JPH0714202U - Vibration suppressor for work equipment - Google Patents
Vibration suppressor for work equipmentInfo
- Publication number
- JPH0714202U JPH0714202U JP4827193U JP4827193U JPH0714202U JP H0714202 U JPH0714202 U JP H0714202U JP 4827193 U JP4827193 U JP 4827193U JP 4827193 U JP4827193 U JP 4827193U JP H0714202 U JPH0714202 U JP H0714202U
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- JP
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- Prior art keywords
- valve
- circuit
- hydraulic
- opening
- pilot
- 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.)
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- Operation Control Of Excavators (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
(57)【要約】
【目的】 油圧ショベルのブーム昇降停止時に発生する
振動を抑制するとともに、振動抑制動作を任意に選択で
きるようにする。
【構成】 ブームシリンダ５のボトム回路１４とヘッド
回路１６との連通回路３０に、電磁切換弁３２、絞り弁
３３、パイロット油圧で回路を開く第１開閉弁３４、回
路を閉じる第２開閉弁３５を介装し、第１開閉弁３４の
パイロット油圧回路４３に絞り弁４４を設ける。方向制
御弁１１を操作してブームシリンダ５を縮め、ブームを
下げて停止すると作業機の慣性によりボトム室１５に高
圧が発生する。方向制御弁１１操作中は第１開閉弁３４
は開き、第２開閉弁３５は閉じている。ブーム下げ操作
を停止すると第２開閉弁３５は開き、第１開閉弁は絞り
弁４４の働きでやや遅れて閉じる。その間連通回路３０
は連通しており、ボトム室１５の油はヘッド室１７に逃
げ、ピーク圧を下げて振動を抑制する。オペレータは電
磁切換弁３２を操作して振動抑制回路のＯＮ−ＯＦＦを
任意に選択できる。
(57) [Summary] [Purpose] To suppress the vibration generated when the boom of the hydraulic excavator stops moving up and down, and to enable the vibration suppression operation to be selected arbitrarily. [Composition] In a communication circuit 30 between the bottom circuit 14 of the boom cylinder 5 and the head circuit 16, an electromagnetic switching valve 32, a throttle valve 33, a first opening / closing valve 34 for opening the circuit with pilot hydraulic pressure, and a second opening / closing valve 35 for closing the circuit. The throttle valve 44 is provided in the pilot hydraulic circuit 43 of the first opening / closing valve 34. When the directional control valve 11 is operated to contract the boom cylinder 5 and lower the boom to stop, a high pressure is generated in the bottom chamber 15 due to the inertia of the work machine. During operation of the direction control valve 11, the first opening / closing valve 34
Is open and the second on-off valve 35 is closed. When the boom lowering operation is stopped, the second opening / closing valve 35 is opened, and the first opening / closing valve is closed by the action of the throttle valve 44 with a slight delay. Meanwhile, the communication circuit 30
Are communicating with each other, and the oil in the bottom chamber 15 escapes to the head chamber 17 to reduce the peak pressure and suppress the vibration. The operator can operate the electromagnetic switching valve 32 to arbitrarily select ON-OFF of the vibration suppressing circuit.
Description
【０００１】[0001]
本考案は、建設機械、特には油圧ショベルや油圧クレーン等の、作業機停止時 に発生するショックを軽減する作業機の振動抑制装置に関する。 The present invention relates to a vibration suppressing device for a construction machine, particularly a work machine such as a hydraulic excavator or a hydraulic crane, which reduces a shock generated when the work machine is stopped.
【０００２】[0002]
図４は油圧ショベルの側面図であり、下部走行体１に装着された上部旋回体２ には作業機３のブーム４が揺動自在に装着されている。上部旋回体２とブーム４ とはブームシリンダ５により連結されており、ブームシリンダ５の伸縮によりブ ーム４は昇降する。６はアーム、７はバケットである。 FIG. 4 is a side view of the hydraulic excavator. The boom 4 of the working machine 3 is swingably mounted on the upper swing body 2 mounted on the lower traveling body 1. The upper swing body 2 and the boom 4 are connected by a boom cylinder 5, and the boom 4 moves up and down as the boom cylinder 5 expands and contracts. 6 is an arm and 7 is a bucket.
【０００３】 図５は従来の油圧ショベルのブームシリンダ駆動油圧回路図であり、１０は作 業機用の油圧ポンプ、２０はパイロット回路用油圧ポンプ、１１はブームシリン ダ５への圧油を制御する方向制御弁、１２は方向制御弁１１の上げ側パイロット ポート、１３は下げ側パイロットポートである。１４はブームシリンダ５のボト ム側油室１５と方向制御弁１１とを接続するボトム回路、１６はブームシリンダ ５のヘッド側油室１７と方向制御弁１１とを接続するヘッド回路である。 ２１は方向制御弁１１を制御するパイロット油圧操作弁、２２は操作レバーで あり、２３はパイロット油圧操作弁２１と上げ側パイロットポート１２とを接続 するパイロット油圧回路、２４はパイロット油圧操作弁２１と下げ側パイロット ポート１３とを接続するパイロット油圧回路である。２５はパイロット油圧操作 弁２１とオイルタンク１８とを接続するドレン回路であり、操作レバー２２が中 立Ｎ位置のときにはパイロット油圧回路２３、２４はドレン回路２５に連通して いる。FIG. 5 is a boom cylinder drive hydraulic circuit diagram of a conventional hydraulic excavator. 10 is a hydraulic pump for an operating machine, 20 is a hydraulic pump for a pilot circuit, 11 is a hydraulic oil for controlling the boom cylinder 5. Is a rising side pilot port of the directional control valve 11, and 13 is a lowering side pilot port. Reference numeral 14 is a bottom circuit connecting the bottom side oil chamber 15 of the boom cylinder 5 and the direction control valve 11, and 16 is a head circuit connecting the head side oil chamber 17 of the boom cylinder 5 and the direction control valve 11. Reference numeral 21 is a pilot hydraulic operating valve for controlling the directional control valve 11, 22 is an operating lever, 23 is a pilot hydraulic circuit connecting the pilot hydraulic operating valve 21 and the raising pilot port 12, and 24 is a pilot hydraulic operating valve 21. It is a pilot hydraulic circuit that connects the lower pilot port 13. A drain circuit 25 connects the pilot hydraulic operation valve 21 and the oil tank 18. The pilot hydraulic circuits 23 and 24 communicate with the drain circuit 25 when the operation lever 22 is in the neutral N position.
