JPH11280732A - Resin joint and manufacture therefor, and connector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a large tensile strength by providing the female screw parts in a cylindrical main body, and arranging a reinforcing material in the shaft direction in a state of being integrally joined to the thick wall part or the outer peripheral part of the cylindrical main body. SOLUTION: A joint 1 has a pair of female screw parts 3 in the axial direction of a resin cylindrical main body 2, and a cylindrical reinforcing material 4 is arranged in the axial direction over its both ends in the thick wall part of the cylindrical main body 2 in an embedded state. Iron, aluminum or FRP having axial directional tensile strength larger than a resin material constituting at least the cylindrical main body 2 are used as the reinforcing material 4. The reinforcing material 4 is incorporated into the joint 1 by insert molding, one end is held on its both ends or in a cantilever shape to hold the reinforcing material 4 in an insert position, and a female screw forming male screw-shaped core is used at molding time, but when a female screw is formed of the other means, the core is not required. By such constitution, large tensile strength can be realized, and the tensile strength can be easily adjusted by selecting the reinforcing material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin-made joint, a method of manufacturing the same, and a connector, and more particularly, to a nut-type joint (a female screw for screwing a member equipped with a male screw) related to ordinary resin injection molding. (The same shall apply hereinafter.)
The present invention relates to a resin joint having significantly higher tensile strength as compared with the above, a method of manufacturing the same, and a connector in which a male screw-equipped member is threadably connected by the resin joint.

[0002]

2. Description of the Related Art In various industrial fields, when it is desired to connect two or more members, these members may be provided with external threads and connected via a nut type joint. As an example, in order to drive rock bolts for ground reinforcement used in excavation of tunnels etc. deeper into the ground for the purpose of shortening the construction period etc., a male screw is formed at the end and a nut type joint is used. May be longer.

[0003] Nut joints are often required to have high tensile strength for various reasons. For example, an elongated lock bolt is required to have resistance to pulling out of the ground, and therefore, a nut-type joint may be required to have ideally tensile strength not inferior to that of the lock bolt itself.

Therefore, conventionally, a metal-type (typically, iron-made) nut type joint having excellent strength has been widely used. However, metal parts are heavy and generally high in production cost because they are cut products. In addition, for joints for specific applications such as rock bolts, strength deterioration due to rusting in the soil poses a problem. In some cases, the tunnel excavator was damaged in some applications.

[0005]

On the other hand, in a resin-made nut type joint manufactured by injection molding,
Lightweight and low production cost, there are no problems such as rust and damage to excavator. However, the tensile strength is insufficient due to the material, so that the practical use remains unsatisfactory for uses such as connection of a lock bolt.

In recent years, a so-called FRP resin product in which a glass long fiber bundle is impregnated with a resin and drawn is provided. These are light weight, non-rust, peculiar to resin products,
While having the advantage of rigidity that does not damage an excavator or the like, it has significantly higher tensile strength in the arrangement direction of the long glass fiber bundle than a resin injection molded product. However, the pultrusion molding method is not suitable for molding a shape having irregularities in the axial direction, such as a female screw portion, including the case of molding a cylindrical body using a core rod. Forming the female screw portion on the FRP product by intermediate machining in a separate process also has significant disadvantages in terms of cost and strength reduction.

Accordingly, the present invention is to solve the problem of providing a resin-made nut type joint having a large tensile strength, a method of manufacturing the same, and a connecting member of a male screw equipped member using the same at low cost. And

[0008]

Means for Solving the Problems (Structure of the First Invention) The structure of the first invention of the present application (the invention as set forth in claim 1) for solving the above-mentioned problems has a cylindrical main body provided with a female screw portion. A resin-made joint, wherein a reinforcing member is provided along the axial direction in an integrally joined state on a thick portion or an outer peripheral portion of the tubular main body.

