JP2017025950A - Bump stopper and buffer - Google Patents

Bump stopper and buffer Download PDF

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Publication number
JP2017025950A
JP2017025950A JP2015142280A JP2015142280A JP2017025950A JP 2017025950 A JP2017025950 A JP 2017025950A JP 2015142280 A JP2015142280 A JP 2015142280A JP 2015142280 A JP2015142280 A JP 2015142280A JP 2017025950 A JP2017025950 A JP 2017025950A
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Prior art keywords
bump stopper
outer shell
grounding
curved surface
grounding portion
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均 鈴木
Hitoshi Suzuki
均 鈴木
圭祐 中西
Keisuke Nakanishi
圭祐 中西
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KYB Corp
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KYB Corp
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Priority to JP2015142280A priority Critical patent/JP2017025950A/en
Priority to PCT/JP2016/068658 priority patent/WO2017010254A1/en
Publication of JP2017025950A publication Critical patent/JP2017025950A/en
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32—Details
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F9/00—Springs, vibration-dampers, shock-absorbers, or similarly-constructed movement-dampers using a fluid or the equivalent as damping medium
    • F16F9/32—Details
    • F16F9/58—Stroke limiting stops, e.g. arranged on the piston rod outside the cylinder

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  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Fluid-Damping Devices (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a bottomed cylindrical bump stopper preventing concentration of stress applied to the boundary between the bottom part and cylindrical part of the bump stopper, and having high durability, and provide a buffer including the bump stopper.SOLUTION: Included are ground parts provided at the bottom part of a bottomed cylindrical bump stopper so as to be aligned in a circumferential direction, and a projection part provided at a cylindrical part. The projection part is arranged between the ground parts in an axial view.SELECTED DRAWING: Figure 2

Description

この発明は、バンプストッパ及び緩衝器に関する。   The present invention relates to a bump stopper and a shock absorber.

従来、緩衝器は、有底筒状のアウターシェルとこのアウターシェル内を出入り自在に移動するロッドとを備え、アウターシェルの端部にはバンプストッパを、ロッドの反アウターシェル側端にはバンプクッションラバーをそれぞれ設けている。   Conventionally, a shock absorber has a bottomed cylindrical outer shell and a rod that can move freely in and out of the outer shell. A bump stopper is provided at the end of the outer shell, and a bump is provided at the end opposite to the outer shell of the rod. Cushion rubber is provided.

これにより、ロッドがアウターシェル内に侵入する緩衝器の最大収縮時にバンプクッションラバーとバンプストッパとを突き当て、バンプクッションラバーの弾性変形により最大収縮時に発生する衝撃を緩和している。   As a result, the bump cushion rubber and the bump stopper are brought into contact with each other during the maximum contraction of the shock absorber in which the rod enters the outer shell, and the impact generated during the maximum contraction is alleviated by the elastic deformation of the bump cushion rubber.

バンプストッパは、ロッドの挿通を許容して、アウターシェルへ装着できるように、底部に孔を備えてキャップ状とされ、筒部に内方へ突出する複数の突起部と、底部にアウターシェルの上端に当接する接地部を備えてなる（例えば、特許文献１）。   The bump stopper has a cap shape with a hole at the bottom so as to allow the rod to be inserted and can be attached to the outer shell. A grounding portion that abuts on the upper end is provided (for example, Patent Document 1).

特開２００９−２２２２２３JP2009-222223A

アウターシェルは、ロッドガイドをアウターシェル内に固定するために、管端部を内側に加締めて湾曲形成される肩部を備えており、バンプストッパの装着時にバンプストッパの接地部とアウターシェルの肩部の上面が当接する。バンプストッパは、底部が緩衝器の最収縮時にバンプクッションラバーと突き当たりクッション荷重を受けるため、バンプストッパの接地部は肩部の上面に当接させる必要がある。また、筒部に設けられた突起部は、アウターシェルの側部を緊迫してアウターシェルに装着される。   The outer shell has a shoulder that is curved by crimping the tube end inward to fix the rod guide in the outer shell. The upper surface of the shoulder abuts. Since the bump stopper contacts the bump cushion rubber when the bottom portion of the bump stopper is contracted most, the bump stopper receives a cushion load. Therefore, the ground contact portion of the bump stopper needs to be in contact with the upper surface of the shoulder portion. Further, the protrusion provided on the cylindrical portion is attached to the outer shell by pressing the side portion of the outer shell.

ここで、アウターシェルがバンプストッパに挿入されると、突起部間隔が広げられるため、突起部と底部の境の形状が急激に変化する部分に応力が集中するため、当該部分が疲労しやすくなる。そのため、従来のバンプストッパでは、筒部と底部の境に湾曲面を設けて形状の変化を滑らかにし、応力集中を極力避けるようにしている。   Here, when the outer shell is inserted into the bump stopper, the interval between the protrusions is widened, so that stress concentrates on the part where the shape of the boundary between the protrusion and the bottom changes rapidly, so that the part is easily fatigued. . Therefore, in the conventional bump stopper, a curved surface is provided at the boundary between the cylindrical portion and the bottom portion to smooth the change in shape and to avoid stress concentration as much as possible.

しかしながら、バンプストッパの接地部と突起部はどちらもアウターシェルに当接する必要がある上、従来のバンプストッパにあっては軸方向視で接地部と突起部が周方向に同じ位置に配設されている。そのため、接地部と突起部の境の曲率半径を大きくするとアウターシェルの肩部と干渉するので、接地部と突起部の境の湾曲部の曲率半径を大きくするにも限界がある。   However, both the grounding portion and the protruding portion of the bump stopper need to contact the outer shell, and in the conventional bump stopper, the grounding portion and the protruding portion are disposed at the same position in the circumferential direction when viewed in the axial direction. ing. Therefore, if the radius of curvature at the boundary between the grounding portion and the protrusion is increased, it interferes with the shoulder of the outer shell, so there is a limit to increasing the radius of curvature of the curved portion at the boundary between the grounding portion and the protrusion.

