JPS59187627A - Low-temperature stretch-breaking apparatus - Google Patents

Abstract

PURPOSE:To provide the titled apparatus capable of carrying out the stretch- breaking of a yarn maintaining the fiber at a low temperature, and removing the heat generated by the stretch-breaking process, by connecting a cooling chamber at the former stage of a stretch-breaking machine, and placing a low-temperature stretch-breaking tank furnished with a cooling means between a clamping roller and a stretch-breaking roller. CONSTITUTION:The cooling tank A is attached to the former stage of the stretch-breaking machine 3, the inlet port and the delivery port of the fiber bundle are closed with a pair of feed rollers 4,4 and a pair of clamping rollers 1, 1, respectively, and a cold fluid is circulated. A low-temperature stretch- breaking tank B is placed between the clamping rollers 1,1 and the stretch- breaking rollers 2,2, the upper and the lower surfaces of the fiber bundle running between the rollers 1,1 and the rollers 2,2 are cooled with the cooling plates 8,8, and the tank B is sealed with the rollers 1,1 and the rollers 2,2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for carrying out freezing, which is one of the methods for producing a discontinuous fiber bundle from a continuous fiber bundle. The purpose of this is to continuously cool the continuous fiber bundle, maintain the fiber temperature at a low temperature during tension cutting, and remove the tension cutting heat generated during tension cutting to suppress the rise in fiber temperature and take advantage of the benefits of frozen tension cutting. The objective is to provide a low-temperature tension cutting device that provides reliable results.

The freezing tension cutting method is patent application No. 56-157420.56-158.
As shown in the specification of No. 195, in tow spinning, when producing a bundle of discontinuous fibers from a bundle of continuous fibers, the fibers are cut by tension at a low temperature. The physical properties of the single fibers are maintained with almost no deterioration compared to the physical properties of the continuous fiber bundle before tension cutting. Figure 1 shows 3d acrylic synthetic fiber (trade name: Riki 7 Milon ■).

A tension-elongation diagram at each temperature for a bundle of 20 pieces is shown. 1st
As is clear from the figure, the amount of plastic deformation in tension cutting at low temperatures is extremely small, and cutting can be performed near the elastic region, so the strength and elongation of the single fiber after cutting is maintained, and the residual strain is small. ('C) It is possible to obtain a bundle of discontinuous fibers having a group of single fibers with extremely low single fiber shrinkage rate due to boiling. If each of the single fibers constituting the supplied continuous fiber bundle is crimped, it is possible to obtain a discontinuous fiber bundle in which the crimps are maintained even after stretch cutting. Therefore, compared to the conventional spinning process, the process can be significantly shortened and quality can be improved. Furthermore, as the fiber f 3 ) temperature during tension cutting is lowered, the cutting transitions from ductile fracture to brittle fracture, and the cut surface of the single fiber becomes a tapered tip. As mentioned above, the frozen tension cutting method is a very effective and characteristic tension cutting method.

However, fibers generally generate heat when they are stretched and cut.

This is because when work is applied to a fiber, when it deforms elastically, this work is stored as potential energy, but when it deforms further and begins to deform plastically, this work is converted into thermal energy and dissipated. . In FIG. 1, the area of plastic deformation at 20°C is α, α', b'·b, and this work determines the amount of heat generated. When this area line cutting temperature decreases, it increases by -q and then decreases, and -1
When the temperature is 00°C, the cutting occurs almost within the elastic region, and the amount of heat generated is significantly reduced. FIG. 2 shows the relationship between this plastic deformation region and cutting temperature. Here, the fiber bundle shown in Figure 1 is a low elongation type fiber with a trade name of 7 milon, but it is cut at a temperature below the clenching temperature, and is cut within or near the elastic region. In the region (4), the heat generated by tension cutting almost disappears. On the contrary,
The tension-cutting heat raises the temperature of the fiber, causing even greater tension-cutting heat to be generated, and the fiber temperature rises rapidly. Therefore, in order to bring out the original advantages of freezing tension cutting without losing its original advantages, it is necessary to quickly remove tension cutting heat when it occurs.

This invention was made in view of the above circumstances, and its gist is that a cooling tank for cooling the fiber bundle is connected to the front stage of a tension cutting machine that cuts the fiber bundle between a gripping roller and a tension cutting roller, The low-temperature tension cutting device is characterized in that a low-temperature tension cutting tank equipped with a cooling means is provided between the gripping roller and the tension cutting roller.

