JP3764236B2 - Hydraulic cylinder tuning device - Google Patents

Hydraulic cylinder tuning device Download PDF

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JP3764236B2
JP3764236B2 JP03063297A JP3063297A JP3764236B2 JP 3764236 B2 JP3764236 B2 JP 3764236B2 JP 03063297 A JP03063297 A JP 03063297A JP 3063297 A JP3063297 A JP 3063297A JP 3764236 B2 JP3764236 B2 JP 3764236B2
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pressure oil
plunger
hydraulic
oil chamber
cylinder
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JPH10226496A (en
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俊次 磯貝
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株式会社スギヤス
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
    • F15B11/22—Synchronisation of the movement of two or more servomotors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/06—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with two or more servomotors
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F7/00—Lifting frames, e.g. for lifting vehicles; Platform lifts
    • B66F7/06—Lifting frames, e.g. for lifting vehicles; Platform lifts with platforms supported by levers for vertical movement
    • B66F7/08—Lifting frames, e.g. for lifting vehicles; Platform lifts with platforms supported by levers for vertical movement hydraulically or pneumatically operated
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/71—Multiple output members, e.g. multiple hydraulic motors or cylinders

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Forklifts And Lifting Vehicles (AREA)

Description

【０００１】
【発明の属する技術分野】
本発明は、自動車整備用リフト等複数の油圧シリンダを用いた油圧回路に設けられ、前記各油圧シリンダを同調して駆動させる同調装置に関する。
【０００２】
【従来の技術】
例えば油圧シリンダを夫々備えた一対のリフトで自動車を昇降させる自動車整備用リフト等の油圧回路においては、車両の偏荷重により左右のリフトに段差が発生しないように、両油圧シリンダと油圧源との間にシンクロナイズシリンダを介在させた同調装置が構成される。これは油圧源からの圧油の供給により往動するプランジャやロッド等に１以上のピストン部を設けると共に、このピストン部やプランジャ等の前方に夫々等しい断面積の圧油室を形成し、これらの圧油室を夫々油圧シリンダに接続したもので、プランジャ等を往動させた場合には、各圧油室から夫々対応する油圧シリンダへ等量の圧油が送られて、油圧シリンダの同調が得られるようになっている。
【０００３】
【発明が解決しようとする課題】
一方リフトの下降（油圧シリンダとシンクロナイズシリンダの復動）は、荷重等によって油圧シリンダに加えられる外力に頼るものが多く、外力が小さいか或はない場合は、シンクロナイズシリンダ内部の抵抗により作動性が悪くなり、リフト側では下降動作が非常に遅いか、或は全く下降しない状態が生じる。そこでこのような場合に強制下降させる機構として、実開昭５５−１４０８０４号公報や実開昭６１−１０４８０４号公報には、シンクロナイズシリンダの外部に別のシリンダを設けて両シリンダのロッドを連結し、この外部シリンダの駆動によってシンクロナイズシリンダのロッドを復動させる構成が開示されている。よってこれらの構成によれば、シンクロナイズシリンダのスムーズな復動（リフトで言えば強制下降）が得られるが、反面外部シリンダの採用により、シンクロナイズシリンダアッセンブリが大型化してコストアップに繋がり、シリンダサイズや油圧ユニットのレイアウトにも制限を受けてしまう。又ロッドが外部へ露出するため、塵埃やエア等が混入しやすく、耐久性や作動性等性能の低下を招く虞れもある。
一方特に自動車整備用リフトにおいては、上記シンクロナイズシリンダを採用しても、油漏れ等により左右の油圧シリンダが同調せず、リフト間の傾きや、ストロークエンドへの未到達によるリフトの揚程不足等を生じさせる場合があるが、これを修正するには、手動によるか、自動でも一旦リフトを最上限まで上昇させる必要があり、非常に面倒となっている。
【０００４】
そこで請求項１に記載の発明は、シンクロナイズシリンダの復動動作を確実に行うことができるのは勿論、その構成を合理的に構成してコストアップを抑え、シリンダサイズの設定にも影響を与えない油圧シリンダの同調装置を提供することを目的としたものである。
【０００５】
【課題を解決するための手段】
上記目的を達成するために、請求項１に記載の発明は、前記シンクロナイズシリンダに、前記プランジャ内部に形成された復動用圧油室と、前記プランジャ往動側の圧油室内にあって前記油圧源に接続される油路を内設して復動側へ突設され、前記プランジャに同軸で挿通して前記油路を前記復動用圧油室と連通させた固定プランジャとからなる復動機構を内設し、前記油圧源から前記固定プランジャへの圧油の供給により前記プランジャに復動方向への油圧を付与可能としたことを特徴とするものである。
又請求項２に記載の発明は、請求項１の目的に加えて、上記油漏れ等による油圧シリンダの不同調等に効果的に対処するために、前記シンクロナイズシリンダに、前記プランジャの所定の往復動位置で前記各圧油室同士を連通させ、各圧油室の油量を適性量に補正して均等化させる補正管路を設けたものである。
【０００６】
【発明の実施の形態】
以下本発明を自動車整備用リフトに適用した実施の形態を図面に基づいて説明する。
図１に示すように、自動車整備用リフトは左右２台のリフタ１ａ，１ｂを備え、各リフタ１ａ，１ｂの昇降台は、夫々Ｘ形伸縮機構２ａ，２ｂにより昇降可能に支持されると共に、油圧シリンダ３ａ，３ｂによって駆動される。この両油圧シリンダ３ａ，３ｂは、シンクロナイズシリンダ５と油圧ユニット３０とで構成される同調装置４に組み込まれて並列に接続され、油圧ユニット３０からの圧油の供給により、油圧シリンダ３ａ，３ｂはシンクロナイズシリンダ５を介して同調して伸縮し、左右のリフタ１ａ，１ｂを昇降させるようになっている。
又シンクロナイズシリンダ５は、略中央に備えた隔壁６を挟んで右側が小径、左側が大径となる圧油室を夫々形成したシリンダチューブ７と、前記隔壁６を貫通して軸方向に進退可能で、後端（同図の左側）にピストン８を備えたプランジャ９とから構成される。このプランジャ９は、シリンダチューブ７の小径側の圧油室及び及び隔壁６の内孔に摺接する一方、後方のピストン８が、シリンダチューブ７の大径側の圧油室に摺接する形態となっており、シリンダチューブ７の大径側において、ピストン８の後面に第一圧油室１０、ピストン８の前面に第二圧油室１１、そして小径側において、プランジャ９の前方に第三圧油室１２を夫々形成している。更に第三圧油室１２内においては、第三圧油室１２の前面からプランジャ９へ向けて、プランジャ９と同軸の固定プランジャ１４が突設されており、この固定プランジャ１４の先端が、プランジャ９の前面を貫通してプランジャ９内に形成された第四圧油室１３内へ突出している。
【０００７】
ここで各圧油室間の寸法関係を説明する。ここでは第二圧油室１１の断面積と、第三圧油室１２の断面積とを等しく設定している。よって第二圧油室１１の直径をｄ1 、プランジャ９の直径をｄ2 、固定プランジャ１４の直径をｄ3 とし、第一圧油室１０の断面積をＡO 、第二圧油室１１の断面積をＡ1 、第三圧油室１２の断面積をＡ2 、固定プランジャ１４の断面積をＡ3 とすると、

