JPH0791434A - Propeller shaft and its manufacture - Google Patents

Abstract

PURPOSE:To provide a propeller shaft which prevents increase in internal pressure of an FRP main body cylinder in the case of press-in of a metal joint and control an air column vibration in the main body cylinder, and its manufacture. CONSTITUTION:A penetration hole 5 for communicating the inside part 3 of a main body cylinder to open air is provided in at least one part of a metal joint 2 in a propeller shaft joined to the metal joint 2 by press-in in both ends of the FRP metal body cylinder 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a propeller shaft for automobiles and the like and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, there has been a strong demand for weight reduction of automobiles for the purpose of improving fuel consumption from the viewpoint of energy saving. As one of the means, it is considered to replace the propeller shaft made of metal with that made of FRP (fiber reinforced plastic). At that time, there are various kinds of reinforcing fibers to be used, for example, carbon fibers, glass fibers, aramid fibers, etc. are being studied. Among them, CFRP using carbon fibers as reinforcing fibers is particularly preferable in terms of strength and elastic modulus. (Carbon fiber reinforced plastic) is considered to be influential.

In a propeller shaft made of FRP or CFRP, the main body cylinder is made of FRP or CFRP, but since the joint is made of metal, it cannot be joined by welding like a propeller shaft made entirely of steel. It is impossible. Therefore, the metal fittings
It is joined to the FRP main body cylinder by press fitting.

[0004]

However, when the metal joints are press-fitted into both ends of the main body cylinder, the inside of the main body cylinder is in a hermetically sealed state, which may cause the following problems. First, at the time of press-fitting, the volume of the sealed main body cylinder space is reduced, so that the main body cylinder pressure is increased. Further, the propeller shaft of an automobile may be exposed to a high temperature atmosphere of about 150 ° C., but at this time, the air sealed in the main body cylinder tends to thermally expand, so that the pressure inside the main body cylinder is further increased. On the other hand, on the propeller shaft of an automobile,
Since a large torque generated from the engine is transmitted, a large stress is applied. Since the stress due to the pressure inside the main body cylinder is added to this load stress, the FRP main body cylinder is in a more severe stress state.

Further, in addition to the vibration due to the high speed rotation, the propeller shaft is vibrated in all directions accompanying the traveling of the vehicle, so that the air column vibration is generated in the sealed space in the main body cylinder to a greater or lesser extent. When this air column vibration becomes severe, it may cause noise.

An object of the present invention is to solve the above-mentioned problems of the conventional FRP propeller shaft, and to provide a propeller shaft which does not cause an increase in the pressure inside the FRP main body cylinder, and a manufacturing method thereof.

Another object is to suppress the vibration of the air column in the main body cylinder and prevent the generation of noise from the propeller shaft.

[0008]

In order to achieve the above object, the propeller shaft of the present invention is a propeller shaft in which metal joints are press-fitted to both ends of a FRP main body cylinder. The joint is provided with a through hole communicating with the inside of the main body cylinder.

The diameter of the through hole is not particularly limited in terms of allowing the pressure in the main body cylinder to escape to the outside, but in the range of 0.1 to 0.5 mm from the viewpoint of suppressing air column vibration in the main body cylinder. It is preferable to be within.

Further, in the method of manufacturing the propeller shaft according to the present invention, when the metal joint is press-fitted to the end portion of the FRP main body cylinder, the inside of the main body cylinder is passed through the through hole provided in the metal joint. The method is characterized by press-fitting while communicating with the outside air.

[0011]

In such a propeller shaft, since the inside of the main body cylinder and the outside (outside air) are always communicated with each other when the joint is press-fitted by the through hole provided in the metal joint, the air inside the main body cylinder penetrates. You can freely escape to the outside through the hole. Therefore, the pressure in the main body cylinder is maintained at the atmospheric pressure during and after the press-fitting. Further, even when the propeller shaft is exposed to high temperature, the air in the main body cylinder that has been thermally expanded freely escapes to the outside, so that the pressure in the main body cylinder does not increase.

Therefore, no stress due to the internal pressure is applied to the FRP main body cylinder, and the propeller shaft can exhibit the target strength performance as specified.

Further, even in the state of use, the inside and outside of the main body tube are always in communication with each other through the through hole. Therefore, by setting the hole diameter of the through hole within the appropriate range as described above, the through hole can be formed. The damper plays a role of the vibration of the air column, and the vibration of the air column to be generated is effectively suppressed.
Therefore, the generation of noise due to the air column vibration is also prevented.

Further, by setting the diameter of the through-hole within the above range, air can freely flow in and out, but since moisture such as rainwater can be substantially impervious, moisture in the main body cylinder can be prevented. Can be prevented and corrosion of the joint between the main body cylinder and the metal joint in the main body cylinder can be prevented.

[0015]

Embodiments of the propeller shaft of the present invention will be described below with reference to the drawings. FIG. 1 shows one end of a propeller shaft according to an embodiment of the present invention. Although the illustration of the other end is omitted, in the present embodiment, the configuration is the same as the illustrated end. In FIG. 1, reference numeral 1 denotes a FRP main body cylinder, and an outer reinforcing layer 1a for reinforcing the press-fitted joint portion is provided on the outer peripheral side of the end of the main body cylinder 1.

