JPS62267133A - Fiber-reinforced tubular member and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention generally relates to fiber-reinforced or reinforced tubular members such as vehicle drive shafts, and more specifically relates to graphite-reinforced tubular members. aluminum drive shafts and methods of manufacturing such drive shafts.

(1) Background Art Over the past decade, there has been a continuous effort in the industry to reduce the weight of vehicles to improve fuel economy. In addition to downsizing and redesigning vehicles, much attention is also being paid to making various vehicle components from lighter materials.For example, in the area of drive shafts, traditional steel drive shafts are being replaced by It has been proposed to replace it with a more lightweight aluminum tube, but depending on the length of the drive shaft and the maximum number of turns rotating the drive shaft, vibration problems can occur.

Tubular steel drive shafts or tubular aluminum drive shafts are typically sufficient to transmit the necessary torsional forces, but once the shaft reaches vehicle speed, which is typically referred to as the critical speed, the shaft It tends to have a whip or mechanical resonance. Therefore, multiple sectioning of the shaft is typically used to overcome the critical speed limitations for a single long drive shaft. In these cases, adjacent individual driveshaft sections are connected in rotation by a universal joint, which in turn is supported by a bearing mounting arrangement mounted on the vehicle frame.

To accommodate long drive shafts in a condition where universal joints and bearing mounting devices can be removed, the metal tube is reinforced with a fiber-reinforced sleeve section, which increases the length of the shaft without substantially increasing the weight. It has been proposed to increase the axial stiffness. For example, U.S. Pat. It is covered with every other layer of impregnated fiber reinforced sheets. This reinforced sheet uses graphite fibers at an angle of ±5° with respect to the longitudinal axis of the tube.
It consists of continuous unidirectional graphite fiber layers arranged at angles between 1208 and 1208. Another approach to reinforcing tubular metal drive shafts is disclosed in US Pat. No. 4,272,971, which discloses a drive shaft, in which a fiber reinforcement layer is applied to the inner surface of an aluminum tube.

Although the fiber-reinforced drive shafts described above have satisfactory operational performance, these drive shafts have proven difficult and expensive to produce on a mass production basis.

←→ SUMMARY OF THE INVENTION This invention relates to a unique fiber-reinforced or fiber-reinforced aluminum drive shaft and a unique method of manufacturing such a drive shaft on a production basis.

The drive of the invention includes a cylindrical metal tube having a longitudinal axis, typically constructed of aluminum in the preferred embodiment of the invention. A standoff layer of cloth material surrounds the aluminum tube and is adhered or adhered to the exterior surface of the aluminum tube. A reinforcing fiber layer also surrounds the aluminum tube and is bonded to the outer surface of the isolation layer. According to this invention,
The reinforcing fiber layer includes a plurality of individual reinforcing graphite fibers oriented parallel to the longitudinal axis of the aluminum tube and positioned uniformly around the circumference of the aluminum tube.

In the prior art described above, the graphite fibers were specifically placed non-parallel to the longitudinal axis. The drive shaft further includes a covering layer of fibrous material surrounding the tube and bonded to the outer surface of the reinforcing fibrous layer.

This invention includes a unique approach to production on a fiber reinforced drive shaft production base. In the method according to the invention, a plurality of cylindrical metal tubes, each having a longitudinal axis, are joined together at their ends by a plurality of connecting plastic plugs to form a series of longitudinally extending metal tubes. splice into. This series of metal tubes is fed along a longitudinal path through equipment that applies individual layers of composite fiber sleeves to the metal tubes.

First, a separating layer of cloth material is applied around the outer surface of the metal tube. A plurality of individual reinforcing fibers are then applied around the circumference of the metal tube K such that the reinforcing fibers are parallel to the longitudinal axis of the metal tube. A covering layer of fibrous material is then applied around the outer surface of the reinforcing fibrous layer.

