JPH06101720A - Shaft coupling - Google Patents

Abstract

PURPOSE:To utilize a shaft coupling for connecting, for example, a propeller shaft for transmitting driving force of an engine, a steering shaft for transmitting torque of a steering wheel, or the like in the coupling used for a propulsion shaft and the like for connecting one shaft to the other shaft so as to transmit torque. CONSTITUTION:A disk-like coupling is interposed between a shaft end on a driving side and a shaft end on a driven side so as to transmit motive power. A plurality of cylinders 1 connected to a shaft on the driving side are arranged coaxially at equal intervals. Plural cylinders 2 connected to a shaft on the driven side are arranged coaxially at equal intervals and alternately with the cylinders 1. The cylinder 1, 2 are surrounded by rubber elastic members, where the adjacent rubber elastic members are connected to each other with synthetic resin disks. A spring constant of the rubber elastic member surrounding either of the cylinders 1 and 2 is larger than that of the rubber elastic member surrounding the other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft coupling used for a propulsion shaft or the like for connecting one shaft and the other shaft to transmit a rotational force, for example, transmitting a driving force of an engine. It can be used for connecting a propeller shaft and a steering shaft that transmits the rotational force of a steering wheel.

[0002]

2. Description of the Related Art Among conventional shaft couplings, there is a split type as shown in FIG. 9 as an example of a shaft coupling used for connecting a propeller shaft. In the figure, 11
(11 ₁ , 11 ₂ , 11 ₃ , ...) Are shaft joint bases, and in general, six bases are connected by connecting pins 12 to form a shaft joint. In this shaft joint, a tensile member 13, for example, an organic fiber bundle is wound between the two pins 12 and 12 so as to withstand the tension generated between the connecting pins 12 and 12 mounted in one base 11. Then, the whole is covered with the elastic rubber 14 to maintain elasticity.

However, in this type of shaft coupling,
Since the fiber cord 13 is wound in many layers, the cord tension varies among the layers, and the adhesiveness between the cords 13 and 13 and between the cord 13 and the elastic rubber 14 is not uniform. There is. This naturally means that there is a variation in the characteristics between the substrates, and these factors also cause variations in the heat shrinkage rate of the cord due to the action of heat in the rubber vulcanization process and the surface of the elastic rubber. It is supposed to have a great influence on the production and the performance such as the protrusion of the cord to the.

In order to solve these problems, the present inventor has
As shown in FIG. 10, a plurality of cylinders 21 connected to a drive-side shaft are arranged on a concentric circle at equal distances, and a plurality of cylinders 22 connected to a driven-side shaft are arranged on a concentric circle at equal distances. It is also arranged alternately with the tubular bodies 21, and each of the tubular bodies 21 and 22 is surrounded by a rubber elastic body 23, and a space between the adjacent rubber elastic bodies 23 and 23 is a synthetic resin board body 24. Provided a connected shaft coupling (Japanese Patent Application No. 2-414533)
issue).

This uses a single synthetic resin 24 as the base of the shaft coupling.
It is configured with, to improve the strength as a shaft coupling,
It aims to reduce the cost and weight of the shaft coupling, as well as simplifying the manufacturing, while reducing the variation in performance. That is, in the proposed invention, instead of the fiber cord, the synthetic resin 24 interposed between the tubular bodies 21 and 22 directly transmits the rotational torque, and the synthetic resin 24 pulls between the tubular bodies 21 and 22. Against the force, or the cylinder 22,
The torque is transmitted to the shaft on the driven side by resisting the compression force between the shafts 21, and the drawbacks of the conventional technique are greatly improved.

However, there is also a point in need of improvement in the present invention, which is that the synthetic resin 24 becomes a mass body as shown in FIG. 11, and the spring system is provided on both sides thereof, that is, the driving side and the driven side. Will be configured. That is, this means that when the mass of the synthetic resin 24, the natural frequency determined by the spring of the rubber elastic body 23, and the frequency of the vibration external force on the driving side match, a so-called resonance phenomenon occurs and the vibration from the driving side occurs. It becomes significantly large, which results in deterioration of the vibration isolation performance.

