JPH08158141A - Device for spinning carbon fiber - Google Patents

Abstract

PURPOSE: To provide a new spinning device capable of making the thickness of a fiber tow uniform, stored at a spoke part arranged around top and bottom plates by nearly uniformly keeping a wind velocity of air around the top and bottom plates. CONSTITUTION: In this device for spinning carbon fiber consisting of a revolving nozzle 3 for centrifugal spinning, top and bottom two plates 9 and 10 concentrically arranged around the revolving nozzle vertically parallely, a periphery spoke 8 concentrically arranged around the top and bottom plates, a guiding path for taking out a fiber bundle and fixed on a part of the periphery spoke 8, a doughnut-type cylindrical chamber 15 arranged on one side of the top or bottom plate and an air blowing opening provided on the periphery of the outer wall of the chamber, an air inlet 12 is specifically installed on the cylindrical chamber 15 having many air reservoirs 14 of the same volume formed by many partitions directing from the side wall of the cylinder to the center of the circle and the air blowing opening specifically consists of many air nozzle holes 16 made on the side wall of the cylinder.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pitch-based carbon fiber centrifugal spinning apparatus.

[0002]

2. Description of the Related Art Centrifugal spinning is one of the methods for spinning carbon fibers. An example of this method is one spinning device used by the applicant. This device is shown in FIGS.
As shown in Fig. 3, isotropic pitch produced from centrifugal molecular distillation is used as a raw material, and is melted to a viscosity at which it can be spun in an extruder 1 while being quantitatively thin cylindrical rotary nozzle 3 through a constant flow gear pump. The rotary nozzle 3 supplied to the central portion of the nozzle and supplied with the pitch is carried to the outside of the nozzle by the centrifugal force generated by the rotation, and is discharged from the fiber discharge nozzle hole 4 to form fibers. However, since it is difficult to form fine fibers only by centrifugal force, slits 11 are formed at the upper and lower top plates 9 and 10 on the outer circumference of the nozzle.
Was provided, and air was ejected from the slit 11, and the fibers ejected from the fiber discharge nozzle holes 4 were placed on the air and the fibers were stretched to be conveyed to the continuous bundle collecting device while being used for spinning.

However, the variation in the fiber diameter was larger than expected, and when the cause was investigated, it was found that it was caused by the poor air flow velocity balance at the outer peripheral portions of the upper and lower top plates as shown in FIG. did.

As a result of further research on the above-mentioned poor balance of wind speed, conventionally, a slit plate was provided along the upper and lower ceiling plates, and a slit having a constant width was formed between the slit plates. Although air was being blown out, the slit gap is very narrow, so some unevenness on the top plate or slit plate caused unevenness in the slit gap, and there was only one air holding room for the air. It was found that the fact that it was being supplied via the air flow causes the lack of wind speed balance.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to maintain a substantially uniform air velocity balance in the outer peripheral portions of the upper and lower ceiling plates, so that the fiber tow thickened in the spokes provided in the outer peripheral portion of the ceiling plate can be thickened. The purpose of the present invention is to provide a new spinning device capable of uniforming the thickness.

[0006]