(Structure of the Second Invention) The structure of the second invention of the present application (the invention according to claim 2) for solving the above problems is as follows.
In the cavity of the mold for injection-molding the resin joint according to the first invention, the reinforcing material is held at an insert position corresponding to a thick portion or an outer peripheral portion of the cylindrical main body, and is melted into the cavity. This is a method for manufacturing a resin joint, in which the resin is injected to manufacture the resin joint of the first invention.

(Structure of Third Invention) The structure of the third invention of the present application (the invention according to claim 3) for solving the above problems is as follows.
It is a joint made of FRP which has a female screw part in a cylindrical main part, wherein said female screw part is formed by a male screw provided in a core rod for forming said cylindrical main part.

(Structure of the Fourth Invention) The structure of the fourth invention of the present application (the invention according to claim 4) for solving the above problems is as follows.
Impregnating the glass filament bundle with resin and using a core rod
A method of manufacturing a resin joint, wherein the core rod is provided with a male screw to be a rotary extraction type when the FRP tubular main body of the invention is subjected to the extrusion molding.

(Structure of Fifth Invention) The structure of the fifth invention of the present application (the invention according to claim 5) for solving the above problems is as follows.
A connecting body formed by screw-connecting a male screw equipped member with the resin joint according to any one of the first invention and the third invention.

(Structure of the Sixth Invention) The structure of the sixth invention of the present application (the invention according to claim 6) for solving the above problems is as follows.
A fifth aspect of the present invention is the connecting body, wherein the male screw equipped member is a lock bolt.

[0014]

(Operation / Effect of the First Invention) In the first invention, since the reinforcing member is provided along the axial direction in the thickened portion or the outer peripheral portion of the cylindrical main body in an integrally joined state. , The strength of the reinforcing material is added to the strength of the tubular body,
Realizes high tensile strength of resin joints. The tensile strength can be easily adjusted by selecting the reinforcing material. Moreover, at this time, advantages inherent in resin products such as lightness, rust resistance, and rigidity not to damage an excavator are not sacrificed.

When the reinforcing material is provided at the thick portion of the cylindrical main body, it is not exposed to the outside. Therefore, even if a rust-generating metal reinforcing material is used, there is no possibility that the strength is reduced due to rust.

(Operation and Effect of the Second Invention) In the second invention, since an ordinary resin injection molding method is used except for the method involving the insertion of a reinforcing material, the advantages of the low cost and simple injection molding method are utilized. The resin joint of the first invention can be manufactured.

(Functions and Effects of Third and Fourth Inventions) In the third and fourth inventions, since a male rod is provided on a core rod for forming a cylindrical body made of FRP and a rotary pull-out type is used, a conventional method is used. The internal thread portion, which has been difficult with the pultrusion molding method, can be molded without difficulty. In addition, since the core rod originally required for forming the cylindrical main body is used, the cost is not increased in terms of required facilities and processes, and the strength is not reduced as in the cutting method.

(Function / Effect of the Fifth Invention) According to the fifth invention, a connection body having excellent tensile strength can be easily provided at a low cost at the connection portion.

(Function / Effect of the Sixth Invention) According to the sixth invention, a long lock bolt having excellent tensile strength even at the connection portion can be easily provided at low cost.

[0020]

Next, embodiments of the first invention to the sixth invention will be described. In the following, simply "the present invention"
When it says, it refers to 1st invention-6th invention collectively.

[Resin Joint] The resin joint of the present invention is a joint having a female threaded portion in a cylindrical main body. The joint is made by injection molding as in the second invention and is drawn by molding as in the fourth invention. And those made of FRP.

The type of resin constituting these resin joints is not limited, and any thermoplastic resin such as vinyl chloride resin, polycarbonate resin, polypropylene resin or the like, or epoxy resin, phenol resin, unsaturated polyester resin or the like can be used. Those using an arbitrary thermosetting resin, or those containing short glass fibers and other reinforcing materials and various additives can be used.

In general, two or more female screw portions are generally formed as a joint. However, when a female screw portion capable of screwing separate male screw-equipped members from both sides is provided, There may be a case where the female screw portion is single, such as a case where the female screw portion is connected by means other than screwing.