This device is equipped with a cooling tank in front of the tension cutter, so it can be used continuously. The fiber bundle is deep-cooled in advance in a cooling tank, and then continuously fed into a tension cutter and cut.

t&, when tension cutting heat is generated due to tension cutting, the heat is absorbed in the low temperature tension cutting tank and the temperature of the fiber bundle is prevented from rising. Therefore, according to this device, the advantages of freezing and tension cutting can be properly realized without being impaired. That is, since stretch cutting is performed near the elastic region where the amount of plastic deformation is extremely small, the physical properties of the single fiber before stretch cutting are hardly impaired. For example, crimp is maintained and single fiber shrinkage is kept at an extremely low level. Further, the cut end can be made into a tapered point by brittle fracture.

Hereinafter, an explanation will be given of the apparatus of the embodiment using a gold-plated metal.

In FIG. 3, a cooling tank A for cooling the fiber bundle is installed upstream of the tension cutter 3 that cuts the fiber bundle between a pair of gripping row tools 1.1 and a pair of tension cutters p-2-2, 2. are installed continuously. In the cooling tank A, an inlet for the fiber bundle is closed by a pair of feed rollers 4.4, and an outlet is closed by a pair of gripping rollers 1.4.
1, the outer periphery is in the shape of a rectangular parallelepiped covered with a heat insulating material 5, and there is a tunnel-shaped fiber bundle passage 6 bent in a zigzag manner between the inlet and the outlet, and the fiber bundle passage 6 in the upper part thereof is A low temperature fluid circulation path 7 communicating with the passage 6 is provided near the inlet and outlet.

This device also includes a gripping roller 1.1 and a tension cutting roller 2.
．． A low-temperature tension tank B is provided between the two. This ffBJ:
l: It is covered with a heat insulating material 5, has a rectangular parallelepiped shape, and the inlet and outlet are respectively closed by a pair of gripping rollers and tension cutting rollers 2, 2. The fiber bundle is cut between rollers 1.1 and 2.2 with all the drawing forces and/or shearing forces. In this ritual, in order to effectively cool the fiber bundle during cutting, two cooling plates 8. It is arranged. In FIG. 3, C is a refrigerator unit that supplies the cold energy required for freezing, and D is a coiler.

FIG. 4 is a detailed view of the cooling tank. Inside the circulation path 7, there is a cooler 9 connected to the refrigerator, a heater 10 for boxing inside the cooling tank, and an air supply 7 amp 11. The highly cooled low-temperature air enters the passage 6 on the outlet side from the circulation path 7, flows through the passage 6, and returns to the circulation path 7 from the passage 6 on the inlet side for multiple circulation.

Inside the cooling tank A, as shown in Fig. 5 (α) and (b),
A lower tunnel forming frame AI with a recess 12 and an upper tunnel forming frame A2 with a protrusion 13 are arranged so that the protrusion 13 is located within the recess 12, thereby forming a tunnel-shaped fiber bundle passage bent in a zigzag manner. 6 is formed.

Furthermore, a set of two 7-frame frames 14° 14 as shown in FIGS. 6(α) and (6) are arranged facing each other on both sides of the passage 6.
A rotating roller 16 with ribs 15 is mounted at the upper and lower bent portions of the V-shaped passage 6, with both ends supported by frames 14.

FIG. 7 shows nine rotating rollers 16 supported by seven frames 14.
7 shows the bearing part of 7 and 17. 7 rams 1 set of 2 pieces
4, 14 and 7 shafts 17 constitute the structural 7 frames of cooling tank A. A heater 19 is attached to the end of the shaft 17 to prevent grease from freezing inside a rotating roller 16μ bearing box 18 that guides the fiber bundle as it bends. The temperature inside the cooling tank is the bearing's operating limit temperature -4
The heater 19i is set to work when the temperature becomes 0 (T) or less. -! In addition, by using a material with low temperature resistance and self-lubricating properties, such as a 7-layer resin or an ultra-high molecular weight polyethylene resin, for the rotating roller 16, the weight can be reduced and it can be used even at extremely low temperatures. can withstand.

