JPH09287172A - Regenerative circuit of hydraulic machine - Google Patents

Regenerative circuit of hydraulic machine

Info

Publication number
JPH09287172A
JPH09287172A JP8100117A JP10011796A JPH09287172A JP H09287172 A JPH09287172 A JP H09287172A JP 8100117 A JP8100117 A JP 8100117A JP 10011796 A JP10011796 A JP 10011796A JP H09287172 A JPH09287172 A JP H09287172A
Authority
JP
Japan
Prior art keywords
pressure
valve
hydraulic
control valve
hydraulic cylinder
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
Application number
JP8100117A
Other languages
Japanese (ja)
Other versions
JP3457798B2 (en
Inventor
欣也 ▲高▼橋
Kinya Takahashi
Yusaku Nozawa
勇作 野沢
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hitachi Construction Machinery Co Ltd
Original Assignee
Hitachi Construction Machinery Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hitachi Construction Machinery Co Ltd filed Critical Hitachi Construction Machinery Co Ltd
Priority to JP10011796A priority Critical patent/JP3457798B2/en
Publication of JPH09287172A publication Critical patent/JPH09287172A/en
Application granted granted Critical
Publication of JP3457798B2 publication Critical patent/JP3457798B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Landscapes

  • Operation Control Of Excavators (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a regenerative circuit which can operate stably at a practically constant speed even if latent pressure remains. SOLUTION: A selector valve 8 is provided in a main pipeline 5 between a hydraulic cylinder 2 and a flow control valve 3. A shuttle valve 11 selects the higher of either a bottom side pressure or the exit side pressure of the selector valve 8 and introduces it to the pressure chamber 102 of a regenerative valve 10. A flow control valve 3 is positioned as shown in the figure, and if a differential pressure before and after the fixed restrictor 81 of the selector valve 8 is higher than a preset value, the regenerative valve 10 opens and flows rod side oil to the bottom side and accelerates a hydraulic cylinder 2. When a control lever 12 is operated while latent pressure exists in the main pipeline, the latent pressure is introduced to a pilot chamber 83 of the selector valve 8 through the shuttle valve 11 and the pilot circuit 16, switches the selector valve 8 to the conduction side 82, reduces differential pressure before and after the restrictor to zero, closes the regenerative valve 10 and prevents the hydraulic cylinder 2 from accelerating.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、油圧ショベル等の油圧
機械に備えられている油圧シリンダを、当該油圧シリン
ダがタンクに排出する圧油を利用(再生)して増速させ
るための油圧機械の再生回路に関する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic machine for increasing the speed of a hydraulic cylinder provided in a hydraulic machine such as a hydraulic excavator by utilizing (reproducing) pressure oil discharged from the hydraulic cylinder to a tank. Of the reproduction circuit of.

【0002】[0002]

【従来の技術】油圧シリンダにより駆動される機構には
数多くの種類がある。例えば、油圧ショベルにあって
は、ブーム、アーム、バケット、このバケットの代わり
に取り付けられる種々のアタッチメント等がある。これ
らの機構のなかには、その作業過程中、作業速度の増大
が要求される機構がある。例えば、上記アタッチメント
として用いられる破砕機は破砕対象となる物体を砕く機
構であるが、作業効率上、当該物体を挟むまでは高速で
駆動されるのが望ましい。
There are many types of mechanisms driven by hydraulic cylinders. For example, in a hydraulic excavator, there are a boom, an arm, a bucket, various attachments attached in place of the bucket, and the like. Among these mechanisms, there is a mechanism that requires an increase in working speed during the working process. For example, the crusher used as the attachment has a mechanism for crushing an object to be crushed, but it is desirable to drive at high speed until the object is sandwiched in terms of work efficiency.

【0003】さらに、増速の要望は次の例のような場合
にも存在する。即ち、アタッチメントを本体に取り付け
て駆動する場合、当該アタッチメントの設計上の最高圧
力が本体の最高圧力より低い場合、アタッチメントへの
圧油の供給量が小さくなり、作業速度が低下するおそれ
がある。このような場合もアタッチメントの増速が求め
られる。
Further, the demand for speeding up also exists in the following cases. That is, when the attachment is mounted on the main body and driven, if the designed maximum pressure of the attachment is lower than the maximum pressure of the main body, the amount of pressure oil supplied to the attachment may be small, and the work speed may be reduced. Even in such a case, it is required to speed up the attachment.

【0004】このように増速の要求に応じる手段とし
て、油圧シリンダのロッド側の油を切換弁を用いてボト
ム側へ還流することにより、同一のポンプ油量でシリン
ダロッドが伸びる速度を増速することができ、又は、少
ないポンプ油量でもより大きな速度が得られる再生回路
が、例えば特願平6−137138号で提案されてい
る。この再生回路を図2により説明する。
As a means for responding to the request for acceleration, the oil on the rod side of the hydraulic cylinder is circulated to the bottom side by using the switching valve to increase the speed at which the cylinder rod extends with the same amount of pump oil. A regenerating circuit that can achieve this or can obtain a higher speed with a small amount of pump oil is proposed in, for example, Japanese Patent Application No. 6-137138. This reproducing circuit will be described with reference to FIG.

