculated to the blower fan 27 for circulation.

The drying device 21 can forcibly guide fresh air from the fresh air introduction passage 29 to the blowing fan 27 by the suction force of the blowing fan 27. Therefore, when the circulating air volume adjusting damper 33 is fully closed, all of the hot air blown out from each nozzle 3 can be exhausted from the exhaust path 24 to the outside, and fresh air having the same amount as the exhaust air volume is supplied from the fresh air introduction path 29. The air can be forcibly guided to the suction port 27a of the blower fan 27 through the space C (a part of the recirculation path 25), and so-called full exhaust can be performed. Further, when opening the circulating air volume adjusting damper 33, a mixed air of a part of the hot air which is returned from each of the nozzles 3 and then recirculated and fresh air is forced to the suction port 27 a of the blower fan 27 in accordance with the opening degree. And the same amount of exhaust air as fresh air
4 to the outside.

As shown in FIGS. 1 and 4, the difference between the other drying device 41 and the above-described one drying device 21 is that the partitioning wall 38 of the one drying device 21 is not provided, and That is, the side is formed by the duct 42. The duct 42 has one end joined to the suction port 27a of the blower fan 27, the other end joined to the circulating-air-volume adjusting damper 33, and the end 29a of the fresh air introduction passage 29 joined to a midpoint B thereof. . The configuration of the other drying device 41 other than this difference is substantially the same as that of the above-described one drying device 21.

[0022]

As described above in detail, the drying apparatus according to the present invention has the following excellent effects.

According to the first aspect of the present invention, since the fresh air is forcibly guided from the fresh air introduction path to the blow fan by the suction force of the blow fan, the blow fan for introducing fresh air can be omitted. In addition, manufacturing costs and operating costs can be reduced.

According to the second aspect of the present invention, since there is no need to form a return path between the partition wall and the suction port of the blower fan by a duct, the structure is simplified and the manufacturing cost can be reduced.

[Brief description of the drawings]

FIG. 1 shows an embodiment of a drying device according to the present invention, and is a schematic diagram in which two types of drying devices are joined in series.

FIG. 2 is a plan view in which one of the drying devices in the embodiment is partially cut away and cross-sectioned.

FIG. 3 is a front view of one of the drying apparatuses according to the embodiment, which is viewed from the front in the web advancing direction and partially cut away.

FIG. 4 is a plan view in which the other drying device in the embodiment is partially cut away and sectioned.

FIG. 5 is a schematic diagram of a conventional drying device.

FIG. 6 is an overall perspective view showing a drying chamber of a conventional drying apparatus with a casing omitted.

[Explanation of symbols]

 3 ... Nozzle 21 (41) ... Drying device 22 ... Drying room 24 ... Exhaust passage 25 ... Recirculation passage 26 ... Ventilation passage 27 ... Ventilation fan 29 ... Fresh air introduction passage 33 ... Circulating air volume adjustment damper A (B) ... Joint 37: Fan installation room 38: Partition wall 38a: Suction port C: Space

Claims (2)

[Claims] 1. A nozzle disposed in a drying chamber, an exhaust path extending from the drying chamber to the outside, a return path leading to the drying chamber, an air path leading to the nozzle, and a path between the return path and the air path. In a drying apparatus provided with a blower fan disposed in the air and a fresh air introduction path provided with a filter and joined to the return path, the return path is located upstream of a junction with the fresh air introduction path not provided with a pushing fan. A drying device, characterized in that a circulating air volume damper is disposed on the side. 2. The fan fan is disposed in a fan installation chamber formed integrally with the drying chamber, a partition wall is provided between the drying chamber and the fan installation chamber, and a suction port is provided in the partition wall. 2. The drying apparatus according to claim 1, further comprising a damper for adjusting the amount of circulating air, wherein the fresh air introduction path is opened in a space between the partition wall and a suction port of the blower fan.