JPS61199931A - Manufacture of fiber reinforced plastic threaded product - Google Patents

Abstract

PURPOSE:To produce the twill weave effect of yarn tapes and consequently prevent the strength of screw thread from deteriorating by a method wherein the yarn tapes impregnated with thermosetting resin are filament-wound onto a cylindrical mandrel with a twill angle. CONSTITUTION:A necessary number of fraying prevented yarn tapes 1 are pulled out of tape bobbins 2, gathered in an arbitrary number of units and paralleled by a comb-like guide 3, inpregnated with thermosetting resin in a resin path 4, in which a tape hold-down roller 5 is provided in order to completely immerse the tapes in the resin and at the same time to degas bubbles in the tapes. A band-shaped group of resin-impregnated tapes are wound in parallel state by a traversing gear 7 with an arbitrary crossing angle, preferably with an angle of 60-87.5 deg.. In a thread-chased bolt, reinforcing fibers enter toward threads with complicate directions from the thread core, resulting in strongly binding the resin in thread portion with said interlocking fiber group and realizing neither omission of fibers nor molding with the inclusion of the mixture of flocks and the resin and consequently obtaining a cylinder with favorable quality having no deformation of threads.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of manufacturing a fiber-reinforced plastic screw product. More specifically, a yarn tape such as glass fiber is impregnated with a thermosetting resin, wound around a mandrel, cut in the axial direction to form a prepreg, and a large number of prepregs are stacked and cured, and then cut into a desired shape. It is characterized by this.

2. Description of the Related Art Many patent applications have been filed and various technologies have been disclosed regarding fiber-reinforced plastic screw products and their manufacturing methods.

These manufacturing methods can be broadly classified into methods in which glass fiber rovings are impregnated with resin, molded in a cylindrical mold of arbitrary thickness, and then machined to create screw products such as bolts. A method of thread rolling a mixture of short fibers and thermoplastic resin into arbitrary dimensions using a rolling mold. There are three methods: a method in which bolts and nuts are cut out from molded plates made by impregnating yarn cloth such as glass fiber with resin, stacking them, and hardening them under pressure and heat.

In addition, recently, the present inventor has provided a method for manufacturing an internal thread using roving as a fiber reinforcing material (Japanese Unexamined Patent Publication No. 59-1
No. 28223). That is, the gist is that a glass roving is wound around a cylindrical or polygonal tube-shaped mandrel at a winding angle using a filament winding machine, and then the glass roving is cut in the axial direction to form a prepreg.
Stack the required number of prepregs and press-form them, F.
After obtaining the R and P plates, thread cutting is performed in the plate thickness direction,
It manufactures nuts and female threads.

Problems to be Solved by the Invention The screws obtained by these conventional methods each have unique performance due to their respective methods.

Further improvements are desired as a replacement for conventional metal screws and for use in new fields. Further, research is being conducted to further reduce labor in these manufacturing methods.

Incidentally, screw products made by thread-cutting an FRP rod using roving as a reinforcing material have the disadvantage that the roving is cut off during thread-cutting, resulting in a significant deterioration in thread strength. Next, in the method of thread rolling a mixture of short fibers and resin using the thread rolling method, fiber breakage at the threaded portion was improved because no thread cutting was performed, but the tensile strength in the axial direction of the thread was reduced. There are weak drawbacks. Furthermore, screw products such as bolts and nuts, which are made by cutting FRP boards made by stacking and molding resin-impregnated yarn cloth, have excellent strength because reinforcing fibers are arranged both in the direction of the thread and in the direction of the thread axis. Although it is a threaded product, it has the drawback of being extremely expensive to produce.

In the above-mentioned method invented by the present inventor, the glass fiber roving enters the screw thread, and the next layer of roving having the opposite winding angle presses the inserted roving layer, thereby destroying the thread. However, if the thermosetting resin is mixed into the roving unevenly or if the resin is impregnated unevenly, the bond between the roving layers may deteriorate. There is a problem in that the twill weave becomes incomplete and the effect of the twill weave by the filament winding method cannot be achieved, and the thread strength deteriorates.

Means for Solving the Problems The inventor of the present invention has made repeated studies to improve these problems.
The present invention provides a novel method for manufacturing screw products using yarn tapes such as glass fibers as reinforcing fibers.

That is, the present invention.

A yarn tape coated with a resin to prevent fraying is impregnated with a thermosetting resin, and then wound around a cylindrical or polygonal mandrel at a winding angle using the filament winding method to obtain a desired thickness. This method of manufacturing a fiber-reinforced plastic screw product is characterized in that the fiber-reinforced plastic molded plates are cut into prepregs, and the prepregs are stacked and heated under pressure to perform thread cutting.

The present invention will be further explained below.

As described above, the most distinctive feature of the present invention is that the reinforcing fibers that are cross-wound around the cylindrical anvil by the filament winding method are not rovings as in the past, but yarn tapes, and furthermore, this yarn tape is coated with a resin to prevent fraying. It is where it is applied.

