JP3384575B2 - Sliding bush - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding bush used for a rotary support portion such as a swing arm of a vehicle suspension device, and more particularly to a riding comfort and steering. It is intended to improve both the performance and the stability. 2. Description of the Related Art In order to improve the ride comfort of an occupant in a vehicle, the mounting portion (rotation support portion) of the suspension arm is elastically supported, and when the vehicle gets over a bump on a road surface or the like. In order for the suspension arm to be able to smoothly rotate, the rotation support portion needs to be rotatably supported with little frictional resistance. Further, from the viewpoint of the steering stability of the vehicle, the mounting portion of the suspension arm needs to be mounted in a state of high rigidity in the front-rear direction of the vehicle. With these things in mind,
A conventional suspension arm mounting portion (rotation support portion) is provided with a sliding bush as shown in FIG. However, this has an inner cylinder 20 and an outer cylinder 30 made of metal, has an anti-vibration rubber 50 between them, and has a relative sliding motion (rotational motion) between the inner cylinder 20 and the inner cylinder 20. And a backup sleeve 80 for reinforcing the insert 40. And
Further, between the inner cylinder 20 and the insert 40, a minute play (G) is provided for smooth sliding movement, and the minute play (G) is filled with grease or the like as lubricating oil. It has a configuration that is In order to prevent the leakage of the lubricating oil, a seal member including an oil seal 70 and a seal ring 60 is provided at both ends of the inner cylinder 20. Therefore, this not only increases the number of components,
The structure becomes complicated, and there is a problem in terms of productivity and durability. [0004] In order to solve these problems, a dry type which does not use a lubricating oil as shown in FIG. 3 can be considered. This has a large-diameter portion 2 having an outer diameter larger than both ends at the center of the inner cylinder 20.
10, while the vibration-proof rubber 50 joined to the outer cylinder 30 is provided.
Is provided with a fiber layer 40 having a low coefficient of friction in a portion that comes into sliding contact with the inner cylinder 20.
Therefore, in this case, a relative rotational motion between the inner cylinder 20 and the outer cylinder 30 is obtained by a sliding motion between the outer peripheral surface of the inner cylinder 20 and the fiber layer 40. On the other hand, a thrust force generated between the inner cylinder 20 and the outer cylinder 30 is provided integrally with the bulging portion formed by the large-diameter portion 210 and along the bulging portion. Between the fiber layer 40 and the vibration-proof rubber 50. However, in this case, when the thrust force has a large value, the large diameter portion 210 and the vibration isolating rubber 50
There is a danger that it will not be possible to carry it alone. As a result, there is a problem that the inner cylinder 20 comes out of the sliding bush under a high thrust force. Further, there is a problem in that the sliding portion such as the fiber layer 40 is worn by repeated operation (rotational sliding) under a high load, thereby causing play in the radial direction. SUMMARY OF THE INVENTION It is an object (problem) of the present invention to solve these problems, to provide a sliding bush for a suspension arm which is excellent in both ride comfort and steering stability and has a small number of parts. is there. [0005] In order to solve the above problems, the present invention takes the following measures. That is, it has an outer cylinder and an inner cylinder that are capable of relative rotational movement, and is located between the outer cylinder and the inner cylinder, is integrally joined to the outer cylinder, and is capable of sliding with the inner cylinder. In the sliding bush having the vibration-isolating rubber provided in the center portion of the inner cylinder, a large-diameter portion or a bulging portion having an outer diameter larger than the end portion is provided, while the inner periphery of the vibration-isolating rubber is provided. On the surface side, on the inner cylinder side
Mark) As the fiber comes, and the rubber
Two woven so that polyester fiber with good bondability comes
The fibrous layer of heavy woven structures provided above vibration damping rubber integrally, further
On the outside of such a fiber layer, a plastic insert is provided along the large-diameter portion or the bulging portion of the inner cylinder, and is bonded to the vibration-proof rubber and the fiber layer,
