JP2020138364A - Method for manufacturing pipe body used in power transmission shaft - Google Patents

Abstract

To provide a method for manufacturing a pipe body used in a power transmission shaft without using a mandrel.SOLUTION: A method for manufacturing a pipe body 102 that is made of a fiber-reinforced plastic and is used in a power transmission shaft 101 includes: a base material manufacturing step of manufacturing a plurality of base materials 2 extending in a shaft direction; a cylindrical body manufacturing step of combining the plurality of base materials 2 to manufacture a cylindrical body 12; and a winding step of winding a continuous fiber impregnated with a resin on the outer peripheral surface of the cylindrical body 12.SELECTED DRAWING: Figure 6

Description

The present invention relates to a method for manufacturing a tubular body used for a power transmission shaft.

The power transmission shaft (propeller shaft) mounted on the vehicle is provided with a pipe body extending in the front-rear direction of the vehicle, and the power generated by the prime mover and decelerated by the transmission is transmitted to the final reduction gear by this pipe body. There is.
As a tube body used for such a power transmission shaft, there is a tube body made of fiber reinforced plastic. As a method for manufacturing a tube body made of fiber reinforced plastic and used for a power transmission shaft, for example, continuous fibers impregnated with a thermosetting resin are wound around a mandrel in multiple layers to form a tubular molded body. After that, the molded body is heated to cure the resin, and a tubular tube body is formed. Then, the mandrel is pulled out from the opening at the end of the hardened tube, and the manufacturing process is completed (see Patent Document 1 below).

Japanese Unexamined Patent Publication No. 3-265738

By the way, regarding the shape of the tubular body, in recent years, it has been studied to make the central portion bulge outward in the radial direction rather than the both end portions, so-called barrel shape (barrel shape).
However, when an attempt is made to form a power transmission shaft having the above-mentioned shape using a barrel-shaped mandrel, the central portion of the mandrel bulges outward and cannot pass through the opening of the tube body, and the mandrel cannot be pulled out from the tube body. Therefore, there is a demand for a new manufacturing method capable of manufacturing a tube without using a mandrel.

The present invention has been created to solve such a problem, and an object of the present invention is to provide a method for manufacturing a tube body used for a power transmission shaft capable of manufacturing a tube body without using a mandrel.

In order to solve the above problems, the present invention is a method for manufacturing a tube body made of fiber reinforced plastic and used for a power transmission shaft, which comprises a base material manufacturing process for manufacturing a plurality of base materials extending in the axial direction. It is characterized by including a tubular body manufacturing step of manufacturing a tubular body by combining the plurality of base materials, and a winding step of winding continuous fibers impregnated with a resin around the outer peripheral surface of the tubular body.

According to the present invention, it is possible to manufacture a tube body used for a power transmission shaft without using a mandrel.

It is a side view which looked at the power transmission shaft from the side. It is sectional drawing which cut the main body part of a tube body in the axial direction. It is a flowchart which shows the manufacturing process of the pipe body which concerns on 1st Embodiment. It is a figure which shows the base material manufacturing process in the manufacturing process of the tube body which concerns on 1st Embodiment. It is a side view of the tubular body manufactured by the tubular body manufacturing process in the manufacturing process of the tubular body which concerns on 1st Embodiment. It is a figure which shows the winding process in the manufacturing process of the tube body which concerns on 1st Embodiment. It is a side view of the tubular body manufactured by the tubular body manufacturing process in the manufacturing process of the tubular body which concerns on 2nd Embodiment. It is a figure which shows the winding process in the manufacturing process of the tube body which concerns on 2nd Embodiment. It is a partial sectional view which shows the front end side of the tubular body manufactured by the tubular body manufacturing process in the manufacturing process of the tubular body which concerns on 3rd Embodiment. It is a side view which shows the rear part of the tubular body manufactured by the tubular body manufacturing process in the manufacturing process of the tubular body which concerns on 4th Embodiment.

Next, a method of manufacturing a tube body used for the power transmission shaft in each embodiment will be described with reference to the drawings. The technical elements common to each embodiment are designated by a common reference numeral, and the description thereof will be omitted. First, a power transmission shaft having a tube body manufactured by each manufacturing method will be described.