The fibers that make up the yarn tape have a tensile strength of 10
Glass fibers, carbon fibers, aramid fibers, etc. having a Young's modulus of 6000 Kff/- or more and a Young's modulus of 6,000 Kff/- or more are used, and glass fibers are preferred.

Yarn tape is woven into a tape shape from the beginning, and the tassels are obtained by cutting yarn cloth.

It is a so-called tape-like material that is woven into a yarn tape by cutting the yarn cloth arbitrarily.

The resin for coating the yarn tape has good compatibility with the thermosetting resin used for molding, has good adhesion, and does not deteriorate the physical properties of the molded product, and preferably a thermoplastic resin is used. Preferably less than 10% by weight,
Preferably, the amount is less than 5% by weight.

Incidentally, a preferred specific example of a resin-coated glass yarn used in the present invention to prevent fraying is a 1% tuft of glass fabric or cut glass as disclosed in Japanese Patent Application No. 59-15563. Tape that heat-melts and impregnates the cut part of cloth with polyester resin to prevent it from fraying, or tape made from glass woven fabric that is cut into a tape shape after preventing it from fraying with polyester resin, or tape made from glass woven fabric. When cutting into shapes, only the cut part is coated with a resin and then cut.These tapes include those that are woven from the beginning as yarn tapes, the selvage parts that are cut from yarn cloth, and the tapes that are made by cutting that part after coating the cut part with resin. A yarn tape obtained by any method, such as one obtained by aggressively cutting a cloth into a tape shape, may be used.

The thermosetting resin used in the present invention is preferably an epoxy resin in terms of physical properties, but examples thereof include unsaturated polyester resin, vinyl ester resin, and phenol resin.

Thermosetting resins can also be used.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a perspective view showing a prepreg manufacturing method according to the method of the present invention. A necessary number of tape grilles 2 are pulled out, and the comb-like guides 3 are used to arrange the tapes in arbitrary number units, and in a retin bath 4, they are impregnated with a thermosetting resin. At this time, the width of each yarn tape pulled out from the tape grille is generally from S to 30 m wide, taking into consideration the relationship between conformability, fluidity, and workability during molding. Usually, 3 to 10 pieces of tape are pulled together and guided into the middle method register/pass using a comb tooth guide so as to form a band of 10 to 1001E11.

A tape pressing roller 5 is provided in the resin bath 4 to completely immerse the tape in the resin and defoaming the air bubbles in the tape.

A group of band-shaped tapes impregnated with resin are placed in parallel,
It is wound around the mandrel 6 at an arbitrary angle by the traversing device 7.

The width of the band-like tape group varies depending on the width of each tape and the number of tapes to be assembled, but it should be designed to have a width of 9 bands in consideration of fluidity that allows the tape group to fit during pressure molding. is preferred.

Figure 2 shows the state in which the yarn tape is wound around a mandrel, with the forward tape (travel angle 0) and the return tape (travel angle 0') forming twills in opposite directions. The tapes overlap each other.

FIG. 3 shows a method of obtaining a sheet-like prepreg by incising a prepreg made of yarn tape cross-wound around an anvil along the axial direction of the anvil 6 at an incision site 8 with a cutter knife or the like.

At this time, the thickness of the tape wrapped around the mandrel varies depending on the diameter of the mandrel, but when it is cut into a sheet prepreg, wrinkles do not occur and the tape group within the sheet unit has the fluidity of the resin. The appropriate thickness is such that it can be moved in the width direction to some extent, and is usually 3 to 15 m thick.

Figure 4 shows the arrangement state of the yarn tape of the sheet-like prepreg. In this way, multiple sheets of prepreg consisting of a group of resin-impregnated yarn tapes that are twilled at an arbitrary angle and overlapped are made as needed. When stacked and cured under heat and pressure, a fiber-reinforced plastic plate is obtained.

At this time, the heat curing conditions vary depending on the reinforcing fibers used, the material of the curable resin, the mixing ratio, etc., but for example, in the case of glass yarn tape impregnated with epoxy resin, it is 10-100
A method is adopted in which a molded plate is obtained by applying a pressure of Kq/- and holding it for 10 to 60 minutes.In addition, in this case, the glass fiber in the glass fiber reinforced plastic plate has a weight of 55 to 78%, and a strength of preferable.

However, these conditions are only S1, and the present invention does not particularly limit these conditions.

A bolt made of glass fiber reinforced plastic can be obtained by cutting the plate-shaped molded product into a rod shape and threading it.

Effects of the Invention In the glass fiber reinforced plastic bolt of the present invention obtained as described above, the molded plate as its substrate is formed by two mutually orthogonal groups of fibers constituting the yarn tape itself and the cross-winding of the tape. In addition, two groups of cross-cutting fibers are arranged and alternately overlapped, and the next bolt that is threaded from this molded plate has reinforcing fibers inserted at a complicated angle from the part where it is threaded in the threading direction. The resin in the threaded portion is firmly constrained by these interwoven fiber groups, resulting in a bolt with excellent thread strength.

