JPH08105430A - Frp cylinder body and manufacture of it - Google Patents

Abstract

PURPOSE: To prevent breakage of reinforced fiber in a main body cylinder by biting teeth in a press fitting member so as to improve the strength of the main body cylinder in a faying part. CONSTITUTION: In an FRP cylinder body, the other member 2 is press fitted to an FRP main body cylinder 1 so as to be connected to it, and in the other member 2, biting teeth 3, which extend in the axial direction and are arranged in the circumference direction, are arranged on a faying face with the main body cylinder 1, while in each of tips 3a of the biting teeth 3, roundness having a radius of curvature of five times the diameter of the reinforced fiber in the main body cylinder 1 or more is provided, and/or a circumferential arrangement pitch for the biting teeth 3 is set to be 50 times as long as the diameter of the reinforced fiber diameter or more.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an FRP (fiber reinforced plastic) cylinder suitable for use in a propeller shaft (drive propulsion shaft) of an automobile and a method for manufacturing the same.

[0002]

2. Description of the Related Art Recently, FRP cylinders have been used in various industrial fields. For example, in recent years, there has been a strong demand for weight reduction of automobiles from the viewpoint of improving fuel efficiency and environmental protection.
RP has been studied and some have already adopted it. Such an FRP propeller shaft has a FRP main body cylinder and metal joints provided by joining to each end of the main body cylinder.

By the way, the propeller shaft of an automobile is
Since the torque generated by the engine is transmitted to the drive wheels as a torsional torque, a torsional strength of about 100 to 400 kgf · m is required. In addition, the dangerous number of rotation is 5,000 to 15,000 so that resonance does not occur at high speed rotation.
It is also required to be about 0 rpm. Therefore, in order to satisfy these basic requirements, the main body cylinder of the FRP propeller shaft has parameters such as the type and content of reinforcing fibers, the arrangement direction of the reinforcing fibers, the layer configuration, the outer diameter, the inner diameter, and the wall thickness. Is designed in consideration of.

For example, in selecting the arranging direction of the reinforcing fibers, the following is taken into consideration. That is, mainly regarding the torsional strength, it is most effective to arrange the reinforcing fibers at an angle of ± 45 ° with respect to the cylinder axis direction of the main body.
Mainly with respect to torsional buckling strength, ±
It is most effective to arrange at an angle of 80 to 90 °.
Regarding the critical rotation speed, the reinforcing fibers are arranged in the cylinder axis direction as much as possible to increase the bending elastic modulus in the cylinder axis direction so that a high bending resonance frequency can be obtained.

As described above, in the FRP main body cylinder,
Since there are the most effective arranging directions of the reinforcing fibers with respect to the basic requirements such as the torsional strength and the critical rotational speed, a layer structure in which the arranging directions suitable for these requirements are combined is adopted. Such an FRP main body tube is formed by a so-called filament winding method in which a resin-impregnated reinforcing fiber bundle is wound around a mandrel in a predetermined direction and cured and molded, and has the desired array of reinforcing fibers as described above. The layers are constructed. This reinforcing fiber is usually
It is in the form of continuous fibers that are aligned as a reinforcing fiber bundle.

A joint is joined to the end portion of the FRP main body cylinder thus formed by, for example, press fitting. In order to secure the joint strength of the joint, the outer diameter of the press-fitting portion of the joint is set to be slightly larger than the inner diameter of the main body tube end portion, and a so-called press-fitting margin is provided. Further, in order to further enhance the joining strength of the press-fitting portion, it is effective to provide the joint surface of the joint press-fitting portion with the main body cylinder with a plurality of cutting teeth extending in the cylinder axial direction of the main body cylinder and arranged in the circumferential direction. It has been known.

[0007]

However, when the joint is provided with the cutting teeth as described above, when the fitting is press-fitted, the cutting teeth bite into the inner peripheral surface of the FRP main body cylinder. However, at that time, the reinforcing fibers arranged on the inner peripheral surface of the main body cylinder may be cut. In particular, from the viewpoint of improving the joint strength, the tip of the incision may be sharpened,
If the arrangement pitch of the cutting teeth arranged in the circumferential direction is extremely narrowed, when the cutting teeth bite into the inner peripheral surface of the main body cylinder, the reinforcing fibers are cut by the sharp tips of the cutting teeth, or the reinforcing fibers are formed between the adjacent cutting teeth. A situation in which excessive tensile tension is applied to cut the reinforcing fiber is likely to occur.