The shape of the cylindrical main body is typically a linear cylindrical shape, such as a joint for a lock bolt, in which two male screw-equipped members are linearly connected. Offset and parallel connection of equipment members, L-shape that can be connected at right angles or other predetermined angles, 3
There may be a T-shape that can connect the pieces in a plane, a trifurcated shape that can be connected in a three-dimensional direction, and a cross-shape that can connect four pieces.

[Resin Joint of the First and Second Inventions] In the resin joint of the first invention, a reinforcing material is formed along the axial direction in an integrally joined state with a thick portion or an outer peripheral portion of a cylindrical main body. Is provided.

Here, the "thick portion" means an intermediate portion between the inner peripheral surface and the outer peripheral surface of the cylindrical main body, and the reinforcing material provided in the thick portion is in a state embedded in the cylindrical main body. Since it is not exposed on the inner and outer peripheral surfaces, even a reinforcing material such as iron can be used without fear of rusting. In this case, even if one end or both ends of the reinforcing member are slightly exposed in the axial direction from the cylindrical main body, rusting at that portion does not affect the strength, so that it does not matter.

Next, the "integrally joined state" refers to a joined state in which the resin material and the reinforcing material can bear a load like a single member against the tensile force acting on the cylindrical main body. The following joining forms can be exemplified. By combining two or more of these joining forms, a more effective joining state can be achieved.

Resin material and reinforcing material (particularly, resin reinforcing material)
Are surface-bonded without any gap by injection molding of a resin material. This joining mode is particularly effective when the joining area is increased by providing a tubular reinforcing member at the thick portion or the outer peripheral portion (particularly, the thick portion) of the tubular main body of the joint. In the case of a resin-made reinforcing material such as made of FRP (particularly, made of FRP using the same resin as the resin material), the interface with the resin material substantially disappears,
Particularly large effects can be expected.

The resin material and the reinforcing material are at least partially meshed with each other by irregularities in the radial direction. As a typical example of this bonding mode, a hole or a notch having a cut surface in the radial direction is provided in the reinforcing material, and a form in which the injection resin is allowed to penetrate there, or a radial unevenness or projection is provided in the reinforcing material. The form can be considered. In the case of using the tubular reinforcing material, the provision of the hole or the notch may be necessary in order that the reinforcing material does not prevent the filling of the resin.

Since the reinforcing material is a porous material or a structure rich in voids such as a fiber assembly, the voids are filled with the resin material, and the reinforcing material and the resin material form an integrated structure.

It is sufficient that the reinforcing material is provided at least in a length that covers a portion of the cylindrical main body to which a load is substantially applied, but the reinforcing effect is greatest when provided at both ends in the axial direction of the cylindrical main body.

The material and shape of the reinforcing material are not limited as long as the reinforcing effect is recognized. Examples of a few materials of the typical reinforcing material include metal, FRP, and a knitted fabric made of glass fiber. Examples of the shape of the reinforcing material include a rod-like shape, a plate-like shape, a curved plate-like shape having a circular cross section at an arbitrary angle, and a tubular shape. In these shapes, those provided with the above-described hole or notch for injecting the injection resin are particularly preferable.

In the second invention, the reinforcing material is incorporated into the resin joint by insert molding. In the insert mold, in order to hold the reinforcement at the insert position,
Both ends may be held, or one end may be held in a cantilever shape. Normally, in addition to the reinforcing material inserted during molding, a male screw core for forming a female screw is also used, but when forming a female screw by any other means, the male screw core is unnecessary. is there.

[Resin Joints of the Third and Fourth Inventions] The resin joints of the third and fourth inventions are made of an FRP made by impregnating a glass long fiber bundle with a resin and drawing it out. The main body is provided with a female screw portion. A male screw for forming the female screw portion is provided on a core rod for forming a cylindrical inner peripheral portion of the main body, and the core rod is formed by drawing a core rod or a resin joint along a thread groove after drawing. It is a method of extracting while rotating.