つまり、接地部と突起部との境は、アウターシェルの肩部の角に対向しており、肩部の角は加締め加工により湾曲面とされて前記境の部分から逃げて僅かに両者の間に隙間ができるが、境の湾曲面の曲率半径を大きくすると干渉するので大きくできない。   In other words, the boundary between the grounding portion and the projecting portion is opposed to the corner of the shoulder of the outer shell, and the corner of the shoulder is curved by caulking to escape from the boundary portion and slightly There is a gap in between, but if the radius of curvature of the curved surface of the border is increased, it cannot be increased because of interference.

そこで、本発明は底部と筒部の境の曲率半径を従来のバンプストッパに比べて大きくし、応力の集中を抑制して耐久性を向上させたバンプストッパとこのバンプストッパを備える緩衝器の提供を目的とする。   Therefore, the present invention provides a bump stopper that has a larger radius of curvature at the boundary between the bottom and the cylinder than a conventional bump stopper, suppresses stress concentration, and improves durability, and a shock absorber including the bump stopper. With the goal.

前記課題を解決するための手段は、有底筒状のバンプストッパの底部に周方向に並べて設けられた接地部と、筒部に設けられた突起部を備え、前記突起部が前記接地部間に周方向に交互に配置されることを特徴とする。この構成によると、接地部と突起部が軸方向視で同一線上に設けられていないため、接地部と筒部との境に設けられる第一湾曲面と、突起部と底部との境に設けられる第二湾曲面の曲率半径を大きく設定できる。   Means for solving the problems includes a grounding portion arranged in the circumferential direction on the bottom of a bottomed cylindrical bump stopper, and a projection provided on the cylindrical portion, and the projection is between the grounding portions. Are alternately arranged in the circumferential direction. According to this configuration, since the grounding portion and the protruding portion are not provided on the same line as viewed in the axial direction, the first curved surface provided at the boundary between the grounding portion and the cylindrical portion and the boundary between the protruding portion and the bottom portion are provided. The radius of curvature of the second curved surface can be set large.

また、前記底部から前記第二湾曲面の高さを、前記底部から前記接地部の高さよりも、低いようにしてもよい。この構成によると、アウターシェルの挿入時に、アウターシェルが接地部の設けられていない第二湾曲面には干渉しないため、バンプストッパが、アウターシェルに対して傾かずに装着できる。   Further, the height of the second curved surface from the bottom may be lower than the height of the grounding portion from the bottom. According to this configuration, when the outer shell is inserted, the outer shell does not interfere with the second curved surface where the grounding portion is not provided, so that the bump stopper can be mounted without being inclined with respect to the outer shell.

また、軸方向視で前記突起部と前記接地部との間に周方向に隙間を設けるようにしてもよい。この構成によると、突起部と接地部の周方向隙間からバンプストッパ内に侵入した泥水や塵などの侵入物を排出できる。   Moreover, you may make it provide a clearance gap between the said protrusion part and the said grounding part in the circumferential direction seeing axially. According to this configuration, invading substances such as muddy water and dust that have entered the bump stopper from the circumferential gap between the protrusion and the grounding portion can be discharged.

また、前記接地部は、前記筒部の外周側に向けて広がる扇形に形成されてもよい。この構成によると、アウターシェルの上端が当接する接地部の外周側のみ幅が広くなるため、アウターシェルに当接しない先端側の材料費を削減すると共に、バンプストッパを軽量化できる。また、接地部の先端側は、接地部全体の強度を向上する補強リブとして機能し、底部の補強もできる。   Moreover, the said grounding part may be formed in the fan shape extended toward the outer peripheral side of the said cylinder part. According to this configuration, since the width is increased only on the outer peripheral side of the grounding portion with which the upper end of the outer shell contacts, the material cost on the front end side that does not contact the outer shell can be reduced, and the bump stopper can be reduced in weight. Further, the tip side of the grounding portion functions as a reinforcing rib that improves the strength of the entire grounding portion, and the bottom portion can be reinforced.

また、前記接地部が、前記底部に設けられた孔の外周まで延びて形成されてもよい。この構成によると、接地部が底部の内周側にも設けられて補強部材として機能し、底部を補強できる。   The grounding portion may be formed to extend to the outer periphery of the hole provided in the bottom portion. According to this configuration, the grounding portion is also provided on the inner peripheral side of the bottom portion, functions as a reinforcing member, and the bottom portion can be reinforced.

また、上述したバンプストッパを備える緩衝器としてもよい。この構成によると、上記効果を備える緩衝器を提供できる。   Moreover, it is good also as a buffer provided with the bump stopper mentioned above. According to this structure, the shock absorber provided with the said effect can be provided.

本発明のバンプストッパによれば、底部と筒部の境の曲率半径を大きくできるため、底部と筒部の境にかかる応力の集中を抑制して、バンプストッパの耐久性を向上できる。また、このバンプストッパを緩衝器に用いれば、緩衝器の収縮時にバンプストッパの底部にバンプクッションラバーが突き当たってクッション荷重を受ける際にも、底部と筒部の境に応力が集中するのを抑制できる。   According to the bump stopper of the present invention, since the radius of curvature at the boundary between the bottom portion and the cylinder portion can be increased, the concentration of stress applied to the boundary between the bottom portion and the cylinder portion can be suppressed, and the durability of the bump stopper can be improved. In addition, if this bump stopper is used as a shock absorber, even when the bump cushion rubber hits the bottom of the bump stopper and receives a cushion load when the shock absorber contracts, it suppresses stress concentration at the boundary between the bottom and the cylinder. it can.