Figure 0003764236
となる。よってＡO ＝Ａ1 ＋Ａ2 ＋Ａ3 となるが、Ａ1 ＝Ａ2 の設定により、
ＡO ＝２Ａ1 ＋Ａ3 の関係が得られる。又ここから、
Figure 0003764236
ともなる。
【０００８】
一方シリンダチューブ７の大径側においては、第一圧油室１０への圧油の出入口１０ａが、第一管路１５によって油圧ユニット３０の圧油供給管３２及び戻り管３７に夫々接続されると共に、第二圧油室１１への圧油の出入口１１ａが、第二管路１６によって油圧シリンダ３ａに接続されている。又小径側においては、第三圧油室１２への圧油の出入口１２ａが、第三管路１７によって油圧シリンダ３ｂに接続されると共に、固定プランジャ１４の内部に設けられ、第四圧油室１３への圧油の出入口となる圧油路１９が、第四管路１８によって油圧ユニット３０の切換弁３４へ接続されている。更にシリンダチューブ７の大径側には、常態では閉弁し、ピストン８との当接により開弁する第一補正バルブ２０と第二補正バルブ２１とが夫々設けられる一方、小径側にも、常態では閉弁し、プランジャ９との当接により開弁する第三補正バルブ２２と第四補正バルブ２３とが夫々設けられる。ここでは第一補正バルブ２０と第三補正バルブ２２とは、補正管路２４によって互いに接続されるが、この補正管路２４は第二管路１６と交わって連通している。又第二補正バルブ２１は、補正管路２５によって第三圧油室１２に設けられたもう一つの出入口１２ｂと接続され、第四補正バルブ２３は、補正管路２６によって油圧ユニット３０の圧油供給管３２と接続されている。
尚上記第一管路１５における第一圧油室１０の出入口１０ａ付近と、第二、第三管路１６，１７における各油圧シリンダ３ａ，３ｂへの接続際とには、ヒューズ弁２７，２７・・が夫々設けられ、管路の破裂等の際の油圧シリンダ３ａ，３ｂの急激な下降を防止している。又第二、第三管路１６，１７には、後述するリフタ１ａ，１ｂの段差補正時に機能する安全弁２８，２８が夫々設けられている。一方第二、第三圧油室１１，１２には、エア抜きバルブ２９，２９が夫々備えられている。
そして油圧ユニット３０において、第一管路１５とオイルタンク３１間に設けられる圧油供給管３２には、上流側から、ポンプ３３、切換弁３４、逆止弁３５が夫々備えられると共に、ポンプ３３と切換弁３４との間には、リリーフ弁３６が設けられている。同じく第一管路１５とオイルタンク３１間に設けられる戻り管３７には、上流側から、流量制御弁３８と、切換弁３４と連動する下降弁３９が夫々設けられている。尚前記第四管路１８は、切換弁３４を介してオイルタンク３１に接続されている。
【０００９】
次に以上のように構成された同調装置４の作動を説明する。まず上昇時は、ポンプ３３を駆動させると、圧油は図１の位置の切換弁３４、逆止弁３５を介して第一管路１５から第一圧油室１０へ供給され、プランジャ９を前方へ押し出す。これにより第二圧油室１１及び第三圧油室１２は体積が狭まるため、第二圧油室１１の作動油は、出入口１１ａから第二管路１６へ流れて油圧シリンダ３ａへ送られ、同様に第三圧油室１２の作動油は、出入口１２ａから第三管路１７へ流れて油圧シリンダ３ｂへ送られる。ここで第二圧油室１１と第三圧油室１２との断面積は等しいため、油量が等しくなる油圧シリンダ３ａ，３ｂは同調して作動し、両リフタ１ａ，１ｂは同じ動きで上昇する。
一方下降時は、切換弁３４及び下降弁３９を同時に下降側へ切り換えることで、圧油は第四管路１８から固定プランジャ１４内の圧油路１９を介して第四圧油室１３に供給されるため、この圧油路１９の断面積×油圧の力がプランジャ９に作用する。又荷重により油圧シリンダ３ａ，３ｂへ加わる油圧も、第二管路１６から第二圧油室１１を介して、及び第三管路１７から第三圧油室１２を介して夫々ピストン８及びプランジャ９に作用するため、双方の合力によってピストン８を後退させることになる。更に第一圧油室１０の作動油は、下降弁３９の切り換えにより、第一管路１５から戻り管３７を通ってオイルタンク３１に戻るが、このとき流量制御弁３８により戻り管３７を流れる油量が一定化されるため、両リフタ１ａ，１ｂに加わる荷重に変動があっても両リフタ１ａ，１ｂの下降速度は変化しない。勿論両リフタ１ａ，１ｂに加わる荷重が０であっても、圧油路１９から第四圧油室１３へ送られる圧油により、下降速度が遅くなることはない。
ちなみに初期設定時、即ち上記リフタ１ａ，１ｂを初めて作動させる際は、第二圧油室１１、第三圧油室１２に空気が入っているため、まずリフタ１ａ，１ｂに車両等を載せないで上昇操作を行う。するとプランジャ９は最前進位置に達し、第三、第四補正バルブ２２，２３を夫々開弁させるため、ポンプ３３からの圧油は、補正管路２６を介して第四補正バルブ２３から第三圧油室１２へ送られ、そして第三管路１７から油圧シリンダ３ｂへ送られて、リフタ１ｂを上昇させる。同時に第三圧油室１２の圧油は、第三補正バルブ２２、補正管路２４、第二管路１６を介して第二圧油室１１及び油圧シリンダ３ａへ送られ、リフタ１ａを上昇させる。ここでエア抜きバルブ２９，２９によりエアを抜きながら上昇、下降を数回繰り返せば、第二、第三圧油室１１，１２内の空気は完全に抜かれ、夫々作動油が満たされる。尚第四圧油室１３の空気は、上昇時に圧油路１９から第四管路１８、切換弁３４を通ってオイルタンク３１に送られ、大気へ放出されるため、上昇、下降の繰り返しでエア抜きは完了することになる。
【００１０】
このように上記同調装置４においては、シンクロナイズシリンダ５のプランジャ９に、第四圧油室１３や固定プランジャ１４等の復動機構を採用したことで、油圧シリンダ３ａ，３ｂの下降動作が、荷重の有無やその荷重の大小に拘わりなく、定速で確実に行える。勿論低温時に油の粘度が上がっても下降速度には影響はない。又外部シリンダ等を用いず、シンクロナイズシリンダ５に同機構を内蔵したことで、▲１▼シンクロナイズシリンダ５の小型化、軽量化が達成でき、コストアップが抑制される共に、故障の発生が少なくなって高い信頼性も得られる。▲２▼設置の方向や位置の設定に制約を受けず、油圧ユニットのレイアウトがしやすくなって回路全体の小型化も図れる。▲３▼外気に触れる部分がないために塵埃やエア等の混入がなく、確実な動作と耐久性の向上が期待できる、といった効果が奏される。
特に本形態によれば、先に説明した寸法関係、即ち第一圧油室の断面積ＡO ＞第二圧油室の断面積Ａ1 ＋第三圧油室の断面積Ａ2 と、第二圧油室の断面積Ａ1 ＝第三圧油室の断面積Ａ2 という関係から、第一圧油室１０に加えられた一次油圧より、第二、第三圧油室１１，１２で発生する二次油圧の方が高くなること（増圧効果）で、各油圧シリンダ３ａ，３ｂに発生する推力はより強大となる。換言すれば、同じ推力を得るもので比較すると、本形態の油圧シリンダ３ａ，３ｂをより細く形成できることになり、延いてはリフタ１ａ，１ｂの一層の低床化が達成可能となる。
又上記のような寸法関係によれば、各圧油室間の面積比が大きく、下降時の第二、第三管路１１，１２及び第一圧油室１０の油圧が低く抑えられるため、途中で下降操作を中止した際の圧油の圧縮反発が小さくなり、リフタ１ａ，１ｂの跳ね上がりショックを小さくできる効果が得られる。一方Ｘ形伸縮機構２ａ，２ｂには、通常ラックと係止爪等の降下止め安全装置が備えられるが、仮に係止爪とラックとの係止状態で下降操作を行っても、安全装置に余分な力が加わらないため、リフタ側に余分な強度を付与させる必要がなくなる。よってコストアップを防止でき、リフタの低床化にも繋がる。
【００１１】
そして本形態において更に特徴的な補正の作用について、以下ケース毎に説明する。
補正１（第二、第三圧油室１１，１２の両方又は一方の作動油が減り、両リフタ１ａ，１ｂに揚程不足又は段差が生じた場合）
まず上限で補正する場合は、両リフタ１ａ，１ｂの上昇操作をして、プランジャ９を最前方位置まで移動させると、プランジャ９が第三、第四補正バルブ２２，２３に当接し、両補正バルブを開弁させる。そのまま上昇操作を継続すると、圧油は満状態となる第一圧油室１０には送られず、補正管路２６と第四補正バルブ２３を介して第三圧油室１２へ送られる。そして第三圧油室１２の圧油は、出入口１２ａ、第三管路１７から油圧シリンダ３ｂに送られると共に、第三補正バルブ２２から補正管路２４、第二管路１６から油圧シリンダ３ａにも送り込まれる。よってプランジャ９が停止しても、両油圧シリンダ３ａ，３ｂはストロークエンドまで作動して圧油は満状態となり、両リフタ１ａ，１ｂの段差が補正される。
補正２
補正１と同じケースで、下限で補正する場合は、下降操作を行い、プランジャ９を最後退位置まで移動させると、ピストン８が第一、第二補正バルブ２０，２１に当接し、両補正バルブを開弁させる。そのまま下降操作を継続すると、両リフタ１ａ，１ｂ及び両油圧シリンダ３ａ，３ｂが夫々下限に達し、油圧シリンダ３ａ，３ｂ側からの作動油の戻りがなくなるため、第二、第三圧油室１１，１２は真空状態となる。このとき下降弁３９も開弁しているから、オイルタンク３１の作動油は、戻り管３７から第一管路１５を経て第一圧油室１０へ入り、更に第一補正バルブ２０から補正管路２４、第二管路１６を介して第二圧油室１１へ大気圧によって送り込まれる。同様に第一圧油室１０へ入った作動油は、第二補正バルブ２１、補正管路２５、出入口１２ｂを介して第三圧油室１２へも大気圧によって送り込まれる。よって第二、第三圧油室１１，１２共に作動油が満たされ、リフタ１ａ，１ｂの段差が補正される。
【００１２】
補正３（第二、第三圧油室１１，１２の一方又は両方の圧油が増え、リフタ１ａ，１ｂに段差又は下限未到達が生じた場合）
まず上限で補正をする場合、上昇操作を行い、リフタ１ａ，１ｂのどちらかが上限に達するまで作動させる。このときプランジャ９は最前進位置には至らない。ここでリフタ１ｂが先に上限に達した際には、第三圧油室１２内の油圧が、ポンプ３３で発生する最大油圧の約２倍にまで高まる。すると第三補正バルブ２２がリリーフ弁として働き、開弁して補正管路２４、第二管路１６からリフタ１ａ側の油圧シリンダ３ａへ圧油を送り、リフタ１ａを上限まで上昇させる。同時に第三管路１７に接続される安全弁２８も作動して同管路１７内の油圧を減圧させる。よって第二、第三圧油室１１，１２間の圧力均衡がとられ、異常高圧の発生が防止されると共に、段差も補正される。その後はポンプ３３からの圧油は、圧油供給管３２と戻り管３７、及びオイルタンク３１間を環流するに止まる。
一方リフタ１ａが先に上限に達した際には、前記と同様に増圧効果でリフタ１ａ側の油圧が異常高圧となるが、この場合第二管路１６に接続された安全弁２８によって異常高圧は開放され、装置の破損防止と段差補正とを行うことができる。
補正４
補正３と同じケースで、下限で補正する場合は、まず下降操作を行ってプランジャ９を最後退位置に移動させる。このときリフタ１ａ，１ｂは共に下限位置には至らない。しかしピストン８は第一、第二補正バルブ２０，２１を開弁させるため、リフタ１ａ，１ｂの自重で両油圧シリンダ３ａ，３ｂに発生する油圧により、油圧シリンダ３ａの作動油は、第二管路１６、補正管路２４、第一補正バルブ２０、第一圧油室１０、第一管路１５を介し、戻り管３７からオイルタンク３１へ放出される。同様に油圧シリンダ３ｂの作動油は、第三管路１７、第三圧油室１２、補正管路２５、第二補正バルブ２１、第一圧油室１０、第一管路１５を介して、戻り管３７からオイルタンク３１へ放出される。よって両リフタ１ａ，１ｂを下限まで下げることができ、段差が解消される。
【００１３】
このように本形態によれば、リフタ１ａ，１ｂの段差補正や上下限未到達が、リフタ１ａ，１ｂの上下限位置に拘わらず可能となる。特に単純な上昇或は下降操作のみ行えば補正される構成であるから、ユーザーは補正のための特別な操作を行わなくても、リフタの使用中に自動的に段差が解消されることになり、良好な使い勝手が得られる。
尚リフタ間の段差は、上記ケースのように圧油室内の油量に起因して生じる他、リフタ下降中に昇降台が障害物に当たり、片方のみ下降が阻止されるような場合にも起こり得る。しかし本形態においては、油圧シリンダの反対側に油圧を加えて強制下降させる従来の方法に比べて、油圧シリンダ間の差圧は簡単に現われるため、この差圧を検知するセンサーを組み込めば、左右の段差検知を簡単に行うことができ、このケースでも段差の発生を未然に防ぐことが可能となる。
【００１４】
尚上記実施の形態では、１つのピストンを設けたプランジャを用い、ピストンの前方とプランジャの前方とに夫々圧油室を設けて、夫々接続された２本の油圧シリンダを同調させる構成で説明したが、上記ピストンを軸方向に複数並設して、各ピストン間に断面積の等しい圧油室を夫々形成すると共に、これらの圧油室を油圧シリンダに夫々接続して、３本以上の油圧シリンダを同調させる形態でも、上記と同様に固定プランジャ等による復動機構の採用は可能である。
【００１５】
【発明の効果】
請求項１に記載の発明によれば、シンクロナイズシリンダに前記復動機構を内蔵したことで、油圧シリンダの下降動作が、荷重の有無やその荷重の大小に拘わりなく、定速で確実に行える。勿論低温時に油の粘度が上がっても下降速度には影響はない。又シンクロナイズシリンダの小型化、軽量化が達成でき、コストアップが抑制される共に、故障の発生が少なくなって高い信頼性も得られる。更に設置の方向や位置の設定に制約を受けず、油圧ユニットのレイアウトがしやすくなって回路全体の小型化も図れる。加えて外気に触れる部分がないために塵埃やエア等の混入がなく、確実な動作と耐久性の向上が期待できる。特に、前記復動用圧油室と固定プランジャとの採用により復動機構が簡単に構成でき、コストアップの一層の抑制に繋がる。
又請求項２に記載の発明によれば、請求項１の効果に加えて、補正管路の採用により、油漏れ等で各圧油室間の油量が相違し、油圧シリンダの不同調やストロークエンドへの未到達が生じることがあっても、これを効果的に補正して油圧シリンダの適正な往復動作を維持することができる。特にこの補正はプランジャの所定の往復動位置で行われるものであるから、補正のための特別の操作を要することなく、油圧シリンダの通常の使用で自動的に補正がなされ、使い勝手は良好となる。
【図面の簡単な説明】
【図１】自動車整備用リフトに設けられた油圧シリンダの同調装置の説明図である。
【符号の説明】
１ａ，１ｂ・・リフタ、２ａ，２ｂ・・Ｘ形伸縮機構、３ａ，３ｂ・・油圧シリンダ、４・・同調装置、５・・シンクロナイズシリンダ、７・・シリンダチューブ、８・・ピストン、９・・プランジャ、１０・・第一圧油室、１１・・第二圧油室、１２・・第三圧油室、１３・・第四圧油室、１４・・固定プランジャ、１５・・第一管路、１６・・第二管路、１７・・第三管路、１８・・第四管路、２０・・第一補正バルブ、２１・・第二補正バルブ、２２・・第三補正バルブ、２３・・第四補正バルブ、３０・・油圧ユニット、３１・・オイルタンク、３３・・ポンプ、３４・・切換弁。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tuning device that is provided in a hydraulic circuit using a plurality of hydraulic cylinders, such as an automobile maintenance lift, and that drives each of the hydraulic cylinders in a synchronized manner.
[0002]
[Prior art]
