JP7103722B2

JP7103722B2 - Shock absorber

Info

Publication number: JP7103722B2
Application number: JP2018178453A
Authority: JP
Inventors: 英生長山; 道生早川
Original assignee: Hitachi Astemo Ltd
Current assignee: Hitachi Astemo Ltd
Priority date: 2018-09-25
Filing date: 2018-09-25
Publication date: 2022-07-20
Anticipated expiration: 2038-09-25
Also published as: JP2020051457A

Description

本発明は、緩衝器に関する。 The present invention relates to a shock absorber.

緩衝装置等に用いられるピストン部として、環状突部を形成したピストンリングをピストン本体に被せた構成のものがある（例えば、特許文献１参照）。 As a piston portion used for a shock absorber or the like, there is one having a configuration in which a piston ring having an annular protrusion is formed over the piston body (see, for example, Patent Document 1).

特開２００２－２７６８０８号公報JP-A-2002-276808

緩衝器においては、ピストンとシリンダとの間の摩擦特性の調整を容易化する要望があった。 In the shock absorber, there has been a demand for facilitating the adjustment of the frictional characteristics between the piston and the cylinder.

本発明は、ピストンとシリンダとの間の摩擦特性の調整を容易化することが可能となる緩衝器の提供を目的とする。 An object of the present invention is to provide a shock absorber capable of facilitating adjustment of frictional characteristics between a piston and a cylinder.

上記目的を達成するために、本発明は、ピストンバンドが、シリンダ内に配置される前の組付前状態で、最大外径部よりも先端側の先端側外周部と前記最大外径部を通る軸方向線とのなす角が、前記最大外径部よりも前記先端側外周部とは反対側の基端側外周部と前記最大外径部を通る軸方向線とのなす角よりも大きい、構成とした。 In order to achieve the above object, in the present invention, in the state before assembly before the piston band is arranged in the cylinder, the outer peripheral portion on the tip side and the maximum outer diameter portion on the tip side of the maximum outer diameter portion are formed. The angle formed by the axial line passing through is larger than the angle formed by the outer peripheral portion on the base end side opposite to the outer peripheral portion on the tip side and the axial line passing through the maximum outer diameter portion. , The composition.

また、ピストンバンドが、シリンダ内に配置される前の組付前状態で、最大外径部よりも先端側の先端側外周部と前記最大外径部を通る軸方向線とのなす角が、前記最大外径部よりも前記先端側外周部とは反対側の基端側外周部と前記最大外径部を通る軸方向線とのなす角よりも小さい、構成とした。 Further, in the pre-assembled state before the piston band is arranged in the cylinder, the angle formed by the tip-side outer peripheral portion on the tip end side of the maximum outer diameter portion and the axial line passing through the maximum outer diameter portion is The configuration is such that the angle between the base end side outer peripheral portion on the side opposite to the tip end side outer peripheral portion and the axial line passing through the maximum outer diameter portion is smaller than the maximum outer diameter portion.

本発明によれば、ピストンとシリンダとの間の摩擦特性の調整を容易化することが可能となる。 According to the present invention, it is possible to facilitate the adjustment of the frictional characteristics between the piston and the cylinder.

本発明に係る一実施形態の緩衝器を示す断面図である。It is sectional drawing which shows the shock absorber of one Embodiment which concerns on this invention. 本発明に係る一実施形態の緩衝器を示す要部の部分断面図である。It is a partial cross-sectional view of the main part which shows the shock absorber of one Embodiment which concerns on this invention. 本発明に係る一実施形態の緩衝器のピストン変位と摩擦力との関係を示すリサージュ波形図である。It is a Lissajous waveform diagram which shows the relationship between the piston displacement and the frictional force of the shock absorber of one Embodiment which concerns on this invention. 本発明に係る一実施形態の緩衝器を示す要部の部分断面図である。It is a partial cross-sectional view of the main part which shows the shock absorber of one Embodiment which concerns on this invention. 本発明に係る一実施形態の緩衝器を示す要部の部分断面図である。It is a partial cross-sectional view of the main part which shows the shock absorber of one Embodiment which concerns on this invention. 本発明に係る一実施形態の緩衝器の変形例を示す要部の部分断面図である。It is a partial cross-sectional view of the main part which shows the modification of the shock absorber of one Embodiment which concerns on this invention.

本発明に係る一実施形態の緩衝器を図面を参照して以下に説明する。 A shock absorber according to an embodiment of the present invention will be described below with reference to the drawings.

本実施形態の緩衝器１０は、自動車や鉄道車両のサスペンション装置に用いられる緩衝器である。図１に示すように、緩衝器１０は、作動流体が封入されるシリンダ１１を有している。シリンダ１１は、円筒状の内筒１２と、内筒１２よりも大径で内筒１２の外側に設けられる有底筒状の外筒１３とで構成されている。内筒１２および外筒１３の間にリザーバ室１４が形成されている。外筒１３は、軸方向一側に底部１５を有し軸方向他側が開口部１６とされており、開口部１６はシリンダ１１の開口部となっている。 The shock absorber 10 of the present embodiment is a shock absorber used in a suspension device of an automobile or a railroad vehicle. As shown in FIG. 1, the shock absorber 10 has a cylinder 11 in which a working fluid is sealed. The cylinder 11 is composed of a cylindrical inner cylinder 12 and a bottomed cylinder-shaped outer cylinder 13 having a diameter larger than that of the inner cylinder 12 and provided on the outside of the inner cylinder 12. A reservoir chamber 14 is formed between the inner cylinder 12 and the outer cylinder 13. The outer cylinder 13 has a bottom portion 15 on one side in the axial direction and an opening 16 on the other side in the axial direction, and the opening 16 is an opening of the cylinder 11.

シリンダ１１の内筒１２内には、ピストン１７が摺動可能に挿入されている。このピストン１７は、シリンダ１１の内筒１２内を一側室１８と他側室１９とに画成している。シリンダ１１内には、一側室１８および他側室１９内に作動流体としての作動液が封入され、リザーバ室１４内に作動流体としての作動液およびガスが封入される。 A piston 17 is slidably inserted into the inner cylinder 12 of the cylinder 11. The piston 17 defines the inside of the inner cylinder 12 of the cylinder 11 into a one-side chamber 18 and an other-side chamber 19. In the cylinder 11, the working fluid as the working fluid is sealed in the one side chamber 18 and the other side chamber 19, and the working fluid and the gas as the working fluid are sealed in the reservoir chamber 14.