本実施の形態に係るパンプストッパを装着した緩衝器を示す縦断面図である。It is a longitudinal cross-sectional view which shows the buffer equipped with the pump stopper which concerns on this Embodiment. 図１の緩衝器のアウターシェルにバンプストッパが装着された部分を拡大して示す縦断面図である。It is a longitudinal cross-sectional view which expands and shows the part by which the bump stopper was mounted | worn with the outer shell of the shock absorber of FIG. 本実施の形態に係るバンプストッパの全体を示す斜視図である。It is a perspective view which shows the whole bump stopper which concerns on this Embodiment. 本実施の形態に係るバンプストッパを示す底面図である。It is a bottom view which shows the bump stopper which concerns on this Embodiment. 図４をＸ−Ｏ−Ｙで切り取った縦断面図であって、図中右側が接地面の断面が見えるＸ−Ｏ断面で、図中左側が突起部の断面が見えるＯ−Ｙ断面を示している。FIG. 4 is a longitudinal cross-sectional view taken along X-O-Y of FIG. 4, where the right side in the drawing is a cross-sectional view of the ground plane and the left side of FIG. 4 is a cross-sectional view of the protruding portion. ing.

以下に、図示した本実施の形態に基づいて、図面を参照しながら説明する。いくつかの図面を通して付された同じ符号は、同じ部品か対応する部品を示す。   Below, based on this illustrated embodiment, it demonstrates, referring drawings. The same reference numerals given throughout the several drawings indicate the same or corresponding parts.

図１、図２に示すように本実施の形態に係るバンプストッパＳは車両の車体と車軸との間に介装されて車体の振動を抑制する緩衝器１０に用いられる。本実施の形態に係る緩衝器１０は、図１、図２に示すように、有底筒状のアウターシェル１１と、アウターシェル１１内に収容されるシリンダ１２と、シリンダ１２の開口端に設けられて、シリンダ１２内を閉塞する環状のロッドガイド１４と、ロッドガイド１４のガイド孔１４ａに挿入され、シリンダ１２内を摺動自在に移動するロッド１３を備えている。   As shown in FIGS. 1 and 2, the bump stopper S according to the present embodiment is used in a shock absorber 10 that is interposed between a vehicle body and an axle of the vehicle and suppresses vibrations of the vehicle body. As shown in FIGS. 1 and 2, the shock absorber 10 according to the present embodiment is provided at the bottomed cylindrical outer shell 11, the cylinder 12 accommodated in the outer shell 11, and the opening end of the cylinder 12. Thus, an annular rod guide 14 that closes the inside of the cylinder 12 and a rod 13 that is inserted into the guide hole 14 a of the rod guide 14 and moves slidably in the cylinder 12 are provided.

さらに、ロッド１３は下端に、シリンダ１２の内周面に摺接するピストン１５を保持しており、ピストン１５は、シリンダ１２内を作動流体が充填されるロッド側室Ｒ１とシリンダ側室Ｒ２の二つの部屋に区画している。また、アウターシェル１１とシリンダ１２の間にはリザーバ室Ｒ３が形成されており、このリザーバ室Ｒ３には作動流体と気体が充填されている。   Furthermore, the rod 13 holds a piston 15 slidably in contact with the inner peripheral surface of the cylinder 12 at the lower end. The piston 15 has two chambers, a rod side chamber R1 and a cylinder side chamber R2 filled with working fluid. It is divided into. A reservoir chamber R3 is formed between the outer shell 11 and the cylinder 12, and the reservoir chamber R3 is filled with working fluid and gas.

ピストン１５は、ロッド側室Ｒ１からシリンダ側室Ｒ２へ向かう作動流体の通過のみを許容してこの作動流体の流れに抵抗を与える減衰弁１６と、シリンダ側室Ｒ２からロッド側室Ｒ１へ向かう作動流体の通過のみを許容するチェック弁１７を備えている。   The piston 15 permits only the passage of the working fluid from the rod side chamber R1 to the cylinder side chamber R2, and provides resistance to the flow of the working fluid, and only the passage of the working fluid from the cylinder side chamber R2 to the rod side chamber R1. Is provided with a check valve 17 that permits

シリンダ１２の下端には、シリンダ側室Ｒ２とリザーバ室Ｒ３を区画するバルブケース２０が嵌合されている。バルブケース２０は、シリンダ側室Ｒ２からリザーバ室Ｒ３へ向かう作動流体の通過のみを許容して作動流体の流れに抵抗を与えるベースバルブ２１と、リザーバ室Ｒ３からシリンダ側室Ｒ２へ向かう作動流体の通過のみを許容するチェック弁２２とを備えている。   A valve case 20 that divides the cylinder side chamber R2 and the reservoir chamber R3 is fitted to the lower end of the cylinder 12. The valve case 20 allows only the passage of the working fluid from the cylinder side chamber R2 to the reservoir chamber R3 and provides resistance to the flow of the working fluid, and only the passage of the working fluid from the reservoir chamber R3 to the cylinder side chamber R2. Is provided.