DISCLOSURE OF THE INVENTION The present invention provides a rotary nozzle member for centrifugal spinning, two top plates arranged concentrically around the centrifugal nozzle member in parallel with each other, and a concentric circle on the outer periphery of the top plate. Outer peripheral spokes, fiber bundle takeout guide passages provided in a part of the outer peripheral spokes, a donut-shaped cylindrical chamber provided on one side of the top plate, and an air blowing portion provided on the outer wall thereof. A carbon fiber spinning apparatus having: an air supply port provided in the center of the cylindrical chamber, and a large number of equal volume air traps formed by a large number of partition walls extending from the side wall of the cylinder toward the center of the circle. And a plurality of air nozzle holes provided on the side wall of the cylinder, wherein the air blowing portion is a carbon fiber spinning apparatus. The present invention will be specifically described with reference to the drawings. FIG. 4 shows a specific example of the device of the present invention.
In this embodiment, the melted carbon fiber is discharged from the fiber discharge nozzle hole 4 provided at the tip of the rotary nozzle 3 for centrifugal spinning. Two upper and lower top plates 9 and 10 are concentrically provided on the outer periphery of the rotary nozzle member for centrifugal spinning, and outer peripheral spokes 18 are concentrically provided on the outer periphery of the top plates 9 and 10. The spun yarn is interrupted here to form the fiber bundle and is directed to the fiber bundle extraction guide path. When the spun yarn reaches between the top plates 9 and 10, the upper top plate 9
A yarn spun by air ejected from a large number of air nozzle holes 16 provided on the outer periphery of a flat, flat cylindrical chamber 15 concentrically provided in a donut shape on the outer periphery of the rotary nozzle member. Are stretched to become fibers having a predetermined length and are blown toward the outer peripheral spokes 18. As shown in FIG. 5, the cylindrical chamber 15 is divided by a large number of partition walls 17 so as to evenly divide the donut (in this example, 1
6), multiple independent air reservoirs 2
0, 20 ... and the air reservoir chamber 20,
Air is supplied to 20 ... From the air reservoir 14 by the respective air supply pipes 19, 19. The amount of air supplied can be controlled by providing adjusting means in each of the air supply pipes 19, 19 ... Connected to the air reservoir chambers 20, 20. After a while from the start of operation, the air trap chamber 20,
In No. 20 ..., the temperature rises under the influence of the heat of the spinning portion, so the wind speed of the air ejected from each air nozzle hole 16, 16 ... Subtly changes, so make this even. It is preferable to control FIG. 6 shows a model diagram in which the wind speeds in all directions of the nozzle are measured by this. As is clear from FIG. 6, it can be seen that the wind speed is almost uniform in all directions. On the contrary, when the conventional apparatus of FIG. 1 is used, the wind speed in all directions of the slit 11 is as shown in FIG. 3, and the wind speed is considerably uneven.

[0007]

[Effect] According to the present invention, the donut-shaped cylindrical chamber is divided into a large number of air reservoir chambers by partition walls, and the air pressure in each air reservoir chamber is adjusted to be the same, so that the air is ejected from the air nozzle holes of each air reservoir chamber. By controlling the wind speed, the wind speed in all directions could be kept constant. As a result, the fiber diameter of the spun fiber was extremely uniform.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a conventional carbon fiber spinning device.

FIG. 2 is an overall cross-sectional view of a conventional carbon fiber spinning device.

FIG. 3 is a model diagram showing wind speeds in all directions of a slit portion of a conventional carbon fiber spinning device.

FIG. 4 is a partial cross-sectional view of a spinning portion of the carbon fiber spinning device of the present invention.

FIG. 5 is a horizontal sectional view of a donut-shaped cylindrical chamber of the present invention.

FIG. 6 is a model diagram showing wind speeds in all directions of air nozzle holes in the embodiment of the present invention.

[Explanation of symbols]

 1 Extruder 2 Rotating Shaft 3 Rotating Nozzle 4 Fiber Discharge Nozzle Hole 5 Upper Chimney 6 Lower Chimney 7 Heater 8 Heater 9 Upper Top Plate 10 Lower Top Plate 11 Air Ejection Slit 12 Air Supply Port 13 Slit Plate 14 Air Reservoir 15 Cylindrical Chamber 16 air nozzle hole 17 partition wall 18 outer peripheral spoke 19 air supply pipe

Claims (1)

[Claims] 1. A rotary nozzle member for centrifugal spinning, two top plates arranged concentrically on the periphery of the rotary nozzle member in parallel with each other, and outer peripheral spokes concentrically provided on the outer periphery of the top plate. A carbon fiber spinning device having a fiber bundle take-out guideway provided in a part of the outer peripheral spokes, a donut-shaped cylindrical chamber provided on one side of the top plate, and an air blowing portion provided on an outer wall thereof. The cylindrical chamber is provided with an air supply port at the center, and has a large number of equal-volume air retainers formed by a large number of partition walls from the side wall of the cylinder toward the center of the circle. The carbon fiber spinning device, wherein the blow-out portion is composed of a large number of air nozzle holes provided on the side wall of the cylinder.