While the individual layers are being applied to the metal tube, a vinyl ester liquid resin material is applied to saturate the individual layers, and the drive shaft with the applied saturation layer is then fed through a heated forming die where The liquid resin is cured to firmly adhere each layer to a series of metal tubes. As the series of metal tubes with hardened composite sleeves exit the manufacturing equipment, they are cut at each plug member to form a plurality of individual fiber-reinforced drive shafts. If, for example, a yoke section or a splined shaft has to be welded to the end of the drive shaft, the ends of the composite sleeve can be removed during the welding operation by stripping selected end portions of the composite reinforcing layer from the drive shaft. It has been found that it is desirable to prevent heat damage to.

The invention also relates to an alternative method of manufacturing a drive shaft.

B)) EXAMPLES The present invention will be described in detail below based on examples thereof with reference to the accompanying drawings.

FIG. 1 shows a drive shaft (10) using a composite tubular member embodying the features of the invention. This drive shaft (10'
) Vi with an outer composite fiber-reinforced or reinforcing sleeve (12), which sleeve (12) comprises a cylindrical metal tube (14)
Surround the outside of and attach it to this.

First and second connecting members (shown as yoke portions)
16) (ts) connects the drive shaft to the driving member and the driven member (
A metal tube (14
) to the opposite ends. Although these coupling members are shown as yoke sections for coupling to an associated universal joint arrangement (not shown), it will be appreciated that other types of coupling members may also be used, such as splined shafts. It is.

The connecting members (16), (18) Fi are typically fixed to the ends of the metal tube (14) by welding. In order to prevent damage to the composite sleeve (12) when installing the connecting member,
The end of the reinforcing sleeve (12) is spaced inwardly from the end of the metal tube (14) to expose the metal ends (20, 22). As shown in the preferred manufacturing method described below, the reinforcing sleeve (12) is first formed over the entire length of the metal tube (14) and subsequently sawed from the ends (20) (22). Remove by cutting circumferentially and peeling off. In another manufacturing method, a reinforced sleeve (12
) is formed in such a way that the first ends (20) (22) are not covered thereby.

FIG. 2 shows a cross section through the metal tube (14) and a preferred example of the composite reinforcing sleeve (12). This metal tube (14) is typically a conventionally made cylindrical aluminum tube. The length, diameter, and wall thickness of the aluminum tube are determined by the particular aluminum alloy from which the aluminum tube is formed. and, depending on the specific power transmission requirements of the drive shaft,
It can be changed each time it is used. In each case, a composite reinforcing sleeve (1
It has been found that the use of 2) can significantly increase the axial stiffness of the aluminum tube and substantially reduce the tube weight compared to a tubular aluminum drive shaft without a reinforcing sleeve.

The composite reinforced sleeve (12) basically consists of three sections: an isolation layer (32), a fiber reinforcement layer (34), and a cover layer (36). In the preferred manufacturing process, the individual layers of the sleeve (12) are bonded to each other and to the tube by vinyl ester, as described below.

The isolation layer (32) has individual layers (32a) (32b)
(32c). The first isolation layer (32a) comprises a plurality of longitudinally extending string materials equally spaced around the circumference of the metal tube.
It consists of a thread (thread). Although this layer is not essential to the functioning of the invention, it is important to note that this contact between the metal tube (14) and the saw blade (not shown) when stripping off the end of the aforementioned reinforcing sleeve (12) will be explained later. Use as a visual display to avoid. In the preferred embodiment of the drive shaft, the isolation layer (32a) is comprised of eight longitudinally extending polyester strings equally spaced around the circumference of the metal tube.

The second isolation layer (32b) consists of individual strips of thin screen-like cloth material with overlapping transverse binding extending in the longitudinal direction and completely surrounding the metal tube.

This layer includes a fiber-reinforced layer (34), typically graphite, on the aluminum tube, since this direct contact with graphite has been found to result in undesirable galvanic corrosion.
14).

The exact width of the individual strips, together with the outer diameter of the metal tube,
Sized by the number of strips used. Although the number of strips of fabric material used to surround the metal tube can vary from use to case, the preferred embodiment utilizes four individual strips of fabric material.