Further, so as to cover the small diameter portion formed in the vicinity of both ends of the inner cylinder, it was decided to adopt a configuration in which a so that providing the sealing rubber portion by extending the portion of the vibration damping rubber. According to the present invention, both the ride comfort and the steering stability are satisfied in the present invention. That is, in FIG. 1, the force (vibration) in the P direction is absorbed and attenuated by the vibration isolating rubber 5 provided between the outer cylinder 3 and the inner cylinder 2, and the force from the outer cylinder 3 side is reduced. It is not transmitted to the cylinder 2 side. Therefore, the vibration and the like are not transmitted to the vehicle body. On the other hand, when the wheel gets over a large bump or the like, a rotational motion (swing) of a large displacement angle of the suspension arm is generated based on the vertical movement of the wheel. Processing is performed by a smooth sliding motion between the cylinder 2 and the fiber layer 4 provided on the inner peripheral surface of the vibration-proof rubber 5. Accordingly, no force (vibration) is transmitted from the outer cylinder 3 side on which the suspension arm is mounted to the inner cylinder 2 side mounted on the vehicle body, and pitching and bouncing of the vehicle body are not caused. From these facts, good ride comfort can be obtained in a vehicle employing the present sliding bush. Next, with respect to the load (T) of the sliding bush in the thrust direction, the plastic insert 1 provided along the large diameter portion 21 of the inner cylinder 2 basically has the above-mentioned thrust load (T). T). That is, while the load (T) in the thrust direction is a small value, force and vibration, etc., due to the shear deformation of the vibration isolating rubber 5 provided between the outer cylinder 3 and the plastic insert 1 are kept. Is absorbed. On the other hand, when the thrust load (T) becomes a large value, the plastic insert 1 formed along the large diameter portion 21 of the inner cylinder 2 receives the thrust load (T). With this, the relative displacement between the outer cylinder 3 and the inner cylinder 2 is suppressed. This also prevents the inner cylinder 2 from slipping out of the sliding bush. As a result, the mounting rigidity in the thrust direction is increased, and the steering stability is also enhanced. [0008] Also, with respect to the twisting movement of the inner cylinder 2, since the fiber layer 4 having good slipperiness is provided so as to surround the large diameter portion 21, the deformation of the vibration-proof rubber 5 is merely achieved. Unlike what is dealt with, it will exhibit better followability. As a result, the followability of the suspension arm is improved, and the riding comfort is improved. With respect to this point, as shown in FIG. 2, when the bulging portion 21 ′ provided at the center of the inner cylinder 2 is formed into a spherical shape, a function similar to a so-called ball joint is exhibited. Thus, better ride comfort and steering stability can be obtained. In the present sliding bush, a part of the vibration isolating rubber 5 is extended to form a sealing rubber part 51, and the small diameter parts 22 formed at both ends of the inner cylinder 2 are formed by the sealing rubber part 51. Since the fiber layer 4 is in sliding contact with the outer surface of the inner cylinder 2 so as to cover the fiber layer 4, the seal between the fiber layer 4 and the outer surface of the inner cylinder 2 is sealed. It will be performed reliably. As a result, it is not necessary to separately provide a seal member as in the conventional one, and the tension force of the seal rubber portion 51 causes
The outer peripheral surface of the inner cylinder 2 is reliably sealed, earth and sand and rainwater are prevented from entering, and wear of the sliding surface can be prevented. A first embodiment of the present invention will be described with reference to FIG. The configuration of the present embodiment includes an inner cylinder 2 having a large-diameter portion 21 having a larger outer diameter than both ends in a central portion, and an outer cylinder 3 provided so as to be capable of rotating relative to the inner cylinder 2. When,
Between the inner cylinder 2 and the outer cylinder 3, the outer cylinder 3 side is integrally joined, and the inner cylinder 2 side is a sliding bush made of an anti-vibration rubber 5 or the like provided so as to be capable of sliding motion. Is basically formed. In such a basic configuration, a fiber layer 4 is provided on the inner peripheral surface side of the vibration-proof rubber 5 so as to be integral with the vibration-proof rubber 5 along the outer peripheral surface of the inner cylinder 2. I have.
The fiber layer 4 has, for example, a double woven structure of Teflon fibers and polyester fibers, and has Teflon fibers on one side and polyester fibers on the other side. It is woven. Such a fiber layer 4 is installed such that Teflon fiber having good slipperiness comes to the inner cylinder 2 side and polyester fiber having good bonding property to rubber comes to the vibration isolating rubber 5 side. You. Further, the inner cylinder 2 is provided outside the fiber layer 4.