【0005】図2は従来の再生回路を有する油圧機械の
油圧回路図である。この図で、1は可変容量油圧ポンプ
(以下単に油圧ポンプという)、1aは油圧ポンプ1の
おしのけ容積可変機構(以下斜板で代表させる)、2は
油圧ポンプ1により駆動される油圧シリンダ、3は油圧
シリンダ2の駆動方向および駆動速度を制御する流量制
御弁、4は流量制御弁3と油圧シリンダのボトム側とを
連結する主回路、5は流量制御弁3と油圧シリンダのロ
ッド側とを連結する主回路、6は斜板1aの傾転を制御
するレギュレータである。レギュレータ6は、一方側に
油圧ポンプ1の吐出圧を導入し、他方にばね61aを備
えるとともに油圧シリンダ2の負荷圧を導入する傾転制
御弁61、および斜板1aに連結され傾転制御弁61の
作動に応じて駆動制御される傾転駆動アクチュエータ6
2で構成されている。
FIG. 2 is a hydraulic circuit diagram of a hydraulic machine having a conventional regeneration circuit. In this figure, 1 is a variable displacement hydraulic pump (hereinafter simply referred to as hydraulic pump), 1a is a variable displacement mechanism for the hydraulic pump 1 (hereinafter represented by a swash plate), 2 is a hydraulic cylinder driven by the hydraulic pump 1, 3 Is a flow control valve for controlling the drive direction and drive speed of the hydraulic cylinder 2, 4 is a main circuit connecting the flow control valve 3 and the bottom side of the hydraulic cylinder, 5 is the flow control valve 3 and the rod side of the hydraulic cylinder. A main circuit 6 to be connected is a regulator for controlling tilting of the swash plate 1a. The regulator 6 includes a tilt control valve 61 that introduces the discharge pressure of the hydraulic pump 1 on one side and a spring 61a on the other side, and introduces the load pressure of the hydraulic cylinder 2, and a tilt control valve that is connected to the swash plate 1a. Tilt drive actuator 6 that is driven and controlled according to the operation of 61
It is composed of two.

【0006】8は主回路5に挿入される切換弁である。
この切換弁8は、固定絞り側81、導通側82、パイロ
ット室83、およびばね84より成り、パイロット室8
3の圧力が設定値を超えると図示の絞り側から導通側へ
切り換えられる。なお、切換弁8の導入側の主回路5の
配管が5aで、出口側の配管が5bで示されている。9
は切換弁8と並列に接続されたチェック弁、10は再生
弁である。再生弁10は、切換弁8の導入側圧力が導か
れる圧力室101、切換弁8の出口側圧力が導かれる圧
力室102、圧力室101と主回路4との間の連通を遮
断するシート部103、および当該シート部103を遮
断方向に付勢するばね104で構成されている。なお、
主回路4の圧力が再生弁10を通って切換弁8のパイロ
ット室83へ導入される。
A switching valve 8 is inserted in the main circuit 5.
The switching valve 8 includes a fixed throttle side 81, a conduction side 82, a pilot chamber 83, and a spring 84.
When the pressure of 3 exceeds the set value, the throttle side shown in the figure is switched to the conduction side. The piping of the main circuit 5 on the introduction side of the switching valve 8 is indicated by 5a, and the piping on the outlet side is indicated by 5b. 9
Is a check valve connected in parallel with the switching valve 8 and 10 is a regeneration valve. The regeneration valve 10 includes a pressure chamber 101 to which the pressure on the introduction side of the switching valve 8 is guided, a pressure chamber 102 to which the pressure on the outlet side of the switching valve 8 is guided, and a seat portion that blocks communication between the pressure chamber 101 and the main circuit 4. 103 and a spring 104 that biases the seat 103 in the blocking direction. In addition,
The pressure in the main circuit 4 is introduced into the pilot chamber 83 of the switching valve 8 through the regeneration valve 10.

【0007】11は主回路4の圧力および切換弁8の出
口側圧力のうち大きい方の圧力を選択してこれを圧力室
102へ導くシャトル弁である。12は油圧シリンダ2
を操作する操作レバー、12aは操作レバ12を矢印X
方向に操作したときその操作量に応じて出力されるパイ
ロット圧を流量制御弁3の左側パイロット室へ導入する
パイロット管路、12bは操作レバ12を矢印Y方向に
操作したときその操作量に応じて出力されるパイロット
圧を流量制御弁3の右側パイロット室へ導入するパイロ
ット管路である。13は油圧ポンプ1の吐出回路に接続
されたアンロード弁、14は主回路4、5に接続されて
それらの最大圧力を規定するリリーフ弁である。
Reference numeral 11 is a shuttle valve that selects the larger pressure of the main circuit 4 pressure and the outlet side pressure of the switching valve 8 and guides it to the pressure chamber 102. 12 is a hydraulic cylinder 2
The operation lever 12a operates the operation lever 12 with an arrow X.
The pilot line for introducing the pilot pressure, which is output according to the operation amount in the direction Y, into the left pilot chamber of the flow control valve 3, 12b corresponds to the operation amount when the operation lever 12 is operated in the arrow Y direction. This is a pilot conduit for introducing the pilot pressure output as a result into the right pilot chamber of the flow control valve 3. Reference numeral 13 is an unload valve connected to the discharge circuit of the hydraulic pump 1, and 14 is a relief valve connected to the main circuits 4 and 5 to regulate their maximum pressures.