[Power transmission shaft]
As shown in FIG. 1, the power transmission shaft 101 is a propeller shaft mounted on an FF (Front-engine Front-drive) -based four-wheel drive vehicle.
The power transmission shaft 101 includes a substantially cylindrical pipe body 102 extending in the front-rear direction of the vehicle, a cardan joint stub yoke 103 joined to the front end of the pipe body 102, and a constant velocity joint joined to the rear end of the pipe body 102. The stub shaft 104 is provided.
The stub yoke 103 is a connecting member that connects the transmission mounted on the front portion of the vehicle body and the pipe body 102. The stub shaft 104 is a connecting member that connects the final speed reducing device mounted on the rear portion of the vehicle body and the pipe body 102.
When power (torque) is transmitted from the transmission, the power transmission shaft 101 rotates around the axis O1 and transmits the power to the final speed reducer.

The tubular body 102 is made of carbon fiber reinforced plastic (CFRP).
Inside the tubular body 102, a fiber layer made of fibers wound around the axis O1 and a fiber layer made of fibers extending in the axis O1 direction are laminated. Therefore, the tubular body 102 has high mechanical strength and is highly elastic in the axis O1 direction.
Further, PAN-based (Polyacrylonitrile) fibers are preferable as the fibers oriented in the circumferential direction, and pitch fibers are preferable as the fibers oriented in the axis O1 direction.
The reinforcing fibers used for the fiber reinforced plastic in the tubular body 102 of the present invention are not limited to carbon fibers, but may be glass fibers or aramid fibers.
The tubular body 102 includes a main body 110, a first connection 120 arranged on the front side of the main body 110, a second connection 130 arranged on the rear side of the main body 110, and a second connection with the main body 110. It is provided with an inclined portion 140 located between the portions 130.

In the drawings after FIG. 2, the shape of the pipe body 102 is exaggerated in order to make the shape of the pipe body 102 easy to understand.
As shown in FIG. 2, the first connecting portion 120 is continuous with the front end portion 111 of the main body portion 110, and the inclined portion 140 is continuous with the rear end portion 112 of the main body portion 110.

When the main body 110 is cut along a plane having the axis O1 as the normal, the cross-sectional shape of the outer peripheral surface 114 and the cross-sectional shape of the inner peripheral surface 115 of the main body 110 are circular.

The outer diameter of the main body 110 is reduced from the central 113 toward both ends (front end 111 and rear end 112), and the outer diameter R1 of the central 113 is both ends (front end 111). And the outer diameter R2 of the rear end portion 112).
When the main body 110 is cut along the axis O1, the cross-sectional shape of the outer peripheral surface 114 and the cross-sectional shape of the inner peripheral surface 115 of the main body 110 draw a gentle curve, and the central portion 113 protrudes outward. It has an arc shape. Therefore, the outer shape of the main body 110 has a barrel shape (barrel shape) in which the central portion 113 bulges outward in the radial direction.
Further, the inner diameter of the main body 110 is also reduced from the central 113 of the main body 110 toward both ends (front end 111 and rear end 112).
Further, in the cross-sectional shape, the plate thickness of the main body portion 110 becomes thinner from both end portions (front end portion 111 and rear end portion 112) toward the central portion 113, and the plate thickness T1 of the central portion 113 is It is thinner than the plate thickness T2 at both ends (front end 111 and rear end 112).

As shown in FIG. 1, the shaft portion 103a of the stub yoke 103 is fitted in the first connecting portion 120. The outer peripheral surface of the shaft portion 103a is formed in a polygonal shape. The inner peripheral surface of the first connecting portion 120 is formed in a polygonal shape that follows the outer peripheral surface of the shaft portion 103a. Therefore, the stub yoke 103 and the tube body 102 are configured so as not to rotate relative to each other.
The shaft portion 104a of the stub shaft 104 is fitted in the second connecting portion 130. The outer peripheral surface of the shaft portion 104a of the stub shaft 104 is formed in a polygonal shape. The inner peripheral surface of the second connecting portion 130 is formed in a polygonal shape that follows the outer peripheral surface of the shaft portion 104a of the stub shaft 104. Therefore, the tube body 102 and the stub shaft 104 are configured so as not to rotate relative to each other.