ピストン１７には金属製のピストンロッド２０が連結されている。ピストンロッド２０は、軸方向一側の基端部２１がシリンダ１１内に挿入されており、軸方向他側の先端部２２がシリンダ１１の軸方向の一端つまり内筒１２および外筒１３の軸方向の一端よりも外部に延出されている。ピストン１７は、ピストンロッド２０の基端部２１にナット２３によって固定されており、ピストンロッド２０と一体的に移動する。 A metal piston rod 20 is connected to the piston 17. In the piston rod 20, the base end portion 21 on one side in the axial direction is inserted into the cylinder 11, and the tip end portion 22 on the other side in the axial direction is one end in the axial direction of the cylinder 11, that is, the shafts of the inner cylinder 12 and the outer cylinder 13. It extends outward from one end of the direction. The piston 17 is fixed to the base end portion 21 of the piston rod 20 by a nut 23, and moves integrally with the piston rod 20.

シリンダ１１の内側には、ピストンロッド２０が突出する外筒１３の開口部１６側に、環状のロッドガイド２５と、環状のシール部材２６とが配置されており、外筒１３の底部１５側にベースバルブ２８が設けられている。ロッドガイド２５は、言い換えれば、シリンダ１１の底部１５とは反対側に設けられている。ロッドガイド２５は、ピストンロッド２０を、その径方向の移動を規制しつつ軸方向の移動を案内する。シール部材２６は、シリンダ１１の一端の開口部１６側を閉塞して、内筒１２内の作動液およびリザーバ室１４内のガスおよび作動液が外部に漏出するのを規制する。一側室１８は、ロッドガイド２５とピストン１７との間に配置されており、その内側にピストンロッド２０が貫通するロッド側室となっている。 Inside the cylinder 11, an annular rod guide 25 and an annular seal member 26 are arranged on the opening 16 side of the outer cylinder 13 on which the piston rod 20 protrudes, and on the bottom 15 side of the outer cylinder 13. A base valve 28 is provided. In other words, the rod guide 25 is provided on the side opposite to the bottom portion 15 of the cylinder 11. The rod guide 25 guides the piston rod 20 to move in the axial direction while restricting its movement in the radial direction. The seal member 26 closes the opening 16 side of one end of the cylinder 11 to prevent the hydraulic fluid in the inner cylinder 12 and the gas and the hydraulic fluid in the reservoir chamber 14 from leaking to the outside. The one side chamber 18 is arranged between the rod guide 25 and the piston 17, and is a rod side chamber through which the piston rod 20 penetrates.

ベースバルブ２８は、そのベースボディ３１に、他側室１９とリザーバ室１４とを連通可能な液通路３２および液通路３３が形成されている。ベースボディ３１には、径方向内側の液通路３２を開閉可能なディスクバルブ３５と、径方向外側の液通路３３を開閉可能なディスクバルブ３６とが、リベット３７で取り付けられている。他側室１９は、ベースバルブ２８とピストン１７との間に配置されるボトム側室であり、その内側にピストンロッド２０は貫通していない。 The base valve 28 is formed with a liquid passage 32 and a liquid passage 33 capable of communicating the other side chamber 19 and the reservoir chamber 14 in the base body 31. A disc valve 35 capable of opening and closing the liquid passage 32 on the inner side in the radial direction and a disc valve 36 capable of opening and closing the liquid passage 33 on the outer side in the radial direction are attached to the base body 31 with rivets 37. The other side chamber 19 is a bottom side chamber arranged between the base valve 28 and the piston 17, and the piston rod 20 does not penetrate inside the bottom side chamber.

ディスクバルブ３５は、液通路３２を介する作動液のリザーバ室１４から他側室１９への流れを規制しつつ他側室１９からリザーバ室１４への流れを許容する。ディスクバルブ３５は、ピストンロッド２０がシリンダ１１からの延出量を減らす縮み側に移動したときに、他側室１９からリザーバ室１４へ作動液を流し、その際に減衰力を発生させる減衰バルブである。 The disc valve 35 allows the flow of the hydraulic fluid from the other side chamber 19 to the reservoir chamber 14 while restricting the flow of the hydraulic fluid through the liquid passage 32 from the reservoir chamber 14 to the other side chamber 19. The disc valve 35 is a damping valve that causes a damping force to flow from the other side chamber 19 to the reservoir chamber 14 when the piston rod 20 moves to the contraction side that reduces the amount of extension from the cylinder 11. be.

ディスクバルブ３６は、液通路３３を介する作動液の他側室１９からリザーバ室１４への流れを規制しつつリザーバ室１４から他側室１９への流れを許容する。ディスクバルブ３６は、ピストンロッド２０がシリンダ１１からの延出量を増やす伸び側に移動したときに、リザーバ室１４から他側室１９へ作動液を実質的に減衰力を発生させずに流すサクションバルブである。 The disc valve 36 restricts the flow of the hydraulic fluid from the other side chamber 19 to the reservoir chamber 14 through the liquid passage 33 and allows the flow from the reservoir chamber 14 to the other side chamber 19. The disc valve 36 is a suction valve that allows the hydraulic fluid to flow from the reservoir chamber 14 to the other side chamber 19 without substantially generating a damping force when the piston rod 20 moves to the extension side that increases the amount of extension from the cylinder 11. Is.

ピストンロッド２０には、内筒１２内に挿入される側の基端部２１に、上記したピストン１７と、その両側のディスクバルブ４１，４２とが、ナット２３で取り付けられている。ピストン１７には、他側室１９と一側室１８とを連通可能な液通路４３および液通路４４が形成されている。ディスクバルブ４１は、液通路４３を開閉可能であり、ディスクバルブ４２は、液通路４４を開閉可能である。 On the piston rod 20, the above-mentioned piston 17 and disc valves 41 and 42 on both sides thereof are attached to the base end portion 21 on the side to be inserted into the inner cylinder 12 with nuts 23. The piston 17 is formed with a liquid passage 43 and a liquid passage 44 capable of communicating the other side chamber 19 and the one side chamber 18. The disc valve 41 can open and close the liquid passage 43, and the disc valve 42 can open and close the liquid passage 44.

ディスクバルブ４１は、液通路４３を介する作動液の一側室１８から他側室１９への流れを規制しつつ他側室１９から一側室１８への流れを許容する。ディスクバルブ４１は、ピストンロッド２０が縮み側に移動したときに、他側室１９から一側室１８へ作動液を流し、その際に減衰力を発生させる減衰バルブである。 The disc valve 41 allows the flow of the hydraulic fluid from the other side chamber 19 to the one side chamber 18 while restricting the flow of the hydraulic fluid from the one side chamber 18 to the other side chamber 19 through the liquid passage 43. The disc valve 41 is a damping valve that causes a hydraulic fluid to flow from the other side chamber 19 to the one side chamber 18 when the piston rod 20 moves to the contraction side, and generates a damping force at that time.

ディスクバルブ４２は、液通路４４を介する作動液の他側室１９から一側室１８への流れを規制しつつ一側室１８から他側室１９への流れを許容する。ディスクバルブ４２は、ピストンロッド２０が伸び側に移動したときに、一側室１８から他側室１９へ作動液を流し、その際に減衰力を発生させる減衰バルブである。 The disc valve 42 allows the flow of the hydraulic fluid from the one side chamber 18 to the other side chamber 19 while restricting the flow of the hydraulic fluid through the liquid passage 44 from the other side chamber 19 to the one side chamber 18. The disc valve 42 is a damping valve that causes a hydraulic fluid to flow from the one side chamber 18 to the other side chamber 19 when the piston rod 20 moves to the extension side, and generates a damping force at that time.

