JPH0460235A - Propeller shaft for vehicle - Google Patents

Abstract

PURPOSE:To enlarge the thickness of an elastic member without changing the outer diametral size of a propeller shaft itself by pressing the elastic member tight in a space part formed between tapers at both outer and inner cylinder member sides. CONSTITUTION:Each of tapers 13a, 13b, reducing the extent of wall thickness of an outer cylinder member 1 successively to both ends from the inward of this outer cylinder member, is given to an inner wall surface 1a being situated in and around both symmetrical ends of the outer cylinder member 1. Then, each of tapers 15a, 15b, reducing the wall thickness of an inner cylinder member successively in proportion as going to the inward of the outer cylinder member, is given to outer wall surfaces 4a, 4b of both inner cylinder members 3a, 3b inserted through from both ends of the outer cylinder member. An elastic member 7 is pressed tight in a space part 5 formed between both tapes at each side of both these inner and outer cylinder members, constituting a propeller shaft. Accordingly, thickness of the elastic member is made possible to enlarge it without changing the outer diametral size of the propeller shaft itself, thus a variable range of torsional rigidity is expanded so wide and, what is more, both vibrationproof and noiseproof properties are yet more improvable in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention comprises a substantially cylindrical elastic member interposed between an outer cylinder and an inner cylinder inserted coaxially from both ends of the outer cylinder. This relates to propeller shafts.

As is well known in the art, various types of propeller shafts are available for transmitting the driving force of an automobile engine from a transmission to a final reduction gear. Japanese Patent Application No. Hei 2-15442 discloses the structure of a propeller shaft 10 shown in FIG. This propeller shaft 10 includes an outer cylinder member 1 made of fiber-reinforced plastic with a relatively large diameter, and inner cylinder members 3a and 3b made of metal, which are located on both left and right sides of the outer cylinder member 1 and are inserted in the internal axial direction. , the outer wall surface 4a of the inner cylinder members 3a, 3b in advance.
, 4b, and are vulcanized and bonded to the respective inner cylinder members 3a, 3.
b, and elastic members 7, 7, etc., made of rubber or the like are press-fitted into the space 5 between the outer cylinder member 1 and the outer cylinder member 1.

These elastic members 7, 7... exhibit a substantially cylindrical shape, and are arranged in plural in series at predetermined intervals along the axial direction of the inner cylinder members 3a, 3b. Reference numerals 9 and 9 designate metal ball yokes connected to both left and right ends of the inner cylinder members 3a and 3b.

According to this configuration, during the rotation of the propeller shaft 10 for transmitting the driving force of the engine, the elastic members 7,
The torsional vibration characteristics of the propeller shaft 10 are improved by the elastic deformation of 7..., and the vibration damping property is improved.

Soundproofing properties can be improved.

Problems to be Solved by the Invention In such a propeller shaft 10, each elastic member 7, which is interposed between the outer cylinder member 1 and the inner cylinder members 3a, 3b,
7 Thickness 1. It is advantageous to increase the torsional vibration characteristics of the propeller shaft 10,
Vibration-proofing properties and sound-proofing properties can be further improved.

Usually, as a means to increase the thickness tl of the elastic members 7, 7..., the outer diameter and inner diameter of the outer cylinder member 1 are increased, or the outer diameter of the inner cylinder members 3a and 3b is decreased. There are several possible methods, but increasing the outer diameter of the outer cylinder member 1 would result in the outer cylinder member 1 getting used to interfering with other members as the propeller shaft 10 itself becomes larger. The outer diameter of the cylindrical member 1 cannot be increased.

On the other hand, reducing the outer diameter of the inner cylinder members 3a, 3b may reduce the torsional rigidity of the propeller shaft 10 itself, so reducing the outer diameter dimension required for the inner cylinder members 3a, 3b is also a problem. It is necessary to maintain the diameter dimension, and therefore, these means are subject to constraints in terms of performance as a propeller shaft.

Therefore, the present invention solves the problems that conventional propeller shafts for vehicles have, and increases the thickness t of the elastic member without changing the outer diameter of the propeller shaft itself, thereby improving vibration isolation and It is an object of the present invention to provide a propeller shaft that can further improve soundproofing properties.