When the reinforcing fiber is cut, the strength of the main body cylinder at the joint portion with the joint partly decreases, and the target strength performance is not exhibited at that portion, so the cutting of the reinforcing fiber is prevented as much as possible. There must be.

An object of the present invention is to cut a reinforcing fiber at the time of press-fitting by a cutting tooth in a FRP cylinder body such as a FRP propeller shaft, in which another member having a cutting tooth is press-fitted and joined to a FRP main body cylinder. To improve the strength of the main body cylinder at the joint.

[0010]

According to the FRP cylinder body of the present invention for this purpose, another member is press-fitted and joined to the FRP main body cylinder, and the other member extends in the axial direction at the joint surface with the main body cylinder. In addition, the FR is provided with cutting teeth arranged in the circumferential direction.
In the P tubular body, the tip of the cutting tooth is rounded with a radius of curvature of 5 times or more the diameter of the reinforcing fiber used in the main body tubular body.

This structure is particularly effective when the reinforcing fibers are arranged in the axial direction of the main body cylinder on the inner peripheral surface of the main body cylinder facing the joining surface. Here, the "axial direction of the main body cylinder" means 0 to ± 4 with respect to the cylinder axial direction of the main body cylinder.
It is in the range of 5 °.

The FRP cylindrical body according to the present invention is FR
In the FRP cylinder body, another member is press-fitted and joined to the P-made main body cylinder, and the joint surface of the other member with the main body cylinder is provided with cutting teeth extending in the axial direction and arranged in the circumferential direction. The arrangement pitch of the cutting teeth in the circumferential direction of the joint surface is 50 times the diameter of the reinforcing fiber used in the main body cylinder.
It is more than doubled.

This structure is particularly effective when the reinforcing fibers are arranged in the inner peripheral surface of the main body cylinder facing the joining surface in the circumferential direction of the main body cylinder. Here, the “circumferential direction of the main body cylinder” is ± 45 to the cylinder axis direction of the main body cylinder.
It is in the range of 90 °.

Further, it is also possible to adopt a structure in which the above two structures are combined. That is, the FRP cylinder according to the present invention is
In the FRP cylinder body, another member is press-fitted and joined to the FRP main body cylinder, and the joint surface of the other member with the main body cylinder is provided with cutting teeth extending in the axial direction and arranged in the circumferential direction.
A roundness having a curvature radius of 5 times or more the diameter of the reinforcing fiber used in the main body cylinder is attached to the tip of the cutting tooth, and the cutting tooth in the circumferential direction of the joint surface. The arrangement pitch is 50 times or more the diameter of the reinforcing fibers.

The FRP cylindrical body according to the present invention as described above is
It is the most suitable for RP propeller shafts.
When applied to a propeller shaft, the main body cylinder corresponds to a propeller shaft shaft, and the other member corresponds to a joint. However, the present invention is not limited to the propeller shaft, but can be applied to other FRP cylinders to which other members having cut teeth are press-fitted and joined, such as FRP roll members and piping members, FRP trusses, and the like.

The above FRP cylinder is manufactured, for example, as follows. That is, the manufacturing method of the FRP cylinder according to the present invention, when manufacturing the FRP cylinder by press-fitting and joining other members to the FRP main body cylinder, the joint surface with the main body cylinder extends in the axial direction, and The tip of the teeth arranged in the circumferential direction has a radius of curvature of 5 times or more the diameter of the reinforcing fiber used in the main body cylinder, and the arrangement pitch in the circumferential direction of the joint surface is used for the main body cylinder. The method is characterized in that another member having a cutting tooth having a diameter of 50 times or more the diameter of the reinforcing fiber is press-fitted and joined so that the tooth tip of the cutting tooth bites into the inner peripheral surface of the main body cylinder.

