JPH062093U - Web dryer - Google Patents

Abstract

(57) [Summary] [Purpose] To improve the efficiency of energy utilization by reducing the drying efficiency of the web and the space of the drying device. [Structure] In a web drying device installed on a portion where a web is turned after a fluid is applied to the surface of the web 1 and is run through one or more drying devices, the web winding side of the drying device is , A non-contact bar 3 having at least one slit 4 or a plurality of holes 5 for drying air by holding air in a non-contact state is provided, and at least on the side opposite to the winding side of the web, A plurality of nozzles 7 having one or more slits 6 are arranged in the traveling direction, and one corner of the slit outlet is formed into an arc surface, and the air blown out from the nozzles by the Coanda effect is in the traveling direction of the web. It is designed to be parallel to.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a web drying device of a coating device.

[0002]

[Prior art]

 FIG. 4 shows a conventional web dryer. In FIG. 4, the web 1 to which the fluid is applied passes through the drying device 2, the traveling direction of the web is changed by the non-contact bar 3 ', and then the web 1 is again dried in the drying device 2'.

[0003]

[Problems to be solved by the device]

 In the conventional technique of FIG. 4, the coating liquid evaporates from the web 1 heated by the drying device 2, but the temperature of the web is changed at the portion where the direction of the web 1 is changed by the non-contact bar 3 ′. However, there is a problem that the drying ability is deteriorated and the drying ability is hindered. Further, hot air is blown out from the non-contact bar 3 ', but this hot air acts only on one side, and the hot air leaks out to both sides, resulting in a drawback that the energy efficiency is significantly reduced. This proposal is intended to solve the above conventional problems.

[0004]

[Means for Solving the Problems]

 For this reason, the present invention relates to a web drying device in which a fluid is applied to the surface of a web and then the web is run through one or more drying devices, and the web is to be turned. Is provided with a non-contact bar having at least one slit or a plurality of holes for blowing air to keep the web in a non-contact state for drying, and at least 1 is provided on the side opposite to the winding side of the web. A plurality of nozzles with three or more slits are arranged in the running direction, and one corner of the slit outlet is formed into an arc surface, and the air blown out from the nozzle is parallel to the running direction of the web due to the Coanda effect. The above is the method for solving the problems. Further, according to the present invention, the arc surface of the slit outlet corner portion at each end of each of the non-contact bar and the nozzle is formed at an inner corner portion of each slit outlet, and a hole leading to a vacuum chamber is provided between the nozzles. A pressure control plate is provided, and the exhaust duct provided in the vacuum chamber is connected to the air supply duct for supplying air to the non-contact bar and nozzle to circulate the air. Is a means for solving the problem.

[0005]

[Action]

 In the present invention, hot air is blown from the non-contact bar, and at the same time, a plurality of nozzles having at least one slit are arranged on the opposite surface of the web to perform both-side drying. When the hot air from the opposite side of the web hits the web vertically in the vertical direction, the dynamic pressure disturbs the floating of the web and makes the running unstable, so that the hot air moves in the direction of the web running due to the shape of the nozzle or the Coanda effect. Blow out horizontally. In addition, the nozzle installed on the opposite side of this web has end plates on both sides, and collects the hot air leaking to both sides through the gap between the web and the non-contact bar via vacuum pressure and circulates it. Therefore, according to the present invention, there is no decrease in the temperature of the web even in the portion where the direction of the web is changed, the drying of the web is promoted from both sides, and the leakage to both sides does not occur, and the energy efficiency is also reduced. Therefore, the drying efficiency is improved.

[0006]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIGS. 1 to 3 show an embodiment of the present invention. FIG. 1 shows a cross section of a portion where the direction of the web 1 changes. In the figure, the non-contact bar 3 on the winding side of the web 1 has slits 4 and 4 whose inner corners are arc surfaces at the entrance and exit of the web 1 and leaks from the entrance and exit of the web 1 by the Coanda effect. The air is suppressed. Further, between the slits 4 and 4, a large number of punch holes 5 for blowing air toward the surface of the web 1 at a substantially right angle are provided to create a pressure P necessary for floating the web 1. The pressure P is P = T / R, where R is the radius of gyration of the web and T is the tension. On the opposite side of the non-contact bar 3, an air chamber 14 having a plurality of nozzles 7 having slits 6 directed to the web 1 side is arranged so that both sides of the web 1 are dried. Since one corner of the exit of the slit 6 is formed into an arc surface, the air blown out from the slit 6 flows in parallel with the web 1 as indicated by the arrow by the Coanda effect. The arcuate surfaces at the corners of the slit outlets at the both ends of the non-contact bar 3 and the nozzle 7 are formed inward. 2 is a development view taken in the direction of arrow A in FIG. 1, and FIG. 3 is a sectional view taken along line BB of FIG. 2 and 3, 8 is an air supply duct, 9 is a nozzle air supply hole, 10 is a pressure control plate provided between the nozzles 7 and 7, and the plate 10 is formed by an end plate 11 and an exhaust duct. A hole 15 through which air is sucked is provided toward a vacuum chamber 12 communicating with 13. The air supplied from the duct 8 into the air chamber 12 passes through the nozzle air supply hole 9 and is blown out from the slit 6 of the nozzle 7. Some of this air passes through the holes 15 of the pressure control plate 10 after hitting the web 1 or hits the end plates 11 at both ends, both of which are collected in the vacuum chamber 12 and supplied to the air through the duct 13. It is circulated to the duct 8.

[0007]

[Effect of device]

 As described in detail above, in the present invention, since the slits and holes for blowing air are provided on both sides of the web, the drying efficiency is considerably increased as compared with the conventional one, so that the length of the drying device is shortened and the space is saved. It becomes a drying device. In addition, the air blown out from the non-contact bar and the nozzle is collected and circulated through the vacuum chamber, so that the contribution ratio of the input energy to evaporative drying, that is, the energy utilization efficiency is greatly improved compared to the conventional one.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a web drying apparatus according to an embodiment of the present invention.

FIG. 2 is a development view taken along arrow A in FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a cross-sectional view of a conventional web drying device.

[Explanation of symbols]

 1 Web 3 Non-contact Bar 4 Slit 5 Punch Hole 6 Slit 7 Nozzle 8 Air Supply Duct 9 Nozzle Air Supply Hole 10 Pressure Control Plate 11 End Plate 12 Vacuum Chamber 13 Exhaust Duct 14 Air Chamber 15 Hole

Claims (2)

[Scope of utility model registration request] 1. A web drying apparatus, wherein a fluid is applied to the surface of a web and then the fluid is passed through a drying device or a plurality of drying devices to be installed in a portion where the web is to be turned, the web winding side of the drying device is: A non-contact bar having at least one slit or a plurality of holes for blowing air to hold the web in a non-contact state for drying is provided, and at least one or more of the webs is provided on the side opposite to the winding side. A plurality of nozzles with slits are arranged in the running direction, and one corner of the slit outlet is formed into an arc surface so that the air blown out from the nozzle is parallel to the running direction of the web due to the Coanda effect. A web drying device characterized by: 2. The web drying apparatus according to claim 1, wherein the arc surface of the slit outlet corner portion at each end of each of the non-contact bar and the nozzle is formed at an inner corner portion of each slit outlet, A pressure control plate provided with a hole leading to a vacuum chamber is provided between the nozzles, and an exhaust duct provided in the vacuum chamber is connected to the non-contact bar and a supply duct of air to be supplied to the nozzle to circulate air. A web drying device characterized by: