JP3737630B2 - bush - Google Patents

Description

上記圧縮率（％）は、高くなると弾性部材３から外筒４が抜けにくくなるが、製作し易さ、弾性部材３の材質、耐久性等のバランスを勘案して、設定される。
【００２２】
以下に、ブッシュ１の製造方法の一例を説明する。
まず、鉄製の内筒２、ゴム製の弾性部材３および鋼製の外筒４を用いた。弾性部材３は、ＮＲ（天然ゴム）で、ゴム硬度がショアーＡＨs ６０°の材料を、電熱加硫プレスにて、温度１７０℃程度、時間約１５分、圧力約２００ｋｇ／ｃｍ² の条件で成形され、製作される。
【００２３】
そして、圧入治具を用いて外筒４に上記のとおり製作した弾性部材３を圧入し、そのあと、弾性部材３に内筒２を圧入してブッシュ１を製造する。
また、他の方法として、内筒２、弾性部材３および外筒４は上記のものと同じ形状とし、まず、内筒２を加硫金型にセットし、上記弾性部材３の製作条件と同様にして内筒２上に弾性部材３を成形かつ加硫接着して、更にこの状態の弾性部材３を外筒４に圧入してブッシュ１を製造する。
【００２４】
以上、本発明の好ましい実施形態を説明したが、具体的な構成はこれに限定されず、本発明の要旨を逸脱しない限り、変更・追加、各請求項における他の組み合わせが任意になし得ることは理解されるであろう。
【００２５】
【発明の効果】
以上詳述したように、本発明によれば、弾性部材の両端に設けた鍔部が１０ないし３０°の範囲で内側に傾斜していることにより、外筒側に接触する力が強く働き、外筒と弾性部材のシール性を増すことが出来る。したがって、車両に使用しても水や泥等異物がほとんど侵入せず、使用できる範囲が広がり、従来使用していたワッシャーやゴムカバーも必要なくなる効果がある。
さらに、外筒の端部と弾性部材の溝の底部に形成された空間が存在することにより、軸直角方向に荷重がかかった時に、外筒の鉤状の端部が直ちに溝の底部に当たるのではなく、弾性部材の弾発力を利用して端部が溝内を移動できるようにし、端部による弾性部材の磨耗および破損を防止出来る。
また、弾性部材に外筒を嵌めた際、鍔部の余分な上面がはみ出ないために、上記効果に加え、鍔部の外径を外筒の外径まで形成することが可能となって、より一層シール性を増すことが出来、しかも外観も良くなるという特徴がある。
【００２６】
さらに、鍔部のゴムと内筒の接合端部のゴムに凹部を形成することによって、外筒圧入後の応力集中による界面破損が防止され、かつ、弾性部材と外筒とがそれらの凹部と凸部とにより軸方向の抜け力に対して、二段構えで抵抗することにより、外筒の抜けづらさが一層向上する。したがって、上記効果に加え、軸方向に外筒が抜けたり、端部に径方向の強い力が働いても、ずれて隙間が生じたり、剥離せず耐久性が大幅に増加している。
【図面の簡単な説明】
【図１】本発明の実施の形態を示すブッシュの断面図である。
【図２】本発明の実施の形態を示す内筒に弾性部材を嵌めた状態の断面図である。
【図３】本発明の実施の形態を示す外筒の断面図である。
【図４】本発明の実施の形態を示す内筒と鍔部の接合部の構造を示す断面図である。
【図５】本発明の実施の形態を示し弾性部材を外筒を嵌める状態の断面図である。
【図６】従来例を示す図１と同状の断面図である。
【図７】従来例を示す図２と同状の断面図である。
【図８】従来例を示す図３と同状の断面図である。
【符号の説明】
１，ａ ブッシュ
２，ｂ 内筒
３，ｃ 弾性部材
４，ｄ 外筒
５，ｅ 鍔部
６ 軸線
７ 径方向面
８ 凹部
１０，ｆ 溝
１１ 端部
１２ 底部
１３ 空間
２０ 凹部
２１ 凸部
２２ 底
２３ 頂部
２４ 山部
２５ 裾部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bush used for a connecting portion between a vehicle body and a suspension arm of a vehicle, and more specifically, concentrically from the inside to the outside in the order of an inner cylinder, an elastic member, and an outer cylinder. It is related with the bush formed.