Means for Solving the Problems In order to achieve the above object, the present invention includes an outer cylinder member having a predetermined length, and an outer cylinder member that is inserted coaxially from both ends of the outer cylinder member toward the inside of the outer cylinder member with a certain space. an inner cylinder member,
a substantially cylindrical elastic member fixed to the outer peripheral surface of the inner cylinder member, the upper surface of which presses against the inner peripheral surface of the outer cylinder member; In a vehicle propeller shaft in which a plurality of propeller shafts are arranged in series at intervals, an inner wall surface of the outer cylinder member is provided on an inner wall surface located near both left and right ends of the outer cylinder member from the inside of the outer cylinder member to both ends. A taper is provided to gradually reduce the wall thickness, and the wall thickness of the inner cylinder member is gradually reduced toward the inside of the outer cylinder member on the outer wall surface of the inner cylinder member inserted from both ends of the outer cylinder member. The propeller shaft is provided with a taper, and the elastic member is press-fitted into a space formed between the taper on the outer cylinder member side and the taper on the inner cylinder member side.

Function The propeller shaft having the above configuration allows the thickness of the elastic member to be increased without changing the outer diameter of the propeller shaft itself, and accordingly, the range of variation in torsional rigidity as a propeller shaft can be expanded. As a result, vibration-proofing properties and sound-proofing properties can be further improved.

Furthermore, the rotational torque transmitted from the outer cylinder member to the inner cylinder member is
A large rotational torque is received at a relatively thick point of this outer cylinder member, and this rotational torque is transmitted to the inner cylinder member via an elastic member, while a small Since the rotary torque is received, there is no risk that the strength of the outer cylinder member will be insufficient due to the taper formed in the outer cylinder member. Furthermore, the inner cylindrical member receives a small rotational torque by the elastic member at a point where the wall thickness is small, and receives a large rotational torque at a point where the wall thickness is relatively large. Due to the taper, there is no risk that the strength of the inner cylinder member will be insufficient.

EXAMPLE Hereinafter, an example of a propeller shaft for a vehicle according to the present invention will be described in detail, with the same reference numerals attached to the same components as those of the conventional structure.

Figure 1 shows a propeller shaft according to the present invention applied to a propulsion shaft that transmits power from an automobile engine to a final reduction gear. an outer cylindrical member 1, metal inner cylindrical members 3a and 3b on both left and right sides of the outer cylindrical member 1 and coaxially inserted in the internal axial direction, and outer wall surfaces of the inner cylindrical members 3a and 3b in advance. 4a,
4b and are vulcanized and bonded to each inner cylinder member 3a, 3b.
and an elastic member 7.7 made of rubber or the like press-fitted into the space 5 between the outer cylinder member 1 and the outer cylinder member 1.

In the case of this embodiment, both left and right ends lb, l of the outer cylinder member 1
The inner wall surface 1a located near c is provided with tapers 13a and 13b that sequentially reduce the thickness of the outer cylindrical member 1 from the inside to both ends 1b and lc.

Further, on the outer wall surfaces 4a and 4b of the inner cylinder members 3a and 3b inserted from both ends 1b and lc of the outer cylinder member 1 in the internal axial direction,
A taper 15a that gradually reduces the thickness of the inner cylinder member 3 as it goes inward of the outer cylinder member 1 from both left and right ends of the inner cylinder members 3a, 3b.

15b is given. In the space 5 formed between the tapers 13a and 13b provided on the outer cylinder member 1 side and the tapers 15a and 15b provided on the inner cylinder member 3a and 3b side, an elastic member such as the above-mentioned rubber is inserted. 7,7...
is press-fitted.

In other words, the tapers 13a, 13b and the taper 15a
, 15b are an outer cylinder member l and an inner cylinder member 3a.

Each of the elastic members 7, 7, . This is a feature of this embodiment.

The above elastic members 7, 7... have a substantially cylindrical shape,
Taper 15a of inner cylinder members 3a, 3b is preliminarily formed.

A plurality of them are arranged in series at predetermined intervals along the axial direction on the surface of 15b.

Reference numeral 9.9 denotes a metal pole yoke coupled to both left and right ends of the inner cylinder members 3a and 3b.

According to this configuration, the taper 1 formed in the outer cylinder member 1
3a, 13b and the tapers 15a, 15b formed on the inner cylinder members 3a, 3b, the thickness t2 of each elastic member 7, 7... is reduced to the thickness 1+(th) of the elastic member 7, 7... in the conventional example. It can be formed larger than that shown in Fig. 3). Therefore, it is possible to widen the variable range of the torsional rigidity of the propeller shaft 20, which is advantageous in implementing noise and vibration countermeasures.

That is, considering the change in torsional rigidity caused by increasing the wall thickness of the elastic members 7, 7, . As shown in , the outer diameter of the elastic member 7 is dl+, and the inner diameter is d2. If the total length is L, then Gs is the elastic modulus of the rubber.

Therefore, when 03 and L are constant, K is determined by the outer diameter dimension d1 and inner diameter dimension d2 of the elastic member 7.