As shown in FIG. 8, the feeding force roller 4.4 attached to the feeding port applies a load to the shaft of the spring 2o roller roller 4, nips the M thin bundle between the rollers 4, 4, and lowers the lower roller 4. The fiber bundle is fed into the cooling tank A by driving the shaft. Gripping roller provided at the drawer port 1. The fiber bundle is pulled out by a load and drive from outside the tank, and sent into the low-temperature tension cutting tank B. The atmosphere cooled in this vA% circulation passage 9 is transferred to the air supply passage 6 11.
The inside flows from the outlet side to the inlet side. The fiber bundle transported through the passage 6 comes into countercurrent contact with the low temperature atmosphere and is rapidly deep cooled.

Generally, when fibers are cooled, the volume shrinks like other substances, and the shrinkage rate in the direction of the fibers is significant. Therefore, when the fiber is cooled from room temperature in a state where the initial tension is close to zero, tension is generated due to this contraction phenomenon, and the magnitude of the tension increases as the temperature decreases. When the fiber is further cooled to an extremely low temperature, the elongation at break decreases significantly and some of the continuous fibers in the bundle are cut. 9. Fiber is also used as a heat insulator, #l! The specific heat of the fiber itself is not small and its thermal conductivity is also small, so it is difficult to cool it down.
If the fibers are assembled into a bundle and each single fiber is in contact with each other, the cooling efficiency will be significantly reduced. Therefore, in order to efficiently cool the fiber bundle without causing single fiber breakage, it is necessary to always cool the fiber bundle in a state where the tension is relaxed.

In the cooling tank of the tension cutting device, the linear speed ratio between the feeding of the fiber bundle by the feeding roller 4.4 and the pulling out of the gripping roller 1.1 is variable. Therefore, the linear speed of the feed roller is set higher than that of the gripping roller to overfeed the entire fiber bundle. The fiber bundle that is fed into the tank is nipped by a multi-feed roller, and the room-temperature air it contains is compressed and removed, and the fiber bundle is released from the load of the feed port. O/(-) expands in the tank due to the feed action, and the cold air in the tank enters the inside of the fiber bundle, allowing it to be cooled uniformly and efficiently.Furthermore, it absorbs the shrinkage of the fiber bundle due to cooling in the cooling @A, and This prevents the crimp from stretching out between the rollers, and also makes it possible to relieve the tension that occurs between the rollers.If the single fiber has crimp, it contains a lot of air between the fibers and cools. Although it is difficult to do so, overfeeding allows for good cooling.

These two pairs of feeding rollers and gripping rollers of the cooling tank are rubbed against the wall surface of the cooling tank to form a flexible roll to prevent the cold air inside the cooling tank from coming into contact with the outside air. Additionally, when the temperature of the tank decreases due to the cooler 9, the internal pressure of the tank becomes negative with respect to the outside pressure, making it easier for moisture-containing outside air to enter through the inlet, outlet, etc., resulting in dew condensation. This causes problems in the simultaneous rotation of each roller. A supply port 21f for low-temperature vaporized gas such as liquid nitrogen is provided at an arbitrary position in the cooling tank A, and a very small amount of low-temperature vaporized gas is supplied into the tank so that the pressure inside the tank becomes extra pressure with respect to the outside pressure. , prevent outside air from entering. Furthermore, in addition to the feed roller 4°4, other means such as multiple slits with small gaps through which fiber bundles can enter and exit may be added to the inlet to suppress outside air from flowing into the tank. . Also 1 hour cooling NA
In order to further increase the cooling efficiency of the

As shown in (6), a large number of fin-shaped protrusions 22i made of a highly thermally conductive material such as copper may be arranged on the wall surface of the tunnel-like passage 6 parallel to the direction of transport of the fiber bundle.

At this time, the fiber bundle transferred in the passage 6 cleanly moves to the protrusion 22, and the internal fibers also frequently come into contact with the protrusion 22, which has become low temperature, and are spread in the width direction and thickness direction. It is evenly and efficiently cooled. In addition, the cooler 9 is not provided in the cooling tank A, and the pline sufficiently cooled in the refrigerator C is brought into contact with the wall surface of the tunnel-shaped passage 6 in the cooling tank through a pipe or the like so as to be circulated for convenient heat exchange. In particular, the fiber bundle can also be deep cooled.

The temperature inside the cooling tank is detected by installing a detection end such as a platinum resistor or thermocouple in any position such as behind the cooler 9 or inside the supply port in the circulation path 7#7'3, and the temperature is detected when the refrigerator is operated. to automatically adjust the temperature inside the cooling tank.