The third isolation layer (32e) is similar to the first isolation layer (32a) and is made of a plurality of threads of polyester strings arranged longitudinally evenly spaced around the circumference of the metal tube. configured. The preferred embodiment uses eight threads. This is also not an essential layer, but is used to form and hold a strip of fabric material in place on the metal tube (14). The fabric isolation layer (32a) (32c) is shown in Figure 2 in such a way that the fabric isolation layer (32b) is spaced from both the metal tube (14) and the fiber reinforced layer (34) As an indication,
Between the isolation layer (32b) and the metal tube (14), the isolation layer (
It will be seen that there is actually contact between 32b) and the fiber reinforced layer (34) in the region between the spaced longitudinally extending filaments.

The fiber reinforcement layer (34) typically comprises graphite and is comprised of a plurality of individual independent reinforcing fiber strands or tows.
), and these strands are preferably placed according to the invention parallel to the longitudinal axis of the metal tube and uniformly located around the isolation layer (32). Each tow is comprised of a predetermined number of individual graphite fibers arranged longitudinally. The exact number of graphite tows to be used will depend on the number of individual fibers placed within each tow and the total amount of reinforcement that will be nitrided. One preferred embodiment uses 115 vertically arranged tows of graphite fibers, each tow having a diameter of 36,000
It is composed of individual graphite fibers.

The covering layer (36) or protective layer includes individual layers (36a) (3
6b) (36c) to act as a device to hold the longitudinally oriented graphite strands of layer (34) adjacent to metal tube (14). The first covering layer (36a) consists of a circumferential sheath of wide strands of fibers. The number of circumferential sheaths for a given length of tube depends on the amount of graphite applied to the tube, as well as the number of individual glass fibers included in each strand. In the preferred embodiment, each strand is comprised of 1,800 fiberglass fibers wrapped around the tube to obtain 20 turns per inch of length.

The second covering layer (36b) is another circumferential covering similar to that of the first covering layer (36a), but
and a similar type of polyester fiber to that used for the third isolation layer (32a) (32c). It should be noted that although layers (36a) and (36b) are described here as overlapping layers, they do not form visibly separate layers, and the reason for this is that there is one overlapping layer. The strands typically fall between the strands of the other sheaths, so that layers (40) and (42) visually appear as a single layer.

The third coating layer (36c) is the outermost layer of the sleeve (12).
) is similarly applied and identical in material properties to that of the isolation layer (32b), so as to provide an outer fabric covering that produces a smooth outer surface over the drive shaft.

FIG. 3 schematically shows an apparatus for forming composite tubular members of the type shown in FIG. 2 on a continuous basis. As shown in FIG. 3, a plug member, typically made of plastic material, has a plurality of metal tubes (14a, 14b, 14d) connected end to end by a plurality of plug members (42). (4
2) is shown as a double knot and has a centrally located protruding annular seven-run section (44) with an outer diameter greater than the outer diameter of the metal tube. As will be explained below, the protruding flange (44) serves as a visual reference point for determining the specific point where the metal tube must be sawed off after each layer of the composite sleeve has been applied to the metal tube and cured. Forms an annular lifting part.

The apparatus (40), which will be described in detail below, is used to apply the various materials required to form a composite fiber sleeve on the aluminum tube. The apparatus (4o) also includes a pair of pulling rollers (46) for pulling the series of longitudinally extending tubes at a predetermined speed along a longitudinally extending path through the apparatus.
Have (4B).

As shown in FIG. 3, at a first point (50) a first isolation layer (32) of longitudinally extending and circumferentially spaced fibers is formed.
Perform a). Fiber strip I from multiple rolls (52)
A guiding device (54) which may be a pulley or the like
and through the dispensing device (56) to its proper location on the tube (14). Although four rolls are shown, the preferred embodiment of the invention uses eight rolls. Also, the winding frame used is shown here as a roll or winding frame with Qi A attached, but the winding frame should preferably be of the center feed type, so that the last winding is on the outside and the additional roll interferes with the process. It is better to make it possible to connect without any problem.

A second isolation layer (32b) consisting of a strip of fabric material is then applied at a second point (58). As shown, the layers (
32b) is applied in four segments. 2nd point (5
8), the material of the second tube (32b) is rolled (60)
Apply from (62). Although not shown, roll (62) is preferably placed along a line perpendicular to the line along which roll (60) is placed.

Each strip is matched to the shape of the tube (14) by a conical preformer (64).