[0002]
[Prior art]
Bushes in which an elastic member is interposed between the inner cylinder and the outer cylinder are used at various coupling sites. For example, a conventional bush a used between a car body and a suspension arm of an automobile is concentric from the inside to the outside in the order of the inner cylinder b, the elastic member c, and the outer cylinder d as shown in FIGS. It is arranged. The elastic member c before being fitted into the outer cylinder d has a flange part e and a groove f connected to the flange part e at both ends thereof, and an outer peripheral surface between both grooves f forms a normal peripheral surface. Further, the outer cylinder d is forcibly fitted between both flanges e at both ends of the elastic member c.
[0003]
The bush a configured as described above is used between the vehicle body and the suspension arm, and the elastic member c interposed between the inner cylinder b and the outer cylinder d improves ride comfort. It is important to obtain the stability of maneuverability.
[0004]
[Problems to be solved by the invention]
However, the bush a is only weakly attached to the force acting in the axial direction because the round pipe-shaped outer cylinder d is only fitted between the flanges e and the grooves f at both ends of the elastic member c. There is a problem that the tube d is easily removed. Moreover, although it is strong against the force acting on the average in the radial direction due to the above structure, when the radial force is concentrated on one end of the outer cylinder d of the bush a, the outer cylinder d and the elastic member c Or a gap between the elastic member c and the inner cylinder b may be partly or wholly peeled off.
[0005]
And in the bush a used between the vehicle body and the suspension arm of the automobile, the seal width between the eaves part e and the outer cylinder d is narrow, and water and mud enter the gaps and peeled parts caused by the above causes. Not only the comfort and stable maneuverability are impaired, but also the occurrence of rust, stick-slip, and press-fitting slip due to fluctuations in compression rate, or the occurrence of abnormal noise, etc., resulting in a significant loss of durability. Result.
[0006]
The bush a is strong against the force acting on the average in the radial direction. However, when a strong force is applied repeatedly in the radial direction, the end of the outer cylinder d becomes the groove f portion of the elastic member c. The groove f is worn and eventually damaged.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide a highly durable bush that is free from breakthrough, breakage, or gaps with respect to forces acting in the axial and radial directions and does not allow foreign matter to enter.
[0008]
[Means for Solving the Problems]
The present invention has been proposed in order to achieve the above object, and is characterized by having the following configuration.
That is, according to the present invention, it is a bush formed concentrically from the inside to the outside in the order of the inner cylinder, the elastic member, and the outer cylinder,
The elastic member is provided with a concave portion on the outer peripheral surface, and a flange portion is formed on both outer sides of the concave portion through groove portions into which both ends of the outer cylinder are fitted,
The outer cylinder is formed in a bowl shape toward the inside so that a convex portion along the concave portion of the outer peripheral surface of the elastic member is formed and both ends are fitted into the groove portion of the elastic member,
When the both ends of the outer cylinder are fitted into the groove part connected to both flange parts of the elastic member, a space part exists between the bottom part of the groove and the end part of the outer cylinder,
The elastic member before being disposed on the outer cylinder is inclined inwardly within a range of 10 to 30 ° with respect to a radial plane perpendicular to the axis of the elastic member, with the flanges provided at both ends thereof. A bush is provided that is held while being pressed in the axial direction by a flange .
[0009]
Further, according to the present invention, there is provided the bushing in which the upper surface of the flange portion is inclined inwardly in the range of 5 to 15 ° with respect to the axis.
[0010]
Moreover, according to this invention, the said bush with which the joining end part of the rubber | gum of the said collar part and an inner cylinder is integrated via the recessed part formed in the joining end part side of rubber | gum is provided.