【0008】ここで、流量制御弁3の構成、レギュレー
タ6の動作、および切換弁8の動作の概略について順に
説明する。流量制御弁3の開口面積はそのストローク量
により変化し、この開口面積による絞りが図に可変絞り
31、32で表わされている。又、ストローク量と開口
面積との関係が図3に示されている。図3で横軸にはス
トローク量Sが、縦軸には開口面積ai 、ao がとって
ある。開口面積ai は流入側の、又開口面積ao は戻り
側の開口面積を示す。ストローク量Sが大きくなると開
口面積ai は飛躍的に大きくなるが、開口面積ao は僅
かに大きくなるだけである。これは、油圧シリンダ2に
負圧が作用しているとき、例えばロッドが伸長方向に引
っ張られている場合、操作レバーがその方向(矢印Y方
向)へ操作されたときに負荷が逸走するのを防止するた
めに設定されたものである。又、開口面積ao の最大値
は切換弁8の固定絞り81の開口面積より小さくなるよ
うに選定されている。
Here, the outline of the structure of the flow control valve 3, the operation of the regulator 6, and the operation of the switching valve 8 will be described in order. The opening area of the flow control valve 3 changes depending on its stroke amount, and the diaphragms based on this opening area are represented by variable diaphragms 31 and 32 in the figure. Further, the relationship between the stroke amount and the opening area is shown in FIG. In FIG. 3, the horizontal axis represents the stroke amount S, and the vertical axis represents the opening areas a i and a o . The opening area a i shows the opening area on the inflow side, and the opening area a o shows the opening area on the return side. As the stroke amount S increases, the opening area a i increases dramatically, but the opening area a o only increases slightly. This is because when negative pressure acts on the hydraulic cylinder 2, for example, when the rod is pulled in the extension direction, the load escapes when the operation lever is operated in that direction (arrow Y direction). It is set to prevent. The maximum value of the opening area a o is selected to be smaller than the opening area of the fixed throttle 81 of the switching valve 8.

【0009】一方、流量制御弁3の出力側圧力(負荷
圧)はレギュレータ6の傾転制御弁61の一方端に導か
れ、これにより、傾転駆動アクチュエータ62は油圧ポ
ンプ1の吐出圧が流量制御弁3の前後の差圧として設定
された圧力より少し高い圧力(ばね61aで設定された
圧力)になるように斜板1aの傾転を制御する。なお、
操作レバー12が中立位置にあり、斜板1aの傾転角が
最少であるとき油圧ポンプ1の吐出圧は最少圧力に保持
される。
On the other hand, the output side pressure (load pressure) of the flow control valve 3 is guided to one end of the tilt control valve 61 of the regulator 6, whereby the tilt drive actuator 62 receives the discharge pressure of the hydraulic pump 1. The tilting of the swash plate 1a is controlled so that the pressure is a little higher than the pressure set as the differential pressure across the control valve 3 (the pressure set by the spring 61a). In addition,
When the operation lever 12 is in the neutral position and the tilt angle of the swash plate 1a is the minimum, the discharge pressure of the hydraulic pump 1 is kept at the minimum pressure.

【0010】又、切換弁8は、主回路4の圧力が切換弁
8のばね84で設定される圧力以下の場合は固定絞り8
1側へ切り換えられ、当該圧力を超える場合は導通側8
2へ切り換えられる。固定絞り81を通過する流量は、
圧力室101、102に導かれる固定絞り81の前後の
差圧と一対一に対応するので、当該流量としてある所定
流量を設定しようとするとき、この所定流量は、固定絞
り81の開口面積と再生弁10のばね104の圧力を調
整することにより所定の差圧として設定することができ
る。このように設定された所定流量に対して、絞り81
にこれを超る流量が流れようとすると、固定絞り81の
前後の差圧が所定差圧を超えることになり、このとき再
生弁10が開いて油圧シリンダ2のボトム側とロッド側
とを導通させ、固定絞り81の前後差圧を所定の差圧に
保持しようとする。
The switching valve 8 has a fixed throttle 8 when the pressure in the main circuit 4 is equal to or lower than the pressure set by the spring 84 of the switching valve 8.
When the pressure is switched to 1 and exceeds the pressure, the conduction side 8
Switched to 2. The flow rate passing through the fixed throttle 81 is
Since there is a one-to-one correspondence with the differential pressure before and after the fixed throttle 81 guided to the pressure chambers 101 and 102, when the predetermined flow rate is set as the flow rate, the predetermined flow rate is equal to the opening area of the fixed throttle 81 and the regeneration. It can be set as a predetermined differential pressure by adjusting the pressure of the spring 104 of the valve 10. With respect to the predetermined flow rate set in this way, the throttle 81
When a flow rate exceeding this is about to flow, the differential pressure before and after the fixed throttle 81 exceeds a predetermined differential pressure, at which time the regeneration valve 10 opens and the bottom side of the hydraulic cylinder 2 and the rod side are electrically connected. Then, the differential pressure across the fixed throttle 81 is to be maintained at a predetermined differential pressure.

【0011】次に、上記油圧回路の動作を説明する。操
作レバー12を矢印X方向に操作すると、パイロット管
路12aにパイロット圧が発生し、流量制御弁3が図示
左側位置へ駆動され、油圧ポンプ1からの圧油は流量制
御弁3、チェック弁9を含む主回路5を経て油圧シリン
ダ2のロッド側へ供給され、ボトム側の圧油は主回路
4、流量制御弁3を経てタンクへ排出され、油圧シリン
ダ2はロッドを縮めるように駆動される。
Next, the operation of the hydraulic circuit will be described. When the operating lever 12 is operated in the direction of the arrow X, pilot pressure is generated in the pilot conduit 12a, the flow control valve 3 is driven to the left position in the drawing, and the pressure oil from the hydraulic pump 1 flows into the flow control valve 3 and the check valve 9. Is supplied to the rod side of the hydraulic cylinder 2 through the main circuit 5 including the above, the pressure oil on the bottom side is discharged to the tank through the main circuit 4 and the flow control valve 3, and the hydraulic cylinder 2 is driven so as to contract the rod. .