【０００４】 次に作動について説明する。中立Ｎ位置にある操作レバー２２を上げＵ側に操 作すると、パイロット油圧ポンプ２０からの圧油はパイロット油圧回路２３を経 て上げ側パイロットポート１２に至り、方向制御弁１１を右側に移動させる。方 向制御弁１１はＵ位置となって油圧ポンプ１０の圧油はボトム回路１４を経てブ ームシリンダ５のボトム側油室１５に供給され、ブームシリンダ５は伸びてブー ム４を上昇させる。操作レバー２２をＮ位置に戻すとパイロット油圧回路２３、 ２４の油圧はオイルタンク１８の圧力に低下し、方向制御弁１１はばねの力によ りＮ位置となり、ブームシリンダポートとオイルタンクポートとは遮断されてブ ームシリンダ５の伸びは終了し、ブーム４は停止する。 操作レバー２２を下げＤ側に操作するとパイロット油圧はパイロット油圧回路 ２４を経て下げ側パイロットポート１３に至り、方向制御弁１１をＤ位置に移動 させ、圧油はヘッド回路１６を経てブームシリンダ５のヘッド側油室１７に供給 され、ブームシリンダ５は縮んでブーム４を下降させる。操作レバー２２をＮ位 置に戻すとブーム４は停止する。Next, the operation will be described. When the operating lever 22 at the neutral N position is raised and operated to the U side, the pressure oil from the pilot hydraulic pump 20 reaches the raising pilot port 12 via the pilot hydraulic circuit 23 and moves the directional control valve 11 to the right. . The direction control valve 11 is in the U position, and the pressure oil of the hydraulic pump 10 is supplied to the bottom side oil chamber 15 of the boom cylinder 5 via the bottom circuit 14, and the boom cylinder 5 extends to raise the boom 4. When the operating lever 22 is returned to the N position, the hydraulic pressure of the pilot hydraulic circuits 23 and 24 drops to the pressure of the oil tank 18, and the directional control valve 11 is moved to the N position by the force of the spring, so that the boom cylinder port and the oil tank port are not connected. Is interrupted, the boom cylinder 5 finishes extending, and the boom 4 stops. When the operating lever 22 is lowered and operated to the D side, the pilot oil pressure reaches the lower pilot port 13 via the pilot oil pressure circuit 24, moves the directional control valve 11 to the D position, and the pressure oil passes through the head circuit 16 and the boom cylinder 5 moves. It is supplied to the head side oil chamber 17, and the boom cylinder 5 contracts to lower the boom 4. The boom 4 stops when the operating lever 22 is returned to the N position.
【０００５】 上記のブーム下げの作動を図３のタイムチャートにより説明する。（ａ）は操 作レバー２１変位、（ｂ）は方向制御弁１１変位、（ｃ）はブームシリンダボト ム側油室１５の圧力、（ｄ）はブームシリンダヘッド側油室１７の圧力の時間に 対する変化をそれぞれ示している。 いま、（ａ）に示すように操作レバー２１を中立Ｎ位置から下げＤ位置に、時 刻ｔ0 で操作開始し、ｔ1 でフルストローク動かすと、パイロット油圧は方向切 換弁１１に供給され、（ｂ）に示すようにｔ2 で移動開始しｔ3 で最大変位とな る。ｔ2 −ｔ0 は応答遅れであり、管路内の作動油の圧縮性、粘度、および圧力 損失、回路に用いられるゴムホースの弾性等により生ずる。 圧油はｔ2 でブームシリンダ５のヘッド側油室１７に流入し、ブーム４は下降 を開始し、（ｄ）に示すようにブームシリンダ５のヘッド側圧力はｔ3 で最大と なる。（ａ）に示すように時刻ｔ4 で操作レバー１４をＤ位置からＮ位置に操作 開始し、ｔ6 で操作を終了すると（ｂ）に示すようにｔ5 で方向切換弁１１は移 動を開始し、ｔ7 で終了する。方向制御弁１１の戻り速度は両端に設けられたば ねの力と、パイロット油圧回路２３、２４およびパイロット油圧操作弁２１の内 部に生ずる圧力損失、油の粘度等で決まる。この時点でブーム４は下降停止とな る。The operation of lowering the boom will be described with reference to the time chart of FIG. (A) is the displacement of the operating lever 21, (b) is the displacement of the directional control valve 11, (c) is the pressure in the boom cylinder bottom side oil chamber 15, and (d) is the time in the boom cylinder head side oil chamber 17. The changes for the Now, as shown in (a), when the operation lever 21 is lowered from the neutral N position to the D position, operation is started at time t 0 , and a full stroke is moved at t 1 , pilot hydraulic pressure is supplied to the direction switching valve 11, As shown in (b), movement starts at t 2 and reaches maximum displacement at t 3 . t 2 -t 0 is the response delay, the compressibility of the hydraulic fluid in the conduit, viscosity, and pressure loss, caused by the elastic like rubber hoses used in the circuit. The pressure oil flows into the head side oil chamber 17 of the boom cylinder 5 at t 2 , the boom 4 starts to descend, and the head side pressure of the boom cylinder 5 becomes maximum at t 3 as shown in (d). As shown in (a), the operation lever 14 is started from the D position to the N position at time t 4 , and when the operation is finished at t 6 , the directional control valve 11 is moved at t 5 as shown in (b). It starts and ends at t 7 . The return speed of the directional control valve 11 is determined by the force of the springs provided at both ends, the pressure loss generated inside the pilot hydraulic circuits 23, 24 and the pilot hydraulic operation valve 21, the viscosity of the oil, and the like. At this point, the boom 4 stops descending.