In addition, since the present invention uses a resin-coated yarn tape that prevents fraying, the fibers do not fall off, and the mixture of fiber waste and resin does not get caught up in the molding, so it is possible to produce bolts of good quality with no thread loss. You can get it.

In addition, in detail regarding a female threaded product such as a nut, when a female thread is provided in a hole cut out in the thickness direction of the fiber-reinforced plastic plate of the present invention, the yarn tapes are stacked in the thickness direction (screw axial direction), The yarn tape is twilled in the threading direction, and the fiber rows are arranged in a more complex manner, resulting in a nut with excellent torque strength.

As described above, the screw products of the present invention are not only superior in terms of quality, but from the viewpoint of rational product production, the filament winding prepreg lamination of the yarn tape of the present invention is superior to the conventional yarn cross lamination method. This method greatly reduces the number of man-hours required to obtain a molded plate of any desired thickness. Particularly in terms of cost, the production cost can be dramatically reduced if the slit yarn tape used as a raw material is used, for example, by cutting tape on both ends of yarn cloth, which has conventionally been disposed of.

Furthermore, the manufacturing method thereof also has the following effects.

When a yarn tape that has not been protected from fraying is cross-wound using a filament winding machine, it will be rubbed, twisted, and rubbed by the tape presser roller, comb-toothed guide, and traverse arm in the resin bath, causing the glass yarn tape to become fuzzed, frayed, and There is some fiber shedding, and these fiber wastes adhere to the resin-impregnated tape and are wound and formed, so the fiber threads of the tape have
These unconnected fiber waste portions deteriorate the physical properties of the reinforced plastic and cause the threads to collapse during the thread cutting process.

In other words, the yarn tape may become fluffed, frayed, etc. due to rubbing, rubbing, twisting, etc. by the tape presser roller in the resin bath, the comb-toothed guide that aligns the tape to arbitrary gaps, and the traverse swinging arm before being cross-wound onto a cylindrical annovil. A fiber-reinforced plastic with no fiber shedding or damage is impregnated with a thermosetting resin, cross-wound, and cut in the axial direction to form a sheet-like prepreg. Multiple layers of this prepreg are laminated and cured under pressure. The plate has excellent strength, and after cutting this plate into rod shapes of arbitrary dimensions, threaded reinforced bolts are cut out from the plate formed by roving.It is stronger than nine screws and has a stable quality screw product. It exists because it can be manufactured.

For example, for male threaded products such as bolts, a molded plate using yarn cloth as the reinforcing fiber is cut out into a prismatic shape, which is then made into a round bar.
After thread cutting, conventional bolts consist of fibers arranged in the direction of the screw axis and fibers extending from the threaded part in the direction perpendicular to this direction, and have excellent strength. A bolt cut out in the same manner from the fiber-reinforced plastic plate of the present invention has a reinforcing yarn tape arranged in a twill pattern, and first, the yarn tape is arranged in a twill pattern between the woven fiber rows and the twill pattern of the yarn tape itself. Since the fiber rows are overlapped and arranged, the fiber rows have a plurality of arrangement angles both in the screw axis direction and in the screw exit direction. Therefore, it is possible to obtain a bolt having stronger tensile strength and thread shear strength than the conventional bolt using the yarn cloth as a reinforcement material. Another problem in the manufacturing process is that these fiber wastes increase the viscosity of the resin in the resin bath.During equipment operation, fiber waste must be constantly removed to control resin viscosity, and at the end of each day, the resin path must be cleaned. If the resin was not removed, the viscosity would increase and the equipment could not be restarted the next day.

In the present invention, the above-mentioned drawbacks are overcome, and the viscosity control of the resin in the resin bath is greatly improved, so that the resin in the resin bath can be reused when restarting operations the next day without having to remove it at the end of the work day. became.

[Brief explanation of drawings]

Fig. 1 shows a manufacturing device that shows part of the manufacturing method of the present invention, Fig. 2 shows a mandrel wrapped with yarn tape, Fig. 3 shows a method for obtaining prepreg, and Fig. 4 shows a sheet. The figure shows the alignment state of the yarn tape of shaped prepreg. ! = Glass yarn tape with fray prevention 2: Tape grill 3: Comb-shaped tape guide 4: Resin bath (resin dipping tank) 5: Tape presser roller 6: Mandrel 7: Traverse device (traverse arm) 8: Incision site 9 : Tape angle going to sheet prepreg 02 θ′ : Return tape angle 2nd
Figure 3v! I Figure 4 Procedural Amendment Statement March 27, 1985

Claims (1)

[Claims] A yarn tape coated with a resin to prevent fraying is impregnated with a thermosetting resin, and then wound around a cylindrical or polygonal mandrel at a winding angle using the filament winding method to obtain a desired thickness. A method for producing a fiber-reinforced plastic screw product, which comprises cutting a fiber-reinforced plastic molded plate by stacking the prepreg and heating and pressurizing the fiber-reinforced plastic molded plate.