[0017]

In the FRP cylinder as described above, the tip of the cutting tooth is rounded with a radius of curvature that is at least five times as large as that of the reinforcing fiber used in the main body cylinder. The stress acting on the inner peripheral surface of the main body cylinder is more widely dispersed without being concentrated at one point, and the cutting of the reinforcing fiber by a sharp tooth tip is reduced. Therefore, even at the tip of the tooth bite, the target strength characteristics are ensured by the arrangement of the reinforcing fibers made of continuous fibers.

When the reinforcing fibers of the main body cylinder are arranged in the axial direction of the main body cylinder on the inner peripheral surface of the main body cylinder facing the joining surface, that is, in the direction substantially parallel to the extending direction of the cutting teeth of the other member. When the other member is press-fitted, when the other member is press-fitted, the cutting tooth having the rounded tip as described above pushes the reinforcing fibers existing in the surface layer portion of the inner peripheral surface of the main body cylinder to push it away to both sides of the tip. Since it cuts into the inner peripheral surface of the cylinder, the cutting of the reinforcing fiber can be prevented more effectively.

Further, by setting the pitch of the cutting teeth arranged in the circumferential direction to be 50 times or more the diameter of the reinforcing fiber,
Even if tension is applied to the reinforcing fiber between the adjacent tooth tips, the distance between the adjacent tooth tips is long, so the degree of freedom of the reinforcing fiber increases during this period, and the situation in which the reinforcing fiber is cut is properly prevented. To be done. Particularly, when the reinforcing fibers are arranged in the circumferential direction of the main body cylinder on the inner peripheral surface of the main body cylinder facing the joining surface of the other member to be press-fitted, that is, with respect to the cutting tooth extending direction of the other member. When the fibers are arranged in a direction substantially orthogonal to each other, the above tension is likely to be applied, but the structure according to the present invention effectively prevents the reinforcing fibers from being cut.

Further, by rounding the tips of the cutting teeth at least 5 times the diameter of the reinforcing fibers, and setting the pitch of the cutting teeth arranged in the circumferential direction at least 50 times the diameter of the reinforcing fibers, Both of the above effects will be obtained,
For example, even when the inner peripheral surface of the main body tube has a laminated structure of a plurality of layers in which the arranging directions of the reinforcing fibers are different, the cutting of the reinforcing fibers can be efficiently and effectively prevented.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the FRP cylinder of the present invention will be described below together with the manufacturing method thereof with reference to the drawings. 1 to 3 are FRs according to a first embodiment of the present invention.
2 shows a P cylinder, and shows a case where the present invention is applied to a FRP propeller shaft. In FIG. 1, 1 is F
1 shows a shaft for a propeller shaft as an RP main body cylinder, wherein the main body cylinder 1 is a high strength, high elastic modulus reinforcing fiber such as carbon fiber, glass fiber, polyaramid fiber, etc., which is an epoxy resin, unsaturated polyester resin, phenol resin, It is made by reinforcing a thermosetting resin such as a vinyl ester resin or a polyimide resin, or a thermoplastic resin such as a polyaramid resin, a polycarbonate resin or a polyetherimide resin. A metal joint 2 as another member is press-fitted and joined to one end and the other end of the main body cylinder 1. This propeller shaft is symmetrical when viewed from the center in the lengthwise direction, and the figure shows only one end side.

The press-fitting joint surface 2a of the joint 2 to the main body cylinder 1 is provided with cutting teeth 3 extending in the cylinder axis direction of the main body cylinder 1 and arranged in a large number in the circumferential direction. The outer diameter of the joint surface 2a, or more accurately, the outer diameter of the top of the cutting tooth 3 is set to be slightly larger than the inner diameter of the main body cylinder 1, and the joint 2 has a predetermined press fitting allowance within the end portion of the main body cylinder 1. Has been pressed into. At the time of this press-fitting, the notch teeth 3 bite into the inner peripheral surface 1a of the main body cylinder 1 from the tip tooth tip side thereof.

