JPS62113515A - Manufacturing device for pellet of composite material - Google Patents

Abstract

PURPOSE:To obtain the pellet of a composite material easily by a method wherein the composite material, mixed with high-tension fibers, is extruded through a dice having a slit-like opening and the thickness thereof is uniformed by a rolling roll, further, is notched by a rotary cutter into fore-and-rear direction and, thereafter, is cut finely by a pelletizer. CONSTITUTION:A plastic material and high-tension fibers H are supplied into the kneading screw device 3 of a screw type kneading machine 2 to knead and make a composite material while the composite material is extruded through a dice 4 provided at the fore end of the kneading screw device 3. The outlet opening 4a of the dice 4 is formed so as to be a slit type opening while a rolling roll 5, a rotary cutter 6 and a pelletizer 7 are provided sequentially before the dice 4. The plastic composite material, including the kneaded high- tension fibers H, is extruded easily through the slit-like outlet opening 4a of the dice 4 and is formed by the rolling roll 5 so as to have a constant thickness substantially. Further, the material is notched by the rotary cutter 6 into fore- and-rear direction and, subsequently, is cut by the pelletizer into left-and-right directions whereby cubic pellets may be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention is utilized in the technical field of composite materials, and particularly relates to an apparatus for producing pellets of composite materials containing high-tensile fibers.

(Prior Art) Composite materials in which high-tensile fibers are dispersed in organic or inorganic materials that can be plasticized by heating (hereinafter referred to as organic or inorganic plasticizers) have many uses and are becoming more popular in the near future. It is widely used. Since such a composite material is molded into a product by means such as injection molding, it is supplied in the form of pellets.

When kneading organic or inorganic plastic material using a heated kneading screw device of a screw mixer, this composite material pellet is produced by adding 1 fr of high-tensile fibers to the upstream side of the organic or inorganic plastic material.
After feeding and kneading with good fluidity, relatively small holes (
For example, it is manufactured by extruding it from a die with a large number of circular holes (about 3H in diameter).

However, the high-tensile strength fibers supplied during kneading are in the form of fragments obtained by cutting bundles of hundreds or thousands of fibers before being supplied, and conventionally, the high-tensile strength fibers supplied during kneading are in the form of fragments obtained by cutting bundles of hundreds or thousands of fibers.
The wings will be newly created. As described above, in the past, the high tensile strength fibers used to increase the strength of the composite material were on the short sides, and there was a problem that the reinforcing effect thereof was insufficient. Further, among high-tensile fibers, aramid fibers are difficult to cut as they are (cannot be cut continuously in an industrial manner), and cannot be shredded and fed to a kneading screw device.

If high-tensile fibers are fed as they are to the upstream side of the kneading screw device and kneaded, aramid fibers tend to be easily damaged, while high-tensile fibers such as carbon fibers tend to be damaged. If high-tensile fibers were supplied to the side, there was a problem that the fluidity was poor and the kneaded material could not be stably extruded from the narrow holes of the die. On the other hand, there is a coating method in which the long fibers are coated with a plastic material, but this method has the disadvantage that the two materials are not sufficiently mixed and the productivity is poor. In any case, composite pellets containing long high-tensile fibers have not been put to practical use.

(Problems to be Solved by the Invention) The present invention attempts to solve the above-mentioned problem that no manufacturing apparatus capable of manufacturing composite material pellets containing long high-tensile fibers has been proposed. be.

(Means for Solving the Problems) Means for solving the above problems in the present invention will be explained with reference to the drawings. Note that in FIG. 1, it should be understood that the left side is the front and the right side is the rear.

The pellet manufacturing apparatus 1 according to the present invention supplies a plastic material and high tensile strength fibers H to a kneading screw device 3 of a screw-type kneader 2 and kneads them into a composite material. The outlet opening 4a of the die 7-4 is made into a slit shape, and a rolling roll 5 is placed in front of the die 4.
, a rotary cutter 6 and a pelletizer 7 are installed in this order.

(Function) The effect of the above-mentioned means is that the plastic composite material containing the high-tensile long fibers H kneaded by the kneading screw device 3 has somewhat poor fluidity and can be easily passed through the slit-shaped outlet opening 4a of the die 4. being pushed out. This extruded band-shaped composite material is formed into a substantially constant thickness by a rolling row/L15, cut in the front-rear direction by a Sarani rotary cutter 6, and then cut in the left-right direction by a pelletizer to form rectangular parallelepiped pellets. is molded.

(Example) Examples of the present invention will be described in detail below.

Two kneading screw devices 3 are arranged in parallel on the left and right, and a uniaxial screw feeder 8 is provided at the rear upper part thereof, and is driven by a power means 8a. The front end 8b of the screw feeder 8 is communicated with the upper part of the rear end 3d of the kneading screw device 3. Furthermore, a hopper 9 is provided on the rear end portion 8C of the screw feeder 8 in communication with it. The plastic material charged into the hopper 9 falls onto the rear end 8c of the screw feeder 8, is transported forward by the screw feeder 8, and falls onto the rear end 3d of the kneading screw device 3. As the plastic material, a thermoplastic resin or a thermosetting resin is used as an organic material, and carbon or the like is used as an inorganic material.

