JPS6079934A - Manufacture of fiber-reinforced plastic bolt - Google Patents

Abstract

PURPOSE:To manufacture a plastic bolt highly reinforced with a reinforcing fiber which is lightweight and excellent in the resistance to corrosion and chemicals by a thread rolling of a cylindrical material with the surface layer made of a reinforcing fiber dispersed thermoplastic resin following the absorption of humidity to form a thread. CONSTITUTION:A cylindrical material in which at least the surface layer thereof is made of a thermoplastic resin (e.g. the one preferably containing 15-30vol% of reinforcing fiber such as polyamide) dispersed with reinforcing fiber (e.g. glass fiber) undergoes a thread rolling following absorption of humidity of form a thread. In this manner, the desired plastic bolt is obtained.

Description

[Detailed description of the invention] Technical field The present invention relates to a method of manufacturing plastic bolts, particularly.

This invention relates to a method for threading a plastic material highly reinforced with reinforcing fibers by means of a rolling process.

A metal bolt (L') has been known as a conventional bolt. This is the fastest production speed 1/%e3 for screw processing.
& Ir 1-h even 1lb years old, len 8nu
1! Although it is made with high productivity such as +, + +1-^, it has the fatal disadvantage of being heavy and having low M'f. On the other hand, plastic bolts that are lightweight and have excellent corrosion resistance are already in practical use. However, plastic materials to which rolling can be applied are limited to non-fiber reinforced plastic materials such as hard vinyl chloride resin. This is because the fiber-reinforced plastic material has a low strength of IW+ and therefore has poor plastic deformability, making it impossible to form threads by rolling, which is necessary for plastic deformability. Even if this is forcibly rolled, the threads will not form a normal triangular shape, the top of the triangle will become a single thread, and cracks will occur in the threads.

Therefore, it has low strength and cannot be used as a screw. Bolts obtained by rolling a non-fiber reinforced plastic material are inferior in two strengths. Its tensile strength is at most 4~
Since it is 6-/-, it cannot withstand use as a bolt that requires a strong fastening force.

Purpose of the Invention The purpose of the present invention is to provide a lightweight, corrosion-resistant, chemical-resistant, electric #M&I
)t+! i: *ik-1, -A, ta t JJi Io
f F h Another object of the present invention is to provide a method for manufacturing a high-strength single-stick bolt by thread rolling, which is the most economical method for thread processing.

SUMMARY OF THE INVENTION The fiber-reinforced glass bolt of the present invention is produced by absorbing moisture from a cylindrical material in which at least the surface layer is made of a thermoplastic resin in which reinforcing fibers are dispersed.

It includes forming a thread by subjecting it to a rolling process.

Thereby, the above objective is achieved.

Examples of reinforcing fibers include LF Fusufuiipa.

There are inorganic fibers such as carbon fiber, boron fiber, and next-generation silicon fiber; and organic fibers such as abmid fiber. It is also possible to use a mixture of two or more of these fibers. There is no particular restriction on the length of the fibers, as long as they can be dispersed in the thermoplastic resin molded into a cylindrical material. These reinforcing fiber thermoplastic resins are melt-mixed with a mixing device such as an extruder and uniformly dispersed in the resin. This reinforcing fiber has 10 to 40
% by volume, preferably in the range of 15-85% by volume. If the fiber content is too low, high strength plastic Pol F
can't get it. If the amount of cellulose 1ik is too large, it becomes brittle and the reinforcing effect decreases.

Examples of thermoplastic resins include polyamide.

Polyethylene terephthalate, polybutylene terephthalate
-glue, polyaceter μ, etc. are used.

Needless to say, there is no need to be limited to this. These resins may be mixed with fillers, treatment agents for improving adhesion to fibers, flame retardants, antioxidants, etc., as required.

At least the surface layer of the cylindrical material used in the present invention is composed of thermoplastic resin in which the reinforcing fibers are dispersed, and the center portion may have the same structure as the surface layer. The core material may be made of a high-strength metal material such as iron, a fiber-reinforced thermosetting resin material, or the like. When a core material is used, the surface of the core material may be provided with irregularities or grooves to improve bondability with the thermoplastic resin.

The moisture absorption treatment in the present invention may be carried out to the extent that the plastic material can exhibit plastic properties.

