JP3717740B2 - Stabilizer bush - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a stabilizer bush for holding a stabilizer bar of a vehicle.
[0002]
[Prior art]
FIG. 6 shows a general structure of a stabilizer bush, and a thick-walled cylindrical rubber elastic body 10 has a stabilizer bar S of a vehicle inserted and held in the cylinder. The rubber elastic body 10 has a flat top surface in contact with a mounting surface (not shown) of the vehicle body, and a U-shaped outer peripheral surface is held by a substantially U-shaped bracket 20. A bolt is screwed into the bolt hole 201 to be fixed to the mounting surface of the vehicle body. At both ends of the rubber elastic body 10, flanges 101 that project in the radial direction are provided to prevent the rubber elastic body 10 from coming off the bracket 20.
[0003]
In recent years, as shown in FIG. 7, a stabilizer bush in which the rubber elastic body 10 has a two-layer structure of an inner layer rubber 10A and an outer layer rubber 10B and the inner layer rubber 10A is made of a highly slidable rubber material has been studied. . In the stabilizer bush configuration of FIG. 6, it is difficult to achieve both steering stability and riding comfort. If the rigidity of the rubber elastic body 10 is increased in order to improve steering stability, the riding comfort is lowered, and conversely, the rubber elastic body 10 is softened. Then, there was a problem that the driving stability was lowered. However, in the configuration of FIG. 7, the sliding resistance of the inner layer rubber 10A is small, so that the ride comfort is improved, and the outer layer rubber 10B is harder than the inner layer rubber 10A and the rigidity is improved. It becomes possible. Moreover, generation | occurrence | production of the noise by the sudden relative displacement of 10 A of inner layer rubbers and the stabilizer bar S can also be prevented.
[0004]
[Problems to be solved by the invention]
However, in recent vehicle designs, there are many cases where there is not enough room between the components in order to house the mounted components in the smallest possible space. For this reason, if a lateral shift occurs in which the stabilizer bar S moves relative to the rubber elastic body 10 in the axial direction, there is a problem that the stabilizer bar S interferes with surrounding components. As a countermeasure, as shown in FIG. 7, a lateral displacement stopper 2 made of a metal ring is provided around the stabilizer bar S to regulate the relative movement amount. The lateral displacement stopper 2, the rubber elastic body 10, There is a new problem that noises occur due to interference.
[0005]
That is, an object of the present invention is to provide a stabilizer bush structure that can prevent the generation of noise due to interference with the lateral slip stopper without impairing the steering stability and riding comfort in the configuration in which the lateral shift stopper is provided on the stabilizer bar. It is to provide.
[0006]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a stabilizer bush for inserting and holding a stabilizer bar in a rubber elastic body formed into a cylindrical shape and holding an outer peripheral surface of the rubber elastic body by a bracket attached to a vehicle body. Is provided with a stopper member for restricting the axial movement of the rubber elastic body. The rubber elastic body, and an inner layer rubber made of a high sliding resistance rubber is a two-layer structure of an outer layer rubber having a flange portion projecting radially at both ends and laminated on the outer periphery thereof, the hardness of the outer layer rubber The hardness of the inner layer rubber or higher. Further, at least the stopper member side end surface of the rubber elastic body is provided with a sliding surface that is integral with the inner layer rubber, protrudes toward the stopper member side from the end surface of the outer layer rubber, and does not reach the flange portion. ing.
[0007]
According to the above configuration, since the rubber elastic body has the protruding sliding surface made of a highly slidable rubber having a low frictional resistance on the end surface facing the stopper member, the stabilizer bar is laterally displaced. Also, only the protruding sliding surface comes into contact with the stopper member and no abnormal noise is generated. Further, the rubber elastic body, because the inner layer side is high sliding rubber than-than outer layer to hold the stabilizer bar is inside and outside two-layer structure consisting of a high hardness rubber than the inner layer side, steering stability, ride comfort both Are better. Therefore, it is possible to realize a more comfortable environment by achieving both handling stability and riding comfort, and preventing abnormal noise due to interference with the lateral stopper.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
First, a reference example of a stabilizer bush structure that is considered to be able to prevent the generation of abnormal noise due to interference with the stopper member of the stabilizer bar without impairing the steering stability and riding comfort will be described with reference to FIGS. FIG. 1A shows a state in which the stabilizer bush of the first reference example is assembled to the stabilizer bar S. In the drawing, the thick cylindrical rubber elastic body 1 constituting the stabilizer bush is highly slidable. It consists of an inner layer rubber 1A made of a conductive rubber and an outer layer rubber 1B on the outer periphery thereof. The rubber elastic body 1 has a flange portion 11 projecting radially in the outer periphery of both end portions, and a substantially U-shaped bracket 3 in which the outer peripheral surface of the rubber elastic body 1 between the flange portions 11 is bolted to a vehicle frame. It is supposed to be held at.