[0007]

DISCLOSURE OF THE INVENTION The present invention is intended to eliminate the resonance phenomenon caused by the synthetic resin portion and rubber in the already proposed shaft coupling.

[0008]

The structure of a shaft joint according to the present invention is a disc-shaped shaft joint mounted between a drive-side shaft end and a driven-side shaft end for transmitting power. A plurality of cylinders 1 connected to the shafts of the above are arranged on a concentric circle at equal distances, and a plurality of cylinders 2 connected to the driven side shaft are arranged on a concentric circle at the same distance, and The cylinders 1 and 2 are arranged alternately, and are surrounded by a rubber elastic body,
In a shaft coupling in which adjacent rubber elastic bodies are connected by a synthetic resin board, a rubber elastic body surrounding one of the cylinders 1 and 2 has a spring constant that surrounds the other cylinder. It is characterized in that it is made sufficiently larger than the spring constant of the elastic body. The spring ratio of the rubber elastic body surrounding the cylinders 1 and 2 is preferably 1: 6 or more.

As the synthetic resin used in the present invention, what is called an engineering plastic is mainly adopted, and among them, a polyamide resin is generally used. Needless to say, a composite system in which fibers such as glass and carbon are mixed with such plastic to improve strength may be used.

[0010]

As described above, in the invention of Japanese Patent Application No. 2-414533, the natural frequency determined by the mass of the synthetic resin 24 and the spring of the rubber elastic body 23, and the frequency of the vibration external force on the driving side are If they match, a resonance phenomenon may occur and the vibration isolation performance may deteriorate. The present invention seeks to remove such a resonance phenomenon from the range of frequencies substantially used.

Now, consider a simplified model in which the damping term is ignored. The mass y of the mass body is m, the spring constant of the rubber elastic body coupled to the driving side is k ₁ , the spring constant of the rubber elastic body coupled to the driven side is k ₂ , and the input vibration y is y _0.
= Sin ωt, the vibration transmission force F transmitted to the driven side
Is expressed by the following equation. F = k ₁ · k ₂ · y ₀ / (k ₁ + k ₂ ) −mω ^{2 Further} , the spring constant K of this system is K = k ₁ · k ₂ / (k ₁ +
k ₂ ), while the natural frequency ω _n is ω _n = {(k
₁ + k ₂ ) / m} ^0.5 . Now, assuming that k ₁ = k ₂ in the already proposed shaft coupling, the spring constant K = k of this system
_1/2, at this time, the natural frequency _{ω n, ω n = (2k} 1 /
m) ^0.5 .

On the other hand, in the shaft coupling of the present invention, k ₂ ′ =
Assuming α · k ₁ ′, the spring constant K ′ of this system is K ′ =
(Α / 1 + α) · k ₁ ′. Here, 'when such a, k _1' K = K a = (1 + α) / 2α · k 1, k 2 '= (1 + α) / 2 · k 1. Therefore, the resonance point of the proposed shaft coupling, ω = (2k
The transmission force F of the shaft joint of the present invention at ₁ / m) ^0.5 is as follows. _{F = k 1 '· k 2} ' · y 0 / (k 1 '+ k 2') -mω 2 = (α + 1) 2/2 (α-1) 2 · k 1 · y 0

If the resonance magnification F / k ₁ · y ₀ <1, then α> 3 + √8 is obtained. That is, if the spring ratio of k ₁ ′ and k ₂ ′ is 3 + √8 or more, the resonance point ω =
At (2k ₁ / m) ^0.5 , the resonance magnification of the shaft coupling of the present invention is 1 or less.

Since the present invention employs the above-mentioned structure, the synthetic resin interposed between the cylinders 1 and 2 directly transmits the rotational torque in place of the fiber cord, and this synthetic resin is used between the cylinders. The torque is transmitted to the driven side shaft by resisting the pulling force of the cylinder or the compressive force between the cylinders. Especially, by taking the spring ratio of the rubber elastic body to be extremely large, the natural frequency can be increased without changing the spring constant of the product, and it is possible to obtain a high natural frequency within the range of the normal shaft coupling operating frequency. It is possible to avoid the resonance and enhance the anti-vibration effect.