In particular, it is sufficient that at least the surface layer to undergo the deformation process of one cylindrical material in the rolling process is subjected to moisture absorption treatment. Moisture absorption treatment includes, for example, immersion in water.

Methods include immersion in hot water at 50 to 80°C and immersion in water or hot water under pressure. The thickness of the surface layer of the cylindrical material subjected to deformation varies depending on the dimensions of the screw.
In the case of pol), it is about O, +S ~ 0.8 ml. It is sufficient that the portion 5 absorbs moisture during the rolling process, and the moisture absorption rate is 2. For example, for fiber reinforced polyamide,
In the case of MIO Popbol's cylindrical material with a diameter of about 9 nm, the 0.81 g thick portion of the surface layer accounts for 1.6% by weight or more, preferably 2% by weight or more.

It only needs to absorb moisture. If the moisture absorption amount is less than 1.5% by weight, a sufficient thread shape cannot be formed by rolling.

does not need to be special, and a rolling machine such as a round die rolling machine or a flat die rolling machine that is commonly used for forming the thread B of metal screws can be used as is.

Example The present invention will be described below with reference to Examples.

Example 1 First, resin polyamide (Amitsun Nylon 6 manufactured by Toshi Oe)
6),! = 18 μm diameter, 6 MM + Wogg glass fibers were dry blended at a volume ratio of 70:80, and this was molded into a round bar with a diameter of 9 mm using an extruder.

Next, this was cut into a length of 1ocwi to obtain 8 wooden cylindrical materials. This was immersed in water for 12 hours.

Five of them were threaded using a rolling machine equipped with KMIO thread dies. The obtained 1Gα length M
The IO bobbin screw thread shape was visually observed. At the same time, attach nuts to both ends of the bolt to meet JIS 8 1051.
A tensile test was conducted according to the method described in 2007, and the breaking strength was measured. 5
The average values for the books are shown in the table below and include not only large tensile loads, but also the maximum tensile loads at which the threads are destroyed and the bolt is about to be pulled out of the nut. Furthermore, the moisture content of the cut IO1 was measured by locking the surface layer of each of the eight remaining cylindrical materials that had not been subjected to rolling processing over a distance of 0.8 m. The average values for the eight trees are shown in the table below.

Example 2 Everything was the same as in Example 1 except that the immersion time in water was 48 hours.

Example 8 The mixing volume ratio of polyamide resin and glass fiber was 85:1
Everything is the same as in Example 1 except that it is set to 5.

Example 4 Mixing volume ratio of polyamide resin and glass fiber was 89+1
Everything is the same as in Example 1 except that it is set to 1.

Example 5 The mixing volume ratio of polyamide resin and glass fiber was 62:8
Comparative Example 1 Same as Example 1 except for B.
c! A cylindrical material with a length of II is directly subjected to rolling processing. Everything else is the same as in Example 1.

Comparative Example 2 Same as Example 1 except that the immersion time in water was 8 hours.
It is similar to

Comparative Example 3 Mixing volume ratio of polyamide resin and glass fiber was 95:5
Everything is the same as in Example 1 except for the above.

Comparative Example 4 A mixture of polyamide resin and glass fiber with a ratio of 55
:45 except that everything is the same as in Example 1.

Example 1 2.1 Good 1250 2 8.2 Good, Good 1B00 Example 3 2.3 Good 1100 42.4 Good 1050 Comparative Example I O08 Thread crest is double 7502 1.4
Two thread crests 790 32.8 Good 500 4 1.8 Threads cannot be formed - Effects of the invention According to the present invention, as described above, threads are formed by rolling on a glass material highly reinforced with one reinforcing fiber. It becomes extremely easy to perform Jyokai Kata. Since thread forming by rolling is highly productive, bolts can be produced economically.

Moreover, the thread shape of the resulting glass thread A/) is good, and there is no occurrence of cracks or cracks in which the top of the thread has two threads. Moreover, the bolt is high strength and
It has all the characteristics of fiber-reinforced glass materials, such as being lightweight and highly tactile.
IL

Claims (1)

[Scope of Claims] 1. A fiber comprising a cylindrical material, at least the surface layer of which is composed of a thermoplastic resin in which reinforcing fibers are dispersed, which is subjected to a rolling process after absorbing moisture to form a thread. Method of manufacturing reinforced plastic bolts. 2. The method described in claim 1, wherein the thermoplastic resin contains reinforcing fibers in an amount of 10% or more by volume.