【0012】操作レバー12を矢印Y方向に操作する
と、パイロット管路12bにパイロット圧が発生し、流
量制御弁3が図示のように右側位置へ駆動され、油圧ポ
ンプ1からの圧油は流量制御弁3、主回路4を経て油圧
シリンダ2のボトム側へ供給され、ロッド側の圧油は切
換弁8、主回路5、流量制御弁3を経てタンクへ排出さ
れ、油圧シリンダ2のロッドが伸長する方向に駆動され
る。この間、流量制御弁3の前後差圧は一定に保持され
るので、主回路4に流れる流量は負荷の大小にかかわら
ず操作レバー12の操作量に応じた値となる。
When the operating lever 12 is operated in the direction of the arrow Y, pilot pressure is generated in the pilot conduit 12b, the flow control valve 3 is driven to the right position as shown in the drawing, and the pressure oil from the hydraulic pump 1 is flow controlled. It is supplied to the bottom side of the hydraulic cylinder 2 via the valve 3 and the main circuit 4, the pressure oil on the rod side is discharged to the tank via the switching valve 8, the main circuit 5 and the flow control valve 3, and the rod of the hydraulic cylinder 2 extends. Is driven in the direction During this period, the differential pressure across the flow control valve 3 is maintained constant, so that the flow rate of the main circuit 4 becomes a value according to the operation amount of the operation lever 12 regardless of the magnitude of the load.

【0013】今、主回路4の圧力が設定値以下で切換弁
8が固定絞り81側へ切り換えられている状態にある場
合、操作レバー12の操作量が大きくなり、切換弁8を
通過する油圧シリンダ2のロッド側からの流量が上記所
定流量を超えようとすると、上述のように再生弁10が
開き、ロッド側からの上記所定流量を超える分の流量の
圧油が再生弁10を通って主回路4からボトム側へ再流
入する。これにより、ボトム側に流れる流量は再流入分
だけ多くなり、その分だけ油圧シリンダ2を増速させる
ことになる。
When the pressure in the main circuit 4 is below the set value and the switching valve 8 is switched to the fixed throttle 81 side, the operation amount of the operating lever 12 increases and the hydraulic pressure passing through the switching valve 8 increases. When the flow rate from the rod side of the cylinder 2 is about to exceed the predetermined flow rate, the regeneration valve 10 opens as described above, and pressure oil having a flow rate exceeding the predetermined flow rate from the rod side passes through the regeneration valve 10. Re-inflow from the main circuit 4 to the bottom side. As a result, the flow rate on the bottom side increases by the amount of re-inflow, and the hydraulic cylinder 2 is accelerated accordingly.

【0014】又、この状態で、何らかの原因で瞬間的に
ボトム側の圧力が高くなると、この圧力はシャトル弁1
1により圧力室102に導入されて再生弁10を閉じ、
ボトム側からロッド側への瞬間的逆流を阻止する。さら
に、油圧シリンダ2の負荷が大きくなると切換弁8のパ
イロット室83の圧力が高くなり、切換弁8は導通側へ
切り換えられ、ロッド側の背圧を下げて推力を保持する
ことができる。又、操作レバー12が中立位置(流量制
御弁3が中立位置)にあるとき、油圧シリンダ2のロッ
ドが伸長される方向に負荷が作用した場合は、ボトム側
の圧力が低く切換弁8は絞り81側に維持され、かつ、
切換弁8の出口側は流量制御弁3により阻止状態にある
ので、切換弁8の流量は0で固定絞り81の前後差圧も
0となり、再生弁10は閉じ状態に維持される。したが
って、油圧シリンダ2のロッド側の圧油の排出路はな
く、上記の負荷が作用しても油圧シリンダ2の中立状態
は維持され、停止位置を確実に保持することができる。
なお、何らかの理由によりロッド側の圧力が異常に高く
なった場合はロッド側の圧油が固定絞り81を介してリ
リーフ弁14からタンクに排出され、同様にボトム側の
圧力が異常に高くなった場合はボトム側の圧油がリリー
フ弁14からタンクに排出され、配管や再生弁10等の
破損を防止する。
Further, in this state, if the pressure on the bottom side momentarily rises for some reason, this pressure is increased.
1 is introduced into the pressure chamber 102 to close the regeneration valve 10,
Prevents instantaneous backflow from the bottom side to the rod side. Further, when the load on the hydraulic cylinder 2 increases, the pressure in the pilot chamber 83 of the switching valve 8 increases, the switching valve 8 is switched to the conduction side, and the back pressure on the rod side can be reduced to hold the thrust. Further, when the operation lever 12 is in the neutral position (the flow control valve 3 is in the neutral position) and a load acts in the direction in which the rod of the hydraulic cylinder 2 is extended, the pressure on the bottom side is low and the switching valve 8 is throttled. Maintained on the 81 side, and
Since the outlet side of the switching valve 8 is blocked by the flow control valve 3, the flow rate of the switching valve 8 is 0, the differential pressure across the fixed throttle 81 is also 0, and the regenerative valve 10 is kept closed. Therefore, there is no pressure oil discharge passage on the rod side of the hydraulic cylinder 2, the neutral state of the hydraulic cylinder 2 is maintained even when the above-mentioned load is applied, and the stop position can be reliably maintained.
If the rod-side pressure becomes abnormally high for some reason, the rod-side pressure oil is discharged from the relief valve 14 to the tank via the fixed throttle 81, and similarly the bottom-side pressure becomes abnormally high. In this case, the pressure oil on the bottom side is discharged from the relief valve 14 to the tank to prevent damage to the piping, the regeneration valve 10 and the like.