For example, in a hydraulic circuit such as an automobile maintenance lift that lifts and lowers an automobile with a pair of lifts each having a hydraulic cylinder, the hydraulic cylinder and the hydraulic power source must be A tuning device with a synchronized cylinder interposed therebetween is constructed. This is because one or more piston parts are provided on a plunger or rod that moves forward by the supply of pressure oil from a hydraulic power source, and a pressure oil chamber having an equal cross-sectional area is formed in front of each piston part and plunger. Each pressure oil chamber is connected to a hydraulic cylinder. When a plunger or the like is moved forward, an equal amount of pressure oil is sent from each pressure oil chamber to the corresponding hydraulic cylinder to synchronize the hydraulic cylinder. Can be obtained.
[0003]
[Problems to be solved by the invention]
On the other hand, the lowering of the lift (returning of the hydraulic cylinder and the synchronizing cylinder) often depends on the external force applied to the hydraulic cylinder by a load or the like, and if the external force is small or not, the operability is reduced by the resistance inside the synchronizing cylinder. On the lift side, the descending operation is very slow or does not descend at all. Therefore, as a mechanism for forcibly lowering in such a case, Japanese Utility Model Laid-Open Nos. 55-140804 and 61-104804 disclose that another cylinder is provided outside the synchronized cylinder and the rods of both cylinders are connected. A configuration is disclosed in which the rod of the synchronization cylinder is moved back by driving the external cylinder. Therefore, according to these configurations, the smooth return of the synchronized cylinder (forced lowering in terms of lift) can be obtained. On the other hand, the use of an external cylinder increases the size of the synchronized cylinder assembly, leading to an increase in cost, The layout of the hydraulic unit is also limited. Further, since the rod is exposed to the outside, dust, air, and the like are likely to be mixed, and there is a possibility that performance such as durability and operability may be deteriorated.
On the other hand, especially in automobile maintenance lifts, the left and right hydraulic cylinders do not synchronize due to oil leaks, etc., even if the above-mentioned synchronization cylinder is used, causing tilt between lifts and insufficient lift of the lift due to failure to reach the stroke end. In order to correct this, it is necessary to raise the lift to the upper limit once manually or automatically, which is very troublesome.
[0004]
Therefore, the invention described in claim 1 can reliably perform the backward operation of the synchronized cylinder, and can rationally configure the structure to suppress the cost increase and affect the setting of the cylinder size. It is intended to provide a hydraulic cylinder tuning device that does not.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the invention according to claim 1 is characterized in that the synchronizing cylinder is provided with a hydraulic oil chamber for return movement formed in the plunger and a hydraulic oil chamber on the forward side of the plunger, and the hydraulic pressure A return mechanism comprising an oil passage connected to the power source and projecting toward the backward movement side, and a fixed plunger which is coaxially inserted into the plunger and communicates the oil passage with the pressure oil chamber for backward movement. And hydraulic pressure in the backward movement direction can be applied to the plunger by supplying pressure oil from the hydraulic pressure source to the fixed plunger .
According to a second aspect of the present invention, in addition to the object of the first aspect, in order to effectively cope with the hydraulic cylinder non-synchronization due to the oil leakage or the like, a predetermined reciprocation of the plunger is provided in the synchronization cylinder. The pressure oil chambers are communicated with each other at the moving position, and a correction pipe for correcting the oil amount in each pressure oil chamber to an appropriate amount and equalizing it is provided.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments in which the present invention is applied to an automobile maintenance lift will be described below with reference to the drawings.
As shown in FIG. 1, the lift for automobile maintenance is provided with two lifters 1a and 1b on the left and right sides, and the lifts of the lifters 1a and 1b are supported by the X-type expansion / contraction mechanisms 2a and 2b so as to be lifted and lowered, respectively. It is driven by hydraulic cylinders 3a and 3b. Both hydraulic cylinders 3a and 3b are incorporated in a synchronizing device 4 composed of a synchronizing cylinder 5 and a hydraulic unit 30 and connected in parallel. When hydraulic oil is supplied from the hydraulic unit 30, the hydraulic cylinders 3a and 3b are The left and right lifters 1a and 1b are moved up and down in synchronization with each other via the synchronize cylinder 5.
The synchronize cylinder 5 can be advanced and retracted in the axial direction through a cylinder tube 7 formed with a pressure oil chamber having a small diameter on the right side and a large diameter on the left side with a partition wall 6 provided substantially in the center, and through the partition wall 6. And a plunger 9 having a piston 8 at its rear end (left side in the figure). The plunger 9 is in sliding contact with the pressure oil chamber on the small diameter side of the cylinder tube 7 and the inner hole of the partition wall 6, while the rear piston 8 is in sliding contact with the pressure oil chamber on the large diameter side of the cylinder tube 7. The first pressure oil chamber 10 on the rear surface of the piston 8 on the large diameter side of the cylinder tube 7, the second pressure oil chamber 11 on the front surface of the piston 8, and the third pressure oil on the front side of the plunger 9 on the small diameter side. Each chamber 12 is formed. Further, in the third pressure oil chamber 12, a fixed plunger 14 coaxial with the plunger 9 is projected from the front surface of the third pressure oil chamber 12 toward the plunger 9, and the tip of the fixed plunger 14 is connected to the plunger. 9 protrudes into the fourth pressure oil chamber 13 formed in the plunger 9 through the front surface.
[0007]
Here, the dimensional relationship between the pressure oil chambers will be described. Here, the cross-sectional area of the second pressure oil chamber 11 and the cross-sectional area of the third pressure oil chamber 12 are set equal. Therefore, the diameter of the second pressure oil chamber 11 is d 1 , the diameter of the plunger 9 is d 2 , the diameter of the fixed plunger 14 is d 3 , the cross-sectional area of the first pressure oil chamber 10 is A O , and the second pressure oil chamber 11. Where A 1 is the cross-sectional area, A 2 is the cross-sectional area of the third pressure oil chamber 12, and A 3 is the cross-sectional area of the fixed plunger 14.