The plastic insert 1 is provided along the large-diameter portion 21 and joined to both the vibration-proof rubber 5 and the fiber layer 4. here,
The plastic insert 1 is made of ultra-high molecular weight polyethylene, polyamide resin (nylon), or the like. In addition, in the case of the ultra-high molecular weight polyethylene, the bonding with the vibration isolating rubber 5 is performed by fusing simultaneously with molding by heat, pressure, and the like when molding the vibration isolating rubber 5. In such a case, it is performed by separately bonding with an adhesive. The above plastic insert 1
In the state of the material, as shown by the two-dot chain line in FIG. 1, it is made of a straight pipe, and is attached to the outside of the fiber layer 4 provided outside the inner cylinder 2. It is installed in a mold and then integrally molded when the vibration-proof rubber 5 is injection-molded. That is,
Since the plastic insert 1 is made of a material having a low melting point and low fluidity, it is deformed by heat and pressure during rubber molding, and at this time, the large-diameter portion 21 provided in the inner cylinder 2 is used. Along the large diameter portion 21
Will be automatically formed into a shape that wraps around. Further, a configuration is adopted in which a part of the vibration-proof rubber 5 is extended and a seal rubber portion 51 is provided so as to cover the small-diameter portions 22 provided near both ends of the inner cylinder 2. I have to do that. The sealing rubber portion 51 is formed of the same rubber material when forming the anti-vibration rubber 5.
And, it is integrally formed so as to wrap the fiber layer 4 provided outside the inner cylinder 2. Therefore, when the sliding bush itself is cooled after the molding, the vibration isolating rubber 5
In addition, a portion made of a rubber material such as the seal rubber portion 51 contracts by cooling. Along with this contraction, the portion of the seal rubber portion 51 also contracts, and a tension force is maintained between the seal rubber portion 51 and the small-diameter portion 22 of the inner cylinder 2. As a result, the sealing performance is improved. Next, the operation of the present embodiment having the above configuration will be described. When a vibration (shock) due to, for example, getting over a small bump of a wheel is transmitted to the suspension arm on which the sliding bush is attached, the force (vibration) is applied to the load (vibration) in the P direction in FIG. Conveyed as. However, the force (vibration) in the P direction is absorbed and attenuated by the vibration isolating rubber 5 provided between the outer cylinder 3 and the inner cylinder 2, and is attenuated from the outer cylinder 3 side to the inner cylinder 2 side. Is not transmitted to Therefore, the vibration and the like are not transmitted to the vehicle body. In addition, when the wheel gets over a large bump or the like, a rotational motion (swing) of the suspension arm based on the vertical movement of the wheel occurs,
This swing motion is processed by a smooth sliding motion between the inner cylinder 2 and the fiber layer 4 provided on the inner peripheral surface of the vibration-proof rubber 5. Therefore, no force (vibration) is transmitted from the outer cylinder 3 on which the suspension arm is mounted to the inner cylinder 2 on the vehicle body side, and pitching and bouncing of the vehicle body are not caused. From these facts, by the action of the sliding bush, good ride comfort can be obtained in a vehicle employing the present sliding bush. Next, with respect to the load (T) in the thrust direction of the sliding bush that affects the steering stability, the plastic insert 1 provided along the large-diameter portion 21 of the inner cylinder 2 is used. Basically, it receives the thrust load (T). That is, while the load (T) in the thrust direction is a small value, the force and the vibration are caused by the shear deformation of the vibration isolating rubber 5 provided between the outer cylinder 3 and the plastic insert 1. And so on. On the other hand, the thrust load (T)
Is large, the large-diameter portion 21 of the inner cylinder 2
When the plastic insert 1 formed along the direction of the arrow bears the thrust load (T), the relative displacement between the outer cylinder 3 and the inner cylinder 2 is suppressed. This also prevents the inner cylinder 2 from slipping out of the sliding bush. Than these things,
The mounting rigidity in the thrust direction will be increased,
Driving stability will also be improved. Also, the fiber layer 4 having good slipperiness so as to wrap the large diameter portion 21 against the twisting movement of the inner cylinder 2.
Is provided, unlike a countermeasure that is simply taken by the deformation of the anti-vibration rubber 5, a better follow-up property is exhibited. As a result, the followability of the suspension arm is improved, the hysteresis and the like are reduced, and the riding comfort is improved. Further, in this embodiment, a part of the vibration isolating rubber 5 is extended to form a seal rubber portion 51, and the seal rubber portion 51 covers the small diameter portions 22 provided at both ends of the inner cylinder 2. And the fiber layer 4 that is in sliding contact with the outer peripheral surface of the inner diameter 2. Therefore, the seal between the fiber layer 4 and the outer peripheral surface of the inner cylinder 2 is reliably performed. As a result, it is not necessary to separately provide a seal member as in the conventional case, and the outer peripheral surface of the inner cylinder 2 is reliably sealed by the tightening force of the seal rubber portion 51. Is prevented, and the wear and the like of the sliding surface can be prevented. Next, a second embodiment of the present invention will be described with reference to FIG.
