JPH0587115A - Manufacture of power transmission shaft - Google Patents

Abstract

PURPOSE:To wind the fiber material efficiently without the constraint by a spider fitting hole of a yoke. CONSTITUTION:A yoke 12, in which a twisted part 17 is provided in the rear of a spider fitting hole 15, is connected to both ends of a thin and hollow mandrel 11 to form a sub assembly 10. The sub assembly 10 is rotated around of a support shaft 19 unified with a core of the yoke 12, and the fiber material 20 impregnated with resin is wound over the twisted part 17 of the yoke 12 and the mandrel 11. The resin impregnated in the fiber material 20 is heated for hardening, and thereafter, the support shaft 19 is removed to complete a power transmission shaft.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a power transmission shaft mainly composed of fiber reinforced plastic (FRP).

[0002]

2. Description of the Related Art For example, in a power transmission shaft used as a propeller shaft of an automobile, a yoke, which is a component of a universal joint, is joined and integrated with both ends of a hollow shaft body for practical use. Conventionally, in order to manufacture such a power transmission shaft mainly using FRP, a hollow shaft main body made of FRP is manufactured by a filament winding method or a tape winding method, and a yoke is attached to both ends of the hollow shaft main body with an adhesive. The method of joining and integrating is generally adopted.
However, according to such a manufacturing method, the joint strength between the FRP shaft main body and the yoke depends exclusively on the strength of the adhesive, and when the transmission torque is large, there is a risk of breaking from the adhesive portion, There was another problem of lack of reliability.

Therefore, for example, in Japanese Patent Application Laid-Open No. 55-118831, as shown in FIG. 4 incorporated from the publication, a central shaft 2 is preliminarily provided on a yoke 1, and the yoke 1 is provided with a thin mandrel (cylindrical cylinder). ) 3 is fitted at both ends, and the mandrel 3 is rotated about the central axis 2 while a filament winding method or the like is used to wind the resin-impregnated fiber material 4 from the yoke 1 to the mandrel. ing. According to such a manufacturing method, the yoke 1 is integrally adhered to the FRP shaft main body at the same time when the resin impregnated in the fiber material 4 is heat-cured, and the joint strength between the both is increased and its reliability is improved. Will be things.

[0004]

By the way, the yoke of the mating shaft member is connected to the yoke 1 via a spider, and normally, a mounting hole 5 (FIG. 4) for mounting the spider is provided. It is provided on the yoke 1 in advance.
Therefore, when winding the fiber material 4, care must be taken not to block the mounting hole 5. However, according to the manufacturing method disclosed in the above publication, the yoke 1
Since the fiber material 4 is wound back while the front surface of the fiber material is being wound, great care must be taken to wind the fiber material so as not to block the mounting hole 5, resulting in a decrease in productivity. There was an unavoidable problem. In particular, recently, there is a tendency to increase the number of filaments constituting the fiber material 4 in order to improve productivity, but in this case, it becomes more difficult to wind the mounting hole 5 so as not to close it, and the productivity is increased. Was to fall further. Further, if it is attempted to wind the mounting hole 5 so as not to close it, there is a risk that a region in which the fibrous material cannot be wound will occur at the joint between the yoke 1 and the mandrel 3, and there is a problem in terms of joint strength. There were many places. Although it is conceivable that the attachment hole 5 is opened after the fiber material is wound on the whole, in this case, the fiber material is cut and the overall strength reduction cannot be avoided.

The present invention has been made to solve the above-mentioned conventional problems, and an object thereof is to efficiently wind a fiber material without being restricted by a spider mounting hole provided in a yoke. Another object of the present invention is to provide a method of manufacturing a power transmission shaft.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a mandrel having a yoke having a constricted portion at a portion closer to a base end than a spider mounting hole and a support shaft at an axial center position. While the mandrel is rotated around the supporting shaft, the fiber material impregnated with resin is wound around the mandrel from the constricted part of the yoke, and then subjected to heat treatment. The resin impregnated in the fiber material is heat-cured, and then the support shaft is removed from the fitting.

In the present invention, as the above fiber material,
For example, glass fiber, carbon fiber, silicon carbide fiber, etc. can be selected, and as the resin impregnated therein, for example, epoxy resin, polyimide resin, unsaturated polyester resin, etc. can be selected. Furthermore, as a method of winding the fiber material impregnated with this resin on a mandrel,
Filament winding method using filamentous fiber material,
A tape winding method or the like using a prepreg can be adopted. Further, in the present invention, the support shaft provided on the yoke may be formed integrally with the yoke or may be detachably coupled.

[0008]

In the method of manufacturing the power transmission shaft configured as described above, since the resin-impregnated fiber material is folded back through the constricted portion provided in the yoke, it is independent of the spider mounting hole in the yoke. The fiber material can be wrapped.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

In this embodiment, first, as shown in FIG. 1, a thin hollow mandrel 11 and a yoke 12 are prepared, and a yoke is provided at both ends of the mandrel 11 (only one side is shown here).
12 is fitted to form the subassembly 10. The yoke 12 has a cup portion 13 on the fitting side (base portion side) with respect to the mandrel 11, and a small diameter portion 13a formed at the open end of the cup portion 13 is press-fitted into the mandrel 11, whereby the mandrel 11 is inserted into the mandrel 11. The outer periphery is flush with each other. In this connection, the yoke 12 may be adhesively fixed or welded to the mandrel 11. This york 12
Is used as one part of the universal joint, and its tip side is a forked arm portion 14, and a pair of mounting holes for mounting the spider that constitutes the universal joint on the arm portion 14.
15 are provided. Further, the yoke 12 is provided with a constricted portion 17 on the outer periphery of the connecting portion 16 between the cup portion 13 and the arm portion 14, and a through hole 18 is provided at the central position (axial center) of the connecting portion 16. A support shaft 19 described later is press-fitted and fixed in the hole 18.

