JPH07269582A - Elastic shaft coupling - Google Patents

Abstract

PURPOSE:To reduce the vibration noise and to improve the durability of a rubber elastic body as well as to exercise a twisting spring property from a low scope to a high scope. CONSTITUTION:An elastic shaft joint F.J is composed of a cylindrical vibration- proof body 1 formed by providing a rubber elastic body 4 which was contracted preliminarily by a drawing and fixing process, between an inner tube 2 and an outer tube 3; and a blacket 6 to which the vibration-proof body 1 is fitted. And a projection form stopper 5 fitting to at least one blacket 6 is formed to the inner tube 2, while a recess form fixing part 8 corresponding to the projection form stopper 5 is formed to the blacket 6, the cylindrical vibration- proof body 1 is pressed in and fitted in the blacket 6, and a clearance is formed between the projection form stopper 5 and the recess form fixing part 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an elastic shaft joint mainly for automobiles, and more particularly to an elastic shaft joint used for low rigidity.

[0002]

2. Description of the Related Art Conventionally, various attempts have been made as this type of shaft coupling, but for example, as shown in FIG. 12, an elastic shaft coupling 31 is provided between an inner cylinder 32 and an outer cylinder 33. A rubber elastic body 34 is interposed and fixed, and a flange 36 having a bolt hole 35 is integrated with the outer cylinder 33, and is bolted to a rotating shaft. On the other hand, a shaft 37 is connected to the inner cylinder 32, and this is fixed by a key 38.

Further, as shown in FIG. 13 which is a sectional view taken along the line II-II in FIG. 12, a tooth-shaped convex strip 32 'is formed on the outer peripheral surface of the inner cylinder 32 in the axial direction. Correspondingly, tooth-shaped convex strips 33 'are similarly formed on the inner peripheral surface of the outer cylinder 33, and an annular rubber elastic body 34 cushions the gap between the two 32' and 33 '. A trial of an elastic shaft coupling which is directly fitted and mounted as means (Japanese Patent Laid-Open No. 62-2832).
No. 18) (hereinafter referred to as "A invention technology"). Further, as shown in FIG. 14, there is an elastic shaft coupling in which an elastic rubber bush 34 is interposed and fixed between the inner cylinder 32 and the outer cylinder 33. At this time, the rubber bush 34 is inserted through the insertion hole 39 in the axial direction.
And a bulging portion 40 is formed in the insertion hole disposing portion provided in the outer cylinder, and a rubber stopper 41 is fixedly disposed on the protruding portion, while the rubber stopper 4 is provided in the insertion hole 39.
An attempt was made for a shaft coupling having a structure in which a spacer 42 made of a plastic harder than No. 1 is fitted and inserted, and a slight gap 43 is formed on the inner wall surface of the spacer 42 and the rubber bush 34 (JP-A-61- No. 201924) (hereinafter "B invention technology")
Say. ) Etc.

[0004]

However, in such a conventional elastic shaft coupling, the former has a structure in which rubber is vulcanized and adhered between a deformed outer cylinder and a corresponding inner cylinder and vibrates. Since the rubber elastic body as an absorber carries both the low and high load regions, wear loss is rapid and becomes a problem in terms of durability. In the latter case, the elastic body has a different shape and is easily damaged. That is, in the above-mentioned invention A, as shown in FIG. 13, the rubber elastic body 34 is fixed between the inner and outer cylinders between the protrusions 32 'and 33', so that The rotation torque is entirely carried by the rubber elastic body 34. Further, in the above-mentioned invention B technique, as shown in FIG. 14, a spacer made of hard plastic is inserted between the inner cylinder and the outer cylinder, and the outer cylinder 33 is A rubber stopper 41 is fixed to the inner surface of the bulging portion 40, and a rubber bush 34 is fixed to the inner cylinder 32 and the outer cylinder 33. Therefore, the rubber bush 34 acts in the low load range. Further, in the high load region, the rubber stopper 41 and the spacer 42 on the outer surface of the bulging portion 40 of the outer cylinder 33 act, but the rubber bush 34 has a different cross-section for inserting the spacer 42. The insertion port 39 is formed Since it is, the rubber elastic body had problems on again durability becomes to have a different shaped cross-section.

