JP2003019747A - Tenter oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tenter oven removing lubricant or an oligomer contained in hot air after heating a film to the outside from a main body to prevent the same from condensing to drip form the ceiling of the main body or to adhere to and accumulate on the inner wall of the main body. SOLUTION: A plurality of plenum ducts having gaps for blowing off hot air heated by a heater are arranged in the main body of the heating section of the tenter oven and a suction port for sucking hot air used for heating the film is provided to the main body of the heating section and a suction duct for allowing hot air after the heating of the film to flow to the heater is connected to the suction port. The branch duct branched from the suction duct to again meet with the suction duct is connected to the suction duct and a cooling heat exchanger for removing a volatile component in hot air is inserted in the branch pipe and a branch flow rate adjusting device for adjusting the flow rate of hot air branched from the suction duct to the branch duct is provided to the suction duct and/or the branch duct.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for removing volatile components in the hot air of a tenter oven, in which hot air is circulated to a heater and a blower to stretch a sheet-like film in the transverse direction and / or the longitudinal direction. .

[0002]

2. Description of the Related Art In a tenter oven in which hot air is blown from above and below a continuously fed sheet-like film to heat and soften the film, and the film is stretched in the transverse direction or in the longitudinal and transverse directions, the hot air or warm air for heating the film is The structure in which the duct is sent from the main body of the tenter oven to the blower and the heater, the temperature is adjusted by the heater, and the flow is circulated again to the hot air blowing nozzle in the main body by the supply duct belongs to a known technique.

A conventional film transverse stretching apparatus disclosed in Japanese Patent Laid-Open No. 9-150455 discloses a method for stretching a stretched film by applying hot air heated to a predetermined temperature by a radiator placed on the lateral side of the film running portion of the apparatus body. Sprayed up and down, when stretching while repeating the operation of heating the sprayed hot air again with a radiator and spraying the stretched film, the hot air sprayed on the upper side of the stretched film is guided to the lower part of the radiator with a baffle plate and heated, The baffle plate guides the hot air sprayed to the lower side of the stretched film to the upper part of the radiator to heat and stretch it, thereby reducing the variation in the temperature above and below the stretched film and improving the accuracy of the thickness of the stretched film. To do.

The conventional plastic heating device disclosed in Japanese Patent Laid-Open No. 5-253434 branches a part of the circulating hot air and cools the branched hot air to make gaseous impurities in the hot air into droplets and It is a method and device for removing impurities in a circulating heating air that recovers and removes dripping impurities, and returns the hot air from which the impurities have been separated and removed to a regular circulation path. The purpose is to remove well.

[0005]

As shown in FIG. 7 which is a sectional view of a conventional tenter oven body, a hot air nozzle and a plenum for supplying hot air to the hot air nozzle are provided inside a heating section 31 of the tenter oven body. Duct 3,
4. Since the film clip for feeding the film 17 while stretching it in the lateral direction and the rail for running the same are installed, the cross-sectional area and volume are large, and the flow of hot air in the conventional oven body is D and E. As shown in, there are those that are immediately sucked into the suction duct 11 and those that are sucked after being stagnant for a while, and the temperature of stagnant air is lowered, and the lubricating oil and oligomer that have been vaporized are condensed into droplets, There is a problem in that the film adheres to and deposits on the wall or ceiling of the tenter oven and drops on the film to stain the wall of the oven, or deteriorates during stagnation and mixes with the circulating hot air to contaminate the surface of the film.

Even in the film stretching apparatus in which the radiator of the conventional example is placed on the lateral side of the film running section, the hot air on the return side is once released into the large room of the apparatus main body and then guided to the radiator by the baffle plate. Because
There is a part where the flow of hot air is stagnant, and there are variations in temperature,
It is inevitable that the condensed lubricating oil or oligomer adheres to and deposits on the inner wall of the apparatus.

The present invention provides a tenter oven in which the lubricating oil or oligomer in the hot air after heating the film is removed to the outside of the main body, and these are prevented from condensing and dripping from the ceiling of the main body or adhering and depositing on the inner wall. The purpose is to provide.