Figure 0003764236
It becomes. Therefore, A O = A 1 + A 2 + A 3 , but by setting A 1 = A 2 ,
A relationship of A O = 2A 1 + A 3 is obtained. From here,
Figure 0003764236
It also becomes.
[0008]
On the other hand, on the large diameter side of the cylinder tube 7, the pressure oil inlet / outlet port 10 a to the first pressure oil chamber 10 is connected to the pressure oil supply pipe 32 and the return pipe 37 of the hydraulic unit 30 by the first pipe line 15, respectively. At the same time, a pressure oil inlet / outlet port 11 a to the second pressure oil chamber 11 is connected to the hydraulic cylinder 3 a by a second pipe line 16. On the small-diameter side, the pressure oil inlet / outlet 12a to the third pressure oil chamber 12 is connected to the hydraulic cylinder 3b by the third pipe line 17 and provided inside the fixed plunger 14 to provide a fourth pressure oil chamber. A pressure oil passage 19 serving as an inlet / outlet of pressure oil to 13 is connected to a switching valve 34 of the hydraulic unit 30 by a fourth pipe 18. Further, on the large diameter side of the cylinder tube 7, a first correction valve 20 and a second correction valve 21 that are normally closed and opened by contact with the piston 8 are provided, respectively, while also on the small diameter side, In a normal state, a third correction valve 22 and a fourth correction valve 23 that are closed and opened by contact with the plunger 9 are provided. Here, the first correction valve 20 and the third correction valve 22 are connected to each other by a correction pipe line 24, and the correction pipe line 24 intersects and communicates with the second pipe line 16. The second correction valve 21 is connected to another inlet / outlet 12b provided in the third pressure oil chamber 12 by a correction pipe 25, and the fourth correction valve 23 is connected to the pressure oil of the hydraulic unit 30 by a correction pipe 26. The supply pipe 32 is connected.
It should be noted that fuse valves 27, 27 are provided in the vicinity of the inlet / outlet port 10 a of the first pressure oil chamber 10 in the first pipe line 15 and when connected to the hydraulic cylinders 3 a, 3 b in the second and third pipe lines 16, 17. .. Are provided to prevent sudden lowering of the hydraulic cylinders 3a and 3b in the event of a pipe rupture or the like. The second and third pipes 16 and 17 are provided with safety valves 28 and 28, respectively, which function when level differences of lifters 1a and 1b described later are corrected. On the other hand, the second and third pressure oil chambers 11 and 12 are provided with air vent valves 29 and 29, respectively.
In the hydraulic unit 30, a pressure oil supply pipe 32 provided between the first pipe line 15 and the oil tank 31 is provided with a pump 33, a switching valve 34, and a check valve 35 from the upstream side. A relief valve 36 is provided between the control valve 34 and the switching valve 34. Similarly, a return pipe 37 provided between the first pipe line 15 and the oil tank 31 is provided with a flow rate control valve 38 and a lowering valve 39 interlocking with the switching valve 34 from the upstream side. The fourth pipe 18 is connected to the oil tank 31 via a switching valve 34.
[0009]
Next, the operation of the tuning device 4 configured as described above will be described. First, when the pump 33 is driven at the time of ascent, the pressure oil is supplied from the first pipe line 15 to the first pressure oil chamber 10 via the switching valve 34 and the check valve 35 at the position shown in FIG. Push forward. Thereby, since the volume of the second pressure oil chamber 11 and the third pressure oil chamber 12 is reduced, the hydraulic oil in the second pressure oil chamber 11 flows from the inlet / outlet port 11a to the second conduit 16 and is sent to the hydraulic cylinder 3a, Similarly, the hydraulic oil in the third pressure oil chamber 12 flows from the inlet / outlet 12a to the third pipe 17 and is sent to the hydraulic cylinder 3b. Here, since the cross-sectional areas of the second pressure oil chamber 11 and the third pressure oil chamber 12 are the same, the hydraulic cylinders 3a and 3b having the same oil amount operate in synchronism, and the lifters 1a and 1b rise in the same movement. To do.
On the other hand, at the time of lowering, the switching valve 34 and the lowering valve 39 are simultaneously switched to the lowering side, so that the pressure oil is supplied from the fourth pipe 18 to the fourth pressure oil chamber 13 through the pressure oil path 19 in the fixed plunger 14. Therefore, the force of the cross-sectional area of the pressure oil passage 19 x the hydraulic pressure acts on the plunger 9. The hydraulic pressure applied to the hydraulic cylinders 3a, 3b by the load is also the piston 8 and the plunger from the second pipe 16 through the second pressure oil chamber 11 and from the third pipe 17 through the third pressure oil chamber 12, respectively. Therefore, the piston 8 is moved backward by the resultant force. Further, the hydraulic oil in the first pressure oil chamber 10 returns to the oil tank 31 from the first pipe 15 through the return pipe 37 by switching the lowering valve 39, and at this time, the flow control valve 38 flows through the return pipe 37. Since the amount of oil is made constant, the lowering speed of both lifters 1a and 1b does not change even if the load applied to both lifters 1a and 1b varies. Of course, even if the load applied to both lifters 1a and 1b is zero, the descending speed is not slowed by the pressure oil sent from the pressure oil passage 19 to the fourth pressure oil chamber 13.
Incidentally, at the time of initial setting, that is, when the lifters 1a and 1b are operated for the first time, since the air is contained in the second pressure oil chamber 11 and the third pressure oil chamber 12, first, no vehicle or the like is placed on the lifters 1a and 1b. Perform ascending operation with. Then, the plunger 9 reaches the most advanced position, and the third and fourth correction valves 22 and 23 are opened, so that the pressure oil from the pump 33 is supplied from the fourth correction valve 23 via the correction pipe 26. It is sent to the pressure oil chamber 12 and then sent from the third pipe 17 to the hydraulic cylinder 3b to raise the lifter 1b. At the same time, the pressure oil in the third pressure oil chamber 12 is sent to the second pressure oil chamber 11 and the hydraulic cylinder 3a through the third correction valve 22, the correction pipe line 24, and the second pipe line 16 to raise the lifter 1a. . Here, if the air is lifted and lowered while the air vent valves 29 and 29 are being vented several times, the air in the second and third pressure oil chambers 11 and 12 is completely vented and the hydraulic oil is filled. Note that the air in the fourth pressure oil chamber 13 is sent from the pressure oil passage 19 to the oil tank 31 through the fourth pipe 18 and the switching valve 34 at the time of ascent and is released to the atmosphere. Air bleeding will be completed.