【０００６】[0006]
前述のごとく、方向切換弁をＤ位置からＮ位置に戻し始めるとブーム４は下降 停止しはじめ、図３（ｃ）に示すように方向制御弁１１の操作終了時にブームシ リンダ５のボトム圧は急激に上昇し、ｔ7 においてピーク圧Ｐ1 を示す。これは 作業機３の慣性が大きいためである。 ｔ7 でブーム４の下降は停止し、次にはボトム側の圧力の反力でブームは上昇 し、作業機の慣性でブームシリンダのヘッド側の圧力が上昇し、（ｄ）に示すよ うにｔ8 でヘッド側のピーク圧はＰ2 となりブームの上昇は止まる。以後はこの ようにブームシリンダのボトム圧とヘッド圧とが交互に上昇、下降を繰り返し、 ブームシリンダが伸縮して作業機は上下に揺動（振動）を繰り返し、次第に減衰 するが、この振動は図３の（ｃ）、（ｄ）に示すように相当長く継続する。 この現象は作業機の下げ動作停止時のみならず、上げ動作停止時にも同様に発 生する。 この作業機の振動は油圧ショベル本体をも揺らすこととなり、作業機の作動停 止の都度、オペレータは不快感を覚え、疲労の増大を招く。 また、図４に示すように、バケットに土砂等を積み込んでいると振動により積 み荷がこぼれ落ちることがあり、安全性、生産性の上からも問題となっている。 そのため、この振動を抑制させたいわけであるが、振動を抑制すると動作が緩 慢になるのが一般的である。しかしながら、油圧ショベルの作業では、たとえば バケット７の底面を打ちつけて地面を締め固める転圧作業のように短時間のうち に作業機３の上げ下げを繰り返す必要のある作業もあり、以上の相反する要求を 同時に解決する方策が求められている。 また、振動抑制方策を採用した場合、低温時に油の粘度が大きくなり、極端な 作動遅れを生ずる危険性もある。As described above, when the directional control valve starts returning from the D position to the N position, the boom 4 begins to descend and stop, and the bottom pressure of the boom cylinder 5 suddenly increases at the end of the operation of the directional control valve 11 as shown in FIG. 3 (c). , And shows a peak pressure P 1 at t 7 . This is because the work machine 3 has a large inertia. At t 7 , the boom 4 stops descending, then the boom rises due to the reaction force of the pressure on the bottom side, the pressure on the head side of the boom cylinder rises due to the inertia of the work machine, and as shown in (d). At t 8 , the peak pressure on the head side becomes P 2 and the boom stops rising. After that, the bottom pressure and the head pressure of the boom cylinder alternately rise and fall repeatedly in this way, the boom cylinder expands and contracts, the work machine repeatedly swings up and down (vibrates), and is gradually damped. As shown in (c) and (d) of FIG. This phenomenon occurs not only when the lowering operation of the work implement is stopped, but also when the raising operation is stopped. This vibration of the working machine also rocks the main body of the hydraulic excavator, and every time the working machine is stopped, the operator feels uncomfortable and increases fatigue. Further, as shown in FIG. 4, when soil or the like is loaded in the bucket, the load may spill due to vibration, which is a problem from the viewpoint of safety and productivity. Therefore, it is desirable to suppress this vibration, but if the vibration is suppressed, the operation generally becomes slow. However, in the work of the hydraulic excavator, there is a work in which it is necessary to repeatedly raise and lower the work implement 3 within a short period of time, such as a compaction work in which the bottom surface of the bucket 7 is struck and the ground is compacted. There is a need for a solution that simultaneously solves Also, if vibration suppression measures are adopted, the viscosity of the oil will increase at low temperatures, and there is the danger of an extreme delay in operation.
【０００７】 上記作業機の振動抑制のためには、特願平３−３５１３５０あるいは特開平４ −３４３９２５により提案がなされているが、前者はマイコンを必要とするため 高価であり、普及している油圧パイロット式油圧ショベルには採用困難という問 題があり、後者においては制御バルブ数が多く高価であるという問題がある。[0007] Japanese Patent Application No. 3-351350 or Japanese Patent Application Laid-Open No. 4-343925 proposes to suppress the vibration of the working machine, but the former requires a microcomputer and is therefore expensive and is widely used. The hydraulic pilot hydraulic excavator has a problem that it is difficult to adopt, and the latter has a problem that the number of control valves is large and it is expensive.
【０００８】 本考案は上記の問題点に着目してなされたもので、作業機の上昇、下降の動作 停止時に発生する振動を抑制するとともに、必要に応じて例えば、短時間のうち に作業機の上げ下げを繰り返す必要がある場合には、運転者の意志で振動抑制装 置をＯＦＦにする事が可能で、かつ、油温が低く油の粘度が大きく、作動おくれ が大きくなりすぎる場合には、強制的に振動抑制装置をＯＦＦにする事が可能な 振動抑制装置を経済的に提供することを目的としている。The present invention has been made in view of the above problems, and suppresses the vibration generated when the operation of the working machine is stopped from rising and lowering, and if necessary, for example, in a short time. If it is necessary to repeatedly raise and lower the oil pressure, it is possible for the driver to turn off the vibration suppression device, and if the oil temperature is low and the oil viscosity is high and the operation delay is too large, The purpose is to economically provide a vibration suppression device that can forcibly turn off the vibration suppression device.