[0008]

In order to solve the above problems, the present invention provides (1) a sheet-like film that is continuously fed by blowing hot air to heat and soften the film and stretch it in the transverse direction and / or the longitudinal direction. In a tenter oven including a heating section, a plurality of plenum ducts having a gap for blowing hot air heated by a heater are arranged inside the main body of the heating section, and the film is heated by being blown out from the gaps of the plenum duct. The main body of the heating section is provided with a suction port for sucking the subsequent hot air, and a suction duct for circulating the hot air after heating the film to the heater is connected to the suction port, and the suction duct has the suction duct. Is connected to a branch duct that joins the suction duct again, and the branch duct is cooled to remove volatile components in the hot air. Interposed the use heat exchanger, wherein the intake duct and / or branch ducts, tenter oven, characterized in that a branch flow adjusting unit for adjusting the flow rate of the hot branch to branch duct from the suction duct.

(2) In the tenter oven described in (1) above, the branch flow rate adjusting device is a branch duct and a damper provided downstream of a portion of the suction duct where the branch duct branches. And tenta oven.

(3) In the tenter oven according to the above (1), the cooling heat exchanger is installed on or near the installation floor surface of the tenter oven, and the cooling heat exchanger is removed, replaced, or washed. The tenter oven is characterized by making it easy.

(4) In the tenter oven described in (1) above, the cooling heat exchanger comprises a plurality of hollow plates having elongated gaps through which the hot air passes, and the flow direction of the hot air flows between the plurality of hollow plates. 10. A tenter oven characterized in that it has a liquid reservoir at the bottom of the cooling heat exchanger body to cool the hot air by flowing cooling air in a direction perpendicular to the cooling air, and to collect condensed volatile component droplets.

(5) In the tenter oven according to the above (1), a porous straightening plate is provided in the heating section body for partitioning a space on the side where the plenum duct is arranged and a space on the suction port side. Each of the tenter ovens characterized by the above is used as a means for solving the problem.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The structure and operation of a heating section of a tenter oven according to an embodiment of the present invention will be described with reference to the drawings. 1 is a side sectional view showing a heating section of a tenter oven, FIG. 2 is a plan view showing an AA cross section of FIG. 1, FIG. 3 is a plan view showing a BB cross section of FIG. 1, and FIG. FIG. 5 is a side view showing a C-C cross section, FIG. 5 is a side view showing a porous part of the current plate of FIG. 1, and FIG. 6 is a perspective view showing a heat exchanger part of the volatile component removing device of FIG. 1.

In FIG. 1, reference numeral 2 designates a main body having excellent heat insulating properties in which a heat insulating material is sandwiched between double walls. The film 17 which is spread horizontally at the center of the main body 2 is clipped by the clip chains 18 which run horizontally on both edges and is fed while widening the film width.

The air in the main body is heated from the suction duct 11 and the confluent duct 12 through the heater 8 and is pressurized and sent by the blower 10. The ducts 5 and 6 are divided into a large number of plenum ducts 3 and 4, and the plenum ducts 3 and 4 are divided.
After being heated by blowing hot air pressurized from the narrow gap between the upper and lower surfaces of the film 17, the hot air is sucked into the suction ports 11a, 11b.
Into the suction duct 11 and then into the confluence duct 12. On the other hand, a part of the hot air passing through the recirculating suction duct 11 is branched to the branch duct 25 and guided downward, is cooled through the volatile component removing device 24 installed in the branch duct 25, and the volatile component is condensed. Then, after being removed, it merges with the original hot air that has been guided upward and branched, enters the merging duct 12, and is circulated to the heater 8 and the blower 10. Branch duct 25
The suction duct 11 and the branch duct 25 after the branch
Dampers 27 and 2 for adjusting the air passage area, respectively.
8 is installed to adjust the amount of air branched to the branch duct 25. Reference numeral 19 indicates a partition wall. The dampers 27 and 28 can adjust the amount of air branched to the branch duct 25 by only one of them.

As shown in the perspective view of FIG. 6, the volatile component removing device 24 is an air-cooling type heat exchanger having a long and narrow gap and a large number of hollow cooling plates 24a arranged side by side.
Airtightly attached to b and 24c, the circulating hot air is passed through the gap of the hollow cooling plate 24a, and the cooling air sent from the blower 26 is perpendicular to the flow direction H of the hot air (direction of arrow S in FIG. 6).
It is a heat exchanger configured to flow to and be cooled. Although not shown, the condensed droplets are collected in a liquid reservoir installed below. The branch duct 25 has a flange plate 24.
It can be attached and detached via b and 24c, and can be inspected and washed by detaching it from the branch duct 25 and volatile component removing device 24.