[0010]
As described above, in the tuning device 4, the backward movement mechanism such as the fourth pressure oil chamber 13 and the fixed plunger 14 is employed for the plunger 9 of the synchronization cylinder 5, so that the downward movement of the hydraulic cylinders 3 a and 3 b Regardless of the presence or absence of the load and the magnitude of the load, it can be reliably performed at a constant speed. Of course, even if the viscosity of the oil increases at a low temperature, the descending speed is not affected. In addition, since the same mechanism is built into the synchronize cylinder 5 without using an external cylinder, etc., (1) the size and weight of the synchronize cylinder 5 can be reduced, the cost increase is suppressed, and the occurrence of failure is reduced. High reliability. (2) The layout of the hydraulic unit can be easily laid out and the entire circuit can be reduced in size without being restricted by the installation direction and position. (3) Since there is no portion that comes into contact with the outside air, there is an effect that dust and air are not mixed, and that reliable operation and improvement in durability can be expected.
In particular, according to the present embodiment, the size relationship described above, i.e. the cross-sectional area of the first oil chamber A O> cross-sectional area A 2 of the second cross-sectional area of the oil chamber A 1 + third oil chamber, the Due to the relationship that the cross-sectional area A 1 of the second pressure oil chamber = the cross-sectional area A 2 of the third pressure oil chamber, the first and second pressure oil chambers 11 and 12 have the primary oil pressure applied to the first pressure oil chamber 10. The thrust generated in each of the hydraulic cylinders 3a and 3b becomes stronger because the generated secondary hydraulic pressure becomes higher (pressure increasing effect). In other words, the hydraulic cylinders 3a and 3b of the present embodiment can be formed to be thinner when compared with those that obtain the same thrust, and as a result, a further lower floor of the lifters 1a and 1b can be achieved.
Further, according to the dimensional relationship as described above, the area ratio between the pressure oil chambers is large, and the hydraulic pressures of the second and third pipes 11 and 12 and the first pressure oil chamber 10 when lowered are kept low. The compression repulsion of the pressure oil when the lowering operation is stopped on the way is reduced, and the effect of reducing the jumping shock of the lifters 1a and 1b can be obtained. On the other hand, the X-type expansion / contraction mechanisms 2a and 2b are usually provided with a safety device for lowering the rack and the locking claw, but if the lowering operation is performed with the locking claw and the rack locked, Since extra force is not applied, it is not necessary to give extra strength to the lifter side. Therefore, an increase in cost can be prevented and the floor of the lifter can be lowered.
[0011]
Further, the characteristic correction action in this embodiment will be described below for each case.
Correction 1 (When both or one of the second and third pressure oil chambers 11 and 12 are reduced and the lifters 1a and 1b have insufficient heads or steps)
First, when correcting at the upper limit, when the lifter 1a, 1b is lifted to move the plunger 9 to the foremost position, the plunger 9 comes into contact with the third and fourth correction valves 22, 23, and both corrections are made. Open the valve. If the ascending operation is continued as it is, the pressure oil is not sent to the first pressure oil chamber 10 which is full, but is sent to the third pressure oil chamber 12 via the correction pipe line 26 and the fourth correction valve 23. The pressure oil in the third pressure oil chamber 12 is sent from the inlet / outlet 12a and the third pipe 17 to the hydraulic cylinder 3b, from the third correction valve 22 to the correction pipe 24, and from the second pipe 16 to the hydraulic cylinder 3a. Is also sent. Therefore, even if the plunger 9 stops, both the hydraulic cylinders 3a and 3b are operated until the stroke end, the pressure oil is full, and the step between the lifters 1a and 1b is corrected.
Correction 2
In the same case as the correction 1, in the case of correcting at the lower limit, when the lowering operation is performed and the plunger 9 is moved to the last retracted position, the piston 8 comes into contact with the first and second correction valves 20 and 21, and both correction valves Open the valve. If the lowering operation is continued as it is, the lifters 1a and 1b and the hydraulic cylinders 3a and 3b reach the lower limits, respectively, and the hydraulic oil does not return from the hydraulic cylinders 3a and 3b. , 12 are in a vacuum state. At this time, since the lowering valve 39 is also opened, the hydraulic oil in the oil tank 31 enters the first pressure oil chamber 10 from the return pipe 37 through the first pipe line 15 and further from the first correction valve 20 to the correction pipe. It is sent into the second pressure oil chamber 11 through the passage 24 and the second pipeline 16 by atmospheric pressure. Similarly, the hydraulic oil that has entered the first pressure oil chamber 10 is also sent to the third pressure oil chamber 12 by atmospheric pressure via the second correction valve 21, the correction pipeline 25, and the inlet / outlet 12b. Therefore, both the second and third pressure oil chambers 11 and 12 are filled with hydraulic oil, and the steps of the lifters 1a and 1b are corrected.
[0012]
Correction 3 (When the pressure oil in one or both of the second and third pressure oil chambers 11 and 12 increases and a step or a lower limit is not reached in the lifters 1a and 1b)