[0013]
Moreover, according to this invention, the said bush which vulcanized-bonded the said inner cylinder and the said elastic member is provided.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
A feature of the bush of the present invention is a bush formed concentrically from the inner side to the outer side in the order of the inner cylinder, the elastic member, and the outer cylinder, and the elastic member has a recess on the outer peripheral surface, Both outer sides of the recess are formed with flanges through grooves into which both ends of the outer cylinder are fitted, and the outer cylinder is formed with a convex portion along the recess on the outer peripheral surface of the elastic member, Is formed in a bowl shape toward the inside so as to be fitted into the groove portion of the elastic member, and when both ends of the outer cylinder are fitted into the groove portions connected to both flange portions of the elastic member, the bottom portion of the groove There is a space between the end of the outer cylinder, and the elastic member before being arranged on the outer cylinder has a radial surface perpendicular to the axis of the elastic member. inclined inwardly in the range from of 30 ° 10 no against, it holds while pressing axially outer cylinder by a flange portion There is a point.
In this bush, preferably, the upper surface of the flange portion of the elastic member is inclined inwardly in the range of 5 to 15 ° with respect to the axis.
Furthermore, since the joint end part of the rubber of the collar part and the inner cylinder is integrated through the concave part, when the stress is concentrated on the joint part, the concave part absorbs the stress and the bonding interface is It can be prevented from being damaged.
Due to the characteristics of the shape, the force of contact with the outer cylinder side of the elastic member acts strongly, increasing the sealing performance, and as described above, it is possible to eliminate the disadvantages of the conventional bushing that the outer cylinder is easily detached from the elastic member. .
[0015]
Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a cross-sectional view of a bush showing an embodiment of the present invention, FIG. 2 is a cross-sectional view showing an embodiment of the present invention with an elastic member fitted to an inner cylinder, and FIG. 3 is an embodiment of the present invention. shows cross-sections of the outer tube, and FIG. 4 is a sectional view showing a state where the adhesive ends of the rubber and the inner tube of the flange are integrated via the recess. In the figure, the bush 1 is roughly arranged concentrically from the inside to the outside in the order of the inner cylinder 2, the elastic member 3 and the outer cylinder 4, and the elastic member before being arranged on the outer cylinder 4. 3, to the flange portion 5 provided at both ends is no angle 10 with respect to the radial plane 7 perpendicular to the axis 6 of the elastic member 3 30 °, preferably inclined inwardly in the range of 18 to 23 °, the outer cylinder Is held while being pressed in the axial direction by the flange .
[0016]
The inner cylinder 2 is a relatively thick cylindrical body, usually made of aluminum die cast, and press-fitted into the elastic member 3. As described above, the elastic member 3 is provided with the flanges 5 at both ends thereof through the grooves 10 into which the flanged end portions 11 of the outer cylinder are fitted . As shown in FIG. 2, the flange 5 is inclined inwardly within an angle (α) in the range of 10 to 30 °, and the angle (α) is set to 30 ° at the maximum. In addition, from the viewpoint of the adhesion between the flange portion 5 and the outer cylinder 4, it is better to have an angle (α). However, if it exceeds 30 °, it is not preferable because the elastic member 3 is forcedly pressed.
On the other hand, when the angle (α) is 10 ° or less, the adhesion between the flange portion 5 of the elastic member 3 and the outer cylinder 4 becomes weak, and the expected sealing performance cannot be obtained. As can be seen from FIGS. 1, 3, and 5, both end portions 11 of the outer cylinder are formed in a bowl shape toward the inside so as to fit into the groove 10 of the elastic member 3 . The flange portion 5 is slightly thicker from the distal end portion 5a to the proximal end portion 5b, and is more closely attached to the outer tube 4 when the outer tube 4 is fitted.
[0017]
The upper surface of the flange 5 is inclined inwardly within an angle (β) with respect to the axis 6 of 5 to 15 °, preferably 8 to 12 °. This is because, when the upper surface of the flange portion 5 of the elastic member 3 before being disposed on the outer cylinder 4 is parallel to the axis 6, the flange is inclined when the elastic member 3 is fitted to the outer cylinder 4. The part 5 rises, and the upper surface of the flange part 5 is not preferable in terms of the function and appearance of the outer cylinder 4. As a result, when the elastic member 3 is disposed on the outer cylinder 4, the upper surface of the flange portion 5 is parallel to the axis 6, so that the diameter of the flange portion 5 is maximized and the above-mentioned adhesion is achieved. It is a little higher and looks better. Note that this angle (β) needs to be changed slightly corresponding to the angle (α).