The temperature of the hot air passing through the plenum ducts 3 and 4 is detected by a temperature detection sensor (not shown), and the controller 8 (not shown) controls the heating amount of the heater 8 so as to reach the designated temperature for stretching the film 17. . Hot air is sucked in through the inlet 11a,
Before being sucked into the suction duct 11 from 11b, it passes through the straightening plates 15 and 16 (a large number of punch holes 15a and 16a are opened as shown in FIG. 5) provided in the main body. The opening ratio of the straightening vanes 15 and 16 is about 30%, and the hot air has a pressure difference before and after passing through the straightening vanes 15 and 16, and the suction holes 1 are evenly drawn from the punch holes 15a and 16a on the entire surface.
The suction ports 11a and 11 of the suction duct 11 flow into the chambers of the main body 2 without flowing a part of the hot air into the chambers of the main body 2.
b.

As shown in FIG. 7, if the main body 2 does not have the rectifying plates 15 and 16, the hot air is sucked into the suction duct 11.
The hot air stagnates in the corner portions indicated by D and E, because the shortest possible path is taken toward the suction ports 11a and 11b. Since such a portion where the hot air is stagnant is close to the wall of the main body 2, the temperature is lowered, and the oligomer gas evaporated from the film 17 and the petroleum-based gas vaporized from the lubricating oil in the running portion of the clip chain 18 are condensed. It adheres to the inner wall of the main body 2 and becomes dirty, or is altered during stagnation and mixed with the circulating hot air, and part of it passes through the filter 9 and the plenum duct 3,
4, the surface of the film 17 may be contaminated.

With the straightening vanes 15 and 16, the hot air is blown into the main body 2.
Since there is no stagnation in the room, the vaporized petroleum gas from the oligomer gas and the lubricating oil does not condense, and as described above, part of the hot air is branched to the branch duct 25, Since the volatile components are condensed and removed through the volatile component removing device 24 installed at 25, the concentration of gas such as oligomer generated during heating the film 17 can be suppressed.

Even when it is necessary to dry the wet film 17 by coating the surface of the film with a liquid, the constitution of the main body 2 in the heating section 1 of the tenter oven is the same as that of the drying section of the dryer. Can also be used as

In the case of this drying treatment, the hot air heated and dried by the heater 8 is sent by the blower 10 and passes through the main duct 7, the diversion ducts 5 and 6 and the film 17 from the narrow gaps of the many plenum ducts 3 and 4. The film 17 is dried by being blown to the upper and lower surfaces, and the moist warm air is collected in the suction duct 11, and most of the hot air passing through the suction duct 11 is branched to the branch duct 25 and guided downward, so that the branch duct 25 After being cooled by passing through the volatile component removing device 24 installed in the middle, the water vapor of the moist air is condensed and removed, and then it is guided upward and merges with the original warm air to join the merging duct 12
And enters the heater 8 and the blower 10.

The temperature of the hot air passing through the plenum ducts 3 and 4 is detected by a temperature detecting sensor (not shown), and the heating amount of the heater 8 is controlled by a controller (not shown) to pass the warm air passing through the plenum ducts 3 and 4. Make sure that the temperature of is the specified drying temperature.

Similar to the heating section 1 of the tenter oven, the hot air in the section is provided with a plurality of punch holes 15a, 16a provided in the main body 2 and straightening plates 15, 16 are formed.
And the warm air flows into the chamber on the suction port 11a, 11b side of the suction duct 11 at a uniform speed from the punch holes 15a, 16a of the entire area due to the pressure difference generated before and after passing the straightening plates 15, 16. The warm air can be made to flow into the suction duct 11 without stagnation in the second chamber.

If there are the straightening vanes 15 and 16, the warm air will flow into the main body 2.
Since there is no stagnation in the room, the water vapor contained in the warm air does not condense on the wall or ceiling inside the main body 2 and the inner wall of the main body 2 does not get wet or dirty.

[0025]

In the tenter oven of the present invention, a suction duct is connected to the suction port of the heating section body, and hot air is guided to a branch duct connected to the suction duct to evaporate from oligomer gas or lubricating oil in the hot air. It is possible to condense and remove volatile components such as petroleum-based gas that have been collected by a heat exchanger for cooling, and such volatile components may condense on the ceiling of the heating section body, which may drip and contaminate the surface of the film. It can be eliminated (Claim 1).