ピストンロッド２０のシリンダ１１から延出する一側には、カバー部材５１が取り付けられている。カバー部材５１は、ピストンロッド２０のシリンダ１１から延出する一側の軸方向の途中部位に固定される円板状の環状部材５２と、環状部材５２の外周側に接合されて環状部材５２からシリンダ１１の方向に延出する円筒状の筒状部材５３とを有している。筒状部材５３は、シリンダ１１と軸方向に重なっており、シリンダ１１の外周部と、ピストンロッド２０のシール部材２６から突出する部分とを覆っている。 A cover member 51 is attached to one side of the piston rod 20 extending from the cylinder 11. The cover member 51 is joined to the outer peripheral side of the annular member 52 and the disk-shaped annular member 52 fixed to an axially intermediate portion on one side extending from the cylinder 11 of the piston rod 20 from the annular member 52. It has a cylindrical member 53 extending in the direction of the cylinder 11. The tubular member 53 overlaps the cylinder 11 in the axial direction, and covers the outer peripheral portion of the cylinder 11 and the portion of the piston rod 20 protruding from the seal member 26.

外筒１３の底部１５の外側には取付アイ５５が固定されている。 A mounting eye 55 is fixed to the outside of the bottom 15 of the outer cylinder 13.

緩衝器１０は、車両に取り付けられる際に、例えば、ピストンロッド２０が上側に配置されて車体側に連結され、取付アイ５５が下側に配置されて車輪側に連結される。 When the shock absorber 10 is attached to the vehicle, for example, the piston rod 20 is arranged on the upper side and connected to the vehicle body side, and the attachment eye 55 is arranged on the lower side and connected to the wheel side.

緩衝器１０は、ピストンロッド２０が伸び側に移動することで、これと一体にピストン１７が一側室１８の容積を減らし他側室１９の容積を増やす方向に移動すると、ピストン１７に設けられたディスクバルブ４２が、液通路４４を介して一側室１８から他側室１９へ作動液を流し、その際に減衰力を発生させることになる。このとき、ベースバルブ２８のディスクバルブ３６が、リザーバ室１４から他側室１９へ作動液を実質的に減衰力を発生させずに流して、ピストンロッド２０がシリンダ１１から突出した体積分の作動液を他側室１９へ補う。 In the shock absorber 10, when the piston rod 20 moves to the extension side and the piston 17 moves in the direction of reducing the volume of the one side chamber 18 and increasing the volume of the other side chamber 19, the disc provided on the piston 17 is provided. The valve 42 causes the hydraulic fluid to flow from the one side chamber 18 to the other side chamber 19 via the liquid passage 44, and at that time, a damping force is generated. At this time, the disc valve 36 of the base valve 28 causes the hydraulic fluid to flow from the reservoir chamber 14 to the other side chamber 19 without generating a damping force substantially, and the hydraulic fluid corresponding to the volume of the piston rod 20 protruding from the cylinder 11 Is supplemented to the other side chamber 19.

緩衝器１０は、ピストンロッド２０が縮み側に移動することで、これと一体にピストン１７が他側室１９の容積を減らし一側室１８の容積を増やす方向に移動したときに、ピストン１７に設けられたディスクバルブ４１が、液通路４３を介して他側室１９から一側室１８へ作動液を流し、その際に減衰力を発生させることになる。また、このとき、ベースバルブ２８のディスクバルブ３５が、他側室１９からリザーバ室１４へ作動液を流し、その際に減衰力を発生させることになる。 The shock absorber 10 is provided on the piston 17 when the piston rod 20 moves to the contraction side and the piston 17 moves integrally with the piston rod 20 in the direction of reducing the volume of the other side chamber 19 and increasing the volume of the one side chamber 18. The disk valve 41 causes the hydraulic fluid to flow from the other side chamber 19 to the one side chamber 18 via the liquid passage 43, and at that time, a damping force is generated. Further, at this time, the disc valve 35 of the base valve 28 causes the hydraulic fluid to flow from the other side chamber 19 to the reservoir chamber 14, and at that time, a damping force is generated.

ピストン１７は、ピストンロッド２０の基端部２１に連結される金属製のピストン本体６１と、ピストン本体６１の外周部に装着されることでピストン１７の外周部を構成する合成樹脂製のピストンバンド６２とからなっている。ピストン１７は、その外周部を構成するピストンバンド６２が、シリンダ１１の内筒１２の内周部との間をシールする。ピストン１７、これを構成するピストン本体６１およびピストンバンド６２は、ピストンバンド６２においてシリンダ１１の内筒１２に嵌合されると、内筒１２すなわちシリンダ１１と中心軸線を一致させる。 The piston 17 is a metal piston body 61 connected to the base end portion 21 of the piston rod 20, and a synthetic resin piston band that is attached to the outer peripheral portion of the piston main body 61 to form the outer peripheral portion of the piston 17. It consists of 62. The piston band 62, which constitutes the outer peripheral portion of the piston 17, seals between the piston 17 and the inner peripheral portion of the inner cylinder 12 of the cylinder 11. When the piston 17, the piston body 61 and the piston band 62 constituting the piston 17, are fitted into the inner cylinder 12 of the cylinder 11 in the piston band 62, the inner cylinder 12, that is, the cylinder 11 and the central axis are aligned with each other.

ピストン本体６１は、円環状であり、ピストンロッド２０の基端部２１を内周側に嵌合させている。ピストン本体６１には、上記した液通路４３，４４が形成されている。 The piston body 61 has an annular shape, and the base end portion 21 of the piston rod 20 is fitted to the inner peripheral side. The above-mentioned liquid passages 43 and 44 are formed in the piston body 61.

ピストン１７の構成について、さらに説明する。 The configuration of the piston 17 will be further described.