Metal joints 2 are joined to both ends of the main body cylinder 1 (only one end is shown in FIG. 1) by press fitting. The metal joint 2 includes an inner portion 3 of the body tube 1.
And a through hole 5 communicating with the outside 4 are provided.

Although the through hole 5 may be provided only in one metal joint 2, it is preferable that it is provided in both joints 2 from the viewpoint of suppressing air column vibration.

In the present embodiment, the through hole 5 is a hole extending straightly so that it can efficiently function as a damper for suppressing air column vibration.

The diameter of the through hole 5 is preferably set within the range of 0.1 to 0.5 mm. Within this range, it is possible to effectively prevent moisture from entering the main body cylinder 1 while having a damper function against air column vibration.

In the propeller shaft constructed as described above, when one joint 2 is already press-fitted and the other joint 2 (joint shown in the drawing) is press-fitted, the air in the main body cylinder 1 penetrates. Since it can freely go in and out through the hole 5, the pressure in the main body cylinder 1 is kept at atmospheric pressure before, during, and after press-fitting. Also, when the propeller shaft is exposed to high temperature, it is also kept at atmospheric pressure.

Therefore, no stress is applied to the main body cylinder 1 by the internal pressure of the main body cylinder 1, and the FRP main body cylinder 1 is not exposed to stress conditions more severe than the stress associated with the torque applied. .

Further, even when air column vibration is about to occur due to vibration during use, the through hole 5 for communicating the inside and outside of the main body cylinder 1
Since it functions as a damper, the air column vibration is effectively suppressed or damped, and the generation of noise is prevented.

Further, by setting the diameter of the through hole 5 to an appropriate diameter as described above, air can freely flow in and out, but moisture such as rainwater can be prevented from passing therethrough. Corrosion of the joint surface is also prevented.

As the matrix resin constituting the FRP propeller shaft of the present invention, epoxy resin, phenol resin, polyimide resin, vinyl ester resin,
Although a thermosetting resin such as unsaturated polyester is used, other resin, for example, a thermoplastic resin such as polyamide, polycarbonate or polyetherimide may be used.

The reinforcing fiber is not limited to carbon fiber, but glass fiber, aramid fiber, or the like can be used, and these can be used in combination.

In the propeller shaft of the present invention, a seal material may be provided at an appropriate position (for example, each member end position) between the FRP main body cylinder and the metal joint. A resin, a ring-shaped elastic body, a film or the like is suitable as the sealing material. By disposing such a sealing material, it is possible to more reliably prevent entry of water and the like and prevent corrosion of the joint portion.

Further, when the metal joint is press-fitted, it is necessary to hold the joint with a press-fitting jig. However, in order to surely hold the joint and to prevent the joint from being damaged by the force input, the joint is press-fitted. It is preferable to provide a locking or engaging portion for the tool. Such a locking or engaging portion can be formed by forming a step portion or a groove portion at an appropriate position on the outer surface of the joint.

Further, in order to reduce the press-fitting force of the metal joint as much as possible and efficiently press-fit, the following method is effective. Lower the temperature of the joint and raise the temperature of the end of the FRP body cylinder to press fit. Use the adhesive as a lubricant. Use a volatile liquid lubricant that does not remain after press fitting.

Further, it is possible to adjust the balance after completion of the propeller shaft by providing a balance weight mounting portion on the metal joint and adding an appropriate balance weight to the mounting portion by welding or the like. If a cooling fin is formed around the balance weight mounting portion, especially on the outer surface of the joint between the balance weight mounting portion and the FRP main body cylinder to be joined, welding at the time of joining the balance weight is performed. It is possible to prevent heat from being transferred to the FRP main body cylinder side. Furthermore, since the metal joint of the present invention is provided with a through hole, there is no expansion of air inside the main body cylinder due to welding heat when joining the balance weights,
The pressure of the air inside and outside the main body cylinder can be kept uniform.

[0030]

According to the present invention, since the through hole is provided in the metal joint so that the air can freely flow in and out between the inside and the outside of the FRP main body cylinder, the pressure inside the main body cylinder can be reduced. At the time of press-fitting and after use, the pressure can be maintained at the atmospheric pressure, and it is possible to prevent the FRP main body cylinder from exhibiting the desired strength by preventing the stress applied due to the increase in the internal pressure.

Further, it is possible to effectively suppress the air column vibration that tends to occur in the main body cylinder, and prevent the generation of noise accompanying the air column vibration.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a propeller shaft according to an embodiment of the present invention.

[Explanation of symbols]

 1 FRP main body cylinder 2 Metal joint 3 Main body cylinder inside 4 Main body cylinder outside 5 Through hole

Claims (3)

[Claims] 1. In a propeller shaft in which metal joints are press-fitted to both ends of an FRP main body cylinder, at least one metal joint is provided with a through hole communicating with the inside of the main body cylinder. Characteristic propeller shaft. 2. The through hole has a hole diameter of 0.1 to 0.5 mm.
The propeller shaft of claim 1 in the range of. 3. When the metal joint is joined to the end of the FRP main body cylinder by press fitting, the inside of the main body cylinder is pressed into the outside air through a through hole provided in the metal joint. , Propeller shaft manufacturing method.