[0015]
FIGS. 1B to 1D are diagrams showing a detailed configuration of the rubber elastic body 1 of the first reference example . As shown in FIG. 1C, the rubber elastic body 1 is inserted and held by the stabilizer bar S. It has a two-layer structure of a cylindrical inner layer rubber 1 </ b> A and an outer layer rubber 1 </ b> B laminated on the outer periphery thereof. As shown in FIG. 1D, the inner layer rubber 1A has a polygonal outer shape, for example, a regular octagon, thereby preventing displacement and rotation at the bonding interface between the inner layer rubber 1A and the outer layer rubber 1B. Increases bondability.
[0016]
The outer layer rubber 1B has a U-shaped outer peripheral shape, and the top surface is a flat surface. Both end portions of the outer layer rubber 1 </ b> B have the outer peripheral edge projecting in the radial direction with a constant width to form the flange portion 11. As shown in FIG. 1C, the mounting surface with which the rubber elastic body 1 comes into contact with the mounting to the vehicle frame F has a shape in which a part protrudes downward in accordance with the top surface shape of the outer layer rubber 1B. Yes. In this way, the movement of the rubber elastic body 1 in the axial direction can be restricted and deviation from the bracket 3 can be prevented.
[0017]
In FIG. 1, a lateral displacement stopper 2 as a stopper member is fixed around the stabilizer bar S on one end face (right end face in FIG. 1) side of the rubber elastic body 1. The lateral displacement stopper 2 is annular and is made of metal or rubber. When the stabilizer bar S is laterally displaced with respect to the rubber elastic body 1, the lateral displacement stopper 2 abuts against the rubber elastic body 1 and restricts its movement. Prevent interference with parts.
[0018]
In this reference example, a sliding surface 12 made of a highly slidable rubber is provided integrally with the inner rubber layer 1A on the end surface of the rubber elastic body 1 facing the lateral displacement stopper 2. The sliding surface 12 is desirably larger than the area of the lateral displacement stopper 2, and here, as shown in FIG. 2 (b), the entire surface of the right end surface of the rubber elastic body 1 (front of FIG. 1 (b)) is slid. The moving surface 12 is assumed. Although the thickness of the sliding surface 12 is about half of the flange portion 11 (usually about 3 mm), the outer peripheral edge of the sliding surface 12 has a thickness of about 1 mm, and the back side of the outer rubber 1B. It supports by the thin rib 13 which protrudes from the outer peripheral part of this end surface. Thus, by installing the protruding thin ribs 13 on the outer peripheral edge of the end surface of the outer rubber 1B, there is an effect of preventing the high-sliding rubber from protruding during molding. That is, since the high slidability rubber does not contact the bracket 3, the holding property of the bracket 3 is not lowered.
[0019]
Further, as shown in FIGS. 1B and 1C, the rubber elastic body 1 is provided with a rectangular identification rib 14 at the lower end of the flange portion 11 on the sliding surface 12 side. The surface of the identification rib 14 is covered with a highly slidable rubber and integrated with the sliding surface 12. The identification rib 14 can easily identify the directionality of the rubber elastic body 1, that is, the end surface on the sliding surface 12 side, and can be easily attached to the stabilizer bar S. Further, when an identification tape 15 for identifying the diameter of the insertion hole of the stabilizer bar S is provided on the surface of the identification rib 14, when molding the rubber elastic body 1 having different hole diameters, only the upper mold for molding the inner layer rubber 1A is used. Since the identification becomes possible by changing, the mold production cost can be reduced. Further, since the identification take-in 15 is at a position where it does not interfere with the lateral displacement stopper 2, the characteristics are not affected.
