JP2574841Y2 - Hot air circulation type heat treatment furnace - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hot air circulation type heat treatment furnace suitable for heat treatment for stretching or relaxing monofilaments made of thermoplastic resin.

[0002]

2. Description of the Related Art Conventionally, as a hot air circulating heat treatment furnace for drawing or relaxing heat treatment of a monofilament, a hot air is blown from one side of an inner wall of the furnace, and a cross-flow type having a hot air suction port on an opposite wall, or a furnace. A parallel flow type or counter flow type having a hot air outlet at one end and a suction port at the other end is used.

[0003] When a monofilament is drawn using a cross-flow type hot air circulation type heat treatment furnace, hot air is blown from one direction with respect to the cross section direction of the monofilament.
In the case of a monofilament (0.6 mm or more), heat reception spots are generated on the surface and inside, and therefore, when the monofilament after drawing is immersed in warm water, there is a problem that the monofilament is twisted due to a difference in shrinkage ratio in the cross section.

To solve the above problems, a parallel flow type hot air circulation type heat treatment furnace for circulating hot air in the same direction as the monofilament running direction, or a hot air flow in a direction opposite to the monofilament running direction as shown in FIG. A counter-flow hot air circulation type heat treatment furnace for circulating water is adopted. According to these, although the twist of the monofilament is somewhat eliminated, the outlet of the hot air is formed so as to blow from one direction with respect to the running direction of the yarn, so that the monofilament is instantaneously near the outlet. There is a disadvantage that heat spots occur.

[0005]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems, and makes it possible to uniformly heat-treat an object to be processed. Particularly, when used for processing a monofilament, there is no heat reception spot, and the monofilament is immersed in warm water. An object of the present invention is to provide a hot-air circulation type heat treatment furnace which can eliminate twisting at the time and can obtain a monofilament having improved knot strength and transparency.

[0006]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, have arrived at a hot-air circulation type heat treatment furnace of the present invention.

That is, in the present invention, the inside of the furnace is monofilament.
Is a heat treatment furnace that heats
And the inner wall of the furnace downstream of the monofilament running direction (wall
Surface A) has a hot air outlet and a monofilament running direction.
Suction into the furnace inner wall (wall B) facing wall A on the upstream side
With an opening above the downstream side in the monofilament running direction
In a counter-flow hot-air circulation type heat treatment furnace that sends and circulates hot air to the flow side, the wall surface B provided with a suction port
In, projects at an angle of 20 to 70 degrees with respect to the wall (alpha),
Two or more chevron members that reflect hot air to the opposing wall A
The gist of the present invention is a hot air circulation type heat treatment furnace provided .

[0008] The following describes in more detail the present invention in the drawings
You. FIG. 1 is a side sectional view showing one embodiment of a hot air circulation type heat treatment furnace of the present invention, which is taken in a monofilament running direction.
A hot air outlet 3 having a flow straightening plate 8 is provided on the inner wall surface A of the upstream side of the furnace so as to face the wall surface A on the upstream side in the monofilament running direction.
A hot air suction port 4 having a flow straightening plate 9 is provided on the facing wall surface B.

The furnace inner wall surface B facing the hot air outlet 3 projects at an angle (α) of 20 to 70 degrees with respect to the wall surface ,
Two chevron members 1 that reflect hot air to the opposing wall A
The above is provided.

The angle (α) of the angled member 1 with respect to the wall surface is 20
Should be 70 degrees, it is less than 20 degrees, hot air volume decreases circulating reflected against the chevron member 1, Mo
The effect of uniformly heating the no-filament 2 is reduced. If the angle (α) exceeds 70 degrees, the hot air impinges on the chevron member 1 and becomes difficult to circulate after being reflected. In this case also, the effect of uniformly heating the monofilament 2 is reduced.

[0011] Yamagata member 1 in order to reflect the blowing direction opposite hot air must Ru provided two or more, three or more
Above provided Rukoto is preferable. In Yamagata member 1 is one, and significantly reduced the efficiency of reflecting the hot air, it is impossible to reduce the heat spots in the monofilament cross-section.