Figure 10 is a detailed diagram of the low-temperature tank B. On the F side of the cooling plate in the tank, there is a cooler and an air supply fan that circulate the refrigerant inside the tank, cooling and circulating the atmosphere inside the tank. . Then, the linear speed of the tension cutting rollers 2, 2 is made higher than the linear speed of the gripping roller 1.10, and an appropriate load is applied using hydraulic pressure, etc., and the fiber bundle is chaptered between the two pairs of rollers to form a discontinuous fiber bundle and spun. put out The temperature inside the tank is detected by a temperature detection end such as a platinum resistor or thermocouple installed at an arbitrary position, such as near the gripping roller 1.1 and the passage rollers 2, 2, or behind the cooler prisoner.
Automatically control.

In general, frying occurs when tow t'', but if the metal area is sealed, this layer will accumulate and interfere with continuous operation, or it will float and enter the sliver, reducing the quality. In tank B, for convenience of removal, a filter 25 is installed in the circulation passageway at the bottom of the tank to collect flies.
To prevent the single fibers from wrapping around the rollers,
A bluff 26 is provided. In order to prevent the atmosphere inside the container, which has become low in temperature, from contacting the outside air, two pairs of rollers are installed on the side surfaces and flI.
The rollers 27 are placed in circular grooves in four places on the roller surface and the floor space to perform flexible rolling. In addition, since the nip is applied between the two pairs of upper and lower rollers with an appropriate load,
Prevent contact between the tank atmosphere and outside air. Here, the gripping roller 1.1 and the passage roller 2.2 are made of a combination of rubber with excellent low-temperature resistance and mechanical properties, and a 7-layer resin or an ultra-high molecular weight polyethylene resin, and are coated with these. But it's okay. Furthermore, the roller n also uses these trees with excellent self-lubricating properties.

Cooling plates 8°8 are provided above and below the fiber bundle during tension cutting, so that metal plates with excellent thermal conductivity such as copper or aluminum do not obstruct the progress of the fiber bundle.

It has a contact surface with a smooth finish and rounded ends. The cooling plate 8 is fixed to the lower part of the tank with a bar or the like, and the cooling plate 8 is placed on the fiber bundle in the middle of tension cutting so that it can move only in the vertical direction, such as by providing holes through which the cooling plate 8 passes. Further, a spring load is applied to the spring so as to actively contact the fiber bundle to such an extent that it does not interfere with the running of the fiber bundle. The heat generated by tension cutting can be detected by a temperature detecting end provided at an arbitrary position on the cooling plate 8.8, and the tank internal temperature 't-a may be adjusted based on this temperature. When tension-cutting heat occurs, the heated cooling plates 8, 8 are cooled by the low-temperature atmosphere in the tank, and the fiber bundles that are in the middle of tension-cutting are heated by contacting a metal with excellent heat transfer. It can quickly remove heat from the body. As shown in FIG. 11, a number of fins 28 can be attached to the surface of the cooling plate 8.8 to improve heat exchange. Also, the cooling plate 8.
8, the cooler 23 is shaped so that it does not obstruct the progress of the fiber bundle, and is brought into contact with the fiber bundle, and the pipe 29 is cooled sufficiently in the refrigerator C, as shown in FIG. 12. It can also be cooled by being brought into contact with the cooling plates 8, 8 for convenient heat exchange and circulating within the refrigerator C.

Fiber bundles that can be cut with this tension cutting device include fiber bundles such as filaments, large filaments, and tows with a total denier of 30 to 2 million yen, consisting of single fibers with a denier of 0.1 to 1oO@]. Chemical fibers such as polyacrylic and polyester are mainly used. It is best to use a low-temperature gas such as liquid nitrogen or air for cooling, but the cooling tank is further filled with this low-temperature gas, and the fibers are circulated by flowing through the passage in the opposite direction to the traveling direction of the fiber bundle. Increases the cooling efficiency of the bundle and the sound. In addition, since the thermal conductivity of gases such as nitrogen gas and air to fibers is low,
It is possible to bring the fiber bundle into contact with a metal with excellent thermal conductivity such as copper or brass, or to keep it in constant contact with metal protrusions to spread the fibers and cool them uniformly and efficiently to the inside.

The present invention is as described above, and this device realizes the original merits of frozen stretch cutting, making it possible to streamline the production process and produce high-quality discontinuous fiber bundles.

Furthermore, the device of the embodiment provides the following effects. In the cooling tank.