The outer diameter of the inclined portion 140 gradually decreases from the main body portion 110 toward the second connecting portion 130, forming a truncated cone shape. The plate thickness of the inclined portion 140 gradually decreases from the end portion on the second connecting portion 130 side (rear side) toward the end portion on the main body portion 110 side (front side). Therefore, the thickness of the front end portion of the inclined portion 140 is the thinnest, forming a fragile portion.
Therefore, when the vehicle is collided from the front and a collision load is input to the pipe body 102, a shearing force acts on the inclined portion 140 that is inclined with respect to the axis O1. Then, when the shearing force acting on the inclined portion 140 exceeds a predetermined value, the front end portion (fragile portion) of the inclined portion 140 is damaged. Therefore, in the event of a vehicle collision, the engine and transmission mounted on the front part of the vehicle body quickly retract, and the collision energy is absorbed by the front part of the vehicle body.

In the tubular body 102, as shown in FIG. 2, the central portion 113 of the main body portion 110 in which bending stress is easily concentrated has an outer diameter R1 formed to have a large diameter and has a predetermined bending strength. On the other hand, both ends (front end 111 and rear end 112) of the main body 110 where bending stress is difficult to concentrate are formed with a small outer diameter R2 to reduce the weight. Further, the central portion 113 of the main body portion 110 has a thin plate thickness T1 and is lightweight. Therefore, in the tubular body 102, the weight of the main body 110 is reduced while ensuring a predetermined flexural rigidity of the central portion 113, and the bending primary resonance point is improved.

[First Embodiment]
As shown in FIG. 3, the method of manufacturing the tubular body 102 used for the power transmission shaft 101 in the first embodiment includes a base material manufacturing step (step S1) for manufacturing a plurality of base materials 2 and manufacturing a tubular body 12. It includes a tubular body manufacturing step (step S2), a winding step of winding continuous fibers (step S3), and a curing step of curing the resin (step S4).

(Base material manufacturing process)
In the base material manufacturing process of the first embodiment, as shown in FIG. 4, a fiber-reinforced resin plate in which reinforcing fibers are arranged is formed by a pair of molds (only one lower mold 1 is shown in FIG. 4). Press molding is performed to manufacture the base material 2.
The resin of the fiber-reinforced resin plate in the present embodiment is a thermoplastic resin, and press molding is performed after heating the fiber-reinforced resin plate to make the resin melted.

The base material 2 manufactured in this step is a component that is long in one direction, and the first connection portion base 3, the main body portion base 4, and the inclined portion base 5 are in order from one end to the other end in the longitudinal direction. , And a base 6 for the second connecting portion is formed.

The cross-sectional shape of the first connection portion base 3, the main body portion base 4, the inclined portion base portion 5, and the second connection portion base portion 6 cut by a plane having the axis O1 as a normal is formed in a semicircular shape. Has been done.
The base portion 3 for the first connecting portion is a portion that becomes an inner peripheral portion of the first connecting portion 120 of the tubular body 102. The main body portion base 4 is a portion that serves as an inner peripheral portion of the main body portion 110. The inclined portion base portion 5 is a portion that becomes an inner peripheral portion of the inclined portion 140. The base portion 6 for the second connecting portion is a portion that becomes an inner peripheral portion of the second connecting portion 130.
Further, the thickness of each portion of the first connection portion base portion 3, the main body portion base portion 4, the inclined portion base portion 5, and the second connection portion base portion 6 is formed to be constant.