According to this method, the female screw portion can be formed with high accuracy without reducing the strength of the cylindrical body and the female screw portion made of FRP. Rotational extraction of the core rod may be performed artificially, or may be automated by connecting a core rod rotational extraction device to the pultrusion molding line.

[Connection Body of Fifth and Sixth Inventions] One of the representative examples of the connection body is a resin or metal rod-shaped or pipe-shaped lock bolt provided with a male screw portion, made of the resin of the present invention. This is an elongated lock bolt that is linearly connected to two or more joints.

However, the type of the male screw member is not limited, and the male screw member does not necessarily have to have a linear shape. L of the cylindrical body of the resin joint described above
According to the embodiments such as a character shape, a T shape, a trifurcated shape, a cross shape, etc., the number of connected male screw portion-equipped members and the connection direction are also various.

[0038]

Next, an embodiment of the present invention will be described with reference to the drawings.

(Embodiment 1) A joint 1 shown in FIGS. 1 (a) and 1 (b) has a pair of female screw portions 3 in the axial direction of a cylindrical body 2 made of resin and has a cylindrical shape. A tubular reinforcing member 4 is provided in the thick portion of the main body 2 along the axial direction across both ends thereof in an embedded state. The reinforcing member 4 is made of a solid material (iron, aluminum, FRP, or the like) having a tensile strength in the axial direction greater than at least the resin material forming the cylindrical main body 2. Since both end portions of the reinforcing member 4 are portions that have been clamped by the molding die during injection molding, they protrude slightly from the cylindrical main body 2.

[0040] Such a tubular reinforcing material includes, for example, FIG.
As shown in FIG. 5, there is provided a void portion serving as a passage for the injection resin, such as a notch 6 provided in a peripheral wall portion of a reinforcing material 5 made of iron or aluminum. After the resin is injected, the voids are filled with the resin material, so that the resin and the reinforcing material are strongly integrated. The FRP reinforcing member 7 shown in FIG. 3 has a hole 8 provided in a cylindrical peripheral wall portion. The function and effect of the hole 8 are the same as those of the notch 6.

(Embodiment 2) FIG. 4 shows a state in which a tubular reinforcing member 9 is embedded in a thick portion of a resin-made tubular main body 2 constructed in the same manner as in Embodiment 1 along both ends thereof along the axial direction. 2 shows a manufacturing state of the joint 1. This reinforcement 9
As shown in FIG. 5, a glass fiber is knitted and woven in a tubular shape, and both ends thereof are clamped by an insert molding die under a pressing force in the direction of the arrow. Since the injected molten resin penetrates into the inside of the reinforcing material 9, the resin and the reinforcing material are strongly integrated.

Further, since the reinforcing member 9 is clamped in the compressed state as described above, the molten resin does not leach out of the molding die from that portion. When the injection hole of the mold exists only on one of the inner peripheral side and the outer peripheral side of the reinforcing member 9, the reinforcing member 9 may be provided with a hole serving as a passage for the injection resin.

(Embodiment 3) In FIG. 6, a cylindrical reinforcing member 10 is integrally formed on the outer peripheral portion of a resin-made cylindrical main body 2 constructed in the same manner as in Embodiment 1 and along both ends thereof along the axial direction. 1 shows a joint 1 provided in a joined state. This reinforcing material 10 is inserted into the inner peripheral wall of the cavity of the mold.
The reinforcing member 10 is made of FRP, and is well integrated with the injected molten resin, and thus is strongly integrated with a joined state in which the interface with the tubular main body 2 has substantially disappeared.

(Embodiment 4) FIGS. 7 to 9 show an embodiment of a joint 11 according to pultrusion molding, and a single female threaded portion extending over both ends in the axial direction is provided on an inner peripheral portion of a cylindrical main body 12 made of FRP. 13 are formed. Then, a pair of male screw-equipped members (not shown) are screwed from both ends of the female screw portion 13 to an appropriate depth.