Next, at a third point (66) a third
A fabric layer (32c) is applied around the tube (14).
32b). As at the first point, the string coming from the rolls is routed through a guiding device (70) and an applicator device (72) to a position around the tube (14).

At the fourth point (74) approximately half of the fiber reinforcement layer (34) is applied. The set of rolls (76) is shown six in number for simplicity, but in reality it will amount to about half of the total number of graphite tows to be applied. The tow fed from the roll (76) passes through individual holes in the forming ring (78) to match the shape of the metal tube (14). The resin mixture is then transferred from the tank (82) to the pipe (80) at a fifth point (80)K.
4) to the dispensing end (86) from which it coats the first half of the fiber reinforcement layer (34) and the underlying isolation layer (32).

The resin mixture in tank (82) is preferably a vinyl ester resin mixture of the type available under the tradename Perakane. A suitable resin admixture is available from the Dow Chemical Company, Joliet, Illinois, as part number 411-35. Additionally, any conventional resin admixture can be used, but it must be selected among those that remain flexible after curing. Although not shown, the catalyst or curing agent can be mixed with the resin mixture shortly before applying the mixture to the partially formed sleeve.

At the sixth point (88), the desired number of remaining graphite tows is removed by 1
from the set of rolls (90) through the forming ring (92) into alignment with the tube (14) and at a seventh point (94) through the tube (96) and dispensing end (98). Tank (8
Coat again with the resin mixture from 2).

At the eighth point (ioo) and the ninth point (102), a spinning head (
104). Spinning head like this (104)
You may have one or more layers (36a) (36b
This does not mean that one or more single rolls may be used to apply the same effect. As mentioned above, the head (104)
The roll (106) comprises a first covering layer (36a) of fiberglass material and a second covering layer (10B) of soil (
36b) with polyester strinda material.

As mentioned above, the covering layers (36a) (36b) are circumferential coverings, which in this example are applied at a rate of about 20 Vi1 inches. At the tenth point (110), the resin mixture from the tank (82) is applied through the tube (112) and the dispensing end (114).

A final or third coating layer (36c) is then applied at the eleventh point (116). a set of rolls (118) having the same fabric material as roll (60);
This material is conformed to the shape of the tube (14) by means of a conical preformer (120). 1 set of rolls (122)
The roll (62) is provided with the same fabric material as was carried on the roll (62), which is forced to conform to the shape of the tube (14) by means of the conical inlet (124) of the heated forming die (126). As in the case of rolls (60) and (62), rolls (
118) (122) should be placed along mutually perpendicular lines as much as possible. The forming die (126) not only forms the surface of the continuous drive assembly shaft, but also provides adequate heat for rapid curing of the resin mixture as the series of drive shafts is pulled through the device (40). It is something.

A continuous chain of composite tubular members (10) is then
The protruding flange (44) can be cut away to form exposed barbed ends (20) (22), which can then be stripped off in the manner described above, to which suitable connections can be attached by conventional welding techniques. can. The composite tubular member made by the method shown in FIG. 3 is shown in FIG. 4 before the connecting member is attached.

It will be appreciated that other methods embodying the key features of this invention may be used to make the fiber-reinforced aluminum driveshaft. For example, in the method illustrated diagrammatically in FIG.
4) is obtained by having an inner diameter slightly larger than the outer diameter.

As shown in FIG. 5, the reinforcing sleeve (130) is slid into position over the metal tube (132) with a layer of glue (134) applied thereto.

Glue (134) may be replaced with any type of glue or binder. One such structural adhesive that can be used here is Metal! Metalbond
1133 and is an elastomer modified epoxy material sold by the Narmco Division of Celanese Company, New York, New York. Such adhesives are applied by brush or spray.