【0015】[0015]

【発明が解決しようとする課題】上記の油圧回路におい
て、例えば、油圧シリンダ2を油圧ショベルのアームシ
リンダであるとすると、操作レバー12を矢印X方向に
操作し、流量制御弁3を図示左側位置に切り換えた場
合、油圧シリンダ2は縮み、アームが前方に押し出され
る。このとき、油圧シリンダ2がストロークエンドに到
達すると、油圧ポンプ1の圧力およびロッド側の圧力は
回路の最高圧力まで上昇する。この状態で操作レバー1
2を中立状態に戻すと、流量制御弁3も中立状態に戻る
が、ロッド側の主回路5の配管には高圧のこもり圧が残
る。この高圧のこもり圧は、流量制御弁3等におけるリ
ークによって、いずれはアームシリンダに作用する負荷
を保持できる圧力まで低下することになる。
In the above hydraulic circuit, for example, assuming that the hydraulic cylinder 2 is an arm cylinder of a hydraulic shovel, the operating lever 12 is operated in the direction of arrow X, and the flow control valve 3 is moved to the left position in the figure. When switched to, the hydraulic cylinder 2 contracts and the arm is pushed forward. At this time, when the hydraulic cylinder 2 reaches the stroke end, the pressure of the hydraulic pump 1 and the pressure on the rod side rise to the maximum pressure of the circuit. Operation lever 1 in this state
When 2 is returned to the neutral state, the flow rate control valve 3 is also returned to the neutral state, but high pressure mist pressure remains in the pipe of the main circuit 5 on the rod side. Due to the leak in the flow rate control valve 3 and the like, this high muffled pressure eventually drops to a pressure at which the load acting on the arm cylinder can be held.

【0016】上記のこもり圧が残っている状態で操作レ
バー12を矢印Y方向に操作すると、流量制御弁3は図
示のように右側位置に切り換えられ、配管5a、5bの
こもり圧が一挙にタンクに排出される状態となり、固定
絞り81の前後の差圧は極めて高くなる。同時に再生弁
10も、高くなった当該差圧に相当する開口量でそのシ
ート部103を開口し、大量の油をボトム側に流出させ
る。その後、こもり圧は瞬時にアームシリンダに作用す
る通常の負荷圧となり、固定絞り81の前後差圧が低下
し、再生弁10の開口量も低下し、これに伴ってボトム
側に再生する流量も低下することとなる。
When the operating lever 12 is operated in the direction of the arrow Y while the above-mentioned muffled pressure remains, the flow control valve 3 is switched to the right position as shown in the drawing, and the muffled pressure of the pipes 5a and 5b is changed all at once. The pressure difference before and after the fixed throttle 81 becomes extremely high. At the same time, the regeneration valve 10 also opens the seat portion 103 with an opening amount corresponding to the increased differential pressure, and causes a large amount of oil to flow to the bottom side. After that, the muffled pressure instantly becomes a normal load pressure that acts on the arm cylinder, the differential pressure across the fixed throttle 81 decreases, the opening amount of the regeneration valve 10 also decreases, and the flow rate of regeneration to the bottom side accordingly. Will be reduced.

【0017】ところで、上記こもり圧が残っている状態
でアームを引き込む作業を行なうと、その作業の開始直
後、上述のようにロッド側からボトム側への再生流量が
異常に多くなり、アームシリンダの速度も異常に速くな
る。このアームシリンダの増速は一瞬ではあるが、アー
ムシリンダの速度が速いのでアームの移動量は大きくな
ってしまい、作業上不都合が生じる場合がある。例え
ば、油圧ショベルの作業で、アーム引きとブーム上げを
同時に行ない、ブームの操作量を調整しながらバケット
の爪先を水平に引き込む作業(水平掘削作業)がある
が、作業開始直後にアームシリンダの速度が早過ぎると
ブーム上げのタイミングが遅れ、精度良く水平にバケッ
ト爪先を引き込むことができなくなる。又、アームを単
独に振り下ろす操作においても、作業開始直後にアーム
が大きな速度で動き、次いで急激に速度が遅くなるので
衝撃が発生し、円滑な操作ができなくなり、かつ、オペ
レータに不快感を与えることになる。
By the way, when the work of pulling in the arm is carried out with the above-mentioned muffled pressure remaining, immediately after the work is started, the regeneration flow rate from the rod side to the bottom side becomes abnormally large as described above, and the arm cylinder The speed also becomes abnormally high. Although the speed of the arm cylinder is increased for a moment, the speed of the arm cylinder is so high that the movement amount of the arm becomes large, which may cause inconvenience in work. For example, in hydraulic excavator work, there is a work (horizontal excavation work) in which the arm is pulled and the boom is raised at the same time, and the toe of the bucket is pulled horizontally while adjusting the operation amount of the boom. If it is too fast, the boom raising timing will be delayed, and it will not be possible to accurately pull in the bucket toes horizontally. Even when the arm is individually swung down, the arm moves at a high speed immediately after the work is started, and then the speed rapidly decreases, which causes an impact, which makes smooth operation impossible and makes the operator uncomfortable. Will be given.

【0018】本発明の目的は、上記従来技術における課
題を解決し、こもり圧が残っていても速度変化の少ない
安定した動作を行なうことができる油圧機械の再生回路
を提供することにある。
An object of the present invention is to solve the above-mentioned problems in the prior art, and to provide a regenerating circuit for a hydraulic machine capable of performing a stable operation with a small speed change even if a muffled pressure remains.