The tip 3a of the cutting tooth 3 is provided with a roundness 3a as shown in FIG. The radius of curvature of the roundness 3a is the same as that of the reinforcing fiber 4 (see FIG.
The diameter is set to 5 times or more. The radius of curvature of the roundness 3a is not particularly limited as long as it is 5 times or more the diameter of the reinforcing fiber, but when considering the ease of penetration of tension into the inner peripheral surface 1a, it is 50 times or less the diameter of the reinforcing fiber. It is preferable to set to.

The reinforcing fiber 4 used in the main body tube 1 is
As shown in FIG. 3, it is arranged in the axial direction of the main body cylinder 1 on the inner peripheral surface of the main body cylinder 1 facing the joining surface 2a. That is, they are arranged in a direction within a range of 0 to ± 45 ° with respect to the cylinder axis direction of the main body cylinder 1.

The main body tube 1 as described above can be formed by, for example, the following filament winding method. A resin-impregnated reinforcing fiber bundle is wound around a mandrel in a predetermined array direction while moving in the axial direction of the mandrel, and reciprocated a predetermined number of times to form a laminated structure, and the resin is cured or fixed and then molded. Remove the main body tube from the mandrel. Post-processing if necessary,
Obtain the desired body tube.

At the time of press-fitting, in which the joint 2 having the cutting teeth 3 as described above is press-fitted and joined to the end of the obtained main body cylinder 1,
By rounding the tip 3a of the cutting tooth 3, cutting of the reinforcing fiber 4 is prevented as follows.

That is, as shown in FIG.
Cuts into the inner peripheral surface 1a of the main body cylinder 1. However, since the tooth tip 3a of the incision tooth 3 is provided with a roundness having a large radius of curvature of 5 times or more the diameter of the reinforcing fiber 4, the tooth tip 3a is When biting, the reinforcing fibers 4 located at the positions where they interfere with the tooth tips 3a are pushed out mainly on both sides of the tooth tips 3a by the roundness. As a result, the tooth tip 3a does not cut the reinforcing fiber, and the tooth tip 3a smoothly bites into the inner peripheral surface 1a of the main body cylinder. Since the reinforcing fibers 4 are not cut and the reinforcing fibers 4 can surely maintain the form of continuous fibers even in the inner peripheral surface 1a portion, the strength of the main body cylinder 1 in this portion is ensured to the target characteristic. Therefore, the joint strength with the joint 2 is also kept high.

FIG. 4 shows an FRP according to the second embodiment of the present invention.
The longitudinal section of the junction part of a main part cylinder and a joint of a propeller shaft made from is shown. In this embodiment, the circumferential arrangement pitch P of the cutting teeth 13 provided on the joint surface 12a of the joint 12 is set to be 50 times or more the diameter of the reinforcing fibers 14 used in the main body cylinder 11. In this structure, the arranging direction of the reinforcing fibers 14 faces the joint surface 12a and the main body tube 11
It is particularly effective when it is set in the inner peripheral surface in the circumferential direction of the main body cylinder 11. That is, it is particularly effective when the direction is a direction substantially orthogonal to the cylinder axis direction of the main body cylinder 11 (direction within a range of ± 45 to ± 90 °). The upper limit of the pitch P is not particularly limited, but if it is too large, the number of the cutting teeth 13 decreases and the effect of improving the bonding strength due to the provision of the cutting teeth 13 is diminished. It is preferable to keep. Such cutting teeth 13 are formed by press-fitting the inner peripheral surface 1 of the main body cylinder 11.
It is cutting into 1a.

In the present embodiment, in addition to the above-mentioned structure, the tooth tops 13 of the cutting teeth 13 are the same as in the first embodiment described above.
The a is rounded with a radius of curvature of 5 times the diameter of the reinforcing fiber 14 or more.

In such a structure, first, the arrangement pitch P of the cutting teeth 13 is set to be 50 times or more as large as the diameter of the reinforcing fibers 14, so that the joints 12 are adjacent to each other even after press fitting or after press fitting. Cutting tooth 13
Even when the reinforcing fiber 14 is tensioned between them and a tension is applied thereto, since the degree of freedom of the reinforcing fiber 14 between the cutting teeth 13 is large, the cutting of the reinforcing fiber 14 is appropriately prevented.

