JPH0379831A - Hydraulic shock absorber - Google Patents
Hydraulic shock absorberInfo
- Publication number
- JPH0379831A JPH0379831A JP21660489A JP21660489A JPH0379831A JP H0379831 A JPH0379831 A JP H0379831A JP 21660489 A JP21660489 A JP 21660489A JP 21660489 A JP21660489 A JP 21660489A JP H0379831 A JPH0379831 A JP H0379831A
- Authority
- JP
- Japan
- Prior art keywords
- spool
- chamber
- pressure
- piston
- pressure chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 239000006096 absorbing agent Substances 0.000 title claims abstract description 22
- 230000035939 shock Effects 0.000 title claims abstract description 22
- 238000013016 damping Methods 0.000 abstract description 33
- 230000005284 excitation Effects 0.000 abstract description 15
- 230000007423 decrease Effects 0.000 abstract description 8
- 230000007935 neutral effect Effects 0.000 abstract description 3
- 230000003111 delayed effect Effects 0.000 abstract 1
- 239000003921 oil Substances 0.000 description 54
- 239000010720 hydraulic oil Substances 0.000 description 14
- 230000007246 mechanism Effects 0.000 description 13
- 238000005192 partition Methods 0.000 description 7
- 230000006835 compression Effects 0.000 description 6
- 238000007906 compression Methods 0.000 description 6
- 230000001419 dependent effect Effects 0.000 description 5
- 239000000725 suspension Substances 0.000 description 5
- 238000006073 displacement reaction Methods 0.000 description 4
- 230000008859 change Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000011038 discontinuous diafiltration by volume reduction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 239000002649 leather substitute Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000004043 responsiveness Effects 0.000 description 1
Landscapes
- Vehicle Body Suspensions (AREA)
- Fluid-Damping Devices (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、車輌用サスペンション機構への利用に最適
な周波数依存型の油圧緩衝器に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a frequency-dependent hydraulic shock absorber that is most suitable for use in a vehicle suspension mechanism.
周知のように、車輌の車軸懸架における振動形態は、２
自由度の振動系であり、それ故、走行中の路面からの振
動入力によって、該振動系における將定の振動周波数領
域で共振動作が起きる。As is well known, there are two types of vibration in the axle suspension of a vehicle.
It is a vibration system with many degrees of freedom, and therefore, resonance operation occurs in a fixed vibration frequency range in the vibration system due to vibration input from the road surface while driving.
そして、該共振動作のピーク時たる共振点には、比較的
低周波数領域での一次共振点と比較的高周波数領域での
二次共振点とがある。The resonance points at the peak of the resonance operation include a primary resonance point in a relatively low frequency region and a secondary resonance point in a relatively high frequency region.
ところで、上記共振動作を制御したいと、−次共振点付
近では、ばね上の振動が大きくなつて走行中の車輌の乗
心地が損なわれ、二次共振点付近では、ばね下の振動が
大きくたって車輪の接地性及び操縦安定性が悪化される
。By the way, if we want to control the above-mentioned resonance operation, the vibrations on the springs become large near the -order resonance point, which impairs the riding comfort of the running vehicle, and the vibrations on the springs become large near the secondary resonance points. The ground contact and steering stability of the wheels are deteriorated.
以上の状況を防ぐには、サスペンション機構における減
衰力を上記各共振点付近の周波数域で変化させるように
した加振周波数応答型の減衰力調整式の油圧緩衝器の採
用が望まれる。In order to prevent the above situation, it is desirable to employ an excitation frequency responsive type damping force adjustable hydraulic shock absorber that changes the damping force in the suspension mechanism in the frequency range near each resonance point.
しかして、かかる減衰力調整式油圧緩衝器の数種がすで
に提案されている。Several types of such damping force adjustable hydraulic shock absorbers have already been proposed.
ところで、従来提案の減衰力調整式油圧緩衝器の内、減
衰バルブの減衰係数を加振周波数に応じて切換変更する
。ものにあっては、周波数検出機構やアクチュエータ機
構等の附加で緩衝器自体の構造が複雑となり、組立工程
数の増大や生産性の低下等によるコスト高を招来する不
都合がある。By the way, among the conventionally proposed damping force adjustable hydraulic shock absorbers, the damping coefficient of the damping valve is switched and changed according to the excitation frequency. However, the addition of a frequency detection mechanism, an actuator mechanism, etc. complicates the structure of the shock absorber itself, resulting in an increase in costs due to an increase in the number of assembly steps and a decrease in productivity.