Next, a fiber material impregnated with resin is wound around the peripheral surface of the sub-assembly 10 by the firanmethowinding method. At the time of this winding, the support shaft 19 is press-fitted and fixed in the through hole 18 of the yoke, and the support shaft 19 is gripped by the chuck portion of a firanmethowinding machine (hereinafter, simply referred to as a machine), so that the subassembly 10 Is set on the machine. Then, as shown in FIG.
While rotating the sub-assembly 10 around the center 19, a fiber jig 20 impregnated with resin is guided along the sub-assembly 10 using a guide jig (not shown), and is wound around the peripheral surface thereof. At this time,
By controlling the rotation speed of the subassembly 10 and the moving speed of the guide jig, the fiber material 20 is folded back so as to wrap around the constricted portion 17 of the yoke 12, and at the same time, the fiber material 20 has a predetermined axis relative to the axial center of the subassembly 10. The fiber material 20 is oriented at an inclination angle. In this way, the fiber material 20 is wound and laminated on the subassembly 10, and when the resin-impregnated fiber layer having a predetermined thickness is formed, the winding is stopped. Next, the sub-assembly 10 around which the fiber material is wound is removed from the machine and placed in a heating furnace.
The resin impregnated in 20 is cured. By this heat curing treatment, the resin-impregnated fiber layer becomes a fiber-reinforced plastic layer (F
RP shaft main body), at this time, the yoke 12 is firmly joined to the FRP shaft main body, and then the support shaft 19 is pulled out from the through hole 18 of the yoke 12 to complete the power transmission shaft.

In the power transmission shaft manufactured as described above, since the resin-impregnated fiber material 20 is folded back using the constricted portion 17 of the yoke 12, the mounting hole 15 of the yoke 12 is Not blocked by material. Therefore, it is possible to use the fibrous material 20 having a high degree of filament integration, and it is possible to improve productivity. Further, a region where the fiber material cannot be wound does not occur in the joint portion between the mandrel 11 and the yoke 12, and a desired strength can be secured. In this embodiment, in particular, the yoke 12 is coupled to the mandrel 11 by utilizing the small diameter portion 13a so that the outer peripheral surface is flush with each other, so that there is no step on the outer periphery of the FRP shaft main body, and as a whole, The appearance quality is improved.

According to the calculation, the allowable torque is 200 k
When the outer diameter of the joint of the yoke 12 to the mandrel 11 is 70 mm and the inner diameter of the through hole 18 of the yoke 12 is 6 mm in gf · m, if the diameter of the bottom of the necked portion 17 of the yoke 12 is about 40 mm, the shear stress It was found that a sufficient strength can be guaranteed.
Therefore, the depth of the constricted portion 17 can be set to be sufficiently deep, and the winding of the fiber material 20 will not be difficult.

In the above embodiment, the subassembly 10
Through hole 18 provided on yoke 12 with support shaft 19 that is the center of rotation of
The support shaft 19 may be provided as a part of the yoke 12, as shown in FIG. In this case, after the fiber material 20 impregnated with resin is wound around the subassembly 10 and heat-cured, the supporting shaft 19 is removed from the yoke 12 by an appropriate method to complete the power transmission shaft. However, since the through hole 18 (FIG. 1) can be eliminated, the constricted portion 17 can be set deeper, and the winding of the fiber material 20 becomes easier.

[0015]

As described above in detail, according to the method of manufacturing the power transmission shaft of the present invention, the constricted portion provided on the yoke is used to perform the spider mounting hole in the yoke regardless of the hole. It is possible to efficiently wind the fiber material, and it is possible to use the fiber material having a high degree of filament integration, and it is possible to achieve a great improvement in productivity. Further, since the winding of the fiber material is not particularly restricted, a region where the fiber material cannot be wound is not formed in the joint portion between the yoke and the mandrel, and the desired strength can be stably secured.

[Brief description of drawings]

FIG. 1 is a sectional view showing an assembled structure of a yoke and a mandrel used in the present invention.

FIG. 2 is a front view showing an intermediate stage of the present invention.

FIG. 3 is a sectional view showing another embodiment of the assembly structure of the yoke and the mandrel used in the present invention.

FIG. 4 is a front view showing an intermediate stage of manufacturing a conventional power transmission shaft.

[Explanation of symbols]

 11 Mandrel 12 Yoke 15 Mounting hole 17 Constriction 19 Support shaft 20 Fiber material impregnated with resin

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tadashi Takeuchi 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd. (72) Inventor Yoshihiro Asai 1 Toyota Town, Toyota City, Aichi Prefecture, Toyota Motor Co., Ltd.

Claims (1)

[Claims] 1. A yoke, which is provided with a constricted portion at a portion closer to a base end portion than a spider mounting hole and a support shaft is provided at an axial center position, is fitted to both end portions of a mandrel, and the yoke is centered on the support shaft. While rotating the mandrel, the resin-impregnated fiber material is wound around the mandrel from the constricted portion of the yoke, and then this is subjected to heat treatment to heat-cure the resin impregnated in the fiber material, and thereafter. A method for manufacturing a power transmission shaft, wherein the support shaft is removed from the mounting bracket.