[0018]
The groove 10 connected to the flange portion 5 of the elastic member 3 is formed considerably deep. The depth of the groove 10 is such that the end 11 of the outer cylinder 4 is in wide contact with the side surface of the groove 10 when the flange-shaped end portions 11 of the outer cylinder 4 are fitted into the groove 10. A predetermined space 13 is set between the bottom portion 12 of the tube and the end portion 11 of the outer cylinder 4. This space 13 is not expected because the flange- shaped end portion 11 of the outer cylinder 4 immediately hits the bottom portion 12 of the groove 10 when a load is applied in the direction perpendicular to the axis. 11 can be moved. Therefore,
As long as the elastic force of the elastic member 3 can be expected, wear and breakage of the elastic member 3 due to the end 11 can be prevented.
[0019]
Stress may concentrate on the joint end portion between the rubber of the flange portion and the inner cylinder provided at both end portions after the outer cylinder is press-fitted, and the adhesive interface may be damaged. In the present invention, if necessary, a recess 8 formed on the side of the rubber joint end as shown in FIG. 4 is formed at the joint end of the rubber of the collar portion and the inner cylinder, and the rubber is integrally formed through this recess. As a result, the adhesive interface is prevented from being damaged even when stress is concentrated on the joint end. According to the experiments by the present inventors, R of the recessed portion and the bottom portion constituting the recessed portion are both 0.5 to 3, preferably about 0.5 to 1, and the depth is preferably about 1 to 2 mm. When the value of R becomes larger than that, the sealing performance of the heel portion decreases.
[0020]
A concave portion 20 is provided on the outer peripheral surface between both flange portions 5 of the elastic member 3, and a convex portion 21 along the concave portion 20 is provided on the outer cylinder 4. Therefore, the groove 10 of the elastic member is formed on both outer sides of the recess 20 . The outer diameter (φA) at the bottom 22 of the concave portion 20 of the elastic member 3 is set larger than the inner diameter (φB) at the top portion 23 of the convex portion 21 of the outer cylinder 4 (φA> φB). Further, the outer diameter (φC) at the crest portion 24 of the concave portion 20 of the elastic member 3 is set to be larger (φC> φD) than the inner diameter (φD) at the skirt portion 25 of the convex portion 21 of the outer cylinder 4. Therefore, the elastic member 3 and the outer cylinder 4 have a two-stage structure due to the concave portion 20 and the convex portion 21, so that the resistance force against the axial pulling force is increased and it is difficult to pull out.
[0021]
Here, the compression rate between the elastic member 3 and the outer cylinder 4, that is, the tightening margin of the elastic member 3 by the outer cylinder 4 is preferably 20 to 40%, particularly about 30%.
The compression rate can be expressed by the following formula.

When the compression rate (%) is increased, the outer cylinder 4 is less likely to be removed from the elastic member 3, but is set in consideration of the balance between ease of manufacture, the material of the elastic member 3, durability, and the like.
[0022]
Below, an example of the manufacturing method of the bush 1 is demonstrated.
First, an iron inner cylinder 2, a rubber elastic member 3, and a steel outer cylinder 4 were used. The elastic member 3 is NR (natural rubber), and a material with a rubber hardness of Shore AHs 60 ° is molded by an electrothermal vulcanization press at a temperature of about 170 ° C., a time of about 15 minutes, and a pressure of about 200 kg / cm ^2. And produced.
[0023]
Then, the elastic member 3 manufactured as described above is press-fitted into the outer cylinder 4 using a press-fitting jig, and then the inner cylinder 2 is press-fitted into the elastic member 3 to manufacture the bush 1.
As another method, the inner cylinder 2, the elastic member 3, and the outer cylinder 4 have the same shape as described above. First, the inner cylinder 2 is set in a vulcanization mold, and the manufacturing conditions of the elastic member 3 are the same. Then, the elastic member 3 is molded and vulcanized and bonded onto the inner cylinder 2, and the elastic member 3 in this state is pressed into the outer cylinder 4 to manufacture the bush 1.
[0024]
The preferred embodiment of the present invention has been described above, but the specific configuration is not limited to this, and modifications, additions, and other combinations in each claim can be arbitrarily made without departing from the gist of the present invention. Will be understood.