[0015]

SPECIFIC EXAMPLES The shaft coupling of the present invention will be described in more detail with reference to the drawings. 1 is a front view showing a first embodiment of a shaft coupling of the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG.
Is a cross-sectional view taken along line BB. In the figure, reference numeral 1 is a cylinder connected to the drive-side shaft, and 2 is a cylinder connected to the driven-side shaft. Each of the cylindrical body 1 and the cylindrical body 2 is generally provided concentrically with each other, and a yoke (not shown) extending from each axis is provided.
Corresponding to, and these are arranged alternately. These cylinders 1 and 2 can be arranged on different concentric circles depending on the case.

Reference numerals 3 and 4 denote these cylindrical bodies 1 and 2.
It is a rubber elastic body that surrounds the entire circumference of, and absorbs vibrations during rotation and buffers against sudden loads.
Further, it is provided to reduce noise. In this rubber elastic body 3, a currant 5 is formed in the rotational circumferential direction. The currant 5 serves to make the spring ratios of the rubber elastic bodies 3 and 4 different from each other, whereby the resonance point is displaced. By the way, the spring constants of the rubber elastic body 3 and the rubber elastic body 4 in the direction perpendicular to the axis are respectively 180
kg / mm and 20 kg / mm, spring ratio 9: 1
Has become.

Reference numeral 6 is a synthetic resin disc body in which these rubber elastic bodies 3 and 4 surrounding the cylindrical bodies 1 and 2 are arranged at predetermined positions to make them independent of each other, and a disc-shaped nylon resin is used. ing.

The synthetic resin board 6 has a function of setting the respective cylinders 1 and 2 at predetermined positions, and, when used in rotation, the cylinder 1 connected to the drive side shaft and the driven side. It has a function of transmitting a tensile force between the cylindrical bodies 2 connected to the shaft, and has a function of a tensile body in a conventional shaft coupling.

In this case, first, the rubber elastic bodies 3 and 4 are integrated around the cylindrical bodies 1 and 2 by vulcanization and adhesion, and these are set in a position for forming a disc body, and then synthetic resin is injection-molded. It is general that the respective elements are integrated by a means for forming a rubber elastic body in which the synthetic resin board 6 is formed first and the above-mentioned cylinders 1 and 2 are enclosed in the holes 7 provided therein. It is also possible to press fit 3 and 4. In this example, the outer circumferences of the rubber elastic bodies 3 and 4 and the holes 7 of the synthetic resin board 5 are in contact with each other in a perfect circular shape, but the contact surfaces of the two do not necessarily have to be perfect circles. .

FIG. 4 is a front view of the second embodiment of the present invention, in which the holes 7 and 8 provided in the board 6 are alternately made different, and the rubber elasticity fitted into the holes 7 and 8 is shown. The spring ratio of the rubber elastic body is changed by changing the shapes of the bodies 3 and 4.

FIG. 5 is a front view of the third embodiment of the present invention, in which the holes 7 and 8 provided in the board 6 are the same, but the rubber elasticity which fits into these holes 7 and 8 is used. An interring 9 is vulcanized and bonded to the body 4 to change the spring ratio of the rubber elastic body.

FIG. 6 is a front view of the fourth embodiment of the present invention, and FIG. 7 is a sectional view taken along the line CC. The structure of this shaft joint is basically the same as that of the shaft joint shown in FIG. 4, but in the cylindrical body 2, a bulge portion 10 is provided at the center of the cylindrical body 2 to increase the spring ratio of the rubber elastic body. It has been changed. Incidentally, in the present invention, it is also possible to prevent the rubber body from coming off from the inside by giving such a bulge portion to the cylindrical bodies 1 and 2.

FIG. 8 is a front view showing the fifth embodiment of the present invention. In this example, the rubber elastic body 4 surrounding the cylindrical body 2 is completely surrounded by the synthetic resin board 6. This is an example that has not been done. In this way, the spring ratio can be changed by changing the shapes of the rubber elastic bodies 3 and 4.