The method of manufacturing the joint 11 is as shown in FIG. 8. First, a number of long glass fiber rovings 14 are passed through a molten resin tank 15 to be impregnated with a thermosetting molten resin.
After adjusting the amount of impregnated resin with a squeeze 16 or the like, a male screw of the same pitch is provided over the entire length, and is arranged under the guide of a guide 18 so as to surround the core rod 17 which is intermittently driven and rotated at a fixed position. In a state where the outer peripheral portion of the core rod 17 is covered, it is introduced into a round-shaped press groove 20 of a heated press die 19 shown in detail in FIG.

An FRP having a female thread 13 on the outer periphery of the
Is formed and solidified by thermosetting of the molten resin. When the core rod 17 is driven and rotated,
The upper die 21 of the press die 19 rises and the take-up device 22
Pulls the joint 11 at a speed synchronized with the rotation speed of the core rod 17 by the length corresponding to the completion of molding.

Finally, the joint 1 having passed through the take-off device 22
1 is cut into a circle by the revolving cutter 23 and is pulled out from the core bar 17 while being rotated manually or by appropriate mechanical means. The drive rotation of the core rod 17 is extremely effective in forming a female screw with high shape accuracy and dimensional accuracy in the FRP material.

(Embodiment 5) FIG. 10 shows an elongated lock bolt 26 in which two lock bolts 25 each having a male screw 24 are connected using the above-mentioned joint 1 or joint 11. FIG.
Shows a cross section taken along line AA of FIG.

[Brief description of the drawings]

FIGS. 1 (a) and 1 (b) show a resin joint according to an embodiment, and FIG. 1 (a) is a view showing a half section thereof;
(B) is a figure which shows the center longitudinal half cross section of FIG.1 (a).

FIG. 2 is a perspective view of a reinforcing member according to the embodiment.

FIG. 3 is a perspective view of a reinforcing member according to the embodiment.

FIG. 4 is a half sectional view showing a manufacturing state of the resin joint according to the embodiment.

FIG. 5 is a perspective view of a reinforcing member according to the embodiment.

FIG. 6 is a half sectional view of a resin joint according to the embodiment.

FIG. 7 is a half sectional view of the resin joint according to the embodiment.

FIG. 8 is a view showing a manufacturing process of the resin joint according to the example.

FIG. 9 is a perspective view of a press mold used in an example.

FIG. 10 is a view showing the elongated lock bolt according to the embodiment in a partially sectional state.

FIG. 11 is a sectional view taken along line AA of FIG. 10;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1,11 Joint 2,12 Tubular main body 3,13 Female thread part 4,5,7,9,10 Reinforcement material 17 Core rod 26 Lengthening lock bolt

Claims (6)

[Claims] 1. A resin joint having a female threaded portion on a cylindrical main body, wherein a thick portion or an outer peripheral portion of the cylindrical main body has:
A resin joint, wherein a reinforcing material is provided along an axial direction with an integrally joined state. 2. In a cavity of a mold for injection-molding the resin joint according to claim 1, the reinforcing member is held at an insert position corresponding to a thick portion or an outer peripheral portion of a cylindrical main body. 2. A method for manufacturing a resin joint according to claim 1, wherein the resin joint is manufactured by injecting a molten resin into the cavity. 3. A joint made of FRP having a female thread on a cylindrical main body, wherein the female thread is formed by a male screw provided on a core rod for molding the cylindrical main body. Resin joints. 4. A method for impregnating a resin into a glass fiber bundle and using a core rod to draw and form the FRP tubular body according to claim 3, wherein the core rod is provided with a male screw and is rotationally extracted. A method for producing a resin joint, comprising: 5. A connecting member, wherein a male screw-equipped member is screwed and connected by the resin joint according to claim 1. 6. The connecting body according to claim 5, wherein the externally threaded member is a lock bolt.