[0020]
The highly slidable rubber constituting the inner layer rubber 1A and the sliding surface 12 is provided with high slidability by blending a higher fatty acid amide with the rubber as the base material. The base rubber is not particularly limited. For example, natural rubber (NR), butadiene rubber (BR), blend rubber of natural rubber and butadiene rubber (NR / BR), isoprene rubber (IR), styrene butadiene rubber ( SBR), chloroprene rubber (CR), nitrile rubber (NBR), ethylene propylene diene copolymer rubber (EPDM), butyl rubber (IIR), chlorinated butyl rubber (Cl-IIR), and blended rubbers thereof can be used. Preferably, a blend rubber (NR / BR) of natural rubber and butadiene rubber is suitably used.
[0021]
The higher fatty acid amide blended in the base rubber of the high slidable rubber functions as a lubricant by blooming from the base rubber during use and improves the slidability. Specific examples of higher fatty acid amides include saturated and unsaturated fatty acid amides having 12 to 22 carbon atoms such as oleic acid amide, palmitic acid amide, stearic acid amide, erucic acid amide, and preferably oleic acid amide Is used. The blending amount of the higher fatty acid amide in the inner layer rubber 1A is desirably set to a necessary amount when the rubber elastic body 1 is composed of only a high sliding rubber. However, if the amount of the higher fatty acid amide kneaded into the inner layer rubber 1A becomes too large, there is a risk of adversely affecting the rubber physical properties. Usually, the blending amount of the higher fatty acid amide in the base rubber is 5 to 30% by weight. % Range. When the amount of the higher fatty acid amide is large, an excessive higher fatty acid amide can be kneaded in advance in the outer layer rubber 1B.
[0022]
The highly slidable rubber is formed by blending the base rubber and the higher fatty acid amide at a predetermined blending ratio. At this time, generally known additives such as a vulcanizing agent, a vulcanization accelerator, a vulcanization aid, and a processing aid can be used. Examples of the vulcanizing agent include sulfur, peroxide, metal oxide, polyamine and the like, and are usually used in the range of 0.1 to 10% by weight. As the vulcanization accelerator, sulfenamide, thiazole, thiuram, dithiocarbamate, xanthate, etc. are usually used in the range of 0.1 to 10% by weight. As the vulcanization aid, zinc oxide or the like is usually used, and the blending amount is usually in the range of 3 to 15% by weight. As processing aids, fatty acids such as stearic acid and fatty oils are used.
[0023]
The outer layer rubber 1B is made of the same or similar rubber material as the base rubber of the inner layer rubber 1A. Specifically, for example, when a blend rubber (NR / BR) of natural rubber and butadiene rubber is used as the base rubber of the inner layer rubber 1A, natural rubber (NR), butadiene rubber (BR), or natural rubber And butadiene rubber blend rubber (NR / BR) or the like can be used, and the bonding property between the two is improved. In particular, it is preferable that the outer layer rubber 1B is made of a natural rubber material because fatigue resistance is high and durability is improved.
[0024]
Moreover, it is preferable that the rubber hardness of the outer layer rubber 1B is equal to or higher than the rubber hardness of the inner layer rubber 1A because the rigidity of the entire rubber elastic body 1 is improved. Usually, high slidable rubber has a rubber hardness of about Hs65 in order to improve wear resistance. Therefore, the outer layer rubber 1B may be blended so that the rubber hardness of the outer layer rubber 1B is about Hs65 or more. Highly slidable rubber gives slidability by blooming higher fatty acid amide from the inside when stabilizer bush is used, but depending on the combination of inner layer rubber 1A and outer layer rubber 1B, blooming higher fatty acid amide may be the outer layer. In some cases, the rubber 1B side may be shifted to. Even in such a case, the lateral displacement of the stabilizer bush from the bracket can be suppressed by increasing the rigidity of the entire rubber elastic body 1 and the flange 11.
[0025]
When manufacturing the stabilizer bush having the above-described structure, usually, the outer layer rubber 1B is first molded and vulcanized or semi-vulcanized, and then the inner layer rubber 1A and the highly slidable rubber that becomes the sliding surface 12 are formed in the mold. The method of injecting into vulcanization and vulcanization molding is adopted. Further, the present invention is not limited to this method, and other methods such as a method in which each rubber is preliminarily molded into a predetermined shape and bonded are also possible.