また、環状リーフバルブからたる減衰バルブの撓み剛性
を変更して発生減衰力を変更するものにあっては、単一
の環状リーフバルブに異なる大きさの撓みが繰り返され
ることから、その金属疲労ｆｘどによるバルブ折損事故
が起き易くなり、機能安定性に欠ける不都合がある。In addition, in the case where the generated damping force is changed by changing the deflection rigidity of the damping valve barreling from the annular leaf valve, the metal fatigue f This has the disadvantage that valve breakage accidents are more likely to occur due to etc., and functional stability is lacking.
そこで、この発明は、機構上並びに機能上において従来
手段の不都合たところを一挙に解決し得るようにした周
波数依存型の減衰力調整式油圧緩衝器を提供することを
目的とするものである。SUMMARY OF THE INVENTION An object of the present invention is to provide a frequency-dependent damping force adjustable hydraulic shock absorber that can solve the mechanical and functional disadvantages of conventional means at once.
上記の目的を達成するために、本発明の構成はシリンダ
内にピストンを介してピストンロッドが移動自在に挿入
され、ピストンはシリンダ内に上下二つの油室を区画し
、二つの油室はピストンに設けた伸ポートと圧ポートと
各ボートの出口端にそれぞれ設けた伸リーフバルブと圧
リーフバルブを介して開閉される油圧緩衝器に於て、ピ
ストンロッド内の上方にリザーバを設け、同じくピスト
ンロッド内の下方に圧力室を設け、リザーバと圧力室と
の間に一方向に付勢されたスプールを上下移動自在に挿
入すると共に当該スプールにはリザーバと圧力室を通じ
させるボートを形成し、スプール内の圧力室側ポート出
口にはチェックバルブが開閉自在に設けられ、前記圧力
室内には一方向に付勢されたプランジャが上下移動自在
に設けられ、プランジャの背部側は通孔を介して下部油
室に開口し、更にピストンとピストンロッドには上下二
つの油室を連通ずるバイパスを設け、当該バイパスは前
記スプールの上下動に伴たって開閉されることを特徴と
するものである。In order to achieve the above object, the structure of the present invention is such that a piston rod is movably inserted into a cylinder via a piston, the piston divides the cylinder into two upper and lower oil chambers, and the two oil chambers are connected to the piston. In the hydraulic shock absorber, which is opened and closed via the extension port and pressure port provided at the piston rod, and the extension leaf valve and pressure leaf valve provided at the outlet end of each boat, a reservoir is provided above the piston rod, and a reservoir is provided above the piston rod. A pressure chamber is provided in the lower part of the rod, and a spool biased in one direction is inserted between the reservoir and the pressure chamber so as to be movable up and down, and a boat is formed in the spool to allow communication between the reservoir and the pressure chamber. A check valve is provided at the pressure chamber side port outlet in the pressure chamber so that it can be opened and closed, and a plunger biased in one direction is provided in the pressure chamber so as to be movable up and down. The piston and the piston rod are provided with a bypass which opens into the oil chamber and communicates the two upper and lower oil chambers, and the bypass is opened and closed as the spool moves up and down.
外部加振によって上下動するピストン及びそのピストン
ロッドの動作に連れて、該ピストンで区分される上下油
室の作動油がピストンに設けた減衰バルブ機構を通って
移動する間に減衰力が発生する一方、ピストンロッドの
出入によるシリンダ内容室の増減相当分の作動油を外筒
との間の油室から補充又は戻すように作用する。As the piston and its piston rod move up and down due to external vibration, a damping force is generated while the hydraulic oil in the upper and lower oil chambers divided by the piston moves through a damping valve mechanism provided on the piston. On the other hand, it acts to replenish or return hydraulic oil corresponding to the increase or decrease in the cylinder inner chamber from the oil chamber between the outer cylinder and the inner cylinder due to the movement of the piston rod in and out.
そして、加振周波数に応答する圧力室内のプランジャは
、ピストンで区分される下部油室の室圧を受けて動作す
る。The plunger in the pressure chamber, which responds to the excitation frequency, operates in response to chamber pressure in the lower oil chamber divided by the piston.
上記プランジャの上下動作で内圧が変化する圧力室には
、その室圧の低下で開弁するチェックバルブを介してリ
ザーバー室からの作動油が流入すると共に若干遅れてス
プールが下降し、内圧上昇初期で該チェックバルブによ
るリザーバー室への連通ポートが絞られるので、スプー
ルが圧力室の内圧で上昇する。The hydraulic oil from the reservoir chamber flows into the pressure chamber, where the internal pressure changes with the vertical movement of the plunger, through a check valve that opens when the chamber pressure decreases, and the spool descends with a slight delay, causing the internal pressure to begin to rise. Since the communication port to the reservoir chamber is throttled by the check valve, the spool rises due to the internal pressure of the pressure chamber.