In view of the above situation, the present inventor has conducted extensive studies on the structure of a rubber elastic body, which is a drawback of the conventional elastic joint, and as a result, firstly, as a result, firstly, between the inner cylinder and the outer cylinder. The rubber elastic body is compressed and disposed in the inner cylinder, and the inner cylinder is provided with a convex portion for engaging with the flange in advance to form an inner cylinder / outer cylinder assembly. This is carried on the corner, and then the assembly is fitted and fixed to a flange having a concave portion which engages with the convex portion of the inner cylinder in advance. By exerting its function, by supporting the torsion angle in the high frequency range, a non-linear spring characteristic is obtained, and moreover, the axial center of the rubber elastic body and the torsion center ring of the shaft joint are made to coincide with each other. This ensures smooth torque transmission. Allowed to be possible to improve the durability of the rubber elastic body is led to the finding of the fact that reduced.

Thus, the present invention was made on the basis of the above-mentioned findings, and the object thereof is that the main body of the rubber elastic body and the stopper portion can be configured separately while having a simple structure. In addition to exhibiting torsional spring characteristics ranging from the low range to the high range, the vibration noise is reduced and the durability of the rubber elastic body is improved.

[0007]

That is, the feature of the elastic shaft coupling of the present invention which meets the above object is that a rubber elastic body is drawn between an inner cylinder and an outer cylinder in a direction perpendicular to the axial direction. A cylindrical vibration isolator, which is pre-compressed and fixed in place, and an elastic shaft joint comprising a bukerat for fitting the cylindrical vibration isolator,
A convex stopper portion that engages with at least one of the brackets is formed on an inner cylinder forming the cylindrical vibration isolator,
A concave fixing portion corresponding to the convex stopper portion is formed on the bracket, and the cylindrical vibration isolator is press-fitted into the bracket so as to be freely rotatable, and the convex stopper portion and the concave This is a configuration in which there is a gap between the fixed portion and the fixed portion.

Further, it is preferable that the axial center of the rubber elastic body of the cylindrical vibration isolator and the torsion center ring of the elastic shaft joint are aligned. Furthermore, the rubber elastic body,
It is more preferable to form a plurality of slits in the axial direction.

[0009]

The elastic shaft coupling of the present invention having the above-mentioned structure has a function of transmitting a rotational torque by free rotation, and a rubber elastic body that acts on a torsion torque in a low range,
The elastic shaft coupling is easy to assemble because the stopper part that acts on the torsion torque in the high frequency range is separately configured, and the elastic body described above is effective for the torsion torque of the low frequency range. Since it will be carried, and for the torsional torque in the high range adjacent to this, a gap is made to exist between the convex stopper portion of the inner cylinder and the concave fixing portion of the bracket. The convex stopper portion directly connected to the inner cylinder comes into contact with the concave fixing portion of the bracket to exert a torsion spring characteristic in a high range. Further, as described above, the torsional torque of the rubber elastic body can be controlled to be low, so that the rubber elastic body and the stopper portion share the so-called non-linear characteristic which is naturally shared by the low to high range of the load torque. In addition, the durability of the rubber elastic body can be ensured, and even if the elastic body is broken, the inner cylinder / bracket exhibits a stopper function, so that there is no problem in load transmission. Moreover, since the cylindrical vibration isolator, which is a combination of the inner cylinder, the outer cylinder, and the rubber elastic body, is an independent body, it can be simply press-fitted into the bracket and can be easily assembled. Is also easy.

[0010]

Embodiments of the elastic shaft coupling of the present invention will be described below with reference to the accompanying drawings, but it goes without saying that the present invention is not limited thereto.