(Cylindrical manufacturing process)
In the tubular body manufacturing step of the first embodiment, as shown in FIG. 5, the mating surfaces 7 of the two base materials 2 are adhered to each other with an adhesive to manufacture a tubular tubular body 12.
The tubular body 12 manufactured in this step has, in order from one end side to the other end side, the first connecting portion cylinder portion 13, the main body portion cylinder portion 14, the inclined portion cylinder portion 15, and the second connecting portion. A cylinder portion 16 is provided.
The tubular portion 13 for the first connecting portion has a cylindrical shape. The cylinder portion 14 for the main body portion has a so-called barrel shape (barrel shape). The inclined portion cylinder portion 15 has a truncated cone shape. The tubular portion 16 for the second connecting portion has a cylindrical shape.

(Wrapping process)
In the winding step of the first embodiment, as shown in FIG. 6, the reinforcing fiber 21 impregnated with the resin is wound around the tubular body 12 by the filament winding method. As a result, a reinforcing fiber layer forming the outer peripheral portion of the tubular body 102 is formed on the outer peripheral side of the tubular body 12.
The winding device 20 used in this step is a moving supply of a plurality of bobbins 22 in which strands constituting the reinforcing fiber 21 are wound, a resin impregnated portion 23 for storing the molten thermoplastic resin, and an aggregation portion 24. A portion 25 and a rotating device 26 for rotating the tubular body 12 are provided.

Strands are drawn out from the plurality of bobbins 22, and the strands are impregnated with the thermoplastic resin by the resin impregnating portion 23. Next, the plurality of strands are aggregated by the aggregation portion 24 to form one reinforcing fiber 21. Further, the mobile supply unit 25 supports the reinforcing fibers 21 so as to be insertable.
The rotating device 26 includes a columnar rotating shaft 27, and the rotating shaft 27 is inserted into the tubular body 12 to fit the rotating shaft 27 into the tubular body 12. Then, the cylinder body 12 is rotated by the rotating device 26, and the reinforcing fibers 21 are wound around the cylinder body 12 to form the reinforcing fiber layer.

Further, the moving supply unit 25 is reciprocated in the axis O2 direction to adjust the winding amount of the reinforcing fiber 21 around the cylinder body 12 for the first connection portion cylinder portion 13, the inclined portion cylinder portion 15, and the second connection portion. Adjust so that each of the tubular portions 16 is uniform. Further, the winding amount of the reinforcing fiber 21 around the cylinder portion 14 for the main body portion is set so that the winding amount gradually decreases from the central portion toward both ends. After winding, the tubular body 12 is removed from the rotating shaft 27.

(Curing process)
In the curing step of the first embodiment, the reinforcing fiber layer is cooled by heat dissipation, and the resin of the reinforcing fiber layer is cured. According to this, a part of the resin of the reinforcing fiber layer is welded to the tubular body 12, and the reinforcing fiber layer and the tubular body 12 are integrated to manufacture the tubular body 102 used for the power transmission shaft 101.

As described above, according to the first embodiment, the pipe body 102 having the barrel-shaped (barrel-shaped) main body 110 can be manufactured, and it is not necessary to use the barrel-shaped mandrel.

[Second Embodiment]
Next, a method of manufacturing the tubular body 102 of the second embodiment will be described.
The method for manufacturing the tubular body 102 in the second embodiment includes a base material manufacturing step (step S1) for manufacturing a plurality of base materials 2, a tubular body manufacturing step for manufacturing a tubular body 12 (step S2), and impregnation with a resin. It includes a winding step (step S3) for winding the continuous fibers and a curing step (step S4) for curing the resin (see FIG. 3). Hereinafter, the differences from the first embodiment will be described.

As shown in FIG. 7, in the base material manufacturing step (step S1) of the second embodiment, the convex portion 7a and the concave portion 7b are formed on the mating surface 7 of the base material 2 formed by press molding. Further, in the tubular body manufacturing step (step S2), when the two base materials 2 are combined, the convex portion 7a of one base material 2 is fitted into the concave portion 7b of the other base material 2. As a result, the two base materials 2 can be integrated without using an adhesive. Further, the convex portion 7a and the concave portion 7b can be aligned, and the tubular body 12 can be manufactured with high accuracy.