In the case where dampers are provided in the branch duct and the suction duct respectively, the operation in which the total amount of hot air from the heating section is introduced into the branch duct and the volatile components are condensed and removed by the cooling heat exchanger, and the cooling heat exchange is performed. In the operation of circulating the whole amount directly from the suction duct to the heater without passing through the device, or in the operation of adjusting the flow rate of the hot air branched to the branch duct to a predetermined ratio and condensing and removing the volatile components at the predetermined hot air flow rate. Both are possible, select them,
This enables efficient operation of the tenter oven in consideration of the concentration of volatile components in the heating section body (claim 2).

When the cooling heat exchanger is installed on or near the floor of the tenter oven, the cooling heat exchanger can be easily removed, replaced and washed (claim 3).

The cooling heat exchanger is air-cooled, and the condensed volatile component droplets are collected in a liquid reservoir arranged at the bottom of the cooling heat exchanger. Replacement and cleaning become easier (claim 4).

The heating section body of the tenter oven is provided with a porous rectifying plate for partitioning the space on the side of the plenum duct and the space on the side of the suction port. The hot air after the film is heated from the space on the side of the plenum duct by the porous partition plate. As a result of being rectified and transferred to the inlet side space, hot air does not settle in the corner of the plenum side space and stays in the space, and the film sent in the plenum side space volatilizes in the hot air stagnant in the space. The possibility of contamination with components can be eliminated (Claim 5).

By using the cooling heat exchanger for removing volatile components as a steam removing device for circulating hot air, the same main body structure can be used as a warm air dryer.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a heating section of a tenter oven according to a first embodiment of the present invention.

FIG. 2 is a plan view showing an AA cross section of FIG.

3 is a plan view showing a BB cross section of FIG. 1. FIG.

FIG. 4 is a side view showing a CC cross section of FIG. 1.

5 is a side view showing a part of a porous portion of the current plate of FIG.

6 is a perspective view showing a heat exchanger section of the volatile component removing apparatus of FIG. 1. FIG.

FIG. 7 is a side sectional view of a heating section of a conventional tenter oven.

[Explanation of symbols]

1 heating section 2 body 3, 4 Plenum duct 7 Main duct 8 heater 10 blower 11 Suction duct 12 confluence duct 15, 16 Current plate 17 films 24 Volatile component removal device 25 branch duct 27, 28 damper

Continued front page    F-term (reference) 4F210 AG01 QA02 QC01 QC05 QD32                       QD42 QG01 QL17

Claims (5)

[Claims] 1. A tenter oven including a heating section in which hot air is blown to a continuously fed sheet-like film to heat and soften the film, and the film is stretched in a transverse direction and / or a longitudinal direction, inside a main body of the heating section. Arranging a plurality of plenum ducts having a gap for blowing out hot air heated by a heater, and further comprising a suction port which is blown out from the gaps of the plenum duct and sucks in hot air after heating the film in the main body of the heating section, A suction duct that circulates the hot air after heating the film to the heater is connected to the suction port, and a branch duct that branches from the suction duct and joins the suction duct again is connected to the suction duct. The branch duct is provided with a cooling heat exchanger for removing volatile components in hot air, and the suction duct and / or The branch duct, tenter oven, characterized in that a branch flow adjusting unit for adjusting the flow rate of the hot branch to branch duct from the suction duct. 2. The tenter oven according to claim 1, wherein the branch flow rate adjusting device is a branch duct and a damper provided downstream of a portion of the suction duct where the branch duct is branched. oven. 3. The tenter oven according to claim 1, wherein the cooling heat exchanger is installed on or near an installation floor surface of the tenter oven, and the cooling heat exchanger is removed.
A tenter oven characterized by easy replacement and cleaning. 4. The tenter oven according to claim 1, wherein the cooling heat exchanger comprises a plurality of hollow plates having elongated gaps through which the hot air passes, and a direction perpendicular to the flow direction of the hot air between the plurality of hollow plates. A tenter oven characterized in that it has a liquid reservoir at the bottom of the cooling heat exchanger body for collecting cooling liquid by flowing cooling air to cool the hot air and collecting condensed volatile component droplets. 5. The tenter oven according to claim 1, wherein a perforated baffle plate for partitioning a space on the side where the plenum duct is arranged and a space on the suction port side is provided in the heating section main body. And tenta oven.