[0026]
According to the above configuration, since the sliding surface 12 made of highly slidable rubber is provided on the end surface of the rubber elastic body 1 facing the lateral displacement stopper 2 and the area thereof is larger than that of the lateral displacement stopper 2, the stabilizer bar S is Even if the rubber elastic body 1 and the lateral displacement stopper 2 come into contact with each other due to lateral displacement, the frictional resistance between them is very small and no abnormal noise is generated. Since the sliding surface 12 can be molded integrally with the inner layer rubber 1A made of a highly slidable rubber, it is easy to manufacture. In addition, since the inner layer rubber 1A is made of a highly slidable rubber, the sliding resistance with the stabilizer bar S is lowered, the riding comfort is improved, and the generation of noise due to relative rotation can be prevented. On the other hand, the outer layer rubber 1B is made of a natural rubber-based material having high hardness, so that the rigidity is increased, the steering stability is improved, and the durability is also excellent. Furthermore, since the inner layer rubber 1A is made of a rubber material similar to the outer layer rubber 1B and the outer peripheral shape of the inner layer rubber 1A is a polygon, the bonding property is also high.
[0027]
FIG. 2 shows a second reference example. In the first reference example, the entire end surface of the rubber elastic body 1 is the sliding surface 12, but when the lateral displacement stopper 2 is relatively small, the sliding surface 12 is partially formed. You can also. As in this reference example, the sliding surface 12 has the same shape as the end surface of the rubber elastic body 1 on which the sliding surface 12 is provided (the front surface in FIG. 2A, the left end surface in FIG. 2B) and is slightly smaller. . However, it is preferable that the sliding surface 12 has a larger area than the lateral displacement stopper 2 so that the lateral displacement stopper 2 does not contact the surface outside the sliding surface 12.
[0028]
In the first reference example , the inner layer rubber 1A has a polygonal outer peripheral shape. However, in the second reference example, as shown in FIG. 2 (c), the outer layer rubber 1A has an outer peripheral shape of the outer layer rubber 1B. It has the same shape. Thus, when the inner layer rubber 1A has a shape similar to the outer layer rubber 1B, it is easier to increase the volume than when it has a circular or polygonal cross section, and the total amount of lubricant contained in the rubber can be increased, ensuring slidability. From the viewpoint of Further, since it has a cornered shape, it has the same effect as the first reference example with respect to slippage prevention and rotation prevention.
[0029]
Even with the above configuration, the same effect of preventing interference with the lateral displacement stopper 2 is obtained, and the outer layer rubber 1B is provided around the outer periphery of the sliding surface 12, so that the moldability is good. Further, since the outer peripheral shape of the inner layer rubber 1A is a shape having corners, it has the same effect as the first reference example with respect to displacement prevention and rotation prevention. In addition, since the sliding surface 12 has the same shape as the end surface of the rubber elastic body 1, a portion that does not come into contact with the circular lateral displacement stopper 2 is formed on the left and right ends of the upper side, as shown in FIG. If the identification take 15 is disposed on the other side, it is possible to prevent interference with the lateral displacement stopper 2.
[0030]
Here, in each of the above reference examples , the sliding surface 12 is provided only on one end surface of the rubber elastic body 1, but the sliding surface 12 may be provided on both end surfaces. An example is shown below as a third reference example .
[0031]
As shown in FIGS. 3A and 3B, in the third reference example , the portion from the left and right end surfaces of the rubber elastic body 1 to the thickness of the flange portion 11 is composed of a highly slidable rubber integral with the inner layer rubber 1A. are doing. That is, the entire left and right end surfaces are the sliding surfaces 12. In this configuration, the outer layer rubber 1B is sandwiched between the flange portions 11 at both ends and securely held, so that the adhesion between the inner and outer layers is improved. There is no risk of occurrence.