【０００９】[0009]
上記の目的達成のため、本考案に係る作業機の振動抑制装置の第１の考案にお いては、本体に揺動自在に装着された作業機を昇降自在に支持する油圧シリンダ と、油圧源から該油圧シリンダに供給する圧油を制御するパイロット油圧式方向 制御弁と、該方向制御弁を制御するパイロット油圧操作弁とを備えた建設機械の 油圧回路において、前記油圧シリンダのヘッド側とボトム側とを連通する連通回 路を設け、前記連通回路上に絞り弁と、前記連通回路を開閉する切換弁と、パイ ロット油圧式の第１開閉弁と、第２開閉弁とを直列に介装することを特徴として おり、第２の考案においては、前記パイロット油圧操作弁のパイロット油圧回路 と、パイロット油圧を受けて前記連通回路を開く前記第１開閉弁のパイロットポ ートと、パイロット油圧を受けて前記連通回路を閉じる第２開閉弁のパイロット ポートとを、高圧側の油を選択導入するシャトルバルブを介して接続し、前記パ イロット油圧回路と前記第１開閉弁のパイロットポートとを連通する回路上に絞 り弁を介装することを特徴としており、第３の考案においては、本体に揺動自在 に装着された作業機を昇降自在に支持する油圧シリンタと、油圧源から該油圧シ リンダに供給する圧油を制御するパイロット油圧式方向制御弁と、前記方向制御 弁を制御するパイロット油圧操作弁とを備えた建設機械の油圧回路において、前 記油圧シリンダのヘッド側とボトム側とを連通する連通回路を設け、前記連通回 路上に絞り弁と、前記連通回路を開閉する電磁切換弁と、パイロット油圧式の第 １開閉弁および第２開閉弁とを直列に介装し、前記電磁切換弁に接続する電気回 路上にＯＮ−ＯＦＦスイッチと、予め定められた油温に達すると信号を受けて前 記電気回路をカットする温度センサとを配設せることを特徴としている。 In order to achieve the above-mentioned object, in a first invention of a vibration suppressor for a working machine according to the present invention, a hydraulic cylinder for swingably supporting a working machine mounted on a main body and a hydraulic power source are provided. In a hydraulic circuit of a construction machine equipped with a pilot hydraulic type directional control valve for controlling pressure oil supplied from the hydraulic cylinder to the hydraulic cylinder, and a pilot hydraulic operating valve for controlling the directional control valve, a head side and a bottom side of the hydraulic cylinder A communication circuit for communicating with the side is provided, and a throttle valve on the communication circuit, a switching valve for opening and closing the communication circuit, a pilot hydraulic first opening / closing valve, and a second opening / closing valve are connected in series. In the second invention, a pilot hydraulic circuit of the pilot hydraulic operation valve, a pilot port of the first opening / closing valve that receives the pilot hydraulic pressure and opens the communication circuit, and a pilot The pilot port of the second on-off valve that receives the hydraulic pressure and closes the communication circuit is connected via a shuttle valve that selectively introduces high-pressure oil, and the pilot hydraulic circuit and the pilot port of the first on-off valve are connected. The third invention is characterized in that a throttle valve is provided on a circuit communicating with the hydraulic cylinder and a hydraulic cylinder for supporting a working machine that is swingably mounted on the main body so that the working machine can move up and down. In a hydraulic circuit of a construction machine equipped with a pilot hydraulic type directional control valve for controlling pressure oil supplied from the hydraulic cylinder to the hydraulic cylinder, and a pilot hydraulic operating valve for controlling the directional control valve, the head side of the hydraulic cylinder described above. And a bottom side are provided with a communication circuit, and a throttle valve on the communication circuit, an electromagnetic switching valve that opens and closes the communication circuit, and a pilot hydraulic first opening / closing valve and a second opening / closing valve. An ON-OFF switch and a temperature sensor that cuts off the electric circuit upon receiving a signal when a predetermined oil temperature is reached are provided on an electric circuit connected in series and connected to the electromagnetic switching valve. It is characterized by that.
【００１０】[0010]
上記構成によれば、作業機を昇降させる油圧シリンダのヘッド側とボトム側と を連通する連通回路を設け、連通回路上に絞り弁と、連通回路を開閉する切換弁 と、パイロット油圧操作弁のパイロット油圧を受けて連通回路を開くパイロット 油圧式の第１開閉弁と、該パイロット油圧を受けて連通回路を閉じる第２開閉弁 とを設けた。そしてパイロット油圧操作弁のパイロット回路と、第１、第２開閉 弁のパイロットポートとを、高圧側の油を選択導入するシャトルバルブを介して 接続し、該パイロット回路と第１開閉弁とを接続する回路上に絞り弁を介装した 。 そのため、切換弁を開き、パイロット油圧操作弁を上げ、下げ、どちらかに操 作すると油圧シリンダは伸縮する。同時にシャトルバルブを介して圧油は第１開 閉弁を開き、第２開閉弁を閉じる。つぎに、パイロット油圧操作弁を中立にする と油圧シリンダは停止し、第１開閉弁は閉じ、第２開閉弁は開く。このとき、第 １と第２開閉弁は絞り弁の働きにより開閉時期にタイムラグを生じ、短時間両方 の開閉弁が開の状態となる。したがって、油圧シリンダのヘッド側とボトム側と はこの間、連通し、絞り弁を介して少量の油が高圧側から低圧側に流入し、ピー ク圧を低減する。 切換弁を閉じた場合には、従来の油圧装置と同一の回路となり従来と同様な働 きをする。 また、前記連通回路上に回路を開閉する電磁切換弁を介装し、その電気回路上 にＯＮ−ＯＦＦスイッチと油温により回路をカットする温度センサとを設けたた め、油が予め定められた温度に達すると電気回路がカットされ、ＯＮ−ＯＦＦス イッチを操作しても振動抑制装置が作動しないようになる。 According to the above configuration, a communication circuit that connects the head side and the bottom side of the hydraulic cylinder that raises and lowers the working machine is provided, and the throttle valve, the switching valve that opens and closes the communication circuit, and the pilot hydraulic operation valve are provided on the communication circuit. A pilot hydraulic type first opening / closing valve that receives the pilot oil pressure to open the communication circuit and a second opening / closing valve that receives the pilot oil pressure and closes the communication circuit are provided. Then, the pilot circuit of the pilot hydraulic operating valve and the pilot ports of the first and second opening / closing valves are connected via a shuttle valve that selectively introduces high-pressure side oil, and the pilot circuit and the first opening / closing valve are connected. A throttle valve was installed on the circuit. Therefore, open the switching valve, raise and lower the pilot hydraulic operation valve, and operate either way to expand or contract the hydraulic cylinder. At the same time, the pressure oil opens the first opening / closing valve and closes the second opening / closing valve via the shuttle valve. Next, when the pilot hydraulic operation valve is neutralized, the hydraulic cylinder is stopped, the first opening / closing valve is closed, and the second opening / closing valve is opened. At this time, there is a time lag in the opening and closing timing of the first and second on-off valves due to the action of the throttle valve, and both on-off valves are open for a short time. Therefore, the head side and the bottom side of the hydraulic cylinder communicate with each other during this period, and a small amount of oil flows from the high pressure side to the low pressure side via the throttle valve, reducing the peak pressure. When the switching valve is closed, the circuit becomes the same as the conventional hydraulic system and the same operation as the conventional one is performed. Further, since an electromagnetic switching valve for opening and closing the circuit is provided on the communication circuit, and an ON-OFF switch and a temperature sensor for cutting the circuit by the oil temperature are provided on the electric circuit, oil is predetermined. When the temperature reaches a certain temperature, the electric circuit is cut and the vibration suppressor does not operate even if the ON-OFF switch is operated.