■ The feed roller and take-off roller prevent the cold air inside the cooling tank from contacting the outside air, and if the bundle of fibers to be cooled has crimps, compress the outside air and cold air contained between each single fiber. and improve cooling efficiency.

■ By differentiating the linear speed of the feed roller and the draw-throat roller and overfeeding, it is possible to prevent single fibers from being cut or crimped from stretching out between the fiber grips in the cooling tank, and to reduce the contact area with cold air. The top increases cooling efficiency.

■ Multiple rotating bars with flanges at both ends that prevent condensation prevent single fibers from breaking and prevent single fibers from wrapping around.

■ By circulating the cold air in the cooling tank, the cold air that comes into contact with the bundle of fibers to be cooled can be made to flow, allowing uniform and efficient cooling.

■ The bundle of fibers to be cooled can be efficiently cooled by bringing them into surface contact with a metal with excellent thermal conductivity (16) in the cooling tank.

In the low-temperature tension-cutting tank B, (1) continuous fiber bundles can be tension-cut in a low-temperature atmosphere, and the temperature of the fibers, which have been heated by tension-cutting heat, can be quickly lowered.

[Brief explanation of the drawing]

Figure 1 shows acrylic synthetic fiber (product name: force 7milon)
3d, tension-elongation diagram at each temperature for 20 bundles, 2nd
Figure 3 is a correlation diagram between the plastic deformation region and cutting temperature leading to two types of tensile cutting of μ strain millon ■, Figure 3 is an overall schematic diagram of the tension cutting device of the example, and Figure 4 is a longitudinal section of the cooling tank. Figure, Figure 5 (
cL). (6) is a side view of the lower and upper tunnel forming frames;
Figures (α) and (6) are a side view of the 7-frame and a front view of the 7-frame with the rotating roller attached, Figure 7 is a sectional view of the bearing of the rotating roller, and Figure 8 is a view of the inlet of the cooling tank. Front view partially shown in section, FIG. 9 (α). 11. (b) is a side view and a plan view of a passageway with fin-shaped protrusions attached, FIG.
Figure 12 (α) is a plan view and a side view of a cooling plate with a fin-like object and a pline circulation pipe attached. !... Gripping roller 2... Tension cutting roller 3...Tension cutter 4...Feed roller 5...Insulation material 6...
Passage 7... Circulation path 8... Cooling plate 9... Cooler lO... Heater 11... Air supply fan 12... ...Concave portion 13...Convex portion 14...Frame 15
...Kuha 16...Rotating roller 17.
...Shaft 18...Bearing box 19...
・Heater 20... Spring 21...
・Low temperature vaporized gas supply port 22... protrusion
Container: Cooler: Air supply: 7 amps: Filter: 26: Plan: 27
...Roller edict ...Fin-like object 29
...Pipe A...Cooling tank B.
・・・・・・Low temperature tank C・・・・Freezer unit
D...Coiler person 1+A2...Lower and upper tunnel forming frame (6) q. Figure 6 Figure 5 (CI) (b) Figure 7 Figure 8 Figure 9 (a) ) (b) (b) 2B

Claims (5)

[Claims] (1) A cooling tank for completely cooling the fiber bundle is installed in front of the tension cutting machine that cuts the fiber bundle between the gripping roller and the tension cutting roller, and between the gripping roller and the tension cutting roller, A low-temperature tension cutting device characterized in that a cooling means is provided with a low-temperature tension cutting tank. (2) The low-temperature tension cutting device according to claim 1, wherein the cooling tank has a fiber bundle inlet and a fiber bundle outlet each closed by a pair of feed rollers and a pair of gripping rollers. (3) The low-temperature tension-cutting tank according to claim 1, wherein the fiber bundle inlet and the fiber bundle outlet are respectively closed by a pair of gripping rollers and a tension-cutting roller. Device. (4) The cooling tank has a zigzag-shaped tunnel-shaped fiber bundle transfer path between the inlet and the outlet, and means for causing the cooled tank atmosphere to flow along the path;
Claim 1, characterized by comprising means for varying the linear velocity ratio of the feed roller and the gripping roller.
The low-temperature tension cutting device described in section. (5) The low-temperature stretch cutting tank is equipped with a cooling body that comes into contact with the fiber bundle running between the gripping roller and the tension cut roller and cools the fiber bundle. The low-temperature tension cutting device described.