A heater 3e is provided around the kneading screw device 3. Further, the screw 3C of the kneading screw device 3 is driven by a power means 3f. Furthermore, the difference between the cross-sectional area S3 in the cylinder 3g of the cross-contact screw device 3 and the cross-sectional area S4 of the screw 3c is calculated as the composite material passage cross-sectional area S
2, and on the other hand, the composite material passage cross-sectional area per 481 pieces of the opening part is S! When closed, the Sl is 10% or more (preferably 20% or more) of the S thread, but the lower limit is 3Qm! It is formed as. This is because, as will be described later, the supply point is relatively downstream of the kneading screw device 3 in order to prevent damage to the fibers when the high-tensile long fibers H are fed into the kneading screw device 3 and kneaded. This is to prevent the fluidity when exiting the die 4 from being poor and the extrusion to be unstable if the opening hole of the die 7-4 is small as in the conventional case.

A supply port 3a for supplying the high-tensile long fibers (■) to the kneading screw device 3 is provided at a distance L rearward from the front end of the kneading screw device 3 (more specifically, the front end of the threaded portion of the screw 3C) 3b. There is. And when the inner diameter of the cylinder 3g of the kneading screw device 3 is D, 1ii of L/D
The distance L is determined so that I is within 8, preferably within 5.

A high tensile strength fiber supply means 10 is provided above the supply port 3a. The high-tensile fiber supply means 10 includes a bobbin 10B, in which 1,000 to 3,000 thin high-tensile fibers are wound in a so-called roving shape. :,
It consists of a feed roller 10b that supplies the fiber bundle wound around the bobbin 10a to the supply port 3a. However, the high tensile strength fiber supply means 10 may supply fragmented high tensile strength fibers by a known supply means. Carbon fiber, aramid fiber, etc. are used as the high tensile strength fiber.

As described above, according to this embodiment, the high-tensile long fibers H can be kneaded with the plastic material without being damaged, and even if the fluidity thereof is insufficient, the high-tensile long fibers H can be stably mixed with the plastic material through the wide outlet opening 4a of the die 4. It is something that is pushed out.

The exit opening 4a of the die 4 is in the form of a rectangular slit, for example, as shown in FIG. 6. In this embodiment, there is one outlet opening 4a, but there may be more than one outlet opening 4a. Further, its shape may also be an appropriate slit-like shape other than a rectangle. In either case, the area of one outlet opening 4a is the composite material passage cross-sectional area SI.

Rolling row/L15 is a driving roller 5a and a driven roller 5
b, and a die 4 is placed between both rollers 5a and 5b.
The composite material extruded from the two is sandwiched and rolled. Both of these rollers 5a, 5b have a heating means, for example an electric heater, and the temperature thereof is regulated.

As shown in FIG. 7, the rotary cutter 6 has a driving roller 6a with a concave blade and a driven roller 6b with a convex blade, and both of these rollers 6a and 6b have heating means, such as an electric heater. , the temperature of which is regulated. The strip-shaped composite material rolled by the rolling mill 115 is cut in the front-rear direction while passing through the rotary cutter 6, and is divided into a large number of rod-shaped pieces each having a rectangular cross section.

The drive rollers 5a and 6a are driven by a power means 11 in the direction indicated by the arrow in the figure.

As shown in the figure, the pelletizer 7 is provided with a rotational force: turf a and a fixed cutter 7b, and the rotary cutter 7a is rotated in the direction of the arrow by a power means 7C to feed the pelletizer in cooperation with the fixed cutter 7b. The composite material is divided into a large number of rod shapes and then cut in the left and right direction, and the composite material is formed into rectangular parallelepiped pellets. In this case, even if the high-tensile long fibers H are aramid fibers, they can be cut because they are wrapped in plastic material.

The pellets formed in this way contain continuous high-tensile fibers between the end faces of the pellets, and the strength of molded products injection molded using such pellets is as high as that of conventional pellets. Compared to molded products containing short high-tensile fibers,
Its strength is much improved.

(Effects of the Invention) As described above, the pellet manufacturing apparatus of the present invention extrudes a composite material mixed with high-tensile fibers through a die having a slit-like opening, and then uses a rolling roll to make the thickness uniform. In addition, after cutting in the front and back direction with a rotary cutter, it is shredded with a pelletizer to make pellets, and high tensile fibers are mixed in the mixer, resulting in poor fluidity of the composite material, and it is difficult to remove from the die. This has the unique effect that the composite material can be reliably and easily pelletized after being extruded.

[Brief explanation of drawings]

The drawings all show embodiments of the present invention; FIG. 1 is a longitudinal side view of the main parts, FIGS. 2 and 3 are perspective views explaining the operation of the cross-contact screw, and FIG. 4 is a cross-sectional view of FIG. 5 is an enlarged view of point V in FIG. 1, FIG. 6 is a view taken along arrow 2 in FIG. 5, and FIG. 7 is a sectional view taken along line 2--2 in FIG. 1... Pellet production device, 2... Kneading machine, 3...
Kneading screw device, 4...Dice, 4a...Outlet opening, 5...Rolling roll, 6...Rotary cutter, 7...Pelletizer.

Claims (1)

[Claims] (1) Plastic material and high tensile strength fibers are supplied to the kneading screw device of a screw-type kneader and kneaded to form a composite material, and this composite material is extruded from a die, and the exit opening of the die is formed into a slit-like shape. At the same time, a rolling roll, a rotary cutter, and a pelletizer are installed in this order in front of this die, and the extruded composite material is cut in the front-back direction by the rotary cutter, and the composite material is cut in the left-right direction by the pelletizer. Composite material pellet manufacturing equipment characterized by molding pellets.