緩衝器１０の伸長時にロッド１３がシリンダ１２から退出する場合には、縮小されるロッド側室Ｒ１から、作動流体が減衰弁１６を介して拡大されるシリンダ側室Ｒ２に移動する際に、減衰弁１６が作動流体の流れに抵抗を与えて減衰力が発生される。   When the rod 13 is retracted from the cylinder 12 when the shock absorber 10 is extended, the damping valve 16 is moved when the working fluid moves from the rod side chamber R1 to be reduced through the damping valve 16 to the cylinder side chamber R2. Gives resistance to the flow of the working fluid, and a damping force is generated.

反対に緩衝器１０の収縮時にロッド１３がシリンダ１２内に侵入する場合には、ロッド侵入体積分だけ過剰になった作動流体がベースバルブ２１を介してリザーバ室Ｒ３に排出される際、ベースバルブ２１が作動流体の流れに抵抗を与えて減衰力が発生される。   On the other hand, when the rod 13 enters the cylinder 12 when the shock absorber 10 is contracted, when the working fluid that has exceeded the rod intruding volume is discharged to the reservoir chamber R3 via the base valve 21, the base valve 21 gives resistance to the flow of the working fluid and a damping force is generated.

なお、本実施の形態においては、緩衝器１０は、アウターシェル１１とシリンダ１２を備える複筒型になっているが、単筒型の緩衝器になっていてもよい。   In the present embodiment, the shock absorber 10 is a double cylinder type including the outer shell 11 and the cylinder 12, but may be a single cylinder type shock absorber.

また、図２に示すように、本実施の形態に係る緩衝器１０では、シリンダ１２の上端に設けられたロッドガイド１４に環状のオイルシール１５が積層されている。そして、オイルシール１５がロッドガイド１４に積層された状態でアウターシェル１１の開口側端部を内側に折り曲げて加締めて形成された加締め部１１ａで、ロッドガイド１４及びオイルシール１５をアウターシェル１１とシリンダ１２の間に固定している。   As shown in FIG. 2, in the shock absorber 10 according to the present embodiment, an annular oil seal 15 is laminated on a rod guide 14 provided at the upper end of the cylinder 12. Then, the rod guide 14 and the oil seal 15 are connected to the outer shell by a crimping portion 11a formed by bending the opening side end portion of the outer shell 11 inward with the oil seal 15 being laminated on the rod guide 14. 11 and the cylinder 12 are fixed.

このオイルシール１５は内周径がロッド１３の外周径よりも小さくなっているため、オイルシール１５がロッド１３の外周を密にシールし、ロッド１３がシリンダ１２内を出没する際にシリンダ内から作動流体が外に漏れ出てしまうのを阻止する。   Since the inner diameter of the oil seal 15 is smaller than the outer diameter of the rod 13, the oil seal 15 tightly seals the outer periphery of the rod 13, and when the rod 13 moves in and out of the cylinder 12, Prevents working fluid from leaking out.

また、ロッド１３の上端側外周には弾性部材で形成され、緩衝器１０の最収縮時にアウターシェル１１の上端に装着されて設けられたバンプストッパＳと当接し弾性変形して緩衝器の最収縮時の衝撃を緩和するバンプクッションラバー１９が設けられている。   The rod 13 is formed of an elastic member on the outer periphery on the upper end side, abuts against the bump stopper S provided on the upper end of the outer shell 11 when the shock absorber 10 is contracted most, and elastically deforms to contract the shock absorber. A bump cushion rubber 19 is provided to alleviate the impact at the time.

本実施の形態に係るバンプストッパＳは、有底筒状であって、図１、２に示すようにアウターシェル１１の上端に装着されている。バンプストッパＳの材質は特に限定されないが、たとえば合成樹脂で形成される。   The bump stopper S according to the present embodiment has a bottomed cylindrical shape and is attached to the upper end of the outer shell 11 as shown in FIGS. The material of the bump stopper S is not particularly limited, but is formed of, for example, a synthetic resin.

以下、バンプストッパＳについて具体的に説明する。バンプストッパＳの有底筒状の本体１は、図３に示すように、筒部２と筒部２の一方側開口に連結された環状の底部３を備えてなる。   Hereinafter, the bump stopper S will be described in detail. As shown in FIG. 3, the bottomed cylindrical main body 1 of the bump stopper S includes a cylindrical portion 2 and an annular bottom portion 3 connected to one side opening of the cylindrical portion 2.

底部３は、ロッド１３を挿通可能な大きさの貫通孔３ａを有して環状とされ、内周側には図３、図４に示すように、突状の接地部５が貫通孔３ａの周りに周方向に間隔をあけて並べて設けられている。また、緩衝器１０の最収縮時にバンプクッションラバー１９がバンプストッパＳに突き当たる際に荷重を受けるために、接地部５はアウターシェル１１に装着する際に、アウターシェル１１の上端に形成された加締め部１１ａの上端に当接する。   The bottom portion 3 has a through hole 3a of a size that allows the rod 13 to be inserted into an annular shape. As shown in FIGS. 3 and 4, a projecting grounding portion 5 is formed on the inner peripheral side of the through hole 3a. It is arranged around the periphery at intervals in the circumferential direction. Further, since the bump cushion rubber 19 receives a load when it strikes the bump stopper S when the shock absorber 10 is most contracted, the grounding portion 5 is added to the upper end of the outer shell 11 when mounted on the outer shell 11. It contacts the upper end of the fastening part 11a.