[0032]
FIG. 4 shows an embodiment of the present invention . In the present invention, a part of one end surface (the right end surface in the figure) of the rubber elastic body 1 is used as a sliding surface 12 made of a highly slidable rubber (FIGS. 4C and 4D), and this sliding The surface 12 is slightly protruded from the outer layer rubber 1B (FIG. 4A). As shown in FIG. 4B, the lateral displacement stopper 2 facing the sliding surface 12 has a polygonal shape such as a regular hexagon and is formed slightly larger than the sliding surface 12. The sliding surface 12 is circular, and the outer peripheral shape of the inner layer rubber 1A is a polygon, for example, a regular octagon.
[0033]
When securing the rubber elastic body 1 from the bracket 3 is regarded as important, in order to ensure the rigidity of the flange portion 11 protruding from the end portion of the outer rubber 1B , sliding as shown in FIG. It is desirable to make the surface 12 small so that the highly slidable rubber does not cover the flange portion 11, and to form the flange portion 11 only with the outer layer rubber 1B having high hardness . By doing so, since the sliding surface 12 protrudes, the lateral displacement stopper 2 does not contact the outer layer rubber 1B, preventing interference between the lateral displacement stopper 2 and the outer layer rubber 1B and securing the rigidity of the flange portion 11. Both can be achieved.
[0034]
FIG. 5 shows a modification of the embodiment of the present invention . The outer peripheral shape of the sliding surface 12 is a substantially rectangular shape, and the area is relatively large as long as it does not cover the flange portion 11. When the sliding surface 12 is smaller than the lateral displacement stopper 2, the stress concentration at the time of contact tends to be a problem, but the stress concentration can be reduced by increasing the area. The shape and area of the sliding surface 12 can be appropriately changed according to the required rigidity of the flange portion 11 and the like. In addition, if the surface of the sliding surface 12 is subjected to texture processing, blast processing, or the like to form irregularities, the contact area with the lateral displacement stopper 2 is reduced, which is more effective for the generation of abnormal noise.
[Brief description of the drawings]
FIG. 1 shows a first reference example of a stabilizer bush , (a) is a view showing a state where the stabilizer bush is assembled to a stabilizer bar, (b) is a cross-sectional view taken along the line II, and (b) is a stabilizer. The axial front view of a bush, (c) is the II-II sectional view taken on the line of (b), (d) is the III-III sectional view taken on the line (c).
2 shows a second reference example of a stabilizer bush , (a) is a front view in the axial direction of the stabilizer bush, (b) is a sectional view in the axial direction of the stabilizer bush, and (c) is an IV- It is IV sectional view.
3A and 3B show a third reference example of the stabilizer bush, wherein FIG. 3A is a front view in the axial direction of the stabilizer bush, and FIG. 3B is a cross-sectional view in the axial direction of the stabilizer bush.
4A and 4B show an embodiment of the present invention, in which FIG. 4A is an axial sectional view of a stabilizer bush provided with a lateral displacement stopper, FIG. 4B is an axial front view of the stabilizer bush provided with a lateral displacement stopper, ) Is a front view of the stabilizer bush in the axial direction, and (d) is a cross-sectional view taken along line VV in (a).
5 is a cross-sectional view of the stabilizer bush in the direction perpendicular to the axis , showing a modification of the stabilizer bush of the present invention shown in FIG . 4. FIG.
FIG. 6 is a perspective view showing a state in which a conventional stabilizer bush is assembled to a stabilizer bar.
FIG. 7 is a cross-sectional view showing a state where a conventional stabilizer bush is assembled to a stabilizer bar.

Claims (1)

A stabilizer bar is inserted and held in a rubber elastic body formed into a cylindrical shape, and the outer peripheral surface of the rubber elastic body is held by a bracket attached to a vehicle body, and the rubber elastic body moves in the axial direction around the stabilizer bar. in the stabilizer bush in which a stopper member for regulating an inner layer rubber made of a high sliding resistance rubber the rubber elastic body, and an outer layer rubber having a pair of flanges projecting radially at both ends and laminated on the outer periphery thereof The outer layer rubber has a hardness equal to or higher than the hardness of the inner layer rubber, and is integral with the inner layer rubber at least on the end surface of the rubber elastic body on the stopper member side, and more than the end surface of the outer layer rubber. A stabilizer bushing characterized by having a sliding surface that protrudes toward the stopper member and has a height that does not extend over the flange portion .

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