As shown in FIG. 8, in the winding step (step S3) of the second embodiment, the tubular body 12 rotated by the rotating device 26 is in the form of a sheet obtained by impregnating the reinforcing fibers with a resin (thermosetting resin). The prepreg 28 is wound by using a plurality of crimping rollers 29.
According to such a sheet winding method, the reinforcing fibers in the sheet can be extended along the axial direction, and the bending strength of the tubular body 102 can be improved.

As described above, according to the second embodiment, the pipe body 102 having the barrel-shaped (barrel-shaped) main body 110 can be manufactured, and it is not necessary to use the barrel-shaped mandrel.

[Third Embodiment]
The method for manufacturing the tubular body 102 in the third embodiment includes a base material manufacturing step (step S1) for manufacturing a plurality of base materials 2, a tubular body manufacturing step for manufacturing a tubular body 12 (step S2), and winding continuous fibers. It includes a winding step (step S3) and a curing step (step S4) for curing the resin (see FIG. 3). Hereinafter, the differences from the first embodiment will be described.

In the base material manufacturing step (step S1) of the third embodiment, the base material 2 is manufactured by Resin Transfer Molding molding (hereinafter referred to as “RTM molding”) instead of press molding. The RTM molding is a method of arranging reinforcing fibers in a pair of molds, injecting molten resin into the mold after molding, and manufacturing the base material 2 while impregnating the reinforcing fibers with the resin.

As shown in FIG. 9, the base material manufacturing step (step S1) of the third embodiment manufactures the base material 2 in which the semicircular arc-shaped protrusions 8 protruding outward in the axial direction from both end faces are formed. When combined, the protrusions 8 form a cylindrical protrusion 18 in the tubular body manufacturing process (step S2).
Then, in the tubular body manufacturing step (step S2) of the third embodiment, after combining the two base materials 2, the protrusion 18 is fitted inside the outer tubular portion 102a of the stub yoke 102. Further, although not particularly shown, the protrusion formed at the rear end of the tubular body 12 is fitted inside the outer tubular portion of the stub shaft 103 (not shown). As a result, the two base materials 2 can be integrated without using an adhesive.
In the winding step (step S3) of the third embodiment, the reinforcing fibers are applied not only to the outer peripheral side of the tubular body 12, but also to the outer peripheral side of the outer cylinder portion 102a of the stub yoke 102 and the outer cylinder portion (not shown) of the stub shaft 103. It is wrapped to form a reinforcing fiber layer. Therefore, in the curing step (step S4), the reinforcing fiber layer is welded to the stub yoke 102 and the stub shaft 103.

As described above, according to the third embodiment, the pipe body 102 having the barrel-shaped (barrel-shaped) main body 110 can be manufactured, and it is not necessary to use the barrel-shaped mandrel.

[Fourth Embodiment]
The method for manufacturing the tubular body 102 in the fourth embodiment includes a base material manufacturing step (step S1) for manufacturing a plurality of base materials 2, a tubular body manufacturing step (step S2) for manufacturing a tubular body 12, and continuous fibers. It includes a winding step (step S3) and a curing step (step S4) of curing the resin (see FIG. 3). Hereinafter, the differences from the first embodiment will be described.

As shown in FIG. 10, in the tubular body manufacturing step (step S2) of the fourth embodiment, after the tubular body 12 is formed by combining the two base materials 2, the inside of the tubular covering film 40 made of rubber. The rear portion of the tubular body 12 is inserted into the body, and the tubular portion 15 for the inclined portion is covered with the coating film 40.
According to this, the rear side of the two base materials 2 can be integrated. Further, since the outer peripheral surface of the inclined portion tubular portion 15 is inclined, the reinforcing fibers wound around the inclined portion tubular portion 15 may slip in the winding step (step S3) and may not be oriented as desired. The friction of the coating film 40 makes the reinforcing fibers less slippery.

As described above, according to the fourth embodiment, the pipe body 102 having the barrel-shaped (barrel-shaped) main body 110 can be manufactured, and it is not necessary to use the barrel-shaped mandrel.