本実施の形態に係る接地部５は、図４に示すように、外周が筒部２に連なり、底部３の外周側に向けて広がる扇形に形成されている。ここで、加締め部１１ａは、ロッド１３に対し間隔をあけて設けられていて、接地部５の外周側のみに加締め部１１ａの上端が当接する。そのため、接地部５は加締め部１１ａに当接する範囲で設ければよいので、底部３の外周部にのみ設けられていれば足りる。しかしながら、底部３は緩衝器１０の最収縮時にバンプクッションラバー１９から荷重を受ける。そのため、本実施の形態に係る接地部５を貫通孔３ａまで延長される扇形にすると、アウターシェル１１の加締め部１１ａと当接しない先端部分が、接地部５全体の強度を向上する補強リブとして機能する。   As shown in FIG. 4, the grounding portion 5 according to the present embodiment is formed in a fan shape whose outer periphery is continuous with the cylindrical portion 2 and extends toward the outer peripheral side of the bottom portion 3. Here, the caulking portion 11 a is provided at a distance from the rod 13, and the upper end of the caulking portion 11 a abuts only on the outer peripheral side of the grounding portion 5. For this reason, it is sufficient that the grounding portion 5 is provided in a range where it comes into contact with the caulking portion 11 a, so that it is sufficient if it is provided only on the outer peripheral portion of the bottom portion 3. However, the bottom 3 receives a load from the bump cushion rubber 19 when the shock absorber 10 is most contracted. Therefore, when the grounding portion 5 according to the present embodiment is formed in a fan shape that extends to the through hole 3a, the tip portion of the outer shell 11 that does not contact the caulking portion 11a improves the strength of the entire grounding portion 5. Function as.

また、図５に示すように、本実施の形態では接地部５の幅狭側の先端を貫通孔３ａ側に傾斜させて徐々に薄くしながら貫通孔３ａの外周縁まで延びるように形成して、補強効果を得つつバンプストッパＳの軽量化を図り、材料費を削減している。ただし、接地部５の幅狭側の先端を傾斜させずに貫通孔３ａの外周縁まで延びるようにして、補強効果をより高めるようにしてもよい。   Further, as shown in FIG. 5, in the present embodiment, the narrow end of the grounding portion 5 is inclined toward the through hole 3a so as to be gradually thinned so as to extend to the outer peripheral edge of the through hole 3a. The bump stopper S is reduced in weight while obtaining a reinforcing effect, and the material cost is reduced. However, the reinforcing effect may be further enhanced by extending to the outer peripheral edge of the through hole 3a without inclining the narrow end of the grounding portion 5.

また、接地部５には、中心に内周側を頂点とした三角状の肉抜き用の溝３ｂが設けられており、バンプストッパＳの軽量化を図ると共に材料費を削減している。本実施の形態においては、肉抜き用の溝３ｂは、接地部５を扇形にしているため、溝３ｂから接地部５の外縁までの肉厚を変えず、接地部５に強度が弱くなる箇所ができないように三角状にしているが、形状は特に限定されない。   In addition, the grounding portion 5 is provided with a triangular-shaped thinning groove 3b with the inner peripheral side at the center in the center, thereby reducing the weight of the bump stopper S and reducing the material cost. In the present embodiment, since the grounding groove 3b has a fan-shaped grounding portion 5, the thickness from the groove 3b to the outer edge of the grounding portion 5 is not changed, and the strength of the grounding portion 5 is weakened. However, the shape is not particularly limited.

筒部２は、図３、図４に示すように、底部３に設けられた接地部５と周方向に交互に設けられると共に、筒部２の軸方向に延びてリブ状に形成され、筒部２の内側に突出する突起部６を有する。さらに、突起部６の図中下側は下方に行くにしたがって拡径するテーパー状になっている。   As shown in FIGS. 3 and 4, the cylindrical portion 2 is provided alternately with the grounding portions 5 provided on the bottom portion 3 in the circumferential direction, and extends in the axial direction of the cylindrical portion 2 and is formed in a rib shape. The protrusion 2 protrudes inside the portion 2. Furthermore, the lower side of the protrusion 6 in the drawing is tapered such that its diameter increases as it goes downward.

この際、突起部６は、アウターシェル１１の外径よりも筒部２の内径が小さくなる程度に内側に突出していればよい。また、突起部６と接地部５の間には軸方向視で、隙間１ａが形成されており、パンプストッパＳ内に侵入した泥水や塵などを外に排出する排出通路として機能する。   At this time, the protruding portion 6 only needs to protrude inward so that the inner diameter of the cylindrical portion 2 becomes smaller than the outer diameter of the outer shell 11. Further, a gap 1a is formed between the projection 6 and the grounding portion 5 in the axial direction, and functions as a discharge passage for discharging muddy water, dust and the like that have entered the pump stopper S to the outside.

また、本実施の形態に係るバンプストッパＳは、底部３の接地部５と筒部２の突起部６とが周方向に交互に設けられているため、接地部５は突起部６が設けられていない筒部２と連結され、突起部６は接地部５が設けられていない底部３と連結されている。さらに、図５に示すように、接地部５と筒部２との境には断面形状変化を緩和する第一湾曲面Ｃ１が設けられ、突起部６と底部３との境にも同様に断面形状変化を緩和する第二湾曲面Ｃ２が設けられている。   Further, in the bump stopper S according to the present embodiment, since the grounding portion 5 of the bottom portion 3 and the protruding portion 6 of the cylindrical portion 2 are alternately provided in the circumferential direction, the grounding portion 5 is provided with the protruding portion 6. The protruding portion 6 is connected to the bottom portion 3 where the grounding portion 5 is not provided. Further, as shown in FIG. 5, a first curved surface C <b> 1 is provided at the boundary between the grounding portion 5 and the cylindrical portion 2 to relieve the change in cross-sectional shape. A second curved surface C2 is provided to relieve the shape change.