そして、スプールの中立、上下動に伴なってバイパスが
開閉され、バイパスの開閉による高減衰力と低減衰力が
発生する。The bypass is opened and closed as the spool moves up and down, and high damping force and low damping force are generated by opening and closing the bypass.
以下、図示した実施例に基いて、この発明の詳細な説明
する。Hereinafter, the present invention will be described in detail based on the illustrated embodiments.
矛１図に示すように、この発明の一実施例に係る油圧緩
衝器は、シリンダ１内にピストンロッド２に支持された
ピストン３を摺動自在に収装する一方で、シリンダ１外
周の外筒４の上下動をキャップによって閉塞した構成と
し、即ち、シリンダ体を上記シリンダ１と外筒４とで形
成した複筒ガス式のショックアブソーバとなしである。As shown in Figure 1, the hydraulic shock absorber according to one embodiment of the present invention has a piston 3 supported by a piston rod 2 slidably housed in a cylinder 1, and a The configuration is such that the vertical movement of the cylinder 4 is blocked by a cap, that is, a double cylinder gas type shock absorber in which the cylinder body is formed by the cylinder 1 and the outer cylinder 4 is used.
そして、上記シリンダ１内はピストン３によって作動油
の充填された上部油室６と下部油室７とに区分され、こ
れら両室６及び７間を該ピストン３に配置した減衰バル
ブ機構によって連通しである。The inside of the cylinder 1 is divided by a piston 3 into an upper oil chamber 6 filled with hydraulic oil and a lower oil chamber 7, and these two chambers 6 and 7 are communicated by a damping valve mechanism disposed in the piston 3. It is.
一方、前記ピストンロッド２は中空軸体で構成され、そ
の外端施栓下に密封された中空部に油室９と空気室とが
形成さ力ている。On the other hand, the piston rod 2 is constituted by a hollow shaft body, and an oil chamber 9 and an air chamber are formed in a sealed hollow portion below the outer end of the piston rod 2 .
そして、該油室９は前記減衰バルブ機構における絞り開
度を制御するための作動油回路におけるリザーバー室と
して機能し、後述する作動時の該油室９におけるわずか
な体積変化を前記空気室の圧縮膨張により吸収して、上
記リザーバー室の内圧を常に略一定に保持するようにた
しである。The oil chamber 9 functions as a reservoir chamber in a hydraulic oil circuit for controlling the throttle opening degree in the damping valve mechanism, and a slight change in volume in the oil chamber 9 during operation, which will be described later, is compensated for by compression of the air chamber. This is done so that the internal pressure of the reservoir chamber is always kept substantially constant by absorbing it through expansion.
尚、この作動油回路は、その流路系が前記上部油室６及
び下部油室７に対して独立した閉回路として構成されて
いる。Note that this hydraulic oil circuit is constructed as a closed circuit whose flow path system is independent of the upper oil chamber 6 and the lower oil chamber 7.
他方、外筒４とシリンダ１との間には、油室１１とガス
室とが形成され、前記下部油室７との間に圧側減衰力発
生用のベースバルブ機構を介在させて連通した上記油室
１１の作動油で、ピストン３のストローク動作時におけ
るピストンロッド２のシリンダ１内への出没によるシリ
ンダ内容積変化分を補うと共に、上記ガス室並びに先の
空気室の高圧下での圧縮膨張によって作動時にねける各
流路でのキャビテーションの発生を防ぐようにな−しで
ある。On the other hand, an oil chamber 11 and a gas chamber are formed between the outer cylinder 4 and the cylinder 1, and communicate with the lower oil chamber 7 through a base valve mechanism for generating compression side damping force. The hydraulic oil in the oil chamber 11 compensates for the change in cylinder internal volume due to the piston rod 2 moving in and out of the cylinder 1 during the stroke operation of the piston 3, and also compresses and expands the gas chamber and the previous air chamber under high pressure. This prevents cavitation from occurring in each flow path during operation.
次に、前記減衰バルブ機構について少しく説明するが、
その際、上述の図示構成と共通する各部分については、
同一の記号を符す。Next, the damping valve mechanism will be explained in detail.
At that time, regarding each part common to the above-mentioned illustrated configuration,
marked with the same symbol.
即ち、第２図に示すように、該減衰バルブ機構を構成す
る前記ピストン３は筒状体からなると共に、これをピス
トンロッド２の先端に嵌装し、基部カラーと先端のピス
トンナツト１９との間で挾持しである。That is, as shown in FIG. 2, the piston 3 constituting the damping valve mechanism is made of a cylindrical body, and is fitted onto the tip of the piston rod 2, so that the base collar and the piston nut 19 at the tip are connected. It is caught in between.