When the monofilament is drawn or relaxed using the hot air circulation type heat treatment furnace of the present invention, the air is warmed by the heater box 5 and the duct 7 is blown from the blower 6.
Through the hot air outlet 3. This hot air is reflected by the chevron 1, and after the monofilament 2 is uniformly heated from both sides by the reflected hot air, it is sucked through the hot air suction port 4. The monofilament 2 is uniformly heated from both sides by the reflected hot air reflected by the chevron member 1, so that heat spots are not generated on the surface and inside, and twisting during immersion in warm water can be eliminated.

As shown in the installation examples of FIGS. 2 and 3, the angled member 1 is connected to the furnace inner wall surface A on the side of the hot air outlet 3 and the hot air suction port.
When provided on both sides of the furnace inner wall B on the side of the inlet 4 , the hot air is easily reflected and circulated on the opposed chevron members 1 on both sides, and the effect of uniformly heating the monofilament 2 from both sides is further improved.

[0014]

Next, the present invention will be described in detail with reference to embodiments.

Examples 1 to 4 As shown in FIG. 1, an undrawn nylon monofilament of 32340d was stretched by variously changing the heat treatment temperature using a counter-flow hot air circulation type heat treatment furnace having three chevron members. Relaxation heat treatment was performed. At that time, the stretching ratio was 5.9 times, the relaxation rate was 20%, and the stretching and relaxation heat treatment were performed at the same temperature.
The knot strength, transparency and torsion during immersion in warm water of the obtained monofilament were evaluated, and the results are shown in Table 1. The evaluation method is as follows. Knot strength: measured according to JIS-L 1069-78. Transparency: By visual judgment. ○: good transparency, △: slightly opaque, ×: poor transparency Twist: Visually observe the twist after immersing the sample in a bundle of 10 to 20 1 meter long in hot water at 95 ° C for 20 minutes. Was determined. ○: no twist △: slightly twisted ×: twisted

Comparative Examples 1 to 4 The same operation as in the example was performed using a counter-flow hot air circulation type heat treatment furnace shown in FIG. Table 1 shows the evaluation results of the obtained monofilaments.

[0017]

[Table 1]

As is clear from Table 1, the monofilaments obtained in Examples 1 to 4 were free from twisting, and had good knot strength and transparency. On the other hand, the monofilaments obtained in Comparative Examples 1 to 4 in which no chevron members were provided had torsion, and knot strength and transparency were poor.

[0019]

As described above, if the hot air circulation type heat treatment furnace of the present invention is applied to the heat treatment of the monofilament, the monofilament is uniformly heated by the hot air, so that the heat receiving spot in the cross section becomes small, and the monofilament after drawing is obtained. Can be prevented from being twisted when immersed in warm water, and a monofilament having high knot strength and excellent transparency can be obtained. Furthermore, the hot air circulation type heat treatment furnace of the present invention can be drawn at a temperature about 20 to 30 ° C lower than the conventional hot air circulation type heat treatment furnace, so that monofilaments having the above characteristics can be obtained at low cost. it can.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing one embodiment of a hot air circulation type heat treatment furnace of the present invention.

FIG. 2 is an enlarged view of the vicinity of a hot air outlet showing an example of installation of the chevron member of the present invention.

FIG. 3 is an enlarged view of the vicinity of a hot air outlet showing another installation example of the chevron member of the present invention.

FIG. 4 is a side sectional view showing a conventional counter-flow hot air circulation type heat treatment furnace.

[Explanation of Signs] 1 Angle member 2 Monofilament 3 Hot air outlet 4 Hot air inlet 5 Heater box 6 Blower 7 Duct 8, 9 Rectifier plate α Angle to wall surface of angle member

Claims (2)

(57) [Scope of request for utility model registration] 1. A monofilament runs in a furnace without contact.
A heat treatment furnace for heat treatment
Hot air blows out to the furnace inner wall (wall A) on the downstream side in the running direction
Mouth, facing the wall A on the upstream side in the monofilament running direction
Has a suction port on the inner wall (wall B)
Hot air is blown to the upstream side from the downstream side in the lament running direction,
And circulating counter-current hot air circulation heat treatment furnace,
On the wall B provided with the suction port,
Projects in 70 ° angle (alpha), the wall surface A facing the hot air
A hot-air circulation type heat treatment furnace , wherein two or more angle members for reflection are provided . 2. On a wall A provided with a hot air outlet ,
Projecting 20 to 70 degree angle (alpha) relative to the wall surface, the hot air
Provide two or more angle members that reflect
The hot air circulation type heat treatment furnace according to claim 1 .