ピストン本体６１は、図２に示すように、本体部６５と、本体部６５から径方向外方に突出する嵌合突出部６６と、を有している。本体部６５および嵌合突出部６６は中心軸線を一致させた円環状をなしている。嵌合突出部６６は、ピストン本体６１の軸方向に間隔をあけて複数並べられている。これにより、軸方向に隣り合う嵌合突出部６６と嵌合突出部６６との間は、これらの外周面よりも径方向内方に凹む円環状の嵌合溝部６７となっている。嵌合溝部６７もピストン本体６１の軸方向に間隔をあけて複数並べられている。複数の嵌合突出部６６は、外径が同等に形成されており、複数の嵌合溝部６７も、溝底径が同等に形成されている。すべての嵌合突出部６６とすべての嵌合溝部６７とが、ピストンバンド６２を装着させる装着部６８を構成している。 As shown in FIG. 2, the piston main body 61 has a main body portion 65 and a fitting protrusion 66 that protrudes outward in the radial direction from the main body portion 65. The main body portion 65 and the fitting protrusion 66 form an annular shape in which the central axes are aligned. A plurality of fitting protrusions 66 are arranged at intervals in the axial direction of the piston body 61. As a result, between the fitting protrusions 66 adjacent to each other in the axial direction and the fitting protrusions 66, there is an annular fitting groove 67 recessed inward in the radial direction from the outer peripheral surfaces thereof. A plurality of fitting groove portions 67 are also arranged at intervals in the axial direction of the piston body 61. The plurality of fitting protrusions 66 are formed to have the same outer diameter, and the plurality of fitting groove portions 67 are also formed to have the same groove bottom diameter. All the fitting protrusions 66 and all the fitting grooves 67 form a mounting portion 68 for mounting the piston band 62.

ピストン本体６１は、装着部６８の一側室１８側の軸方向端部が嵌合突出部６６で構成されており、この軸方向端部の嵌合突出部６６および本体部６５よりも軸方向の一側室１８側に突出する円筒状の軸方向突出部６９が形成されている。軸方向突出部６９は、装着部６８の一側室１８側の軸方向端部の嵌合突出部６６よりも外径が小径となっている。 The piston main body 61 has a fitting protrusion 66 at the axial end on the one side chamber 18 side of the mounting portion 68, and is axially more axial than the fitting protrusion 66 and the main body 65 at the axial end. A cylindrical axially projecting portion 69 projecting toward the one side chamber 18 side is formed. The axially protruding portion 69 has a smaller outer diameter than the fitting protruding portion 66 at the axially end portion on the one side chamber 18 side of the mounting portion 68.

ピストン本体６１は、本体部６５、装着部６８および軸方向突出部６９が一体成形された本体部材７１となっており、本体部材７１の軸方向突出部６９には、本体部材７１とは別体の円環状の金属製の段差形成部材７２（段差部）が嵌合されている。段差形成部材７２は、本体部６５の一側室１８側の軸方向端面に当接している。段差形成部材７２は、外径が、装着部６８の軸方向端部の嵌合突出部６６の外径よりも小径であり、軸方向厚さが軸方向突出部６９の軸方向長さよりも小さくなっている。よって、段差形成部材７２は、装着部６８と軸方向突出部６９との間に設けられて段差状をなす。 The piston main body 61 is a main body member 71 in which the main body portion 65, the mounting portion 68, and the axially protruding portion 69 are integrally molded, and the axially protruding portion 69 of the main body member 71 is a separate body from the main body member 71. An annular metal step forming member 72 (step portion) is fitted. The step forming member 72 is in contact with the axial end surface of the main body 65 on the one side chamber 18 side. The step forming member 72 has an outer diameter smaller than the outer diameter of the fitting protrusion 66 at the axial end of the mounting portion 68, and the axial thickness is smaller than the axial length of the axial protrusion 69. It has become. Therefore, the step forming member 72 is provided between the mounting portion 68 and the axially projecting portion 69 to form a step shape.

ピストンバンド６２は、例えばふっ素樹脂等の低摩擦材、具体的には、ＰＴＦＥ（ポリテトラフルオロエチレン）からなっている。ピストンバンド６２は、円環帯状のバンド本体部８０と、バンド本体部８０から径方向内方に突出する円環状の内周側突出部８１と、を有している。内周側突出部８１は、ピストンバンド６２の軸方向に間隔をあけて複数並べられている。これにより、軸方向に隣り合う内周側突出部８１と内周側突出部８１との間は、これらの外周面よりも径方向外方に凹む円環状の内周側溝部８２となっている。内周側溝部８２はピストンバンド６２の軸方向に間隔をあけて複数並べられている。複数の内周側突出部８１は、内径が同等に形成されており、複数の内周側溝部８２も、溝底径が同等に形成されている。 The piston band 62 is made of, for example, a low friction material such as fluororesin, specifically, PTFE (polytetrafluoroethylene). The piston band 62 has an annular band-shaped band main body 80 and an annular inner peripheral protruding portion 81 protruding inward in the radial direction from the band main body 80. A plurality of inner peripheral side protrusions 81 are arranged at intervals in the axial direction of the piston band 62. As a result, between the inner peripheral side protruding portion 81 and the inner peripheral side protruding portion 81 adjacent to each other in the axial direction, an annular inner peripheral side groove portion 82 that is concave outward in the radial direction from the outer peripheral surface thereof is formed. .. A plurality of inner peripheral side groove portions 82 are arranged at intervals in the axial direction of the piston band 62. The plurality of inner peripheral side protrusions 81 are formed to have the same inner diameter, and the plurality of inner peripheral side groove portions 82 are also formed to have the same groove bottom diameter.

ピストンバンド６２は、ピストン本体６１に装着された状態で、すべての内周側突出部８１が、それぞれ対応する嵌合溝部６７に嵌合して、対応する嵌合溝部６７の溝底部に当接する。また、ピストンバンド６２は、ピストン本体６１に装着された状態で、ピストン本体６１の嵌合突出部６６を、それぞれ対応する内周側溝部８２に嵌合させて、内周側溝部８２の溝底部に当接させる。ピストンバンド６２は、一側室１８側の軸方向端部の嵌合突出部６６に当接する装着当接部８３を有している。ピストンバンド６２は、すべての内周側突出部８１とすべての内周側溝部８２と軸方向の一側室１８側の装着当接部８３とが、ピストン本体６１の装着部６８に嵌合される嵌合部８４を構成している。 In the state where the piston band 62 is attached to the piston body 61, all the inner peripheral side protrusions 81 are fitted into the corresponding fitting groove portions 67 and come into contact with the groove bottom portions of the corresponding fitting groove portions 67. .. Further, in the state where the piston band 62 is attached to the piston main body 61, the fitting protrusion 66 of the piston main body 61 is fitted into the corresponding inner peripheral side groove portion 82, and the groove bottom portion of the inner peripheral side groove portion 82 is fitted. To abut. The piston band 62 has a mounting contact portion 83 that contacts the fitting protrusion 66 at the axial end portion on the one side chamber 18 side. In the piston band 62, all the inner peripheral side protrusions 81, all the inner peripheral side groove portions 82, and the mounting contact portion 83 on the one side chamber 18 side in the axial direction are fitted to the mounting portion 68 of the piston body 61. It constitutes a fitting portion 84.

ピストンバンド６２は、嵌合部８４の一側室１８側の軸方向端部が装着当接部８３で構成されており、嵌合部８４の一側室１８側の軸方向端部の装着当接部８３よりも軸方向に延出する円環状の延出部８５が軸方向の一側室１８側に形成されている。言い換えれば、延出部８５は、ピストン本体６１の装着部６８よりも軸方向の一側室１８側に延出している。 The piston band 62 has a mounting contact portion 83 at the axial end on the one side chamber 18 side of the fitting portion 84, and a mounting contact portion at the axial end on the one side chamber 18 side of the fitting portion 84. An annular extending portion 85 extending in the axial direction from the 83 is formed on the one side chamber 18 side in the axial direction. In other words, the extending portion 85 extends toward the one side chamber 18 side in the axial direction with respect to the mounting portion 68 of the piston main body 61.