【0019】[0019]

【課題を解決するための手段】上記の目的を達成するた
め、本発明は、油圧ポンプと、この油圧ポンプにより駆
動される油圧アクチュエータと、前記油圧ポンプと前記
油圧アクチュエータとの間に介在し当該油圧アクチュエ
ータの駆動を制御する流量制御弁と、前記油圧アクチュ
エータの一方側管路と他方側管路との間の導通、遮断を
行う再生弁と、前記一方側管路と前記流量制御弁との間
に介在するとともに、パイロット室を有しこのパイロッ
ト室に導入される圧力が予め定められた設定値以下であ
るとき前記一方側管路と前記流量制御弁との間の油圧回
路の状態を導通状態から絞り状態へ切り換える切換弁
と、前記他方側管路の圧力と前記切換弁の出口圧力のう
ち高い方の圧力を前記再生弁の室へ導入するパイロット
管路とで構成されている油圧機械の再生回路において、
前記パイロット管路の圧力と同一圧力を前記切換弁の前
記パイロット室へ導入することを特徴とする。
In order to achieve the above object, the present invention provides a hydraulic pump, a hydraulic actuator driven by the hydraulic pump, and an intervening device between the hydraulic pump and the hydraulic actuator. A flow rate control valve for controlling the drive of the hydraulic actuator, a regeneration valve for connecting and disconnecting the one side pipeline and the other side pipeline of the hydraulic actuator, and the one side pipeline and the flow rate control valve When the pressure introduced into the pilot chamber is not greater than a predetermined set value, the hydraulic circuit between the one side conduit and the flow control valve is electrically connected. A switching valve for switching from the state to the throttled state, and a pilot line for introducing the higher pressure of the pressure in the other side line and the outlet pressure of the switching valve into the chamber of the regeneration valve. In the hydraulic machine of regeneration circuit that,
The same pressure as the pressure in the pilot line is introduced into the pilot chamber of the switching valve.

【0020】[0020]

【発明の実施の形態】以下本発明を図示の実施の形態に
基づいて説明する。図1は本発明の実施の形態に係る油
圧機械の再生回路の回路図である。この図で、図2に示
す部分と同一又は等価な部分には同一符号を付して説明
を省略する。16はシャトル弁11からの出力、即ち、
ボトム側の圧力と切換弁8の出口側の圧力のうち高い方
の圧力を切換弁8のパイロット室83へ導くパイロット
管路である。本実施の形態における再生回路と、図2に
示す再生回路とは、切換弁8のパイロット室83に導入
される圧力が、図2に示す回路では油圧シリンダ2のボ
トム側の圧力であるのに対して、本実施の形態では上述
のようにボトム側の圧力と切換弁8の出口側の圧力のう
ち高い方の圧力である点で異なるのみであり、他の構成
は同じである。
DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the illustrated embodiments. FIG. 1 is a circuit diagram of a regeneration circuit of a hydraulic machine according to an embodiment of the present invention. In this figure, parts that are the same as or equivalent to those shown in FIG. 16 is the output from the shuttle valve 11, that is,
This is a pilot conduit for guiding the higher pressure of the pressure on the bottom side and the pressure on the outlet side of the switching valve 8 to the pilot chamber 83 of the switching valve 8. In the regeneration circuit of the present embodiment and the regeneration circuit shown in FIG. 2, the pressure introduced into the pilot chamber 83 of the switching valve 8 is the pressure on the bottom side of the hydraulic cylinder 2 in the circuit shown in FIG. On the other hand, in the present embodiment, as described above, the difference is only the higher pressure of the pressure on the bottom side and the pressure on the outlet side of the switching valve 8, and the other configurations are the same.

【0021】次ぎに、本実施の形態の動作を説明する。
本実施の形態の動作も、主回路5に上記こもり圧が存在
する場合以外の動作は図2に示す回路の動作と同じであ
るので、ここでは、主回路5に当該こもり圧が存在する
場合の動作についてのみ説明し、他の場合の動作の説明
は省略する。今、油圧シリンダ2が油圧ショベルのアー
ムシリンダであるとし、操作レバー12を矢印X方向に
操作し、流量制御弁3を図示左側位置に切り換えた場
合、油圧シリンダ2は縮み、アームが前方に押し出され
る。このとき、油圧シリンダ2がストロークエンドに到
達すると、油圧ポンプ1の圧力およびロッド側の圧力は
回路の最高圧力まで上昇する。この状態で操作レバー1
2を中立状態に戻すと、流量制御弁3も中立状態に戻る
が、前述のように、ロッド側の主回路5の配管5a、5
bには高圧のこもり圧が残る。
Next, the operation of this embodiment will be described.
The operation of the present embodiment is also the same as the operation of the circuit shown in FIG. 2 except that the above-described muffled pressure is present in the main circuit 5. Only the operation of the above will be described, and the description of the operation in other cases will be omitted. Now, assuming that the hydraulic cylinder 2 is an arm cylinder of a hydraulic excavator and the operating lever 12 is operated in the direction of arrow X to switch the flow control valve 3 to the left position in the drawing, the hydraulic cylinder 2 contracts and the arm is pushed forward. Be done. At this time, when the hydraulic cylinder 2 reaches the stroke end, the pressure of the hydraulic pump 1 and the pressure on the rod side rise to the maximum pressure of the circuit. Operation lever 1 in this state
When 2 is returned to the neutral state, the flow control valve 3 also returns to the neutral state, but as described above, the pipes 5a, 5 of the main circuit 5 on the rod side,
A high muffled pressure remains in b.