First, when correcting at the upper limit, the ascending operation is performed and either lifter 1a or 1b is operated until the upper limit is reached. At this time, the plunger 9 does not reach the most advanced position. Here, when the lifter 1 b reaches the upper limit first, the hydraulic pressure in the third pressure oil chamber 12 increases to about twice the maximum hydraulic pressure generated by the pump 33. Then, the third correction valve 22 functions as a relief valve, opens and feeds pressure oil from the correction pipe 24 and the second pipe 16 to the hydraulic cylinder 3a on the lifter 1a side, and raises the lifter 1a to the upper limit. At the same time, the safety valve 28 connected to the third pipeline 17 is also operated to reduce the hydraulic pressure in the pipeline 17. Therefore, the pressure balance between the second and third pressure oil chambers 11 and 12 is achieved, the occurrence of abnormally high pressure is prevented, and the step is also corrected. Thereafter, the pressure oil from the pump 33 stops circulating between the pressure oil supply pipe 32, the return pipe 37, and the oil tank 31.
On the other hand, when the lifter 1a reaches the upper limit first, the hydraulic pressure on the lifter 1a side becomes an abnormally high pressure due to the pressure increasing effect as described above. In this case, the safety valve 28 connected to the second pipe line 16 causes the abnormally high pressure. Is opened, and it is possible to prevent damage to the apparatus and correct the level difference.
Correction 4
In the same case as the correction 3, when correcting at the lower limit, the lowering operation is first performed to move the plunger 9 to the last retracted position. At this time, the lifters 1a and 1b do not reach the lower limit position. However, since the piston 8 opens the first and second correction valves 20 and 21, the hydraulic oil generated in the hydraulic cylinders 3a and 3b by the dead weight of the lifters 1a and 1b causes the hydraulic oil in the hydraulic cylinder 3a to flow into the second pipe. The oil is discharged from the return pipe 37 to the oil tank 31 through the passage 16, the correction pipe 24, the first correction valve 20, the first pressure oil chamber 10, and the first pipe 15. Similarly, the hydraulic oil in the hydraulic cylinder 3b passes through the third pipe 17, the third pressure oil chamber 12, the correction pipe 25, the second correction valve 21, the first pressure oil chamber 10, and the first pipe 15. The oil is discharged from the return pipe 37 to the oil tank 31. Therefore, both lifters 1a and 1b can be lowered to the lower limit, and the level difference is eliminated.
[0013]
As described above, according to the present embodiment, the steps of the lifters 1a and 1b can be corrected and the upper and lower limits can not be reached regardless of the upper and lower limit positions of the lifters 1a and 1b. In particular, since the correction is performed only by a simple ascending or descending operation, the user can automatically eliminate the step while using the lifter without performing a special operation for correction. Good usability can be obtained.
The step between the lifters may be caused by the amount of oil in the pressure oil chamber as in the case described above, and may also occur when the lift platform hits an obstacle while the lifter is lowered and only one of the lifts is prevented from descending. . However, in this embodiment, the differential pressure between the hydraulic cylinders appears more easily than the conventional method of applying a hydraulic pressure to the opposite side of the hydraulic cylinder and forcibly lowering it. If a sensor that detects this differential pressure is incorporated, Can be easily detected, and even in this case, it is possible to prevent the occurrence of a step.
[0014]
In the above-described embodiment, a configuration in which a plunger provided with one piston is used, a pressure oil chamber is provided in front of the piston and in front of the plunger, and two connected hydraulic cylinders are synchronized with each other has been described. However, by arranging a plurality of the above-mentioned pistons in the axial direction to form pressure oil chambers having the same cross-sectional area between the pistons, and connecting these pressure oil chambers to a hydraulic cylinder, respectively, Even in the form of synchronizing the cylinders, it is possible to employ a backward movement mechanism such as a fixed plunger as described above.
[0015]
【The invention's effect】
According to the first aspect of the present invention, since the return mechanism is built in the synchronization cylinder, the lowering operation of the hydraulic cylinder can be reliably performed at a constant speed regardless of the presence or absence of the load and the magnitude of the load. Of course, even if the viscosity of the oil increases at a low temperature, the descending speed is not affected. In addition, the size and weight of the synchronizing cylinder can be reduced, the cost can be suppressed, and the occurrence of failure can be reduced and high reliability can be obtained. Furthermore, the hydraulic unit can be easily laid out without being restricted by the installation direction and position setting, and the entire circuit can be reduced in size. In addition, since there is no portion that comes into contact with the outside air, there is no contamination of dust or air, and reliable operation and improved durability can be expected. In particular, the use of the return pressure oil chamber and the fixed plunger makes it possible to easily configure the return mechanism, leading to further suppression of cost increase.
According to the second aspect of the present invention, in addition to the effect of the first aspect, the use of the correction pipe line causes the oil amount between the pressure oil chambers to be different due to oil leakage, etc. Even if the stroke end is not reached, this can be effectively corrected to maintain an appropriate reciprocating operation of the hydraulic cylinder. In particular, since this correction is performed at a predetermined reciprocating position of the plunger, it is automatically corrected by normal use of the hydraulic cylinder without requiring a special operation for correction, and the usability is improved. .
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory diagram of a hydraulic cylinder tuning device provided in an automobile maintenance lift.
[Explanation of symbols]
1a, 1b ... Lifter, 2a, 2b ... X-type telescopic mechanism, 3a, 3b ... Hydraulic cylinder, 4 ... Tuning device, 5 ... Synchronizing cylinder, 7 ... Cylinder tube, 8 ... Piston, 9 ... · Plunger, 10 · · First pressure oil chamber, 11 · · Second pressure oil chamber, 12 · · Third pressure oil chamber, 13 · · Fourth pressure oil chamber, 14 · · Fixed plunger, 15 · · 1 Pipe, 16, ... Second pipe, 17 .... Third pipe, 18 .... Fourth pipe, 20 .... First compensation valve, 21 ... Second compensation valve, 22 .... Third compensation valve , 23 ··· Fourth correction valve, 30 · · Hydraulic unit, 31 · · oil tank, 33 · · pump, 34 · · switching valve.