延出部８５は、その内周部がピストン本体６１の段差形成部材７２の外径側かつ軸方向の装着部６８とは反対側の端縁部の当接部９５に当接している。ピストンバンド６２は、加熱されることで収縮してピストン本体６１の装着部６８に装着されることになり、その際に、延出部８５は、その角度が段差形成部材７２の当接部９５に当接することで規定される。 The inner peripheral portion of the extending portion 85 is in contact with the abutting portion 95 of the end edge portion on the outer diameter side of the step forming member 72 of the piston body 61 and on the side opposite to the mounting portion 68 in the axial direction. The piston band 62 contracts when heated and is mounted on the mounting portion 68 of the piston body 61. At that time, the extending portion 85 has an angle of the contact portion 95 of the step forming member 72. It is defined by contacting with.

上記した特許文献１には、緩衝装置等に用いられるピストン部として、環状突部を形成したピストンリングをピストン本体に被せた構成のものが記載されている。ピストンリングは、先端側の内周端部がピストン本体に当接している。緩衝器においては、ピストンとシリンダとの間の摩擦特性の調整を容易化する要望がある。 The above-mentioned Patent Document 1 describes, as a piston portion used for a shock absorber or the like, a piston portion having a structure in which a piston ring having an annular protrusion is formed over the piston body. The inner peripheral end of the piston ring on the tip side is in contact with the piston body. In the shock absorber, there is a demand for facilitating the adjustment of the frictional characteristics between the piston and the cylinder.

本実施形態は、ピストン１７のピストンロッド２０に連結されるピストン本体６１が、ピストンバンド６２を装着させる装着部６８と、装着部６８の軸方向端部よりも軸方向に突出する軸方向突出部６９と、装着部６８と軸方向突出部６９との間に設けられて、ピストンバンド６２に当接部９５において当接する段差形成部材７２と、を有するため、段差形成部材７２の外径および軸方向厚さの少なくともいずれか一方を変更することにより、ピストン１７とシリンダ１１の内筒１２との間の摩擦特性の調整を容易化することが可能となる。これにより、所望の仕様毎に緩衝器１０をチューニングすることができる。 In the present embodiment, the piston body 61 connected to the piston rod 20 of the piston 17 has a mounting portion 68 to which the piston band 62 is mounted and an axially protruding portion that protrudes in the axial direction from the axial end portion of the mounting portion 68. Since the piston band 62 is provided between the mounting portion 68 and the mounting portion 68 and the step forming member 72 that abuts on the piston band 62 at the abutting portion 95, the outer diameter and shaft of the step forming member 72 are provided. By changing at least one of the directional thicknesses, it is possible to facilitate the adjustment of the frictional characteristics between the piston 17 and the inner cylinder 12 of the cylinder 11. As a result, the shock absorber 10 can be tuned according to the desired specifications.

例えば、図２に示すように、段差形成部材７２の外径および軸方向厚さを小さくすれば、ピストンバンド６２は、シリンダ１１の内筒１２内に配置される前の組付前状態で、最大外径部９１よりも軸方向の延出部８５側、すなわち先端側の先端側外周部９２と最大外径部９１を通る軸方向線Ｌとのなす角αが、最大外径部９１よりも軸方向の先端側外周部９２とは反対側の基端側外周部９３と最大外径部９１を通る軸方向線Ｌとのなす角βよりも大きくなる。勿論、段差形成部材７２の外径および軸方向厚さの両方を小さくするのではなく、段差形成部材７２の外径および軸方向厚さの少なくともいずれか一方を小さくすれば良い。 For example, as shown in FIG. 2, if the outer diameter and the axial thickness of the step forming member 72 are reduced, the piston band 62 is in the state before assembly before being arranged in the inner cylinder 12 of the cylinder 11. The angle α formed by the extension portion 85 side in the axial direction from the maximum outer diameter portion 91, that is, the tip side outer peripheral portion 92 on the tip side and the axial line L passing through the maximum outer diameter portion 91 is from the maximum outer diameter portion 91. Is larger than the angle β formed by the base end side outer peripheral portion 93 opposite to the axial end side outer peripheral portion 92 and the axial direction line L passing through the maximum outer diameter portion 91. Of course, instead of reducing both the outer diameter and the axial thickness of the step forming member 72, at least one of the outer diameter and the axial thickness of the step forming member 72 may be reduced.

これにより、ピストン１７が内筒１２内に配置されて内筒１２を摺動する際に、ピストンバンド６２には、最大外径部９１の周辺に最大外径部９１を通る先端側外周部９２と基端側外周部９３との二等分線の延長上にモーメントの中心が配置されることになるが、このモーメントの中心を最大外径部９１よりも軸方向の先端側外周部９２とは反対側に配置することができる。 As a result, when the piston 17 is arranged in the inner cylinder 12 and slides on the inner cylinder 12, the piston band 62 has a tip-side outer peripheral portion 92 passing through the maximum outer diameter portion 91 around the maximum outer diameter portion 91. The center of the moment is arranged on the extension of the bisector between the and the base end side outer peripheral portion 93, and the center of this moment is the tip side outer peripheral portion 92 in the axial direction from the maximum outer diameter portion 91. Can be placed on the opposite side.

このように構成すれば、シリンダ１１の内筒１２に対しピストン１７が一側室１８側すなわち伸び方向に移動する際に基端側外周部９３が内筒１２との接触力を高くすることになり、シリンダ１１の内筒１２に対しピストン１７が一側室１８とは反対側すなわち縮み方向に移動する際に基端側外周部９３が内筒１２との接触力を弱めることになる。 With this configuration, when the piston 17 moves toward the one side chamber 18 side, that is, in the extension direction with respect to the inner cylinder 12 of the cylinder 11, the base end side outer peripheral portion 93 increases the contact force with the inner cylinder 12. When the piston 17 moves to the side opposite to the one-side chamber 18, that is, in the contraction direction with respect to the inner cylinder 12 of the cylinder 11, the base end side outer peripheral portion 93 weakens the contact force with the inner cylinder 12.