次に、図２を用いてアウターシェル１１の上端にバンプストッパＳが装着される過程と、装着状態について説明する。   Next, the process of mounting the bump stopper S on the upper end of the outer shell 11 and the mounting state will be described with reference to FIG.

バンプストッパＳの筒部２に設けられる突起部６は、本実施例では６個設けられていて、軸方向視で突起部６の内周面を通る円の直径は、アウターシェル１１の外径よりも小さくなるように形成されている。そのため、アウターシェル１１をバンプストッパＳに挿入すると、バンプストッパＳが押し広げられるため、突起部６がアウターシェル１１を緊迫してバンプストッパＳをアウターシェル１１に固定できる。また、突起部６の下端側はテーパー状になっているため、アウターシェル１１の挿入を案内して、スムーズに挿入できる。   In the present embodiment, six protrusions 6 provided on the cylindrical portion 2 of the bump stopper S are provided, and the diameter of a circle passing through the inner peripheral surface of the protrusion 6 in the axial direction is the outer diameter of the outer shell 11. It is formed to be smaller than that. For this reason, when the outer shell 11 is inserted into the bump stopper S, the bump stopper S is pushed and spread, so that the protrusion 6 can press the outer shell 11 and fix the bump stopper S to the outer shell 11. Moreover, since the lower end side of the projection part 6 is tapered, the insertion of the outer shell 11 can be guided and inserted smoothly.

図２に示すように、バンプストッパＳは、アウターシェル１１の上端に設けられた加締め部１１ａが底部３の接地部５に当接するまで押し込まれ、アウターシェル１１の側部が筒部２の突起部６に押し当てられて装着される。   As shown in FIG. 2, the bump stopper S is pushed in until the caulking portion 11 a provided at the upper end of the outer shell 11 contacts the grounding portion 5 of the bottom portion 3, and the side portion of the outer shell 11 is the cylindrical portion 2. It is pressed against the protrusion 6 and attached.

ここで、第一湾曲面Ｃ１は、接地部５と筒部２との境に設けられた湾曲面であるため、図２に示すように、第一湾曲面Ｃ１では、アウターシェル１１の加締め部１１ａの上端が接地部５に当接し、突起部６の設けられていない筒部２には当接しない。つまり、接地部５とアウターシェル１１は当接しているが、筒部２とアウターシェル１１との間には接地部５の肉厚分の隙間ができる。これにより、筒部２と加締め部１１ａとの間には径方向に大きなスペースが確保される。   Here, since the first curved surface C1 is a curved surface provided at the boundary between the grounding portion 5 and the cylindrical portion 2, the first curved surface C1 is caulked with the outer shell 11 as shown in FIG. The upper end of the portion 11a abuts on the grounding portion 5 and does not abut on the cylindrical portion 2 on which the protrusion 6 is not provided. That is, although the grounding portion 5 and the outer shell 11 are in contact with each other, a gap corresponding to the thickness of the grounding portion 5 is formed between the cylindrical portion 2 and the outer shell 11. Thereby, a large space in the radial direction is ensured between the tube portion 2 and the caulking portion 11a.

そのため、突起部６が軸方向視で接地部５と同じ位置に設けられていた従来のバンプストッパに比べて、アウターシェル１１と筒部２との間に設けられた径方向のスペースの分だけ外側に膨らませて第一湾曲面Ｃ１の曲率半径を大きくできる。   Therefore, as compared with the conventional bump stopper in which the protruding portion 6 is provided at the same position as the grounding portion 5 in the axial view, only a radial space provided between the outer shell 11 and the cylindrical portion 2 is provided. The radius of curvature of the first curved surface C1 can be increased by inflating outward.

他方、第二湾曲面Ｃ２は、突起部６と底部３との境に設けられた湾曲面であるため、図２に示すように、第二湾曲面Ｃ２では、アウターシェル１１の側部が突起部６に緊迫され、接地部５の設けられていない底部３には当接しない。つまり、突起部６とアウターシェル１１は当接しているが、底部３とアウターシェル１１との間には突起部６の肉厚分の隙間ができる。これにより、突起部６と加締め部１１ａとの間には軸方向に大きなスペースが確保される。   On the other hand, since the second curved surface C2 is a curved surface provided at the boundary between the protruding portion 6 and the bottom portion 3, the side portion of the outer shell 11 protrudes on the second curved surface C2, as shown in FIG. It is pressed by the part 6 and does not contact the bottom part 3 where the grounding part 5 is not provided. That is, although the protrusion 6 and the outer shell 11 are in contact with each other, a gap corresponding to the thickness of the protrusion 6 is formed between the bottom 3 and the outer shell 11. Thereby, a large space is ensured in the axial direction between the protrusion 6 and the caulking portion 11a.

そのため、接地部５が軸方向視で突起部６と同じ位置に設けられていた従来のバンプストッパに比べて、アウターシェル１１と底部３との間に設けられた軸方向のスペースの分だけ上側に膨らませて第二湾鏡面Ｃ２の曲率半径を大きくできる。   Therefore, compared to the conventional bump stopper in which the grounding portion 5 is provided at the same position as the protruding portion 6 when viewed in the axial direction, it is higher by the axial space provided between the outer shell 11 and the bottom portion 3. The radius of curvature of the second bay mirror surface C2 can be increased.

このようにすると、アウターシェル１１がバンプストッパＳに圧入され、第一湾曲面Ｃ１と第二湾曲面Ｃ２を支点にして筒部２が押し広げられるが、第一湾曲面Ｃ１と第二湾曲面Ｃ２の曲率半径を大きくできるため、湾曲面がなだらかになり、応力集中を抑制できる。   In this way, the outer shell 11 is press-fitted into the bump stopper S, and the cylindrical portion 2 is pushed and spread around the first curved surface C1 and the second curved surface C2, but the first curved surface C1 and the second curved surface Since the radius of curvature of C2 can be increased, the curved surface becomes smooth and stress concentration can be suppressed.