Claims (2)

少なくとも１つのピストン部を備え、油圧源からの圧油の供給によって往動するプランジャを内蔵すると共に、前記ピストン部及びプランジャの往動側に夫々圧油室を形成し、この各圧油室に夫々油圧シリンダを接続して、前記プランジャの往動により、前記各圧油室から夫々接続される前記各油圧シリンダへ等量の圧油を供給可能なシンクロナイズシリンダを設けた油圧シリンダの同調装置であって、
前記シンクロナイズシリンダに、前記プランジャ内部に形成された復動用圧油室と、前記プランジャ往動側の圧油室内にあって前記油圧源に接続される油路を内設して復動側へ突設され、前記プランジャに同軸で挿通して前記油路を前記復動用圧油室と連通させた固定プランジャとからなる復動機構を内設し、前記油圧源から前記固定プランジャへの圧油の供給により前記プランジャに復動方向への油圧を付与可能としたことを特徴とする油圧シリンダの同調装置。At least one piston part is provided, and a plunger that moves forward by supply of pressure oil from a hydraulic power source is built in, and a pressure oil chamber is formed on each of the piston part and the forward movement side of the plunger, A hydraulic cylinder tuning apparatus provided with a synchronized cylinder, each connected to a hydraulic cylinder, and capable of supplying an equal amount of pressure oil from each pressure oil chamber to each of the hydraulic cylinders connected by the forward movement of the plunger. There,
The synchronizing cylinder is provided with a return pressure oil chamber formed inside the plunger and an oil passage in the pressure oil chamber on the plunger forward side and connected to the hydraulic power source so as to protrude toward the return side. A return movement mechanism comprising a fixed plunger that is coaxially inserted into the plunger and communicates the oil passage with the pressure oil chamber for return movement, so that pressure oil from the hydraulic power source to the fixed plunger is provided. A hydraulic cylinder tuning apparatus characterized in that a hydraulic pressure in a backward movement direction can be applied to the plunger by supply . 前記シンクロナイズシリンダに、前記プランジャの所定の往復動位置で前記各圧油室同士を連通させ、各圧油室の油量を適性量に補正して均等化させる補正管路を設けた請求項１に記載の油圧シリンダの同調装置。 2. The correction cylinder is provided with a correction pipe that communicates the pressure oil chambers at a predetermined reciprocating position of the plunger and corrects the oil amount of each pressure oil chamber to an appropriate amount to equalize. A hydraulic cylinder tuning device according to claim 1.
JP03063297A 1997-02-14 1997-02-14 Hydraulic cylinder tuning device Expired - Fee Related JP3764236B2 (en)