その結果、図３に実線Ｘ３で示すように、シリンダ１１の内筒１２に対しピストン１７が伸び方向に移動する際に生じるピストン１７とシリンダ１１の内筒１２との間の摩擦力よりも、縮み方向に移動する際に生じるピストン１７とシリンダ１１の内筒１２との間の摩擦力を小さくすることができる。これにより、ロール時に沈み込みやすく、伸び難くなり、車両の姿勢を作りやすくすることができる。 As a result, as shown by the solid line X3 in FIG. 3, the frictional force between the piston 17 and the inner cylinder 12 of the cylinder 11 generated when the piston 17 moves with respect to the inner cylinder 12 of the cylinder 11 is larger than the frictional force generated when the piston 17 moves in the extension direction. The frictional force between the piston 17 and the inner cylinder 12 of the cylinder 11 generated when moving in the contraction direction can be reduced. As a result, it is easy to sink when rolling, it is difficult to stretch, and it is possible to easily make the posture of the vehicle.

また、例えば、図４に示すように、段差形成部材７２の外径および軸方向厚さを図２に示す例よりも大きくすれば、ピストンバンド６２は、シリンダ１１の内筒１２内に配置される前の組付前状態で、最大外径部９１よりも軸方向の延出部８５側、すなわち先端側の先端側外周部９２と最大外径部９１を通る軸方向線Ｌとのなす角αが、最大外径部９１よりも軸方向の先端側外周部９２とは反対側の基端側外周部９３と最大外径部９１を通る軸方向線Ｌとのなす角βと同等になる。勿論、段差形成部材７２の外径および軸方向厚さの両方を大きくするのではなく、段差形成部材７２の外径および軸方向厚さの少なくともいずれか一方を大きくすれば良い。 Further, for example, as shown in FIG. 4, if the outer diameter and the axial thickness of the step forming member 72 are made larger than those shown in FIG. 2, the piston band 62 is arranged in the inner cylinder 12 of the cylinder 11. In the pre-assembly state before assembly, the angle formed by the extension portion 85 side in the axial direction from the maximum outer diameter portion 91, that is, the tip side outer peripheral portion 92 on the tip side and the axial line L passing through the maximum outer diameter portion 91. α becomes equivalent to the angle β formed by the base end side outer peripheral portion 93 opposite to the distal end side outer peripheral portion 92 in the axial direction of the maximum outer diameter portion 91 and the axial line L passing through the maximum outer diameter portion 91. .. Of course, instead of increasing both the outer diameter and the axial thickness of the step forming member 72, at least one of the outer diameter and the axial thickness of the step forming member 72 may be increased.

これにより、ピストン１７が内筒１２内に配置されて内筒１２を摺動する際に、ピストンバンド６２には、最大外径部９１の周辺に最大外径部９１を通る先端側外周部９２と基端側外周部９３との二等分線の延長上にモーメントの中心が配置されることになるが、このモーメントの中心を最大外径部９１と軸方向の位置を合わせることができる。 As a result, when the piston 17 is arranged in the inner cylinder 12 and slides on the inner cylinder 12, the piston band 62 has a tip-side outer peripheral portion 92 passing through the maximum outer diameter portion 91 around the maximum outer diameter portion 91. The center of the moment is arranged on the extension of the bisector between the and the outer peripheral portion 93 on the base end side, and the center of this moment can be aligned with the maximum outer diameter portion 91 in the axial direction.

このように構成すれば、シリンダ１１の内筒１２に対しピストン１７が一側室１８側すなわち伸び方向に移動する際の基端側外周部９３の内筒１２との密着力と、シリンダ１１の内筒１２に対しピストン１７が一側室１８とは反対側すなわち縮み方向に移動する際の基端側外周部９３の内筒１２との密着力とを同等にすることができる。また、シリンダ１１の内筒１２に対しピストン１７が一側室１８側すなわち伸び方向に移動する際の先端側外周部９２の内筒１２との密着力と、シリンダ１１の内筒１２に対しピストン１７が一側室１８とは反対側すなわち縮み方向に移動する際の先端側外周部９２の内筒１２との密着力とを同等にすることができる。 With this configuration, the contact force of the piston 17 with respect to the inner cylinder 12 of the cylinder 11 with the inner cylinder 12 of the base end side outer peripheral portion 93 when the piston 17 moves toward the one side chamber 18, that is, in the extension direction, and the inside of the cylinder 11. It is possible to make the adhesion force of the outer peripheral portion 93 on the base end side with the inner cylinder 12 when the piston 17 moves to the side opposite to the one side chamber 18 with respect to the cylinder 12 in the contraction direction. Further, the contact force of the piston 17 with respect to the inner cylinder 12 of the cylinder 11 with respect to the inner cylinder 12 of the outer peripheral portion 92 on the tip side when the piston 17 moves toward the one side chamber 18, that is, in the extension direction, and the piston 17 with respect to the inner cylinder 12 of the cylinder 11. The contact force of the outer peripheral portion 92 on the tip end side with the inner cylinder 12 when moving to the opposite side of the one-side chamber 18, that is, in the contraction direction can be made equal.

その結果、図３に破線Ｘ２で示すように、シリンダ１１の内筒１２に対しピストン１７が伸び方向に移動する際に生じるピストン１７とシリンダ１１の内筒１２との間の摩擦力を、縮み方向に移動する際に生じるピストン１７とシリンダ１１の内筒１２との間の摩擦力と同等にすることができる。 As a result, as shown by the broken line X2 in FIG. 3, the frictional force between the piston 17 and the inner cylinder 12 of the cylinder 11 generated when the piston 17 moves with respect to the inner cylinder 12 of the cylinder 11 is reduced. It can be made equal to the frictional force between the piston 17 and the inner cylinder 12 of the cylinder 11 generated when moving in the direction.

また、例えば、図５に示すように、段差形成部材７２の外径および軸方向厚さを図４に示す例よりもさらに大きくすれば、ピストンバンド６２は、シリンダ１１の内筒１２内に配置される前の組付前状態で、最大外径部９１よりも軸方向の延出部８５側、すなわち先端側の先端側外周部９２と最大外径部９１を通る軸方向線Ｌとのなす角αが、最大外径部９１よりも軸方向の先端側外周部９２とは反対側の基端側外周部９３と最大外径部９１を通る軸方向線Ｌとのなす角βよりも小さくなる。勿論、段差形成部材７２の外径および軸方向厚さの両方をさらに大きくするのではなく、段差形成部材７２の外径および軸方向厚さの少なくともいずれか一方をさらに大きくすれば良い。 Further, for example, as shown in FIG. 5, if the outer diameter and the axial thickness of the step forming member 72 are further increased than in the example shown in FIG. 4, the piston band 62 is arranged in the inner cylinder 12 of the cylinder 11. In the state before assembly before assembly, the extension portion 85 side in the axial direction from the maximum outer diameter portion 91, that is, the tip side outer peripheral portion 92 on the tip side and the axial line L passing through the maximum outer diameter portion 91 are formed. The angle α is smaller than the angle β formed by the base end side outer peripheral portion 93 opposite to the distal end side outer peripheral portion 92 in the axial direction and the axial line L passing through the maximum outer diameter portion 91 than the maximum outer diameter portion 91. Become. Of course, instead of further increasing both the outer diameter and the axial thickness of the step forming member 72, at least one of the outer diameter and the axial thickness of the step forming member 72 may be further increased.