また、緩衝器１０が収縮されてバンプクッションラバー１９とバンプストッパＳの上端面が当接すると、第一湾曲面Ｃ１と第二湾曲面Ｃ２に内向きの応力が働くが、第一湾曲面Ｃ１と第二湾曲面Ｃ２の曲率半径を大きくできるため、応力集中を抑制できる。   Further, when the shock absorber 10 is contracted and the bump cushion rubber 19 and the upper end surface of the bump stopper S come into contact, inward stress acts on the first curved surface C1 and the second curved surface C2, but the first curved surface C1. Since the radius of curvature of the second curved surface C2 can be increased, stress concentration can be suppressed.

また、図２に示すように、底部３から第二湾曲面Ｃ２の高さは、底部３から接地部５の高さよりも低く設定されているため、アウターシェル１１がバンプストッパＳ内に挿入される際に第二湾曲面Ｃ２がアウターシェル１１の上端に干渉しない。   2, the height of the second curved surface C2 from the bottom 3 is set lower than the height of the grounding portion 5 from the bottom 3, so that the outer shell 11 is inserted into the bump stopper S. The second curved surface C2 does not interfere with the upper end of the outer shell 11.

以下、本実施の形態に係るバンプストッパＳの効果について説明する。   Hereinafter, the effect of the bump stopper S according to the present embodiment will be described.

本実施の形態に係るバンプストッパＳは、アウターシェル１１が挿入される有底筒状の本体１と、本体１の底部３に設けた貫通孔３ａの周りに周方向に並べて設けたアウターシェル１１の上端に当接する突状の接地部５と、本体１の筒部２の内周に軸方向視で接地部５間に配置され、アウターシェル１１の側部に押し当てられる突起部６と、接地部５と筒部２との境に設けられる第一湾曲面Ｃ１と、突起部６と底部３との境に設けられる第二湾曲面Ｃ２を備えてなる。この構成によると、バンプストッパＳの底部３と筒部２の境の曲率半径を全周にわたって大きくできる。そのため、アウターシェル１１の挿入時、底部３と筒部２の境にかかる応力と緩衝器１０の最収縮時にバンプクッションラバー１９との接触によって底部３と筒部２の境にかかる応力の集中を抑制できる。よって、バンプストッパＳの耐久性を向上させる。   The bump stopper S according to the present embodiment includes a bottomed cylindrical main body 1 into which the outer shell 11 is inserted, and an outer shell 11 provided side by side in the circumferential direction around a through-hole 3a provided in the bottom 3 of the main body 1. A projecting grounding portion 5 that abuts on the upper end of the main body 1, a projecting portion 6 that is disposed between the grounding portions 5 on the inner periphery of the cylindrical portion 2 of the main body 1 as viewed in the axial direction, and pressed against the side of the outer shell 11 The first curved surface C1 provided at the boundary between the grounding portion 5 and the cylindrical portion 2 and the second curved surface C2 provided at the boundary between the protruding portion 6 and the bottom portion 3 are provided. According to this configuration, the radius of curvature at the boundary between the bottom 3 and the cylinder 2 of the bump stopper S can be increased over the entire circumference. Therefore, when the outer shell 11 is inserted, the stress applied to the boundary between the bottom 3 and the cylinder 2 is concentrated due to the stress applied to the boundary between the bottom 3 and the cylinder 2 due to the contact with the bump cushion rubber 19 when the shock absorber 10 is contracted. Can be suppressed. Therefore, the durability of the bump stopper S is improved.

なお、本実施の形態においては、突起部６は、軸方向視で接地部５の間にそれぞれ設けられているが、接地部５間の二つ以上に設けられていれば、アウターシェル１１の側部を押圧してバンプストッパＳを緩衝器１０に装着するには足りる。したがって、本実施の形態においては、突起部６の本数は受ける荷重、つまり車体の重量に応じて、任意の本数に設定できる。   In the present embodiment, the protrusions 6 are provided between the grounding portions 5 as viewed in the axial direction. However, if the projections 6 are provided at two or more between the grounding portions 5, the outer shell 11 It is enough to attach the bump stopper S to the shock absorber 10 by pressing the side portion. Therefore, in the present embodiment, the number of protrusions 6 can be set to an arbitrary number according to the load received, that is, the weight of the vehicle body.

また、本実施の形態においては、底部３から第二湾曲面Ｃ２の高さは、底部３から接地部５の高さよりも、低くなるように設定されている。この構成によると、アウターシェル１１の挿入時に、アウターシェル１１の上端が接地部５の設けられていない第二湾曲面Ｃ２に干渉しないため、バンプストッパＳをアウターシェル１１に対して傾かせずに装着できる。   In the present embodiment, the height from the bottom 3 to the second curved surface C2 is set to be lower than the height from the bottom 3 to the grounding portion 5. According to this configuration, when the outer shell 11 is inserted, since the upper end of the outer shell 11 does not interfere with the second curved surface C2 where the grounding portion 5 is not provided, the bump stopper S is not inclined with respect to the outer shell 11. Can be installed.

また、本実施の形態においては、軸方向視で突起部６と接地部５との間に周方向に隙間１ａを設けている。この構成によると、バンプストッパＳ内に泥水や塵が侵入した際に、隙間１ａが排出流路として機能する。   In the present embodiment, a gap 1a is provided in the circumferential direction between the protrusion 6 and the grounding portion 5 when viewed in the axial direction. According to this configuration, when muddy water or dust enters the bump stopper S, the gap 1a functions as a discharge channel.