Although each embodiment has been described above, the present invention is not limited to the examples described in the embodiments.
For example, the first connecting portion cylinder portion 13 and the second connecting portion cylinder portion 16 are formed in a cylindrical shape, but may be formed in a polygonal shape. According to this, the inner peripheral surfaces of the first connecting portion 120 and the second connecting portion 130 of the pipe body 102 have a polygonal shape. Then, by forming the insertion portion of the stub yoke 102 or the stub shaft 103 inserted into the first connection portion 120 or the second connection portion 130 into a polygonal shape, it is possible to make it difficult to rotate relative to each other.
Further, in the third embodiment, the cross-sectional shape of the protrusion 18 may be a polygonal shape. The outer cylinder portion 102a of the stub yoke 102 may also have a polygonal shape, making it difficult for the stub yoke 102 to rotate relative to each other.

Further, in the embodiment, an example in which a thermoplastic resin is used for the resin constituting the tubular body 12 and the resin impregnated with the reinforcing fibers has been given, but in the present invention, a thermosetting resin may be used.
Further, in the embodiment, the tubular body 12 is composed of two base materials 2, but the present invention is not particularly limited as long as a plurality of base materials can be prepared. For example, four base materials having a quadrant in cross section are used. The tubular body 12 may be manufactured in combination.

Further, the main body 110 of the pipe body 102 manufactured in the embodiment has a barrel shape (barrel shape) in which the diameter is reduced from the central portion 113 toward both end portions (front end portion 111 and rear end portion 112). However, for example, the main body portion may have a constant diameter from the front end portion 111 to the rear end portion 112. Alternatively, the diameter from the front end portion 111 to the central portion 113 may be constant, and the diameter may be reduced from the central portion 113 to the rear end portion 112.

Further, the tube body manufactured by the manufacturing method of the present invention is not limited to the above-mentioned one. For example, with respect to the inclined portion 140, the plate thickness may be gradually reduced from the end portion on the main body portion 110 side (front side) toward the end portion on the second connection portion 130 side (rear side). According to this, the plate thickness of the rear end portion of the inclined portion 140 is the thinnest, and the rear end portion of the inclined portion 140 constitutes a fragile portion. Alternatively, a fragile portion may be formed by providing a recess on the outer peripheral surface or the inner peripheral surface of the inclined portion 140 and changing the plate thickness of a part of the section.

1 Lower mold 2 Base material 3 First connection base 4 Main body base 5 Tilt base 6 Second connection base 12 Cylindrical body 13 First connection tube 14 Main body tube 15 Tilt Cylinder part 16 Cylinder part for second connection part 50 Coating film 101 Power transmission shaft 102 Tube body 103 Stub yoke 104 Stub shaft 110 Main body part 120 First connection part 130 Second connection part 140 Inclined part

Claims (6)

A method for manufacturing a tube body made of fiber reinforced plastic and used for a power transmission shaft.
A base material manufacturing process for manufacturing a plurality of base materials extending in the axial direction,
A tubular body manufacturing process for manufacturing a tubular body by combining the plurality of base materials,
A winding step of winding continuous fibers impregnated with resin around the outer peripheral surface of the cylinder, and
A method for manufacturing a tube body used for a power transmission shaft, which comprises. The method for manufacturing a tube body used for a power transmission shaft according to claim 1, wherein the fiber reinforced plastic is a carbon fiber reinforced plastic. In the base material manufacturing process, two semicircular base materials viewed from the axial direction are manufactured.
The method for manufacturing a tubular body used for a power transmission shaft according to claim 1 or 2, wherein in the tubular body manufacturing step, the tubular body is manufactured by combining the two base materials. The method for manufacturing a tubular body used for a power transmission shaft according to any one of claims 1 to 3, wherein the base material manufacturing step is to manufacture the base material by press molding or RTM molding. .. The method for manufacturing a tube body used for a power transmission shaft according to any one of claims 1 to 4, wherein the winding method in the winding step is a filament winding method or a sheet winding method. The tubular body includes a main body and a connecting portion that is continuous with the end of the main body and to which a connecting member is connected.
The pipe used for the power transmission shaft according to any one of claims 1 to 5, wherein the outer diameter of the main body is reduced from the central portion toward both ends. How to make a body.

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