Further, by setting the roundness of the tip of the tooth tip 13a of the cutting tooth 13 to be 5 times or more the diameter of the reinforcing fiber, it is possible to avoid the situation where the reinforcing fiber 14 is cut by a sharp tooth tip and the reinforcing fiber is cut. 14 can be bent appropriately without being cut like pushing from the tip position.

Therefore, cutting of the reinforcing fiber 14 can be reliably prevented, and the strength of the main body tube 11 at the joint with the joint 12 and the joint strength with the joint 12 can be secured high.

[0033]

As described above, according to the FRP cylinder and the method of manufacturing the same of the present invention, it is possible to effectively cut the reinforcing fiber in the FRP main body cylinder at the joint portion with the other member having the cutting teeth. Therefore, high strength of the main body cylinder and high joint strength with the joint can be obtained at this portion.

[Brief description of drawings]

FIG. 1 is a partial vertical sectional view of an FRP propeller shaft according to a first embodiment of the present invention.

FIG. 2 is an enlarged partial cross-sectional view of the propeller shaft of FIG.

FIG. 3 is an enlarged partial cross-sectional view of the portion shown in FIG.

FIG. 4 is a partial cross-sectional view of an FRP propeller shaft according to a second embodiment of the present invention.

[Explanation of symbols]

 1, 11 FRP main body cylinder 1a, 11a Main body cylinder inner peripheral surface 2, 12 Joint (other member) 2a, 12a Joint joint surface 3, 13 Cutting tooth 3a, 13a Tip 4,4 Reinforcing fiber

Claims (7)

[Claims] 1. An FR in which another member is press-fitted and joined to a main body cylinder made of FRP, and notch teeth extending in the axial direction and arranged in the circumferential direction are provided on a joint surface of the other member with the main body cylinder.
In the P tubular body, the tip of the incision tooth is rounded with a radius of curvature that is 5 times or more the diameter of the reinforcing fiber used in the main body barrel. 2. The FRP cylinder according to claim 1, wherein the reinforcing fibers are arranged in an axial direction of the main body cylinder on an inner peripheral surface of the main body cylinder facing the joining surface. 3. An FR, in which another member is press-fitted and joined to an FRP main body cylinder, and cutting teeth that extend in the axial direction and are arranged in the circumferential direction are provided on a joint surface of the other member with the main body cylinder.
In the P tubular body, the arrangement pitch of the cutting teeth in the circumferential direction of the joining surface is 50 times or more the diameter of the reinforcing fiber used in the main body barrel.
P cylinder. 4. The FRP cylinder according to claim 3, wherein the reinforcing fibers are arranged in a circumferential direction of the main body cylinder on an inner peripheral surface of the main body cylinder facing the joining surface. 5. An FR in which another member is press-fitted and joined to a main body cylinder made of FRP, and notch teeth extending in the axial direction and arranged in the circumferential direction are provided on a joint surface of the other member with the main body cylinder.
In the P tubular body, the tips of the cutting teeth are rounded with a radius of curvature of 5 times or more the diameter of the reinforcing fibers used in the main body cylinder, and the cutting teeth have
The FRP cylinder body, wherein the arrangement pitch in the circumferential direction of the joint surface is 50 times or more the diameter of the reinforcing fiber. 6. The main body cylinder is a shaft for a propeller shaft, and the other member is a joint.
The FRP cylinder according to any one of 1. 7. When manufacturing another FRP cylinder by press-fitting and joining another member to the main body cylinder made of FRP, tooth tips which extend in the axial direction and are arranged in the circumferential direction on the joint surface with the main body cylinder. Has a roundness with a radius of curvature of 5 times or more the diameter of the reinforcing fiber used in the body tube, and the arrangement pitch in the circumferential direction of the joining surface is 50 times the diameter of the reinforcing fiber used in the body tube. A method for manufacturing an FRP tubular body, which comprises press-fitting and joining another member having double or more cutting teeth so that the tips of the cutting teeth bite into the inner peripheral surface of the main body cylinder.