ピストン３には上下二つの油室６，７を連通する伸側ポ
ート３１と圧側ボート３２が縦方向に形成され、伸側ポ
ート３１の下部出口シートには伸側リーフバルブ３３が
開閉自在に設けられ、圧側ポート３２の上部出口シート
には圧側リーフバルブ３４が開閉自在に設けられ、伸長
時上部油室６の油が伸側ポート３１より伸側リーフバル
ブ３３を押し開いて伸側減衰力を発生させ、圧縮時には
下部油室７の油が圧側ボート３２より圧側リーフバルブ
３４を押し開いて上部油室６に流出して圧側減衰力を発
生させる。A growth side port 31 and a pressure side boat 32 are formed in the vertical direction on the piston 3 to communicate the two upper and lower oil chambers 6 and 7, and a growth side leaf valve 33 is provided in the lower outlet seat of the growth side port 31 so as to be openable and closable. A compression side leaf valve 34 is provided on the upper outlet seat of the compression side port 32 so as to be openable and closable, and during expansion, the oil in the upper oil chamber 6 pushes open the expansion side leaf valve 33 from the expansion side port 31 to exert a rebound damping force. During compression, the oil in the lower oil chamber 7 pushes open the pressure side leaf valve 34 from the pressure side boat 32 and flows into the upper oil chamber 6 to generate a compression side damping force.
ピストン３とピストンロッド２には半径方向に向けてバ
イパスＡたる通路３６，３７．３８と上下二つの通孔３
９α、３９ｈとが形成され、このバイパスＡは後述する
ピストンロッド２内のスプール２０で開閉され、バイパ
スＡの開閉に伴たってリーフバルブ３３．３４と協働す
る合皮の高減衰力又は低減衰力が発生するようになって
いる。The piston 3 and the piston rod 2 have passages 36, 37, 38 which are bypass A and two upper and lower through holes 3 in the radial direction.
9α, 39h are formed, and this bypass A is opened and closed by a spool 20 in the piston rod 2, which will be described later, and as the bypass A is opened and closed, high damping force or low damping force of the synthetic leather cooperates with leaf valves 33 and 34. Force is generated.
ピストンロッド２内には隔壁部材４０ 、４１． 。Inside the piston rod 2 are partition members 40, 41. .
４２が設けられ、隔壁部材４０より上方にリザーバ側の
油室９が区画され、隔壁部材４０．４］との間に油室４
３が区画され、隔壁部材４１゜４２の間に圧力室２９が
区画され、油室９，４３は隔壁部材４０の通孔αを介し
て連通し、油室４３と圧力室２９は隔壁部材４１の通孔
りを介して連通し、圧力室２９は隔壁部材４２の通孔ｃ
ｆ介して下部油室７に連通している。42 is provided, an oil chamber 9 on the reservoir side is defined above the partition member 40, and an oil chamber 4 is provided between the partition wall member 40.4].
3 is partitioned, and a pressure chamber 29 is partitioned between the partition members 41 and 42. The oil chambers 9 and 43 communicate through the through hole α of the partition member 40, and the oil chamber 43 and the pressure chamber 29 are The pressure chamber 29 communicates with the through hole c of the partition member 42.
It communicates with the lower oil chamber 7 via f.
油室４３内にはスプリング４４で下方に付勢されたスプ
ール２０が上下移動自在に挿入され、このスプール２０
ＶＣは中央に上下に貫通する通孔４５と外周の環状溝４
６とが形成されている。A spool 20 biased downward by a spring 44 is inserted into the oil chamber 43 so as to be movable up and down.
VC has a through hole 45 that penetrates vertically in the center and an annular groove 4 on the outer periphery.
6 is formed.
スプール２００ランドはそれぞれバイパスＡたるピスト
ンロッド２の通孔３９α、３９ｂをそれぞれ上下動又は
中立時に開閉する。図の実施例ではスプリング４４で下
方に押し下げられた中立時に上方のランドが通孔３９α
を閉じている。The spool 200 land opens and closes the through holes 39α and 39b of the piston rod 2, which are the bypass A, respectively, when moving up and down or when in the neutral position. In the illustrated embodiment, the upper land is in the through hole 39α when the spring 44 pushes it down in the neutral state.
is closed.
スプール２０が若干上昇すると通孔３９α、３９ｂが環
状溝４６を介して連通し、スプール２ｏの位置に応じて
通孔３９α、３９ｈの開度が自動的に調整され、減衰力
もその開度に応じた大きさとなる。When the spool 20 rises slightly, the through holes 39α and 39b communicate through the annular groove 46, and the opening degrees of the through holes 39α and 39h are automatically adjusted according to the position of the spool 2o, and the damping force also corresponds to the opening degree. It will be the same size.