Priority Applications (3)

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JP03063297A JP3764236B2 (en) 1997-02-14 1997-02-14 Hydraulic cylinder tuning device
TW086206534U TW360231U (en) 1997-02-14 1997-04-24 Synchronization apparatus for oil cylinder
KR1019970017197A KR100231069B1 (en) 1997-02-14 1997-05-06 Synchronizing apparatus for hydraulic cylinder

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Cited By (2)

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Publication number Priority date Publication date Assignee Title
CN104003326A (en) * 2013-05-22 2014-08-27 芜湖高昌液压机电技术有限公司 Series synchronization of hydraulic oil cylinder of automobile lifter
EP3207261A4 (en) * 2014-10-17 2018-10-17 Vehicle Service Group, LLC Hydraulic synchronizer

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3877105B2 (en) * 1998-09-22 2007-02-07 株式会社スギヤス Hydraulic tuning device and hydraulic lift
JP4733254B2 (en) * 2000-10-23 2011-07-27 株式会社ヤスヰ Hydraulic circuit for lift for vehicle maintenance
KR101416566B1 (en) * 2014-01-02 2014-07-18 (주)남광유압 Synchronous device in hydraulic cylinder
CN109458369B (en) * 2018-12-29 2023-10-27 浙江大学舟山海洋研究中心 Three-cylinder synchronous lifting mechanism

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Publication number Priority date Publication date Assignee Title
JPS61127904A (en) * 1984-11-28 1986-06-16 Hitachi Ltd Hydraulic circuit for synchronous cylinder

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104003326A (en) * 2013-05-22 2014-08-27 芜湖高昌液压机电技术有限公司 Series synchronization of hydraulic oil cylinder of automobile lifter
EP3207261A4 (en) * 2014-10-17 2018-10-17 Vehicle Service Group, LLC Hydraulic synchronizer
EP3744675A1 (en) * 2014-10-17 2020-12-02 Vehicle Service Group, LLC Hydraulic synchronizer
US10988358B2 (en) 2014-10-17 2021-04-27 Vehicle Service Group, Llc Hydraulic synchronizer

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