Although the embodiment of the present invention has been described above focusing on the change in the shape of the rubber elastic bodies 3 and 4, the change in the hardness of the rubber may be taken into consideration. Of course, even if the shapes are the same, the object can be achieved by changing the hardness.

[0025]

According to the present invention, the synthetic resin board receives the tension (or compression) applied between the cylinders, which is formed by winding a conventional fiber cord many times. Since it is a single material rather than a stretcher, it can achieve higher precision, and because it is a resin material compared to rubber, it has strength against contact with flying objects, etc. It is possible to select a strong material and improve durability.

In particular, the present invention seeks to remove such a resonance phenomenon from the range of substantially used frequencies. This means that by taking an extremely large spring ratio of the rubber elastic body used, it is possible to obtain a high natural frequency with almost no change in the spring constant of the product. Avoid,
It is possible to enhance the vibration damping effect.

The shaft coupling of the present invention has a relatively high rigidity against rotational torque, and is preferable when the rigidity in other directions is low,
For example, it is suitable for a joint between a drive side yoke and a propeller shaft or a propeller shaft and a differential side for an automobile.

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of a shaft coupling of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a front view showing a second embodiment of the shaft coupling of the present invention.

FIG. 5 is a front view showing a third embodiment of the shaft coupling of the present invention.

FIG. 6 is a front view showing a fourth embodiment of the shaft coupling of the present invention.

7 is a cross-sectional view taken along the line CC of FIG.

FIG. 8 is a front view showing a fifth embodiment of the shaft coupling of the present invention.

FIG. 9 is a front view of a conventional shaft coupling.

FIG. 10 is a front view of an already proposed shaft coupling.

[Explanation of symbols]

 1, 2 ... Cylindrical body, 3, 4 ... Rubber elastic body, 5 ... Currant, 6 ... Synthetic resin board, 7, 8 ... Holes provided in the synthetic resin board, 9 ... Ring, 10 ... A bulge in the center of the cylinder.

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[Procedure amendment]

[Submission date] March 27, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Brief description of the drawing

[Correction method] Change

[Correction content]

[Brief description of drawings]

FIG. 1 is a front view showing a first embodiment of a shaft coupling of the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a sectional view taken along line BB of FIG.

FIG. 4 is a front view showing a second embodiment of the shaft coupling of the present invention.

FIG. 5 is a front view showing a third embodiment of the shaft coupling of the present invention.

FIG. 6 is a front view showing a fourth embodiment of the shaft coupling of the present invention.

7 is a cross-sectional view taken along the line CC of FIG.

FIG. 8 is a front view showing a fifth embodiment of the shaft coupling of the present invention.

FIG. 9 is a front view of a conventional shaft coupling.

FIG. 10 is a front view of an already proposed shaft coupling.

FIG. 11 is a conceptual diagram showing a spring system of an already proposed shaft coupling.

[Explanation of reference symbols] 1, 2 ... Cylindrical body, 3, 4 ... Rubber elastic body, 5 ... Currant, 6 ... Synthetic resin board, 7, 8 ... Holes provided in the synthetic resin board, 9 ... Interring, 10 ... Swelling part in the center of the cylinder.

Claims (2)

[Claims] 1. A disc-shaped shaft coupling mounted between a drive-side shaft end and a driven-side shaft end for transmitting power, wherein a plurality of cylindrical bodies 1 connected to the drive-side shaft are concentric. A plurality of cylinders 2 which are arranged equidistantly above and are connected to the driven shaft.
Are equidistantly arranged on a concentric circle and are arranged alternately with the cylinders 1, the cylinders 1 and 2 are surrounded by a rubber elastic body, and the adjacent rubber elastic bodies are made of a synthetic resin board. In the shaft coupling connected by, the spring constant of the rubber elastic body surrounding either the cylinder 1 or the cylinder 2 is sufficiently larger than the spring constant of the rubber elastic body surrounding the cylinder on the other side. And shaft coupling. 2. The shaft coupling according to claim 1, wherein a rubber elastic body surrounding the cylindrical bodies 1 and 2 has a spring ratio of 1: 6 or more.