スプール２００通孔４５の下部出口にはわずかた切欠き
が形成されると共に出口シートにスプリングで上方に付
勢されたチェックバルブ２４が開閉自在に設けられてい
る。スプリングはスプール２０の下部に挿入されたスプ
リングシートで支えられている。A slight notch is formed at the lower outlet of the spool 200 through hole 45, and a check valve 24 biased upward by a spring is provided in the outlet seat so as to be openable and closable. The spring is supported by a spring seat inserted into the lower part of the spool 20.
圧力室２９内にはスプリング４７で下方に付勢されたポ
ペット型のプランジャ２７が上下移動自在に挿入され、
プランジャ２７の背部側たる下端には通孔Ｃを介して下
部油室７の内圧が作用し、この下部油室７の内圧の上昇
又は下降によりプランジャ２７が上下動する。A poppet-shaped plunger 27 biased downward by a spring 47 is inserted into the pressure chamber 29 so as to be movable up and down.
The internal pressure of the lower oil chamber 7 acts on the lower end of the back side of the plunger 27 through the through hole C, and the plunger 27 moves up and down as the internal pressure of the lower oil chamber 7 increases or decreases.
プランジャ２７は通常スプリング４７で最下方に押圧さ
れており、下部油室７の内圧が上昇するとスプリング４
７に抗して押し上げられ、この時、圧力室２９内の油が
通孔すよりスプール２０下方に導かれ、チェックバルブ
２４を通じると共に切欠きで絞られなから通孔４５より
リザーバ側の油室９に排出され、圧力室２９の内圧でス
プール２０が上昇する。他方、上記の状態かへ、下部油
室７の内圧が下降すると前記と逆にプランジャ２７が下
降し、圧力室２９の拡大に伴たってリザーバ側油室９の
油がチェックバルブ２４を開いて吸い込まれる。この時
、スプール２０は慣性があり、又スプリング４４を弱く
設定しておくことによりプランジャ２７の動きに対して
少し遅れて下降し、その際バイパスＡを開く。The plunger 27 is normally pressed downward by a spring 47, and when the internal pressure of the lower oil chamber 7 increases, the spring 4
7, and at this time, the oil in the pressure chamber 29 is guided below the spool 20 through the hole, passes through the check valve 24, and is not throttled by the notch, so that the oil in the reservoir side than the through hole 45 is pushed up. It is discharged into the chamber 9, and the spool 20 is raised by the internal pressure of the pressure chamber 29. On the other hand, when the internal pressure in the lower oil chamber 7 decreases to the above state, the plunger 27 descends in the opposite manner to the above, and as the pressure chamber 29 expands, the check valve 24 opens and the oil in the reservoir side oil chamber 9 is sucked in. It will be done. At this time, the spool 20 has inertia, and by setting the spring 44 weakly, the spool 20 descends with a slight delay relative to the movement of the plunger 27, and the bypass A is opened at this time.
以下作用を詳しく説明する。The action will be explained in detail below.
実施例によれば、油圧緩衝器に加わる振動で、そのシリ
ンダ１とピストン３との間の相対移動により、先ず、ピ
ストン３が作方向への変位を開始すると、これによって
上部油室６の室圧が高くなる。According to the embodiment, when the piston 3 first starts to be displaced in the operating direction due to the relative movement between the cylinder 1 and the piston 3 due to vibrations applied to the hydraulic shock absorber, the upper oil chamber 6 is thereby opened. Pressure increases.
その結果、上部油室６の作動油は、オｌの流路たるポー
ト３１を通りリーフバルブ３３を押し開き減衰力を発生
したから下部油室７に流入すると共に、ピストンロッド
２のシリンダｌ内からの退出によって該下部油室７内で
不足する作動油が外筒４内の油室からベースバルブ機構
のチエツク弁を開いて該下部油室７に流入する。As a result, the hydraulic oil in the upper oil chamber 6 flows into the lower oil chamber 7 through the port 31, which is the flow path of the piston rod 2, and pushes the leaf valve 33 open to generate a damping force. As a result, the insufficient hydraulic oil in the lower oil chamber 7 opens the check valve of the base valve mechanism from the oil chamber in the outer cylinder 4 and flows into the lower oil chamber 7.