FIG. 6 diagrammatically shows yet another method of manufacturing a composite tubular member according to the invention, in which a fiber-reinforced sleeve (140) saturated with uncured resin and of suitable length is used.
is slid over the metal tube (142) and then cured to bond the sleeve (140) to the metal tube (142). If desired, a suitable structural adhesive can be used to aid in bonding the sleeve to the tube. In Figure 6,
A sleeve (140) is formed over the mandrel (148) and extends over the tube (
tank (150) through the dispensing end (154) and the dispensing end (154).
), or alternatively by any other convenient device, such as a brush or spray. As previously mentioned, a reinforced sleeve (140)
is comprised of three layers: an inner layer of isolating material supplied by rolls (156), an intermediate layer of longitudinally extending reinforcing fibers supplied by rolls (15B), and a roll (160).
It has an outer layer consisting of a coating material supplied with.

As shown in FIG. 6, the metal tube (142) is supplied, the sleeve (140) is separated from the mandrel (148), and the metal tube (14
2) Remove this sleeve (140) by sliding it towards (a)
is placed on each metal tube, where the sleeve is positioned by applying a circumferential force in a suitable manner, such as by pulling a forming die over it. The sleeve (140) is then cured in place on the metal tube (142) over time without heating, or alternatively by heating in any suitable manner.

The exact embodiment of the reinforcing sleeve used in the method shown in FIGS. 5 and 6 may differ from the structure shown in FIG. 2 and obtained in the method of FIG. For example, FIG. 2 provides a visual indication of stripping the sleeve end in the method of FIG.
The third isolation layer (32aX32c) is not necessary in the method of FIGS. 5 and 6 because the reinforcing sleeve is formed to a predetermined length before being applied to the metal tube. In case of becoming a
A second isolating layer (32b) is also formed between the graphite and aluminum by itself the glue used to hold the previously formed hardened or unhardened reinforcing sleeve to the metal tube. This is not necessary as it creates a suitable isolation layer. The outermost covering layer (36c) in Fig. 2 used to form a smooth outer surface is not absolutely necessary, but the covering layer (36c) used to keep the primary reinforcing fiber layer (34) in its normal position. 36a) (36b) The same applies to the use of two different materials, shown as (36b).

Although the present invention has been described in detail based on the embodiments above, these embodiments can be modified in various ways, such as rearranging the order of layers or increasing or decreasing the number of layers, without departing from the spirit of the invention. Needless to say.

[Brief explanation of the drawing]

Fig. 1 is a side view of the fiber-reinforced composite tubular member of the present invention when used as a drive shaft, and Fig. 2 is a straight line 2-2 in Fig. 1 showing each layer constituting a preferred embodiment of the fiber-reinforced composite sleeve. FIG. 3 is a schematic diagram illustrating one method of manufacturing fiber-reinforced composite tubular members of the present invention on a continuous basis, in which the fiber-composite sleeves are temporarily strung together longitudinally. FIG. 4 is a side view of a composite fiber-reinforced tubular member obtained by the method shown in FIG. 3; FIG. is a schematic diagram showing another method of assembling the drive shaft,
In this case, a preformed and hardened fiber composite sleeve is shown sliding over the assembled metal tubes and secured to the tubes; FIG. 6 is a schematic diagram showing a further embodiment of the method of the invention. In this case, a previously formed, uncured, resin-saturated fiber reinforced sleeve is shown slid over a metal tube member and then cured thereon. DESCRIPTION OF SYMBOLS 10... Drive shaft, 12... Outer composite fiber reinforced sleeve, 14... Cylindrical metal tube, 16, 18... Connecting member, 20, 22... Metal end of 14, 32... Isolation layer, 34... Fiber reinforced layer, 36... Covering layer, protective layer, 40... Composite tubular member manufacturing device, 42... (metal tube connection) plug member, 44... Franz of 42 Department, 46
．． 48...Tension roller, 50.58.66, 74.
80.88°94, 100.102.110.116・
...Point, 52.68...Roll, 54.70...
Guide device, 56.72...Alms device, 60162+
1181122 =-0-Role, 64.120... Conical preformer -176, 90... Roll, 78
, 92... Forming ring, 82... Tank, 86.9
8.114...Dispensing end, 84.96.112...Tube, 104...Spinning bed, 106.108...Roll, 124...Conical inlet, 126...Forming die, 130...Sleeve, 132...Metal tube, 134
... Glue 140 ... Sleeve, 142 ... Metal tube, 148 ... Mandrel 150 ... Tank, 152 ...
・Pipe, 154...Dispensing end, 156°158.160・
··roll.