また、接地部５は、筒部２の外周側に向けて広がる扇形に形成されてなる。この構成によると、アウターシェル１１上端に形成される加締め部１１ａの上端が当接する接地部５の外周を大きく、加締め部１１ａが当接しない内周側を小さくでき、バンプストッパＳの軽量化と材料費の削減ができる。また、加締め部１１ａと当接しない接地部５の先端部分は、底部３の補強リブとして機能し、底部３の耐久性を向上できる。   The grounding portion 5 is formed in a fan shape that spreads toward the outer peripheral side of the cylindrical portion 2. According to this configuration, the outer periphery of the grounding portion 5 with which the upper end of the crimping portion 11a formed at the upper end of the outer shell 11 abuts can be increased, and the inner peripheral side with which the crimping portion 11a does not abut can be reduced. And material costs can be reduced. Moreover, the front-end | tip part of the grounding part 5 which is not contact | abutted with the crimping part 11a functions as a reinforcement rib of the bottom part 3, and can improve the durability of the bottom part 3.

また、接地部５が、底部３に設けられた貫通孔３ａの外周まで延びて形成されている。この構成によると、接地部５がアウターシェル１１の上端を受けるだけでなく、底部３の補強部材としても機能し、バンプクッションラバー１９が底部３に突き当てられる際の衝撃に対して耐久性を向上できる。   The grounding portion 5 is formed to extend to the outer periphery of the through hole 3 a provided in the bottom portion 3. According to this configuration, the grounding portion 5 not only receives the upper end of the outer shell 11, but also functions as a reinforcing member for the bottom portion 3, and is durable against an impact when the bump cushion rubber 19 is abutted against the bottom portion 3. It can be improved.

以上、本発明の好ましい実施の形態を詳細に説明したが、特許請求の範囲から逸脱なく改造、変形及び変更ができるのは当然である。   Although the preferred embodiments of the present invention have been described in detail above, it is obvious that modifications, changes and modifications can be made without departing from the scope of the claims.

１・・・本体、１ａ・・・隙間、２・・・筒部、３・・・底部、３ａ・・・貫通孔、５・・・接地部、６・・・突起部、１０・・・緩衝器、１１・・・アウターシェル、Ｃ１・・・第一湾曲部、Ｃ２・・・第二湾曲部、Ｓ・・・バンプストッパ
DESCRIPTION OF SYMBOLS 1 ... Main body, 1a ... Gap, 2 ... Tube part, 3 ... Bottom part, 3a ... Through-hole, 5 ... Grounding part, 6 ... Projection part, 10 ... Shock absorber, 11 ... outer shell, C1 ... first curved portion, C2 ... second curved portion, S ... bump stopper

Claims (6)

アウターシェルが挿入される有底筒状の本体と、
前記本体の底部に設けた貫通孔の周りに周方向に並べて設けた前記アウターシェルの上端に当接する突状の接地部と、
前記本体の筒部の内周に、軸方向視で前記接地部間の二つ以上に配置され、前記アウターシェルの側部に押し当てられる突起部と、
前記接地部と前記筒部との境に設けられる第一湾曲面と、
前記突起部と前記底部との境に設けられる第二湾曲面を備えることを特徴とするバンプストッパ。 A bottomed cylindrical body into which the outer shell is inserted;
A projecting grounding portion that comes into contact with the upper end of the outer shell arranged in a circumferential direction around a through hole provided in the bottom of the main body;
On the inner periphery of the cylindrical portion of the main body, two or more between the grounding portions as viewed in the axial direction, and a protrusion that is pressed against the side portion of the outer shell,
A first curved surface provided at a boundary between the grounding portion and the cylindrical portion;
A bump stopper comprising a second curved surface provided at a boundary between the protrusion and the bottom. 前記底部から前記第二湾曲面の高さは、前記底部から前記接地部の高さよりも、低いことを特徴とする請求項１に記載のバンプストッパ。   The bump stopper according to claim 1, wherein a height of the second curved surface from the bottom portion is lower than a height of the grounding portion from the bottom portion. 軸方向視で前記突起部と前記接地部との間に周方向に隙間を設けたことを特徴とする請求項１または２に記載のバンプストッパ。   The bump stopper according to claim 1, wherein a gap is provided in a circumferential direction between the protrusion and the grounding portion when viewed in the axial direction. 前記接地部は、前記筒部の外周側に向けて広がる扇形に形成されることを特徴とする請求項１から３のいずれか一項に記載のバンプストッパ。   The bump stopper according to any one of claims 1 to 3, wherein the grounding portion is formed in a fan shape that spreads toward an outer peripheral side of the cylindrical portion. 前記接地部が、前記底部に設けられた貫通孔の外周まで延びて形成されることを特徴とする請求項１から４のいずれか一項に記載のバンプストッパ。   The bump stopper according to any one of claims 1 to 4, wherein the grounding portion is formed to extend to an outer periphery of a through hole provided in the bottom portion. 請求項１から５のいずれか一項に記載のバンプストッパを備えることを特徴とする緩衝器。
A bumper comprising the bump stopper according to any one of claims 1 to 5.
JP2015142280A 2015-07-16 2015-07-16 Bump stopper and buffer Pending JP2017025950A (en)

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WO2020044651A1 (en) * 2018-08-29 2020-03-05 Ｋｙｂ株式会社 Bump stopper, damper, and method for manufacturing bump stopper

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