JPH0632726U - Fiber-reinforced plastic drive shaft - Google Patents

Abstract

(57) [Summary] [Purpose] To provide a drive shaft made of FRP which has a large torque strength and can withstand repeated use for a long period of time. [Structure] A sleeve 2A of a metal yoke is inserted and fixed in both ends of a fiber-reinforced plastic tube 1, and a metal outer collar 3 is externally fitted and tightened in both ends of the tube 1. The metal outer collar 3 is welded to the flange 2B of the metal yoke.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a drive shaft for transmitting torque such as a propeller shaft and a drive shaft of an automobile, and more particularly to a drive shaft made of fiber reinforced plastic (hereinafter abbreviated as "FRP").

[0002]

[Prior art]

 In recent years, automobiles have been increasingly required to be lightweight from the viewpoint of environmental protection and energy saving, and a shift to lightweight materials is being considered. One of them is the application of FRP to drive shafts for torque transmission such as propeller shafts and drive shafts, which not only reduces weight by improving specific rigidity and strength, but also improves riding comfort by increasing vibration damping. Can be expected, and it is intended for practical use.

By the way, when the FRP tube is used as a drive shaft for torque transmission, the most important technical issue is how to join the metal yokes at both ends. This requires the joint to have sufficient strength for the torque transmitted by the drive shaft, but in the case of FRP drive shafts, it is applied in the case of metal drive shafts. Ordinary means (such as welding) cannot be applied. Therefore, various joining methods have been conventionally proposed.

The simplest method is a method using an adhesive. For example, in Japanese Patent Publication No. 61-54965, a fiber of an FRP tube is impregnated with a synthetic resin agent, and a metal yoke is formed by the synthetic resin agent. A method of bonding has been proposed. Also, a sleeve having a large number of sharp pins arranged in a radial pattern (Japanese Patent Laid-Open No. 55-159310) and a method in which teeth are provided on the outer circumference of the sleeve to be engaged with the inner surface of the FRP tube (Japanese Patent Publication No. No. 62-53373), one in which the joint portion of the FRP tube and the sleeve is polygonal (Japanese Patent Laid-Open No. 55-159314), etc., to enhance the joint strength by utilizing mechanical engagement. Alternatively, bolts (Japanese Utility Model Laid-Open No. 58-90830) and outer collars (Japanese Utility Model Laid-Open No. 61-162619) are used to fix the joints.

[0005]

[Problems to be solved by the device]

 However, each of the above-mentioned related arts has the following problems. That is, in the joining method using only an adhesive as in Japanese Patent Publication No. 61-54965, since the joining strength is low, a long sleeve is required to obtain a desired joining strength, and it is impossible to reduce the weight. . Moreover, it lacks reliability for repeated use over a long period of time. The one disclosed in Japanese Patent Laid-Open No. 55-159310 has a large stress concentration at the portion of the inner wall surface of the FRP tube that contacts the pin tip, and cannot withstand repeated use. The one disclosed in Japanese Examined Patent Publication No. 62-53373 has a risk that the fibers may be cut at the part where the teeth come into contact with each other, and cracks are likely to occur due to stress concentration. In the case of the one disclosed in JP-A-55-159314, the contact at the corner becomes stronger and the generated stress increases. In the bolt fastening method as disclosed in Japanese Utility Model Laid-Open No. 58-90830, stress concentration occurs around the hole, and the fibers of the FRP tube may be cut. The method using an outer collar as in Japanese Utility Model Laid-Open No. 61-162 619 is expected only to act as a reinforcement when press-fitting or using bolts, and does not itself produce a joining force.

Therefore, an object of the present invention is to provide a drive shaft made of FRP which has a large torque strength and can withstand repeated use for a long period of time.

[0007]

[Means for Solving the Problems]

 The above-mentioned problem is a drive shaft in which sleeves of metal yokes are inserted and fixed in both ends of a fiber reinforced plastic tube, and metal outer collars are externally fitted and tightened in both ends of the tube. This can be solved by welding the outer collar to the flange of the metal yoke.

[0008]

[Action]

 In the present invention, the sleeve of the metal yoke is inserted and fixed in both ends of the FRP tube, and the metal outer collar is fitted and tightened on both ends of the tube. Since the welding is performed on the flange of the metal yoke, the transmission torque is shared not only by the FRP tube and the sleeve of the metal yoke but also by the friction force between the metal outer collar and the FRP tube through the flange of the metal yoke. The strength is significantly improved, and it can withstand repeated use over a long period of time.

[0009]

【Example】

 Hereinafter, the present invention will be described in more detail with reference to the drawings. FIG. 1 is a vertical sectional view showing an embodiment of the present invention, and FIG. 2 is a vertical sectional view showing a conventional example. Is a metal outer color.

The conventional FRP drive shaft shown in FIG. 2 is manufactured by press-fitting the yoke sleeves 2 A into both ends of the FRP tube 1 in which the metal outer collar 3 is loosely fitted in advance. In this case, the metal outer collar 3 has a function of tightening the FRP tube 1 on the outer circumference of the yoke sleeve 2A to prevent the FRP tube 1 from expanding due to elastic deformation. However, in the above-mentioned conventional FRP drive shaft, the metal outer collar 3 and the yoke sleeve 2A are not fixed. Therefore, when a strength test applying a torsion torque is performed, a slip between the FRP tube 1 and the yoke sleeve 2A occurs. Occurs and the joint is destroyed.

Therefore, in the present invention, as shown in FIG. 1, the metal outer collar 3 is welded to the yoke flange 2 B and is joined by the welding beats 4. As a result, the torque is shared not only by the FRP tube 1 and the yoke sleeve 2A but also by the frictional force between the metal outer collar 3 and the FRP tube 1, so that the slip torque strength is greatly improved and repeated for a long time. It can be used well.

Example 1 Next, the effect of the present invention will be clarified by an example. As an FRP tube 1, a prototype of an outer diameter φ110 mm, an inner diameter φ95 mm, a hybrid structure of materials CFRP and GF RP was prototyped, and S45 C sleeve 2A was press-fitted into both ends with a press-fitting margin of 0.4 mm. I made two types of two.

Then, when a strength test was conducted, it was found that the one in FIG. 2 slipped at 1200 kgm, while the one in FIG. 1 could withstand a torque of 1900 kgm.

[0014]

[Effect of device]

 As described above, according to the present invention, since the slip torque strength can be greatly improved, it is possible to sufficiently withstand repeated use for a long period of time.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the present invention.

FIG. 2 is a vertical sectional view showing a conventional example.

[Explanation of symbols]

1 ... FRP tube, 2 ... metal yoke, 3 ... metal outer collar, 4 ... welding beet.

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Claims (1)

[Scope of utility model registration request] 1. A drive shaft in which a sleeve of a metal yoke is inserted and fixed in both ends of a fiber reinforced plastic tube, and a metal outer collar is externally fitted and tightened in both ends of the tube. A drive shaft made of fiber reinforced plastic, wherein a collar is welded to the flange of the metal yoke.