【００１１】[0011]
以下に、本考案に係る作業機の振動抑制装置の実施例について、図面を参照し て詳述する。 図１は第１実施例のブームシリンダ駆動油圧回路図である。ブームシリンダ５ 、油圧ポンプ１０、方向制御弁１１、上げ側パイロットポート１２、下げ側パイ ロットポート１３、ボトム回路１４、ボトム側油室１５、ヘッド回路１６、ヘッ ド側油室１７、オイルタンク１８、パイロット油圧ポンプ２０、パイロット油圧 操作弁２１、操作レバー２２、パイロット油圧回路２３，２４、ドレン回路２５ の部品およびその働きは従来のものと同一なので説明は省略し、異なる部分につ いて説明する。 ブームシリンダ５のボトム回路１４とヘッド回路１６との間には連通回路３０ が設けられ、連通回路３０上にはＯＮ−ＯＦＦスイッチ３１を備えた電磁切換弁 ３２、絞り弁３３、パイロット油圧式の第１開閉弁３４、第２開閉弁３５が直列 に介装されている。パイロット油圧回路２３、２４を連通する回路４０には高圧 側の油を選択導入するシャトルバルブ４１が設けられ、回路４０と第２開閉弁３ ５のパイロットポート３７とはシャトルバルブ４１を介して回路４２により接続 されている。第１開閉弁３４のパイロットポート３６と回路４２とを接続する回 路４３上には絞り弁４４が配設されている。 Hereinafter, an embodiment of a vibration suppressing device for a working machine according to the present invention will be described in detail with reference to the drawings. FIG. 1 is a boom cylinder drive hydraulic circuit diagram of the first embodiment. Boom cylinder 5, hydraulic pump 10, directional control valve 11, raising pilot port 12, lower pilot port 13, bottom circuit 14, bottom oil chamber 15, head circuit 16, head oil chamber 17, oil tank 18 The parts of the pilot hydraulic pump 20, the pilot hydraulic operating valve 21, the operating lever 22, the pilot hydraulic circuits 23 and 24, and the drain circuit 25 and their functions are the same as those of the conventional ones, and therefore the description thereof will be omitted and different parts will be described. . A communication circuit 30 is provided between the bottom circuit 14 and the head circuit 16 of the boom cylinder 5, and an electromagnetic switching valve 32 having an ON-OFF switch 31 on the communication circuit 30, a throttle valve 33, a pilot hydraulic type. A first opening / closing valve 34 and a second opening / closing valve 35 are provided in series. A shuttle valve 41 for selectively introducing high-pressure oil is provided in a circuit 40 that connects the pilot hydraulic circuits 23 and 24. The circuit 40 and the pilot port 37 of the second opening / closing valve 35 are connected via the shuttle valve 41. It is connected by 42. A throttle valve 44 is arranged on a circuit 43 connecting the pilot port 36 of the first opening / closing valve 34 and the circuit 42.
【００１２】 つぎに作用について説明する。オペレータがＯＮ−ＯＦＦスイッチ３１をＯＮ にすると電磁切換弁３２はＢ位置となり開になる。そして、たとえば、パイロッ ト油圧操作弁２１の操作レバー２２を下げＤ側に操作するとパイロット油圧回路 ２４の油圧は下げ側パイロットポート１３に至り方向制御弁１１を左に移動する 。方向制御弁１１はＤ位置となって圧力油はヘッド回路１６を経てブームシリン ダ５のヘッド側油室１７に供給され、ボトム側油室１５はボトム回路１４を経て オイルタンク１８に連通してブームシリンダ５は縮んでブーム４は下降する。こ のとき、パイロット油圧回路２３はドレン回路２５を介してオイルタンク１８と 連通しており油圧は低い。したがって、シャトルバルブ４１は高圧のパイロット 油圧回路２４の油を回路４２、４３に送る。第２開閉弁３５は右に移動してＢ位 置となり閉じる。第１開閉弁３４は絞り弁４４を経て僅かに遅れて右に移動し、 Ｂ位置となって開く。しかしながら、前述のごとく第２開閉弁３４が閉じている ため連通回路３０は閉じており、従来のものと同一の通常状態となっている。Next, the operation will be described. When the operator turns ON the ON-OFF switch 31, the electromagnetic switching valve 32 is in the B position and is opened. Then, for example, when the operation lever 22 of the pilot oil pressure operation valve 21 is lowered and operated to the D side, the oil pressure of the pilot hydraulic circuit 24 reaches the lower pilot port 13 and moves the directional control valve 11 to the left. The directional control valve 11 is in the D position and pressure oil is supplied to the head side oil chamber 17 of the boom cylinder 5 through the head circuit 16, and the bottom side oil chamber 15 communicates with the oil tank 18 through the bottom circuit 14. The boom cylinder 5 contracts and the boom 4 descends. At this time, the pilot hydraulic circuit 23 communicates with the oil tank 18 via the drain circuit 25, and the hydraulic pressure is low. Therefore, the shuttle valve 41 sends the high-pressure pilot hydraulic circuit 24 oil to the circuits 42, 43. The second on-off valve 35 moves to the right to be in the B position and is closed. The first on-off valve 34 moves to the right via the throttle valve 44 with a slight delay, and opens to the B position. However, since the second opening / closing valve 34 is closed as described above, the communication circuit 30 is closed, and the normal state is the same as the conventional one.