1 to 5 show a first embodiment of the present invention. In the figure, reference numeral 1 denotes a cylindrical vibration isolator, in which a rubber elastic body 4 is pre-compressed and vulcanized and bonded between the inner cylinder 2 and the outer cylinder 3 at a right angle to the axial direction of the inner cylinder 2. Further, the inner cylinder 2 is formed with at least one convex stopper portion 5 protruding at right angles to the axial direction. As for the formation position of the convex stopper portion 5, when the cylindrical vibration isolator 1 is fitted to the bracket 6, it is formed on the L-shaped flange 7 side of the end portion of the bracket 6 as shown in FIG. Alternatively, FIG.
As shown in Fig. 5, the positioning on whether to form it on the opposite end or further on the center is arbitrary, but the convex shape provided on the bracket 6 into which the cylindrical vibration isolator 1 is fitted It is determined in relation to the positioning of the concave fixing portion 8 corresponding to the stopper portion 5. The number of the convex stopper portions 5 and the concave fixing portions 8 is at least one, and in order to absorb the vibrations corresponding to the torsional load as the elastic joint and maintain the smooth rotation, 3 to 5 are suitable. Further, the rubber elastic body interposed between the inner cylinder 2 and the outer cylinder 3 does not need to be formed along the entire outer cylinder peripheral surface of the inner cylinder 2, and the shaft between the inner cylinder 2 and the outer cylinder 3 is not required. In order to cope with the torsion torque in the direction orthogonal to the direction, it is achieved by forming the slit 9 in the axial direction. Although the number of the slits 9 is arbitrarily selected, it is naturally determined depending on the sizes of the inner cylinder 2 and the outer cylinder 3, the thickness of the rubber elastic body 4, the magnitude of the load, the type, and the like. When the slits 9 are formed between the respective convex stopper portions 5 as shown in FIG. 5, the rubber elastic body 4 will carry this evenly with respect to the torsion torque. The rubber elastic body used in the present invention is a natural rubber,
Styrene-butadiene copolymer rubber, polybutadiene rubber, polyisoprene rubber, neoprene rubber and the like are used, but natural rubber is particularly preferable.

By the way, as shown in FIGS. 3 and 4, the cylindrical vibration isolator 1 is formed by elastically fitting an F. Although J is configured, it is necessary for the convex stopper portion 5 of the inner cylinder 2 and the concave fixing portion 8 formed in the bracket 6 to maintain the gap 10 in the press-fitted state. As a result, the rubber elastic body 4 carries the load with respect to the twisting torque in the low range, and the convex stopper portion 5 carries the load with respect to the twisting torque in the high range. In this example, the elastic shaft coupling F. An example is shown in which the torsion centering P of J and the axial center P ′ of the rubber elastic body 4 are made to coincide with each other.
Both centers P, with respect to torsion against torque load accompanying rotation,
Matching P'is preferable because a smooth torsion spring characteristic and a soft torsion spring can be obtained softly.

FIGS. 6 to 8 show a second embodiment of the present invention. In this example, the position of the convex stopper portion 5 provided on the inner cylinder 2 is provided on the flange 7 side. , The elastic shaft coupling F. This is an example in which the torsion centering P of J and the axial center P ′ of the rubber elastic body 4 are matched. Further, FIG. 9 further shows a third embodiment of the present invention.
Similar to the cylindrical vibration isolator 1 shown in FIG. 6, this is an example in which the position of the convex stopper portion 5 provided on the inner cylinder 2 is provided on the flange 7 side. However, the elastic shaft coupling F. This is an example in which the torsion centering P of J and the axial center P ′ of the rubber elastic body 4 do not coincide.

Next, the elastic shaft coupling F. The function of J will be described.

The elastic shaft coupling F. J has a rubber elastic body interposed and fixed between the inner cylinder 2 and the outer cylinder 3 for transmitting the rotational torque, and further has a convex stopper portion 5 on the inner cylinder. It is formed by press-fitting and fitting into a bracket 6 having a concave fixing portion 8 that can be fitted, and is rotated and transmitted to another by a flange 7 provided on the bracket 6. Here, for torsional torque in a low range, As for the rubber elastic body 4, the rubber elastic body 4 supports the rubber elastic body 4, and further, with respect to the torsional torque in the high range adjacent thereto, the convex stopper portion 5 and the concave fixing portion 8 on the bracket 6 which fits are stoppers. Exert function. As a result, this elastic shaft coupling F. J exhibits a non-linear characteristic as shown in FIG.
That is, two types of linear torsion spring characteristics having different torsion spring constants are continuous, and a non-linear characteristic having forward and reverse symmetry is obtained. Further, in terms of durability, as compared with the conventional elastic shaft joint, as shown in FIG. 11, in the elastic shaft joint (a) of the present invention, the conventional elastic shaft joint (b) has the rubber elastic body main body and the stopper. The rubber elastic body body and the stopper portion are separated from each other, while the rubber elastic body is sharply lowered in durability because it bears a high-range torsional torque by directly contacting with the rubber portion. Therefore, when the load torque is input, the load on the rubber elastic body is reduced and the carrying rate is kept small, which is excellent in durability.