【0022】このこもり圧が残っている状態で操作レバ
ー12を矢印Y方向に操作すると、流量制御弁3は図示
右側位置に切り換えられ、配管5a、5bのこもり圧が
一挙にタンクに排出され、こもり圧は瞬時にアームシリ
ンダに作用する通常の負荷圧となる。この場合、操作レ
バー12の操作の初期に、切換弁8のばね81で設定さ
れた圧力以上のこもり圧が存在しているときには、配管
5aに存在する当該こもり圧が、シャトル弁11、パイ
ロット管路16を介して切換弁8のパイロット室83に
導入され、切換弁8は導通側82に切り換えられ、配管
5aと配管5bとを開放状態にする。これにより、切換
弁8の前後差圧は再生弁10のバネ104で設定された
圧力以下となり、再生弁10は閉じ状態に保持され、ロ
ッド側の圧油はボトム側には再生されず、流量制御弁3
を通ってタンクに排出される。
When the operating lever 12 is operated in the direction of the arrow Y while the muffled pressure remains, the flow control valve 3 is switched to the right position in the drawing, and the muffled pressures of the pipes 5a and 5b are discharged to the tank all at once. The muffled pressure instantly becomes a normal load pressure that acts on the arm cylinder. In this case, in the initial stage of the operation of the operation lever 12, when the muffled pressure equal to or higher than the pressure set by the spring 81 of the switching valve 8 exists, the muffled pressure present in the pipe 5a is the shuttle valve 11 and the pilot pipe. It is introduced into the pilot chamber 83 of the switching valve 8 via the passage 16, the switching valve 8 is switched to the conduction side 82, and the pipes 5a and 5b are opened. As a result, the differential pressure across the switching valve 8 becomes equal to or lower than the pressure set by the spring 104 of the regeneration valve 10, the regeneration valve 10 is held in the closed state, and the pressure oil on the rod side is not regenerated on the bottom side, and the flow rate is reduced. Control valve 3
Through to the tank.

【0023】この結果、アームシリンダの速度は、こも
り圧が残っている操作の初期段階では流量制御弁3の絞
り32の絞り量(開口量)、即ち、操作レバー12の操
作量に相当する速度となる。そして、高圧のこもり圧が
低下し、アームシリンダに作用する通常の負荷圧になる
と、切換弁8のパイロット室83に導入される圧力がば
ね84に設定された圧力以下まで低下するので、切換弁
8は図示の固定絞り81側に切り換えられ、主回路5は
固定絞り81が介在する絞り状態になり、操作レバー1
2の操作量によってロッド側の圧油がボトム側に再生さ
れるか否かが決定される通常の動作に戻る。
As a result, the speed of the arm cylinder is equivalent to the throttle amount (opening amount) of the throttle 32 of the flow control valve 3, that is, the operation amount of the operating lever 12 in the initial stage of the operation in which the muffled pressure remains. Becomes Then, when the high-pressure muffled pressure decreases to a normal load pressure that acts on the arm cylinder, the pressure introduced into the pilot chamber 83 of the switching valve 8 decreases to the pressure set in the spring 84 or less, so the switching valve 8 is switched to the side of the fixed diaphragm 81 shown in the figure, and the main circuit 5 is brought into a diaphragm state in which the fixed diaphragm 81 is interposed.
The normal operation in which it is determined whether or not the pressure oil on the rod side is regenerated to the bottom side by the operation amount of 2 is returned to.

【0024】このように、本実施の形態では、ボトム側
の圧力と切換弁8の出口側の圧力のうち高い方の圧力を
パイロット管路16で切換弁8のパイロット室83へ導
くようにしたので、バケットの爪先を水平に引き込む作
業においても、作業開始直後の段階でアームシリンダの
速度が早過ぎてブーム上げのタイミングが遅れるような
ことはなく、精度良く水平にバケット爪先を引き込むこ
とができる。又、アームを単独に振り下ろす操作におい
ても、衝撃が発生することはなく円滑に操作することが
でき、操作性も向上する。
As described above, in the present embodiment, the higher pressure of the pressure on the bottom side and the pressure on the outlet side of the switching valve 8 is guided to the pilot chamber 83 of the switching valve 8 through the pilot pipe 16. Therefore, even in the work of pulling the toes of the bucket horizontally, it is possible to accurately pull the toes of the bucket horizontally without the arm cylinder speed becoming too fast and the boom raising timing being delayed immediately after the start of the work. . Further, even when the arm is independently swung down, no shock is generated and the arm can be smoothly operated, and the operability is improved.

【0025】なお、上記実施の形態の説明では、油圧シ
ョベルのアームおよびアームシリンダを例示して説明し
たが、他の油圧機械の油圧シリンダでも適用可能である
のは明らかである。
In the above description of the embodiment, the arm and the arm cylinder of the hydraulic excavator have been described as an example, but it is obvious that the hydraulic cylinder of another hydraulic machine is also applicable.

【0026】[0026]

【発明の効果】以上述べたように、本発明では、ボトム
側の圧力と切換弁の出口圧力のうち高い方の圧力を再生
弁の室へ導入するようにしたので、管路にこもり圧が存
在しても、ロッド側からボトム側への圧油の再生が阻止
され、こもり圧が残っている場合の作業開始直後におい
ても速度変化の少ない安定した動作を行なうことがで
き、ひいては精度の良い作業を円滑に行なうことができ
る。
As described above, according to the present invention, the higher pressure of the pressure on the bottom side and the outlet pressure of the switching valve is introduced into the chamber of the regenerative valve, so that the withdrawal pressure in the pipeline is reduced. Even if it exists, regeneration of pressure oil from the rod side to the bottom side is blocked, and stable operation with little speed change can be performed even immediately after the start of work when there is a muffled pressure, which in turn is highly accurate. Work can be performed smoothly.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の実施の形態に係る油圧機械の再生回路
の油圧回路図である。
FIG. 1 is a hydraulic circuit diagram of a regeneration circuit of a hydraulic machine according to an embodiment of the present invention.