これに対して、加振周波数感応の矛２の流路たるピスト
ンロッド２内では、それまで下部油室７の高い室圧によ
る作用圧を受はスプリング２７の拡圧力に抗して作動域
の上死点位置に占位していたプランジャ２７が、下部油
室７の室圧低下とスプリング２７の拡圧力とによって、
才２図の下方向に押されて、その受圧面が隔壁部材４２
の上端に当接する下死点位置に移動する。On the other hand, in the piston rod 2, which is the flow path of the excitation frequency-sensitive spear 2, the working pressure due to the high chamber pressure of the lower oil chamber 7 has been applied to the operating range against the expansion force of the spring 27. The plunger 27, which was located at the top dead center position, is now moved due to the lower pressure in the lower oil chamber 7 and the expansion force of the spring 27.
The pressure-receiving surface of the partition wall member 42 is pushed downward as shown in FIG.
Move to the bottom dead center position where it touches the top edge of.
この移動で、圧力室２９の室圧が低下することにたるの
で、油室９のリザーバー室圧を受けているチェックバル
ブ２４が付勢スプリングの作用力に抗して同じく下方向
に押し下げられ、通孔４５が開放され、これによって、
該圧力室２９内には油室９からの作動油が補充される。Due to this movement, the pressure in the pressure chamber 29 decreases, so the check valve 24, which receives the reservoir pressure in the oil chamber 9, is also pushed downward against the force of the biasing spring. The through hole 45 is opened, and thereby,
The pressure chamber 29 is replenished with hydraulic oil from the oil chamber 9.
次に、ピストン３が圧側方向への変位を開始すると、上
部油室６の室圧が逆に低下し下部油室７の室圧が高くな
るのでリーフバルブ３４を押し開いてのボート３２にお
ける矛１の流路と、外筒４内の油室に向かう作動油の戻
し流路とが形成される一方、プランジャ２７がその下端
面たる受圧面に下部油室７の高い室圧を受けてスプリン
グ４７の拡圧力に抗して、先の下死点位置から上方向に
押し上げられる。Next, when the piston 3 starts to move in the pressure side direction, the pressure in the upper oil chamber 6 decreases and the pressure in the lower oil chamber 7 increases. 1 flow path and a return flow path for the hydraulic oil toward the oil chamber in the outer cylinder 4 are formed, while the plunger 27 receives the high chamber pressure of the lower oil chamber 7 on its lower end surface, which is the pressure receiving surface, and generates a spring. 47, and is pushed upward from the previous bottom dead center position.
これによって、圧力室２９の室圧は、該プランジャ２７
の浸入による容積減り分に対応して上昇し、チェックバ
ルブ２４を上昇復帰させて先の通孔４５を閉じる。As a result, the pressure in the pressure chamber 29 is reduced by the plunger 27.
The check valve 24 rises in response to the volume reduction caused by the infiltration, and the check valve 24 returns to the upward position, thereby closing the previous through hole 45.
即ち、油圧緩衝器本体に対する１サイクルの加振によっ
て、これに応答するプランジャ２７の変位によるポンプ
作用で、圧力室２９には常に一定量の作動油が送り込ま
れ、しかも、この加振に対するプランジャ２７の応答性
は、加振速度の広い変化範囲で保たれる。That is, when the hydraulic shock absorber main body is subjected to one cycle of vibration, a certain amount of hydraulic oil is always fed into the pressure chamber 29 by the pump action caused by the displacement of the plunger 27 in response to the vibration, and furthermore, the pressure chamber 29 is constantly fed with a certain amount of hydraulic oil. The responsiveness is maintained over a wide range of excitation speed changes.
従って、該圧力室２９に送り込まれる作動油流量は、そ
の単位時間平均では加振周波数に比例することになる。Therefore, the flow rate of the hydraulic oil sent into the pressure chamber 29 is proportional to the excitation frequency on average per unit time.
そして、この圧力室２９の圧力を受けるスプール２０の
変位域における通孔３９α、３９ｈに達する部分のスプ
ール外周に、これ等の通孔３９ａ。These through holes 39a are formed on the outer periphery of the spool at a portion reaching the through holes 39α and 39h in the displacement region of the spool 20 that receives the pressure of the pressure chamber 29.
３９ｂ間を橋架する環状溝４６を設けておくことにより
、加振動作の低周波数域でのスプール変位におげろ通孔
３９ａ側の閉鎖状態（第３図（Ａ１図示）、同中間周波
数域のスプール変位での通孔３９１２ 、３９Ａの連結
絞り込み状態１’３図ＦＢ＋図示）、同高周波数域のス
プール変位での通孔３９Ｉ５側の閉鎖状態にｆ−３図ｆ
ｃ）図示）の各変位に対して、通孔３９α、３９ｂにお
ける通路開閉と絞り開口面積を第４図示ｆＡｌに示す如
く変化させることが出来る。By providing the annular groove 46 bridging between the grooves 39b and 39b, the closed state of the through hole 39a side (as shown in Fig. 3 (A1) and the intermediate frequency range of the spool displacement in the low frequency range of excitation operation) When the spool is displaced, the connected narrowing state of the through holes 3912 and 39A is 1'3 (Fig.
c) For each displacement shown in the figure, the passage opening/closing and the aperture opening area in the through holes 39α and 39b can be changed as shown in the fourth figure fAl.