【００１３】 操作レバー２２を中立Ｎの位置に戻すとパイロット回路２３、２４はともにオ イルタンク１８に連通し、油圧は下がって方向制御弁１１はＮ位置となり、ボト ム、ヘッド回路１４、１６は閉じてブームシリンダ５は停止し、ブーム下降は停 止する。回路４２もオイルタンク１８に連通し、油圧は低下して第２開閉弁３５ は左に移動し、Ａ位置となって回路は開く。回路４３の圧油は絞り弁４４を通る ため直ちに油圧が低下せず、時間遅れが生ずる。すなわち、第１開閉弁３４がＡ 位置となって回路を閉じるまでの間はブームシリンダ５のボトム側油室１５とヘ ッド側油室１７とを連通する連通回路３０は絞り弁３３を介して連通する。 方向制御弁１１がＮ位置に切り換わると前述のごとく作業機の慣性でボトム側 油室１５の油圧は急激に上昇しようとする。しかしながら、このとき、連通回路 ３０は開いているため、ボトム側油室１５の油は絞り弁３３を介して極めて少量 ヘッド側油室１７に逃げ、図３（ｃ）の点線に示すようにピーク圧Ｐ1 はＰ3 に 低下する。しかしながら、ボトム側油室１５の油圧の反動のため、つぎにヘッド 側油室１７の油圧が高くなるが、同様にしてヘッド側油室１７の油を少量ボトム 側油室１５に逃がし、図３（ｄ）の点線に示すようにピーク圧Ｐ2 はＰ4 に低下 する。この動作は回路４３の油が絞り弁４４を通ってオイルタンク１８の油圧と 等しくなるまで続き、第１開閉弁３４がＡ位置に戻った時点で連通回路３０は閉 じ、通常状態となる。このようにしてブームシリンダ５内の油圧の変動は減少し 、作業機の振動は大幅に抑制される。When the operating lever 22 is returned to the neutral N position, the pilot circuits 23 and 24 both communicate with the oil tank 18, the hydraulic pressure decreases, the directional control valve 11 moves to the N position, and the bottom and head circuits 14 and 16 When closed, the boom cylinder 5 is stopped and the boom lowering is stopped. The circuit 42 also communicates with the oil tank 18, the hydraulic pressure decreases, the second opening / closing valve 35 moves to the left, and the circuit is opened at the A position. Since the pressure oil in the circuit 43 passes through the throttle valve 44, the oil pressure does not immediately drop and a time delay occurs. That is, the communication circuit 30 that connects the bottom side oil chamber 15 and the head side oil chamber 17 of the boom cylinder 5 through the throttle valve 33 until the first opening / closing valve 34 is in the A position and the circuit is closed. Communicate with each other. When the directional control valve 11 is switched to the N position, the hydraulic pressure of the bottom side oil chamber 15 will suddenly rise due to the inertia of the working machine as described above. However, at this time, since the communication circuit 30 is open, a very small amount of oil in the bottom side oil chamber 15 escapes to the head side oil chamber 17 via the throttle valve 33, and a peak occurs as shown by the dotted line in FIG. 3 (c). The pressure P 1 drops to P 3 . However, due to the reaction of the hydraulic pressure in the bottom side oil chamber 15, the hydraulic pressure in the head side oil chamber 17 next rises. Similarly, a small amount of the oil in the head side oil chamber 17 is released to the bottom side oil chamber 15 and the oil in the head side oil chamber 17 is released. As shown by the dotted line in (d), the peak pressure P 2 drops to P 4 . This operation continues until the oil in the circuit 43 passes through the throttle valve 44 and becomes equal to the oil pressure in the oil tank 18, and when the first opening / closing valve 34 returns to the A position, the communication circuit 30 closes and enters the normal state. In this way, the fluctuation of the hydraulic pressure in the boom cylinder 5 is reduced, and the vibration of the working machine is significantly suppressed.
【００１４】 しかしながら、上述のごとき振動抑制を行うと不具合を生ずる場合がある。た とえば、作業機の上げ下げを繰り返して転圧作業を行うような場合、振動抑制装 置を作動させると作業機の動きが緩慢になり、オペレータの感覚と一致しない場 合が生ずる。このような場合にはＯＮ−ＯＦＦスイッチ３１をＯＦＦにして電磁 切換弁３２をＡ位置に切り換えて連通回路３０を閉じ、従来のものと全く同一の 状態にして作業する。However, if the vibration suppression as described above is performed, a problem may occur. For example, when performing rolling compaction work by repeatedly raising and lowering the work implement, the movement of the work implement becomes slow when the vibration suppression device is activated, which may not match the operator's feeling. In such a case, the ON-OFF switch 31 is turned OFF, the electromagnetic switching valve 32 is switched to the A position, the communication circuit 30 is closed, and the work is performed in the same state as the conventional one.
【００１５】 上記の装置の内、電磁切換弁３２は手動式の切換弁でも差し支えない。また、 パイロット油圧式の開閉弁３４、３５は電磁、パイロット油圧併用式の開閉弁で あってもよい。Of the above devices, the electromagnetic switching valve 32 may be a manual switching valve. Further, the pilot hydraulic on-off valves 34 and 35 may be electromagnetic and pilot hydraulic on-off valves.