Claims (25)

[Claims] (1) (a) a cylindrical metal tube having a vertical axis; (b) an isolation layer surrounding the metal tube and bonded to the outer surface of the metal tube; (c) surrounding the metal tube and bonding the (d) a reinforcing fiber layer surrounding the metal tube and comprising a plurality of individual independent reinforcing fibers adhered to an outer surface of the isolation layer and positioned evenly around the periphery of the metal tube; a fiber-reinforced tubular member having a covering layer adhered to the outer surface of the layer. (2) The fiber-reinforced tubular member according to claim (1), wherein the reinforcing fiber layer is parallel to the longitudinal axis. (3) (a) a cylindrical metal tube having a longitudinal axis; (b) an isolation layer made of a cloth material surrounding the metal tube and adhered to the outer surface of the metal tube; (d) a reinforcing fiber layer comprising a plurality of individual reinforcing fibers surrounding and adhered to the outer surface of the isolation layer, parallel to the longitudinal axis and equally positioned around the periphery of the metal tube; A fiber-reinforced tubular member comprising a covering layer made of a fiber material surrounding the metal tube and bonded to an outer surface of the reinforcing fiber layer. (4) the isolation layer is provided with a plurality of longitudinally extending strips of fabric material positioned around the periphery of the metal tube, each adjacent strip of the strips being provided with the metal A fiber-reinforced tubular member according to claim 3, further comprising overlapping lateral edges such that the outer surface of the tube is completely surrounded by these strips. (5) a first isolation layer comprising a plurality of longitudinally extending and circumferentially spaced string members adhered to the outer surface of the metal tube; a second isolating layer of fabric material surrounding said second layer of material, said second layer comprising longitudinally extending and circumferentially spaced string members;
A fiber-reinforced tubular member according to claim 3, further comprising a third isolation layer adhered to the outer surface of the isolation layer. (6) A fiber-reinforced tubular member according to claim (3), wherein the covering layer includes a glass fiber string material wrapped circumferentially around the metal tube. (7) The covering layer includes a first covering layer made of a glass fiber material and surrounding the reinforcing fiber layer in the circumferential direction and bonded to the reinforcing fiber layer, and a string member, and the first covering layer is made of a string member. a second covering layer circumferentially surrounding the covering layer and adhered to the first covering layer; and a third covering layer made of a cloth material, adhered to and surrounding the second covering material. The fiber-reinforced tubular member according to claim (3), further comprising a coating layer. (8) The fiber-reinforced tubular member according to claim (3), wherein the metal tube is made of aluminum. (9) The fiber-reinforced tubular member according to claim (3), wherein the reinforcing fiber layer contains graphite fibers. (10) (a) preparing a cylindrical metal tube having a longitudinal axis; (b) applying an isolation layer around the outer surface of the metal tube; and (c) applying an isolation layer around the circumference of the metal tube. (d) applying a reinforcing fiber layer around the outer surface of the isolation layer by positioning a plurality of evenly spaced individual independent reinforcing fibers; and (d) applying a covering layer around the outer surface of the reinforcing fiber layer. (e) applying a liquid resin material to the isolation layer, the reinforcing fiber layer, and the coating layer; (f) firmly adhering the isolation layer, the reinforcing fiber layer, and the coating layer to the metal tube; curing a liquid resin material to form a fiber-reinforced sleeve. (11) The method for manufacturing a fiber-reinforced tubular member according to claim (10), wherein step (c) includes a step of positioning individual reinforcing fibers parallel to the longitudinal axis of the metal tube. (12) (a) providing a cylindrical metal tube having a longitudinal axis; (b) applying an isolation layer of fabric material around the outer surface of the metal tube; (d) applying a reinforcing fiber layer around the outer surface of the isolation layer by locating a plurality of individual reinforcing fibers parallel to the longitudinal axis and evenly spaced around the periphery of the metal tube;
(e) applying a liquid resin material to the isolation layer, the reinforcing fiber layer, and the coating layer; (f) the isolation layer; layer, the reinforcing fiber layer, and the covering layer to firmly adhere to the metal tube to form a fiber reinforced sleeve.