しかして、この通孔３９α、３９ｂにより流量規制され
る矛３の流路では、加振下のピストン３の動作に対する
減衰力が、第５図ＦＢ＋に示す如く、加振周波数に応じ
て変化する。Therefore, in the flow path of the piston 3 where the flow rate is regulated by the through holes 39α and 39b, the damping force against the movement of the piston 3 under excitation changes depending on the excitation frequency, as shown in FIG. 5 FB+. .
尚、この矛２、矛３の流路における通路開閉並びに絞り
開口面積の変化は、前記スプール２０の移動占位状態に
おける通孔３９ａ、 ３９ｂの開口位置並びにそれ等の
形状によって決定されるもので、しかも、該スプール２
０が加振周波数に応じて移動するので、前記位置及び形
状の選択設定によって、この流路の周波数依存特性をハ
イカット、ローカット又は中間カットのいづれにも変換
することが出来る。Incidentally, the passage opening/closing and the change in the throttle opening area in the flow paths of the spears 2 and 3 are determined by the opening positions of the through holes 39a, 39b and their shapes when the spool 20 is in the moving position. , and the spool 2
0 moves in accordance with the excitation frequency, the frequency-dependent characteristic of this flow path can be converted to any of high-cut, low-cut, or intermediate-cut by selecting and setting the position and shape.
以上のように、この発明によれば、次の効果が得られる
。As described above, according to the present invention, the following effects can be obtained.
■加振周波数によって減衰力が変化する加振周波数依存
型の油圧緩衝器を得ることが出来る。■It is possible to obtain an excitation frequency-dependent hydraulic shock absorber whose damping force changes depending on the excitation frequency.
■絞り開口面積可変のためのスプールと流路開口部との
配置並びにそれ等の形状を適宜選択決定することにより
、任意の加振周波数の複数個所の領域で減衰力を低減さ
せ、他の領域において減衰力の増大を計ることも可能で
あルノテ、と刺を車輌用サスペンションに用いて従来の
両共振点周波数域で大きい減衰力を維持して、該サスペ
ンション系における共振動作を抑制し、且つ、それ以外
の周波数領域で減衰力を低下させて、接糸にソフトなス
プリング性能を発揮するショックアブソーバとすること
が出来る。■By appropriately selecting and determining the arrangement of the spool and flow path opening for variable aperture opening area, as well as their shapes, the damping force can be reduced in multiple regions of any excitation frequency, and other regions can be reduced. It is also possible to increase the damping force in the vehicle suspension by maintaining a large damping force in the conventional resonance frequency range, suppressing the resonance operation in the suspension system, and By reducing the damping force in other frequency ranges, it is possible to create a shock absorber that exhibits soft spring performance on the wept.
■スプールやプランジャをピストンロッド内に組み込ん
であるのでピストンが小型とたり、全体の基本長を短か
くできる。■Since the spool and plunger are built into the piston rod, the piston can be made smaller and the overall basic length can be shortened.
■周波数感応機構を設けたことにより通常の油圧緩衝器
のピストン構造にそれ程影響を与えず、り戸フバルブ剛
性などの設計が比較的自由である。■By providing a frequency sensitive mechanism, it does not have much effect on the piston structure of a normal hydraulic shock absorber, and the design of the valve rigidity etc. is relatively free.
矛１図はこの発明の一実施例に係る油圧緩衝器を示す縦
断面図、＋２図はそれぞれ減衰バルブ機構部分拡大して
示す縦断面図、第３図（Ａ）（ＢｌＦＣ＋はこの発明の
油圧緩衝器における周波数依存型流路構造部の各作動状
況を示す断面図、牙４図（Ａｌ（Ｂｌはこの発明の油圧
緩衝器にねける要部の作動特性図である。
１・・・シリンダ、２・・魯ピストンロッド１，３・・
・ピストン、４・・・外筒、６・・・土部油室、７・・
・下部油室、９・・・油室、２０・・・スプール、２４
・・・チェックバルブ、２７・・・プランジャ、２９・
・・圧力室、３９ａ、３９ｈ・・・通孔、Ａ・・◆バイ
パス。Figure 1 is a vertical cross-sectional view showing a hydraulic shock absorber according to an embodiment of the present invention, Figure +2 is a vertical cross-sectional view showing an enlarged portion of the damping valve mechanism, and Figure 3 (A) (BlFC+ is a hydraulic shock absorber according to an embodiment of the present invention). A cross-sectional view showing each operating situation of the frequency-dependent flow path structure in the shock absorber, Figure 4 (Al (Bl is a diagram showing the operating characteristics of the main parts in the hydraulic shock absorber of the present invention). 1... Cylinder , 2... Lu piston rod 1, 3...