【００１６】 上述の第１実施例に説明した振動抑制装置の性能は絞り弁３３と４４の性能に 影響されること大である。回路を流れる油の粘度によって絞り弁３３、４４の特 性は変化を受けることは周知の通りであり、粘度の高い場合（作動油温の低い場 合）には絞り弁３３、４４を通過する油量は著しく少なくなり、作業機の動作が オペレータの意図と異なる場合が生じる。 図２は上記問題に対処するための第２実施例の油圧回路図であり、電磁切換弁 ３２のＯＮ−ＯＦＦスイッチ３１の回路３８に温度センサ５０、５１を介装して ある。その他の部分は第１実施例と同一なので説明は省略する。この温度センサ ５０、５１は油温が低温のときにＯＦＦになるようになっている。温度検出場所 は、たとえば回路４３の絞り弁４４付近、および連通回路３０の絞り弁３３付近 とし、いずれかの油温が絞り弁３３あるいは４４の性能に悪影響をおよぼすと思 われる温度に達するとＯＦＦになるようにしておく。このようにすることにより 、低温時にはオペレータがＯＮ−ＯＦＦスイッチ３１をＯＮにしても連通回路は 連通せず、低温時の作動で危険な現象が発生することを未然に防止することがで きる。The performance of the vibration suppressing device described in the first embodiment is largely influenced by the performance of the throttle valves 33 and 44. It is well known that the characteristics of the throttle valves 33 and 44 change depending on the viscosity of the oil flowing through the circuit. When the viscosity is high (when the hydraulic oil temperature is low), the throttle valves 33 and 44 pass through. The amount of oil is significantly reduced, and the operation of the work equipment may be different from the operator's intention. FIG. 2 is a hydraulic circuit diagram of the second embodiment for coping with the above problem, in which the temperature sensor 50, 51 is provided in the circuit 38 of the ON-OFF switch 31 of the electromagnetic switching valve 32. Since the other parts are the same as those in the first embodiment, the description thereof will be omitted. The temperature sensors 50 and 51 are turned off when the oil temperature is low. The temperature detection location is, for example, in the vicinity of the throttle valve 44 of the circuit 43 and in the vicinity of the throttle valve 33 of the communication circuit 30, and is turned off when any oil temperature reaches a temperature at which the performance of the throttle valve 33 or 44 is considered to be adversely affected. To be By doing so, even if the operator turns on the ON-OFF switch 31 at low temperature, the communication circuit does not communicate, and it is possible to prevent a dangerous phenomenon from occurring during operation at low temperature.
【００１７】[0017]
以上詳述したごとく、本考案は本体に揺動自在に装着された作業機を昇降自在 に支持する油圧シリンダと、油圧シリンダに供給する圧油を制御するパイロット 油圧式方向制御弁と、パイロット油圧式方向制御弁を制御するパイロット油圧操 作弁とを備えた建設機械の油圧回路において、油圧シリンダのヘッド側とボトム 側とを連通する連通回路を設け、連通回路上に絞り弁と、連通回路を開閉する切 換弁と、パイロット油圧を受けて回路を開く第１開閉弁と、パイロット油圧を受 けて回路を閉じる第２開閉弁とを直列に介装した。そして、パイロット油圧操作 弁のパイロット油圧回路と、第１、第２開閉弁のパイロットポートとをシャトル バルブを介して接続する回路を設け、第１開閉弁に接続する回路上に絞り弁を設 けた。 そのため、オペレータが切換弁を開にすると、作業機の作動停止時に油圧シリ ンダのヘッド側とボトム側とを連通する連通回路が短時間連通し、油圧シリンダ のピーク圧を発生した側の油を微量だけ他の側に逃がし、ピーク圧を低減して振 動を抑制し、オペレータの疲労を軽減できる。 オペレータが切換弁を閉にすると、油圧シリンダのヘッド側とボトム側との連 通回路は閉じられ従来の油圧回路と同一となるため、作動遅れが生じることはな く、短時間のうちに作業機の上げ下げの繰り返しが可能となる。 また、連通回路上に電磁切換弁を介装し、電磁切換弁の電気回路上にＯＮ−Ｏ ＦＦスイッチと、予め定められた油温に達すると回路をカットする温度センサと を設けたため、油が低温となり絞り弁に悪い影響を与える予め定めた温度に達す ると電気回路はカットされ、ＯＮ−ＯＦＦスイッチを操作しても連通回路は常に 閉じていて低温時に危険な作動をすることを防止できる。 以上のような効果を奏する振動抑制装置を経済的に得ることができる。 As described in detail above, the present invention provides a hydraulic cylinder for swingably supporting a working machine mounted on a main body, a pilot hydraulic directional control valve for controlling pressure oil supplied to the hydraulic cylinder, and a pilot hydraulic pressure. In a hydraulic circuit of a construction machine equipped with a pilot hydraulic operation valve that controls a directional control valve, a communication circuit that connects the head side and the bottom side of a hydraulic cylinder is provided, and a throttle valve and a communication circuit are provided on the communication circuit. A switching valve that opens and closes the valve, a first opening and closing valve that receives the pilot hydraulic pressure to open the circuit, and a second opening and closing valve that receives the pilot hydraulic pressure and closes the circuit are interposed in series. Then, a circuit for connecting the pilot hydraulic circuit of the pilot hydraulic operating valve and the pilot ports of the first and second opening / closing valves via a shuttle valve was provided, and a throttle valve was provided on the circuit connecting to the first opening / closing valve. . Therefore, when the operator opens the switching valve, the communication circuit that connects the head side and the bottom side of the hydraulic cylinder communicates for a short time when the working machine stops operating, and the oil on the side that generated the peak pressure of the hydraulic cylinder is released. Only a small amount can be released to the other side, peak pressure can be reduced, vibration can be suppressed, and operator fatigue can be reduced. When the operator closes the switching valve, the communication circuit between the head side and the bottom side of the hydraulic cylinder is closed, and the hydraulic circuit is the same as the conventional hydraulic circuit. It is possible to repeatedly raise and lower the machine. In addition, an electromagnetic switching valve is installed on the communication circuit, and an ON-OFF switch and a temperature sensor that cuts the circuit when a predetermined oil temperature is reached are provided on the electric circuit of the electromagnetic switching valve. When the temperature reaches a preset temperature that causes a low temperature and adversely affects the throttle valve, the electric circuit is cut off and the communication circuit is always closed even if the ON-OFF switch is operated, preventing dangerous operation at low temperatures. it can. It is possible to economically obtain the vibration suppressing device that achieves the above effects.
【図１】本考案の振動抑制装置の第１実施例を示すブー
ムシリンダ駆動油圧回路図である。FIG. 1 is a boom cylinder drive hydraulic circuit diagram showing a first embodiment of a vibration suppressing device of the present invention.
【図２】本考案の振動抑制装置の第２実施例を示すブー
ムシリンダ駆動油圧回路図である。FIG. 2 is a boom cylinder drive hydraulic circuit diagram showing a second embodiment of the vibration suppressing device of the present invention.
【図３】本考案の振動抑制装置の効果を示すブームシリ
ンダ駆動タイムチャートである。FIG. 3 is a boom cylinder drive time chart showing the effect of the vibration suppressing device of the present invention.
【図４】油圧ショベルの全体側面図である。FIG. 4 is an overall side view of the hydraulic excavator.