This will be described based on FIG. This embodiment is also basically the same as the first embodiment. The difference is in the bulging portion 21 ′ provided at the center of the inner cylinder 2. That is, in the embodiment, as shown in FIG.
A bulging portion 21 ′ having a spherical shape is provided at the center of the inner cylinder 2, and the fiber layer 4 and the plastic insert 1 are provided along the bulging portion 21 ′. By adopting such a configuration, compared to the first embodiment, the twisting motion of the inner cylinder 2 is reduced.
It operates in a state of low resistance, and the better followability of the suspension arm is exhibited. That is, the one of the present embodiment exhibits a function similar to a ball joint.For example, when used in a link mechanism of a rear suspension, the rear suspension geometry is shifted to the understeer side or the toe-in side during braking or the like. It can be used for a configuration that the user wants to change positively. Except for the function for the prying exercise, the one of the previous first embodiment,
All have the same function. According to the present invention, there is provided an outer cylinder and an inner cylinder capable of relative rotational movement, and is provided between the outer cylinder and the inner cylinder and integrally joined to the outer cylinder. In addition, in the sliding bush having an anti-vibration rubber provided so as to be capable of sliding motion with the inner cylinder side, a central portion of the inner cylinder has a large-diameter portion having an outer diameter larger than an end portion thereof. A bulging portion is provided, on the other hand, a fiber layer having a small coefficient of sliding friction is provided integrally with the vibration-proof rubber on the inner peripheral surface side of the vibration-proof rubber, and outside the fiber layer, A plastic insert is provided along the large-diameter portion or the bulging portion and joined to the vibration-proof rubber and the fiber layer, and further covered with small-diameter portions formed near both ends of the inner cylinder. A configuration in which a part of the vibration-proof rubber is extended to provide a seal rubber part The vibration-absorbing rubber absorbs vibrations against minute vibrations in the direction perpendicular to the axis. The hysteresis is reduced by improving the followability of the arm, so that not only the ride comfort when the vehicle gets over a small bump but also the ride comfort relating to pitching and bouncing of the vehicle can be improved. At the same time, the adoption of the plastic insert increases the rigidity in the direction perpendicular to the axis and the rigidity in the axial direction (thrust direction), so that steering stability can be obtained. In addition, by providing a large-diameter portion or bulge at the center of the inner cylinder, the ability to follow the twisting movement between the inner cylinder and the outer cylinder is improved, improving ride comfort and stabilizing straight running during braking. It is possible to improve the performance. In addition, by adopting the plastic insert, even if the fiber layer is worn, the plastic insert can bear the load, so that there is no backlash or the like with the outer peripheral surface of the inner cylinder, and the steering stability is secured. It can be done. Further, the sliding bush exhibiting these various functions can be configured with a small number of components, and the manufacturing cost can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a half sectional view showing the entire configuration of a sliding bush according to a first embodiment of the present invention. FIG. 2 is a half sectional view showing an entire configuration of a sliding bush according to a second embodiment of the present invention. FIG. 3 is a half sectional view showing the overall configuration of a dry type sliding bush related to the present invention. FIG. 4 is a half sectional view showing the entire configuration of a conventional example. [Description of Signs] 1 Plastic insert 2 Inner cylinder 21 Large diameter section 21 ′ Swelling section 22 Small diameter section 3 Outer cylinder 4 Fiber layer 5 Anti-vibration rubber 51 Seal rubber section

Claims (1)

(57) [Claims 1] An outer cylinder and an inner cylinder capable of relative rotational movement are provided, between the outer cylinder and the inner cylinder, and integrally joined to the outer cylinder side. In addition, in a sliding bush having an anti-vibration rubber provided so as to be capable of sliding movement with the inner cylinder side, a large-diameter portion or an expanded portion having an outer diameter larger than an end of the sliding bush is provided at the center of the inner cylinder. On the other hand, a protruding part is provided, and on the inner peripheral surface side of the vibration-isolating rubber, Teflon
(Registered trademark) so that the fiber comes and the rubber
Woven so that polyester fiber with good bonding with comes
The fibrous layer of the double weave structure provided above vibration damping rubber integrally with,
Further, on the outside of such a fiber layer, a plastic insert is provided along the large-diameter portion or the bulging portion of the inner cylinder, and is bonded to the vibration-proof rubber and the fiber layer, A sliding bush comprising a configuration in which a part of the vibration-proof rubber is extended to provide a seal rubber portion so as to cover small-diameter portions formed near both ends of the inner cylinder.