これにより、ピストン１７が内筒１２内に配置されて内筒１２を摺動する際に、ピストンバンド６２には、最大外径部９１の周辺に最大外径部９１を通る先端側外周部９２と基端側外周部９３との二等分線の延長上にモーメントの中心が配置されるが、このモーメントの中心を最大外径部９１よりも軸方向の先端側外周部９２側に配置することができる。 As a result, when the piston 17 is arranged in the inner cylinder 12 and slides on the inner cylinder 12, the piston band 62 has a tip-side outer peripheral portion 92 passing through the maximum outer diameter portion 91 around the maximum outer diameter portion 91. The center of the moment is arranged on the extension of the bisector between the and the base end side outer peripheral portion 93, and the center of this moment is arranged on the tip side outer peripheral portion 92 side in the axial direction from the maximum outer diameter portion 91. be able to.

このように構成すれば、シリンダ１１の内筒１２に対しピストン１７が一側室１８側すなわち伸び方向に移動する際に先端側外周部９２が内筒１２との接触力を低くすることになり、シリンダ１１の内筒１２に対しピストン１７が一側室１８とは反対側すなわち縮み方向に移動する際に先端側外周部９２が内筒１２との接触力を高くすることになる。 With this configuration, when the piston 17 moves toward the one side chamber 18 side, that is, in the extension direction with respect to the inner cylinder 12 of the cylinder 11, the outer peripheral portion 92 on the tip side lowers the contact force with the inner cylinder 12. When the piston 17 moves with respect to the inner cylinder 12 of the cylinder 11 on the side opposite to the one-side chamber 18, that is, in the contraction direction, the outer peripheral portion 92 on the tip end side increases the contact force with the inner cylinder 12.

これにより、図３に二点鎖線Ｘ１で示すように、シリンダ１１の内筒１２に対しピストン１７が伸び方向に移動する際に生じるピストン１７とシリンダ１１の内筒１２との間の摩擦力よりも、縮み方向に移動する際に生じるピストン１７とシリンダ１１の内筒１２との間の摩擦力を大きくすることができる。これにより、縮み行程で緩衝器１０のはり感が生じ、車両の乗り心地を改善することができる。 As a result, as shown by the two-point chain line X1 in FIG. 3, the frictional force between the piston 17 and the inner cylinder 12 of the cylinder 11 generated when the piston 17 moves with respect to the inner cylinder 12 of the cylinder 11 Also, the frictional force between the piston 17 and the inner cylinder 12 of the cylinder 11 generated when moving in the contraction direction can be increased. As a result, a feeling of elasticity of the shock absorber 10 is generated in the contraction stroke, and the riding comfort of the vehicle can be improved.

段差形成部材７２は、装着部６８および軸方向突出部６９を含む本体部材７１とは別体であるため、段差形成部材７２の変更が一層容易となり、ピストン１７とシリンダ１１の内筒１２との間の摩擦特性を一層容易に調整することが可能となる。また、本体部材７１は共通とし、段差形成部材７２のみを異ならせれば良いため、コスト増を抑制することができる。 Since the step forming member 72 is separate from the main body member 71 including the mounting portion 68 and the axially projecting portion 69, it is easier to change the step forming member 72, and the piston 17 and the inner cylinder 12 of the cylinder 11 are combined. The frictional characteristics between them can be adjusted more easily. Further, since the main body member 71 is common and only the step forming member 72 needs to be different, the cost increase can be suppressed.

ここで、ピストンバンド６２の延出部８５に当接して、延出部８５の先端側外周部９２および基端側外周部９３の角度を規定する段差形成部材７２の当接部９５を、図６に示すように、装着部６８から軸方向に離れるほど小径となるテーパ状にしても良い。これにより、ピストンバンド６２のピストン本体６１への熱収縮による装着時に、延出部８５の先端側外周部９２および基端側外周部９３の角度をより安定的に規定することができる。 Here, FIG. As shown in 6, the taper shape may be formed so that the diameter becomes smaller as the distance from the mounting portion 68 in the axial direction increases. Thereby, when the piston band 62 is attached to the piston body 61 by heat shrinkage, the angles of the outer peripheral portion 92 on the distal end side and the outer peripheral portion 93 on the proximal end side of the extending portion 85 can be more stably defined.

以上の実施形態においては、ピストン本体６１の一側室１８側に、装着部６８の一側室１８側の軸方向端部よりも軸方向の一側室１８側に突出する軸方向突出部６９と、ピストンバンド６２に当接する段差形成部材７２とを設ける場合を例にとり説明したが、ピストン本体６１の他側室１９側に、装着部６８の他側室１９側の軸方向端部よりも軸方向の他側室１９側に突出する軸方向突出部６９と、ピストンバンド６２に当接する段差形成部材７２とを設けても良い。すなわち、ピストン本体６１の軸方向の両端側のうち、少なくともいずれか一側に、装着部６８の軸方向端部よりも軸方向に突出する軸方向突出部６９と、ピストンバンド６２に当接する段差形成部材７２とを設ければ良い。 In the above embodiment, the piston body 61 has an axially protruding portion 69 protruding toward the one side chamber 18 side in the axial direction from the axial end portion on the one side chamber 18 side of the mounting portion 68, and the piston. Although the case where the step forming member 72 that abuts the band 62 is provided has been described as an example, the other side chamber in the axial direction is located on the other side chamber 19 side of the piston body 61 and is more axial than the axial end portion on the other side chamber 19 side of the mounting portion 68. An axially projecting portion 69 projecting to the 19 side and a step forming member 72 abutting on the piston band 62 may be provided. That is, on at least one of both ends of the piston body 61 in the axial direction, an axially protruding portion 69 that protrudes in the axial direction from the axially end portion of the mounting portion 68 and a step that abuts on the piston band 62. The forming member 72 may be provided.

以上の実施形態においては、段差形成部材７２が、装着部６８および軸方向突出部６９を含む本体部材７１とは別体としたが、装着部６８および軸方向突出部６９を含む本体部材７１に一体の段差部として形成しても良い。 In the above embodiment, the step forming member 72 is separated from the main body member 71 including the mounting portion 68 and the axially protruding portion 69, but the main body member 71 including the mounting portion 68 and the axially protruding portion 69 It may be formed as an integral step portion.