【図2】従来の油圧機械の再生回路の油圧回路図であ
る。
FIG. 2 is a hydraulic circuit diagram of a regeneration circuit of a conventional hydraulic machine.

【図3】流量制御弁の特性図である。FIG. 3 is a characteristic diagram of a flow control valve.

【符号の説明】[Explanation of symbols]

1 油圧ポンプ 2 油圧シリンダ 3 流量制御弁 4、5 主回路 8 切換弁 10 再生弁 11 シャトル弁 12 操作レバー 16 パイロット管路 81固定絞り 82 導通側 83 パイロット室 84 ばね 1 Hydraulic Pump 2 Hydraulic Cylinder 3 Flow Control Valve 4, 5 Main Circuit 8 Switching Valve 10 Regeneration Valve 11 Shuttle Valve 12 Operating Lever 16 Pilot Pipeline 81 Fixed Throttle 82 Conducting Side 83 Pilot Chamber 84 Spring

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 油圧ポンプと、この油圧ポンプにより駆
動される油圧アクチュエータと、前記油圧ポンプと前記
油圧アクチュエータとの間に介在し当該油圧アクチュエ
ータの駆動を制御する流量制御弁と、前記油圧アクチュ
エータの一方側管路と他方側管路との間の導通、遮断を
行う再生弁と、前記一方側管路と前記流量制御弁との間
に介在するとともに、パイロット室を有しこのパイロッ
ト室に導入される圧力が予め定められた設定値以下であ
るとき前記一方側管路と前記流量制御弁との間の油圧回
路の状態を導通状態から絞り状態へ切り換える切換弁
と、前記他方側管路の圧力と前記切換弁の出口圧力のう
ち高い方の圧力を前記再生弁の室へ導入するパイロット
管路とで構成されている油圧機械の再生回路において、
前記パイロット管路の圧力と同一圧力を前記切換弁の前
記パイロット室へ導入することを特徴とする油圧機械の
再生回路。
1. A hydraulic pump, a hydraulic actuator driven by the hydraulic pump, a flow rate control valve interposed between the hydraulic pump and the hydraulic actuator to control the drive of the hydraulic actuator, and a hydraulic actuator of the hydraulic actuator. A regeneration valve that connects and disconnects between the one-side conduit and the other-side conduit, and is interposed between the one-side conduit and the flow control valve, and has a pilot chamber and is introduced into this pilot chamber. When the pressure to be applied is equal to or lower than a predetermined set value, a switching valve for switching the state of the hydraulic circuit between the one side pipeline and the flow rate control valve from the conduction state to the throttle state, and the other side pipeline In the regeneration circuit of the hydraulic machine, which is constituted by a pilot line for introducing a higher pressure of the pressure and the outlet pressure of the switching valve into the chamber of the regeneration valve,
A regeneration circuit for a hydraulic machine, wherein the same pressure as the pressure in the pilot line is introduced into the pilot chamber of the switching valve.
JP10011796A 1996-04-22 1996-04-22 Regeneration circuit of hydraulic machine Expired - Fee Related JP3457798B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP10011796A JP3457798B2 (en) 1996-04-22 1996-04-22 Regeneration circuit of hydraulic machine

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP10011796A JP3457798B2 (en) 1996-04-22 1996-04-22 Regeneration circuit of hydraulic machine

Publications (2)

Publication Number Publication Date
JPH09287172A true JPH09287172A (en) 1997-11-04
JP3457798B2 JP3457798B2 (en) 2003-10-20

Family

ID=14265420

Family Applications (1)

Application Number Title Priority Date Filing Date
JP10011796A Expired - Fee Related JP3457798B2 (en) 1996-04-22 1996-04-22 Regeneration circuit of hydraulic machine

Country Status (1)

Country Link
JP (1) JP3457798B2 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITMO20100302A1 (en) * 2010-10-29 2012-04-30 Nem S P A OLEO HYDRAULIC ACTUATOR CONTROL SYSTEM FOR HANDLING A LOAD.
WO2015031275A1 (en) * 2013-08-29 2015-03-05 Caterpillar Global Mining Llc Hydraulic control circuit with regeneration valve
CN105692509A (en) * 2015-11-10 2016-06-22 林德(中国)叉车有限公司 Forklift hydraulic system with dynamic throttling speed governing circuit
KR20200098883A (en) * 2019-02-13 2020-08-21 두산인프라코어 주식회사 Construction machinery
CN113685394A (en) * 2021-08-31 2021-11-23 徐州徐工矿业机械有限公司 High-pressure large-flow oil cylinder regeneration hydraulic system of excavator

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ITMO20100302A1 (en) * 2010-10-29 2012-04-30 Nem S P A OLEO HYDRAULIC ACTUATOR CONTROL SYSTEM FOR HANDLING A LOAD.
WO2015031275A1 (en) * 2013-08-29 2015-03-05 Caterpillar Global Mining Llc Hydraulic control circuit with regeneration valve
US9394922B2 (en) 2013-08-29 2016-07-19 Caterpillar Global Mining Llc Hydraulic control circuit with regeneration valve
CN105692509A (en) * 2015-11-10 2016-06-22 林德(中国)叉车有限公司 Forklift hydraulic system with dynamic throttling speed governing circuit
KR20200098883A (en) * 2019-02-13 2020-08-21 두산인프라코어 주식회사 Construction machinery
CN113685394A (en) * 2021-08-31 2021-11-23 徐州徐工矿业机械有限公司 High-pressure large-flow oil cylinder regeneration hydraulic system of excavator

Also Published As

Publication number Publication date
JP3457798B2 (en) 2003-10-20

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