Here, assuming that Gs is 8-18 (Kgf/cm2), the outer diameter dimension d1 of the elastic member 7 in the conventional example is 6.1 cm.

Similarly, when calculating the torsional rigidity KT when the inner diameter dimension d2 is 5.9 cm, it becomes a constant.

On the other hand, according to actual measurements, the outer diameter dimension d1 and inner diameter dimension d2 of the elastic member 7 to which this embodiment is applied is d+=6. ．． 1cm~
6.55cm d2=5. 45 cm ~5. 9 cm, and the torsional rigidity KT of the elastic member 7 having such dimensions is
2 is KT□=(8~l 8)XAX(97-540)-(0
, 18~1) × becomes the moon.

Therefore, A2, the torsional rigidity of the elastic member 7 to which this embodiment is applied can be made wider than the similar torsional rigidity KT in the conventional example, in other words, it is possible to widen the tuning range, and it can be used as a sufficient propeller shaft. It has the effect of taking measures against sound and vibration.

On the other hand, when considering the strength of the outer cylinder member 1 and the inner cylinder member 2, as shown in the model diagram of FIG. 2, the rotational torque M transmitted from the outer cylinder member l to the inner cylinder member 3a is , first A
The elastic member 7 at point B absorbs the rotational torque toward the inner cylinder member 3a, resulting in M, /2, and the elastic member 7 at point B absorbs the remaining rotational torque toward the inner cylinder member 3a, and eventually the outer cylinder member 1 At the end 1b, the rotational torque M becomes zero.

That is, at point A, where the wall thickness of the outer cylinder member 1 is relatively large, a large rotational torque M is received, while at a point where the wall thickness is smaller than point A, the rotational torque M is received.

/2, so the taper 13a formed on the outer cylinder member 1
Therefore, there is a risk that the strength of the outer cylinder member 1 will be insufficient.

In addition, the inner cylinder member 3a receives the rotational torque M, /2 by the elastic member 7 at the point A where the wall thickness is small, and receives the rotational torque M at the point where the wall thickness is large. The taper 15a formed on the inner cylindrical member 3a provides an effect that there is no fear that the strength of the inner cylindrical member 3a will be insufficient.

Effects of the Invention As is clear from the above explanation, according to the propeller shaft for a vehicle according to the present invention, it is possible to increase the thickness of the elastic member without changing the outer diameter of the propeller shaft itself. It is possible to widen the variable range of torsional rigidity of the shaft, and further improve vibration-proofing and sound-proofing properties. Further, since the propeller shaft itself is not enlarged, there is an effect that there is no possibility that the outer cylinder member will interfere with other members.

Further, according to the present invention, the rotational torque transmitted from the outer cylinder member to the inner cylinder member is such that a large rotational torque is transmitted through the elastic member at a relatively thick point of the outer cylinder member and the inner cylinder member. At the same time, a small rotational torque is transmitted through the elastic member at points where the wall thickness of the outer cylinder member and the inner cylinder member is relatively small, so that the inner cylinder member and the inner cylinder member are This exhibits a characteristic that the outer cylinder member is not accustomed to having insufficient strength.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of essential parts showing one embodiment of a propeller shaft for a vehicle according to the present invention, FIG. 2 is a schematic diagram showing the wheel action of the present invention, and FIG. 3 is a schematic diagram showing an example of a conventional propeller shaft. FIG. 1... Outer cylinder member, 1a... Inner wall surface, lb, lc...
・Both ends, 3a, 3b...inner cylinder member, 4a, 4b...
・Outer wall surface, 5... Space part, 7... Elastic member, 20.
...Propeller shaft, 13g, 13b, 15g, 15b--Taper.

Claims (1)

[Claims] (1) An outer cylindrical member having a predetermined length, an inner cylindrical member inserted coaxially from both ends of the outer cylindrical member toward the inside of the outer cylindrical member with a certain space, and a a substantially cylindrical elastic member that is fixed and whose upper surface presses against the inner circumferential surface of the outer cylinder member, and a plurality of the elastic members are arranged in series at predetermined intervals along the axial direction of the inner cylinder member. In the vehicle propeller shaft made of
A taper is provided to gradually reduce the wall thickness of the outer cylinder member from the inside to both ends, and the outer wall surface of the inner cylinder member inserted from both ends of the outer cylinder member is A taper is provided that gradually reduces the wall thickness of the inner cylinder member as it goes inward, and the elastic member is placed in a space formed between the taper on the outer cylinder member side and the taper on the inner cylinder member side. A vehicle propeller shaft characterized by being press-fitted and fixed.