以上に述べた実施形態の第１の態様は、作動流体が封入されるシリンダと、前記シリンダ内に摺動可能に嵌装されて該シリンダ内を一側室と他側室とに画成するピストンと、前記ピストンに連結されて前記シリンダの外部へ延出されるピストンロッドと、を備える緩衝器であって、前記ピストンは、前記ピストンロッドに連結されるピストン本体と、前記ピストン本体の外周部に装着されて前記シリンダの内周部との間をシールするピストンバンドと、を有し、前記ピストンバンドは、前記シリンダ内に配置される前の組付前状態で、最大外径部よりも先端側の先端側外周部と前記最大外径部を通る軸方向線とのなす角が、前記最大外径部よりも前記先端側外周部とは反対側の基端側外周部と前記最大外径部を通る軸方向線とのなす角よりも大きいことを特徴とする。 The first aspect of the embodiment described above is a cylinder in which a working fluid is sealed, and a piston that is slidably fitted in the cylinder and defines the inside of the cylinder into a one-side chamber and another side chamber. , A shock absorber including a piston rod connected to the piston and extended to the outside of the cylinder, the piston is mounted on the piston body connected to the piston rod and the outer peripheral portion of the piston body. It has a piston band that seals between the inner peripheral portion of the cylinder, and the piston band is on the tip side of the maximum outer diameter portion in the state before assembly before being arranged in the cylinder. The angle between the outer peripheral portion on the tip end side and the axial line passing through the maximum outer diameter portion is the outer peripheral portion on the proximal end side and the maximum outer diameter portion on the side opposite to the outer peripheral portion on the tip end side with respect to the outer peripheral portion on the tip end side. It is characterized in that it is larger than the angle formed by the axial line passing through.

第２の態様は、作動流体が封入されるシリンダと、前記シリンダ内に摺動可能に嵌装されて該シリンダ内を一側室と他側室とに画成するピストンと、前記ピストンに連結されて前記シリンダの外部へ延出されるピストンロッドと、を備える緩衝器であって、前記ピストンは、前記ピストンロッドに連結されるピストン本体と、前記ピストン本体の外周部に装着されて前記シリンダの内周部との間をシールするピストンバンドと、を有し、前記ピストンバンドは、前記シリンダ内に配置される前の組付前状態で、最大外径部よりも先端側の先端側外周部と前記最大外径部を通る軸方向線とのなす角が、前記最大外径部よりも前記先端側外周部とは反対側の基端側外周部と前記最大外径部を通る軸方向線とのなす角よりも小さいことを特徴とする。 The second aspect is connected to the piston, a cylinder in which the working fluid is sealed, a piston that is slidably fitted in the cylinder and defines the inside of the cylinder into one side chamber and the other side chamber. A shock absorber comprising a piston rod extending to the outside of the cylinder, wherein the piston is attached to a piston body connected to the piston rod and an outer peripheral portion of the piston body and is attached to the inner circumference of the cylinder. It has a piston band that seals between the portions, and the piston band is in a state before assembly before being arranged in the cylinder, and the outer peripheral portion on the tip side on the tip side of the maximum outer diameter portion and the outer peripheral portion on the tip side. The angle formed by the axial line passing through the maximum outer diameter portion is the distance between the outer peripheral portion on the proximal end side opposite to the outer peripheral portion on the tip side of the maximum outer diameter portion and the axial direction line passing through the maximum outer diameter portion. It is characterized by being smaller than the piston.

第３の態様は、第１，第２のいずれか一態様において、前記ピストン本体は、前記ピストンバンドを装着させる装着部と、前記装着部の軸方向端部よりも軸方向に突出する軸方向突出部と、前記装着部と前記軸方向突出部との間に設けられて、前記ピストンバンドに当接する段差部と、を有することを特徴とする。 In the third aspect, in any one of the first and second aspects, the piston body has a mounting portion on which the piston band is mounted and an axial direction protruding from the axial end portion of the mounting portion. It is characterized by having a protruding portion and a stepped portion provided between the mounting portion and the axially protruding portion and in contact with the piston band.

第４の態様は、第３の態様において、前記段差部は、前記ピストンバンドに当接する当接部がテーパ状であることを特徴とする。 A fourth aspect is characterized in that, in the third aspect, the stepped portion has a tapered contact portion that abuts on the piston band.

第５の態様は、第３，第４のいずれか一態様において、前記段差部は、前記装着部および前記軸方向突出部とは別体であることを特徴とする。 A fifth aspect is characterized in that, in any one of the third and fourth aspects, the stepped portion is separate from the mounting portion and the axially projecting portion.

１０緩衝器
１１シリンダ
１７ピストン
１８一側室
１９他側室
２０ピストンロッド
６１ピストン本体
６２ピストンバンド
６８装着部
６９軸方向突出部
７２段差形成部材（段差部）
９１最大外径部
９２先端側外周部
９３基端側外周部
９５当接部 10 Shock absorber 11 Cylinder 17 Piston 18 One side chamber 19 Other side chamber 20 Piston rod 61 Piston body 62 Piston band 68 Mounting part 69 Axial protrusion 72 Step forming member (step part)
91 Maximum outer diameter part 92 Tip side outer circumference 93 Base end side outer circumference 95 Contact part

Claims

Cylinder in which working fluid is sealed and
A piston that is slidably fitted in the cylinder and defines the inside of the cylinder as a concubine and a concubine.
A piston rod that is connected to the piston and extends to the outside of the cylinder,
It is a shock absorber equipped with
The piston
The piston body connected to the piston rod and
It has a piston band that is attached to the outer peripheral portion of the piston body and seals between the inner peripheral portion of the cylinder.
The piston body
A mounting portion for mounting the piston band and
Axial protrusions that project axially from the axial ends of the mounting portion, and
It has a stepped portion provided between the mounting portion and the axially protruding portion and in contact with the piston band.
In the pre-assembled state before the piston band is placed in the cylinder, the angle formed by the tip-side outer peripheral portion on the tip end side of the maximum outer diameter portion and the axial line passing through the maximum outer diameter portion is A shock absorber characterized in that it is larger than the angle formed by the base end side outer peripheral portion on the side opposite to the tip end side outer peripheral portion and the axial line passing through the maximum outer diameter portion.

Cylinder in which working fluid is sealed and
A piston that is slidably fitted in the cylinder and defines the inside of the cylinder as a concubine and a concubine.
A piston rod that is connected to the piston and extends to the outside of the cylinder,
It is a shock absorber equipped with
The piston
The piston body connected to the piston rod and
It has a piston band that is attached to the outer peripheral portion of the piston body and seals between the inner peripheral portion of the cylinder.
The piston body
A mounting portion for mounting the piston band and
Axial protrusions that project axially from the axial ends of the mounting portion, and
It has a stepped portion provided between the mounting portion and the axially protruding portion and in contact with the piston band.
In the pre-assembled state before the piston band is placed in the cylinder, the angle formed by the tip-side outer peripheral portion on the tip end side of the maximum outer diameter portion and the axial line passing through the maximum outer diameter portion is A shock absorber characterized in that it is smaller than the angle formed by the base end side outer peripheral portion on the side opposite to the tip end side outer peripheral portion and the axial line passing through the maximum outer diameter portion.

The shock absorber according to claim 1 or 2 , wherein the stepped portion has a tapered contact portion that abuts on the piston band.

The shock absorber according to any one of claims 1 to 3 , wherein the stepped portion is separate from the mounting portion and the axially projecting portion.