・Piston, 4... Outer cylinder, 6... Dobe oil chamber, 7...
・Lower oil chamber, 9...Oil chamber, 20...Spool, 24
...Check valve, 27...Plunger, 29.
...Pressure chamber, 39a, 39h...Through hole, A...◆Bypass.
Claims (1)
在に挿入され、ピストンはシリンダ内に上下二つの油室
を区画し、二つの油室はピストンに設けた伸ポートと圧
ポートと各ポートの出口端にそれぞれ設けた伸リーフバ
ルブと圧リーフバルブを介して開閉される油圧緩衝器に
於て、ピストンロッド内の上方にリザーバを設け、同じ
くピストンロッド内の下方に圧力室を設け、リザーバと
圧力室との間に一方向に付勢されたスプールを上下移動
自在に挿入すると共に当該スプールにはリザーバと圧力
室を通じさせるポートを形成し、スプール内の圧力室側
ポート出口にはチェックバルブが開閉自在に設けられ、
前記圧力室内には一方向に付勢されたプランジャが上下
移動自在に設けられ、プランジャの背部側は通孔を介し
て下部油室に開口し、更にピストンとピストンロッドに
は上下二つの油室を連通するバイパスを設け、当該バイ
パスは前記スプールの上下動に伴なつて開閉される油圧
緩衝器。A piston rod is movably inserted into the cylinder via a piston, and the piston divides the cylinder into two upper and lower oil chambers. In the hydraulic shock absorber, which is opened and closed via an expansion leaf valve and a pressure leaf valve, respectively, a reservoir is provided above the piston rod, and a pressure chamber is also provided below the piston rod, and the reservoir and pressure chamber are connected to each other. A spool biased in one direction is inserted between the spool so as to be movable up and down, and a port is formed in the spool to communicate between the reservoir and the pressure chamber, and a check valve is provided at the outlet of the pressure chamber side port in the spool so that it can be opened and closed. established in
A plunger biased in one direction is provided in the pressure chamber so as to be movable up and down, and the back side of the plunger opens into a lower oil chamber through a through hole, and the piston and piston rod are provided with two oil chambers, upper and lower. A hydraulic shock absorber is provided with a bypass that communicates with the spool, and the bypass is opened and closed as the spool moves up and down.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21660489A JP2909749B2 (en) | 1989-08-23 | 1989-08-23 | Hydraulic shock absorber |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21660489A JP2909749B2 (en) | 1989-08-23 | 1989-08-23 | Hydraulic shock absorber |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0379831A true JPH0379831A (en) | 1991-04-04 |
| JP2909749B2 JP2909749B2 (en) | 1999-06-23 |
Family
ID=16691029
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21660489A Expired - Fee Related JP2909749B2 (en) | 1989-08-23 | 1989-08-23 | Hydraulic shock absorber |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2909749B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0349443U (en) * | 1989-09-20 | 1991-05-14 | ||
| EP0591205A1 (en) * | 1991-07-02 | 1994-04-13 | Richardson Technology, Ltd. | Self-contained automatic terrain condition adjusting shock absorber |
| US8245822B2 (en) | 2008-07-16 | 2012-08-21 | Mando Corporation | Amplitude selective shock absorber |
| US8333270B2 (en) | 2008-07-16 | 2012-12-18 | Mando Corporation | Floating piston valve of amplitude selective shock absorber |
-
1989
- 1989-08-23 JP JP21660489A patent/JP2909749B2/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0349443U (en) * | 1989-09-20 | 1991-05-14 | ||
| EP0591205A1 (en) * | 1991-07-02 | 1994-04-13 | Richardson Technology, Ltd. | Self-contained automatic terrain condition adjusting shock absorber |
| EP0591205A4 (en) * | 1991-07-02 | 1995-07-26 | Ricor Inc | Self-contained automatic terrain condition adjusting shock absorber. |
| US8245822B2 (en) | 2008-07-16 | 2012-08-21 | Mando Corporation | Amplitude selective shock absorber |
| US8333270B2 (en) | 2008-07-16 | 2012-12-18 | Mando Corporation | Floating piston valve of amplitude selective shock absorber |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2909749B2 (en) | 1999-06-23 |
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| LAPS | Cancellation because of no payment of annual fees |