Since the elastic shaft coupling according to the present invention is mainly applied for low loads, for example, the rotational drive of the rear engine of an automobile is used for the rotational force transmission shaft of a front air cooling fan, a dynamo, an air conditioner or the like. Used as a joint.

[0017]

As described above, according to the present invention, the cylindrical vibration isolator in which the rubber elastic body is pre-compressed and fixed by the drawing process in the direction perpendicular to the axial direction between the inner cylinder and the outer cylinder. And an elastic shaft coupling made of Bukerat which fits the cylindrical vibration isolator, first, an assembly of an inner cylinder having a convex stopper function and an outer cylinder as a constitution of the cylindrical vibration isolator, and then, With a structure in which the cylindrical vibration isolator is press-fitted into the bracket,
Further, since a concave fixing portion corresponding to the convex stopper portion is formed in this bracket so that a gap exists between them, and the rubber elastic body and the stopper portion are separated from each other, it is like a conventional elastic joint. The durability of the rubber elastic body can be ensured as compared with a structure in which the rubber elastic body and the stopper portion are in direct contact with each other, and the rubber elastic body carries this in the low load region of the torsion torque, while For the load range, the stopper portion comes into contact with the concave portion of the bracket and carries it. That is, since the inner cylinder convex portion functions as a low-range spring until it comes into contact with the concave portion of the bracket, and after it comes into contact with it, it functions as a high-range spring. It acts over a wide range and functions smoothly, and it is possible to reduce vibration noise and improve durability.

[Brief description of drawings]

FIG. 1 is a front view of a cylindrical vibration isolator according to a first embodiment of the present invention.

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

FIG. 3 is a front view of the elastic shaft coupling showing a state where the cylindrical vibration isolator shown in FIG. 1 is fitted in a bracket.

FIG. 4 is a sectional view taken along line BB of FIG.

FIG. 5 is a bottom view of the elastic shaft coupling shown in FIG.

FIG. 6 is a front view of another cylindrical vibration isolator of the present invention, showing the second embodiment of the present invention.

7 is a bottom view of the elastic shaft coupling showing a state where the cylindrical vibration isolator shown in FIG. 6 is fitted in a bracket.

8 is a cross-sectional view taken along the line DD of FIG.

FIG. 9 is a longitudinal sectional view of an elastic shaft coupling showing a third embodiment of the present invention and showing a state in which another cylindrical vibration isolator of the present invention is fitted in a bracket.

FIG. 10 is a torsion spring characteristic diagram of an elastic shaft coupling according to the present invention and a conventional elastic shaft coupling.

FIG. 11 is an input torque-repetition number diagram comparing the durability of the elastic shaft coupling according to the present invention and the conventional elastic shaft coupling.

FIG. 12 is a vertical sectional view of a conventional elastic shaft coupling.

13 is a sectional view taken along line II-II of FIG.

FIG. 14 is a cross-sectional view showing another example of a conventional elastic shaft coupling.

[Explanation of symbols]

 1 Cylindrical Vibration Isolator 2 Inner Cylinder 3 Outer Cylinder 4 Rubber Elastic Body 5 Convex Stopper 6 Bracket 7 Flange 8 Concave Fixing Part 9 Slit 10 Gap 11 Bolt Hole F. J elastic shaft coupling

Claims (3)

[Claims] 1. A cylindrical vibration isolator in which a rubber elastic body is precompressed and fixed between an inner cylinder and an outer cylinder by drawing in a direction perpendicular to the axial direction, and the cylindrical vibration isolator. In the elastic shaft coupling made of Bukerat which fits, a convex stopper portion that engages with at least one of the brackets is formed in the inner cylinder forming the cylindrical vibration isolator, and the bracket has the convex A concave fixing portion corresponding to the stopper portion is formed, and the cylindrical vibration isolator is press-fitted into the bracket so as to be freely rotatable, and a gap is provided between the convex stopper portion and the concave fixing portion. An elastic shaft coupling characterized by the presence of. 2. The elastic shaft joint according to claim 1, wherein an axial center of the rubber elastic body of the cylindrical vibration isolator and a torsion center ring of the elastic shaft joint are made to coincide with each other. 3. The rubber elastic body has a plurality of slits formed in the axial direction.
The elastic shaft coupling described.