【図５】従来の油圧ショベルのブームシリンダ駆動油圧
回路図である。FIG. 5 is a boom cylinder drive hydraulic circuit diagram of a conventional hydraulic excavator.
５ ブームシリンダ １１ 方向制御弁 １４ ボトム回路 １６ ヘッド回路 ２１ パイロット油圧操作弁 ２３、２４ パイロット油圧回路 ３０ 連通回路 ３１ ＯＮ−ＯＦＦスイッチ ３２ 電磁切換弁 ３３、４４ 絞り弁 ３４ 第１開閉弁 ３５ 第２開閉弁 ４１ シャトルバルブ ４２、４３ 回路 ５０、５１ 温度センサ 5 Boom cylinder 11 Directional control valve 14 Bottom circuit 16 Head circuit 21 Pilot hydraulic operation valve 23, 24 Pilot hydraulic circuit 30 Communication circuit 31 ON-OFF switch 32 Electromagnetic switching valve 33, 44 Throttle valve 34 First opening / closing valve 35 Second opening / closing Valve 41 Shuttle valve 42, 43 Circuit 50, 51 Temperature sensor
Claims (3)
降自在に支持する油圧シリンダと、油圧源から該油圧シ
リンダに供給する圧油を制御するパイロット油圧式方向
制御弁と、該方向制御弁を制御するパイロット油圧操作
弁とを備えた建設機械の油圧回路において、前記油圧シ
リンダのヘッド側とボトム側とを連通する連通回路を設
け、前記連通回路上に絞り弁と、前記連通回路を開閉す
る切換弁と、パイロット油圧式の第１開閉弁および第２
開閉弁とを直列に介装することを特徴とする作業機の振
動抑制装置。1. A hydraulic cylinder for swingably supporting a working machine mounted on a main body, a pilot hydraulic directional control valve for controlling pressure oil supplied from a hydraulic source to the hydraulic cylinder, and the direction. In a hydraulic circuit of a construction machine equipped with a pilot hydraulic operating valve for controlling a control valve, a communication circuit that connects the head side and the bottom side of the hydraulic cylinder is provided, and a throttle valve and the communication circuit are provided on the communication circuit. Switching valve for opening and closing the valve, and a pilot hydraulic first opening and closing valve and a second
A vibration suppressing device for a working machine, which is provided with an on-off valve in series.
油圧回路と、パイロット油圧を受けて前記連通回路を開
く前記第１開閉弁のパイロットポートと、パイロット油
圧を受けて前記連通回路を閉じる第２開閉弁のパイロッ
トポートとを、高圧側の油を選択導入するシャトルバル
ブを介して接続し、前記パイロット油圧回路と、前記第
１開閉弁のパイロットポートとを連通する回路上に絞り
弁を介装することを特徴とする請求項１の作業機の振動
抑制装置。2. A pilot hydraulic circuit for the pilot hydraulic operating valve, a pilot port for the first opening / closing valve that receives the pilot hydraulic pressure to open the communication circuit, and a second opening / closing valve that receives the pilot hydraulic pressure and closes the communication circuit. And a pilot port of the first opening / closing valve are connected to each other through a shuttle valve that selectively introduces high-pressure oil, and a throttle valve is provided on a circuit that connects the pilot hydraulic circuit and the pilot port of the first opening / closing valve. The vibration suppressing device for a working machine according to claim 1.
降自在に支持する油圧シリンダと、油圧源から該油圧シ
リンダに供給する圧油を制御するパイロット油圧式方向
制御弁と、該方向制御弁を制御するパイロット油圧操作
弁とを備えた建設機械の油圧回路において、前記油圧シ
リンダのヘッド側とボトム側とを連通する連通回路を設
け、前記連通回路上に絞り弁と、前記連通回路を開閉す
る電磁切換弁と、パイロット油圧式の第１開閉弁および
第２開閉弁とを直列に介装し、前記電磁切換弁に接続す
る電気回路上にＯＮ−ＯＦＦスイッチと、予め定められ
た油温に達すると信号を受けて前記電気回路をカットす
る温度センサとを配設することを特徴とする作業機の振
動抑制装置。3. A hydraulic cylinder for supporting a working machine which is swingably mounted on a main body so as to be able to move up and down, a pilot hydraulic directional control valve for controlling pressure oil supplied from a hydraulic source to the hydraulic cylinder, and the direction. In a hydraulic circuit of a construction machine equipped with a pilot hydraulic operating valve for controlling a control valve, a communication circuit that connects the head side and the bottom side of the hydraulic cylinder is provided, and a throttle valve and the communication circuit are provided on the communication circuit. An electromagnetic switching valve for opening and closing the valve, a pilot hydraulic first opening and closing valve, and a second opening and closing valve are interposed in series, and an ON-OFF switch is provided on an electric circuit connected to the electromagnetic switching valve. A vibration suppressing device for a working machine, comprising: a temperature sensor that receives a signal when the oil temperature is reached and cuts the electric circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4827193U JPH0714202U (en) | 1993-08-13 | 1993-08-13 | Vibration suppressor for work equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4827193U JPH0714202U (en) | 1993-08-13 | 1993-08-13 | Vibration suppressor for work equipment |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0714202U true JPH0714202U (en) | 1995-03-10 |
Family
ID=12798786
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4827193U Pending JPH0714202U (en) | 1993-08-13 | 1993-08-13 | Vibration suppressor for work equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0714202U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1298256A3 (en) * | 2001-09-28 | 2005-06-15 | Kobelco Construction Machinery Co., Ltd. | Hydraulic system for suppression of vibrations of a working machine |
| KR20190056629A (en) * | 2017-11-17 | 2019-05-27 | 현대건설기계 주식회사 | Hydraulic Control Device FOR CONSTRUCTION MACHINERY |
-
1993
- 1993-08-13 JP JP4827193U patent/JPH0714202U/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1298256A3 (en) * | 2001-09-28 | 2005-06-15 | Kobelco Construction Machinery Co., Ltd. | Hydraulic system for suppression of vibrations of a working machine |
| KR20190056629A (en) * | 2017-11-17 | 2019-05-27 | 현대건설기계 주식회사 | Hydraulic Control Device FOR CONSTRUCTION MACHINERY |
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