[0025]
【The invention's effect】
As described in detail above, according to the present invention, the flanges provided at both ends of the elastic member are inclined inwardly in the range of 10 to 30 °, so that the force to contact the outer cylinder side works strongly, The sealing performance between the outer cylinder and the elastic member can be increased. Therefore, even if it is used for a vehicle, foreign matter such as water and mud hardly penetrates, and the usable range is widened, and there is an effect that a conventionally used washer and rubber cover are not necessary.
In addition, since there is a space formed at the end of the outer cylinder and the bottom of the groove of the elastic member, when a load is applied in a direction perpendicular to the axis, the bowl-shaped end of the outer cylinder immediately hits the bottom of the groove. Instead, it is possible to use the elastic force of the elastic member to move the end portion in the groove, and to prevent the elastic member from being worn and damaged by the end portion .
In addition, when the outer cylinder is fitted to the elastic member, the upper surface of the collar portion does not protrude, so in addition to the above effects, the outer diameter of the collar portion can be formed up to the outer diameter of the outer cylinder, The sealing property can be further increased, and the appearance is also improved.
[0026]
Further, by forming a recess in the rubber of the junction end of the rubber and the inner tube of the flange portion, the interface breakage is prevented due to stress concentration after the outer cylinder press-fitted, and the elastic member and the outer cylinder thereof recesses By resisting in a two-stage manner against the axial pulling force by the projection and the convex portion, the difficulty of pulling out the outer cylinder is further improved. Therefore, in addition to the above effects, even if the outer cylinder is pulled out in the axial direction or a strong radial force is applied to the end portion, it is displaced and a gap is formed, and durability is greatly increased without peeling.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a bush showing an embodiment of the present invention.
FIG. 2 is a cross-sectional view of a state in which an elastic member is fitted to an inner cylinder showing an embodiment of the present invention.
FIG. 3 is a cross-sectional view of an outer cylinder showing an embodiment of the present invention.
FIG. 4 is a cross-sectional view showing a structure of a joint portion between an inner cylinder and a collar portion showing an embodiment of the present invention.
FIG. 5 is a cross-sectional view showing an embodiment of the present invention in a state in which an outer cylinder is fitted to an elastic member.
6 is a cross-sectional view similar to FIG. 1 showing a conventional example.
FIG. 7 is a cross-sectional view similar to FIG. 2 showing a conventional example.
8 is a cross-sectional view similar to FIG. 3 showing a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1, a Bush 2, b Inner cylinder 3, c Elastic member 4, d Outer cylinder 5, e collar part 6 Axis 7 Radial surface 8 Concave 10, f Groove 11 End 12 Bottom 13 Space 20 Concave 21 Convex 22 Bottom 23 top 24 mountain 25 hem

Claims (4)

A bush formed concentrically from the inside to the outside in the order of the inner cylinder, the elastic member, and the outer cylinder,
The elastic member is provided with a concave portion on the outer peripheral surface, and a flange portion is formed on both outer sides of the concave portion through groove portions into which both ends of the outer cylinder are fitted,
The outer cylinder is formed in a bowl shape toward the inside so that a convex portion along the concave portion of the outer peripheral surface of the elastic member is formed and both ends are fitted into the groove portion of the elastic member,
When the both ends of the outer cylinder are fitted into the groove part connected to both flange parts of the elastic member, a space part exists between the bottom part of the groove and the end part of the outer cylinder,
The elastic member before being disposed on the outer cylinder is inclined inwardly within a range of 10 to 30 ° with respect to a radial plane perpendicular to the axis of the elastic member, with the flanges provided at both ends thereof. A bush characterized by being held while being pressed in the axial direction by a flange .   The bush according to claim 1, wherein an upper surface of the flange portion is inclined inwardly within a range of 5 to 15 ° with respect to the axis. The bush according to claim 1 or 2, wherein a joint end portion between the rubber of the flange portion and the inner cylinder is integrated through a recess formed on the joint end portion side of the rubber . The bush according to any one of claims 1 to 3 , wherein the inner cylinder and the elastic member are vulcanized and bonded.

Images