curing a liquid resin material. (13) Following step (a), a step of sending the metal tube along the vertical path is provided, and steps (b), (c), (d), and (e) are carried out so that the metal tube is fed along the vertical path. A method for manufacturing a fiber-reinforced tubular member according to claim (12), which is carried out while the member is being moved. (14) Following step (f), the step of stripping selected portions of the fiber-reinforced sleeve from at least one end of the fiber-reinforced tubular member to provide an exposed metal surface. ) The method for manufacturing a fiber-reinforced tubular member described in item 2. (15) (a) preparing a plurality of cylindrical metal tubes, each having a longitudinal axis; and (b) connecting the plurality of metal tubes to form a series of vertically extending metal tubes; (c) feeding the series of connected metal tubes along a vertical path; and (d) applying a reinforcing fiber layer around the outer surface of the connected metal tubes as the metal tubes move through the vertical path. and (e) cutting the series of metal tubes to form a plurality of individual fiber-reinforced tubular members. (16) (a) preparing a plurality of cylindrical metal tubes having vertical axes, and (b) connecting the plurality of metal tubes with a plurality of connecting plug members to form a series of metal tubes extending in the vertical direction; (c) feeding the series of connected metal tubes along a longitudinal path; and (d) moving the series of metal tubes in the longitudinal path around an outer surface of the connected metal tubes. When doing,
(e) applying a liquid resin material to the reinforcing fiber layer; and (f) firmly adhering the reinforcing fiber layer to the series of metal tubes to form a fiber reinforced sleeve. curing the liquid resin material; and (g) cutting the series of metal tubes at each of the connecting plug members to produce a plurality of individual fiber-reinforced tubular members. Law. (17) A patent claim in which the step (d) includes the step of first applying an isolation layer made of cloth material around the outer surface of the metal tube, and the reinforcing fiber layer is applied to the outer surface of the isolation layer. The method for producing a fiber-reinforced tubular member according to item (16). (18) The fiber-reinforced tubular member according to claim (16), wherein the step (d) is followed by a step of applying a coating layer made of a fiber material around the outer surface of the reinforcing fiber layer. Manufacturing method. (19) In step (d), positioning the individual reinforcing fibers evenly around the periphery of the metal tube such that the plurality of individual reinforcing fibers are parallel to the longitudinal axis of the metal tube. A method for manufacturing a fiber-reinforced tubular member according to claim (16). (20) Subsequent to step (g), the step of peeling selected portions of the fiber-reinforced sleeve from at least one end of the fiber-reinforced tubular member to provide an exposed metal end surface is provided. 16) The method for producing a fiber-reinforced tubular member according to item 16). (21) (a) preparing a cylindrical metal tube; (b) preparing a pre-formed fiber-reinforced sleeve;
A method for manufacturing a fiber-reinforced tubular member, comprising the steps of (c) positioning the fiber-reinforced sleeve so as to cover the metal tube; and (d) fixing the sleeve to the metal tube. (22) (a) preparing a cylindrical metal tube; (b) preparing a pre-formed fiber-reinforced sleeve impregnated with hardened resin; and (c) a portion of the outer surface of the metal tube. (d) positioning the fiber-reinforced sleeve so as to cover the metal tube adjacent to the adhesive and fixing the fiber-reinforced sleeve to the metal tube. Part manufacturing method. (23) The fibers according to claim (22), wherein the fiber-reinforced sleeve prepared in step (b) contains a plurality of individual reinforcing fibers parallel to the longitudinal axis of the fiber-reinforced sleeve. Reinforced tubular member manufacturing method. (24) (a) preparing a cylindrical metal tube; (b) preparing a preformed fiber-reinforced sleeve containing an uncured curable resin material; and (c)
(d) curing the curable resin to firmly adhere the fiber reinforced sleeve to the metal tube. Fiber reinforced tubular member manufacturing method. (25) The fibers according to claim (24), wherein the fiber-reinforced sleeve prepared in step (b) contains a plurality of individual reinforcing fibers parallel to the longitudinal axis of the fiber-reinforced sleeve. Reinforced tubular member manufacturing method.