JPS6255025B2 - - Google Patents
Info
- Publication number
- JPS6255025B2 JPS6255025B2 JP76981A JP76981A JPS6255025B2 JP S6255025 B2 JPS6255025 B2 JP S6255025B2 JP 76981 A JP76981 A JP 76981A JP 76981 A JP76981 A JP 76981A JP S6255025 B2 JPS6255025 B2 JP S6255025B2
- Authority
- JP
- Japan
- Prior art keywords
- hydraulic
- hydraulic motor
- pressure
- amount
- operating device
- 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.)
- Expired
Links
- 238000006073 displacement reaction Methods 0.000 claims description 14
- 230000001133 acceleration Effects 0.000 description 20
- 230000007423 decrease Effects 0.000 description 9
- 230000007935 neutral effect Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
Landscapes
- Control Of Fluid Gearings (AREA)
Description
【発明の詳細な説明】
この発明は可変容量形油圧ポンプにより油圧モ
ータたとえば油圧シヨベル、油圧クレーンの旋回
油圧モータ等を駆動する油圧閉回路に関するもの
である。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic closed circuit for driving a hydraulic motor, such as a hydraulic excavator, a swing hydraulic motor of a hydraulic crane, etc., using a variable displacement hydraulic pump.
第１図は従来の油圧モータ駆動油圧閉回路を示
す図である。図において１は両傾転可変容量形油
圧ポンプ、２は油圧ポンプ１により駆動される固
定容量形油圧モータ、３は油圧モータ２により駆
動される負荷、４ａ，４ｂは油圧ポンプ１と油圧
モータ２とを接続する管路、５は油圧源、６ａ，
６ｂは油圧源５と管路４ａ，４ｂとを接続する管
路に設けられた逆止弁、７は管路４ａ，４ｂ間に
設けられたフラツシング弁、８ａ，８ｂは管路４
ａ，４ｂ間に設けられた圧力設定弁である。 FIG. 1 is a diagram showing a conventional hydraulic motor drive hydraulic closed circuit. In the figure, 1 is a double tilting variable displacement hydraulic pump, 2 is a fixed displacement hydraulic motor driven by the hydraulic pump 1, 3 is a load driven by the hydraulic motor 2, and 4a and 4b are the hydraulic pump 1 and the hydraulic motor 2. 5 is a hydraulic power source, 6a,
6b is a check valve provided in a pipe connecting the hydraulic power source 5 and pipes 4a and 4b, 7 is a flushing valve provided between pipes 4a and 4b, and 8a and 8b are pipes 4
This is a pressure setting valve provided between a and 4b.
この油圧閉回路においては、操作レバーなどの
操作装置（図示せず）を操作することにより、油
圧ポンプ１の傾転量を零から所定値にすると、た
とえば管路４ａに圧油が吐出され、油圧モータ２
が回転を始め、負荷３が駆動される。このとき、
油圧ポンプ１の吐出量が油圧モータ２の回転速度
に見合つた流量よりも多いと、管路４ａの圧力が
上昇し、管路４ａの圧力が圧力設定弁８ａの設定
圧力に達すると、管路４ａの圧油が圧力設定弁８
ａを通つて管路４ｂへ流出するから、管路４ａの
最高圧力は圧力設定弁８ａの設定圧力となる。こ
のため、油圧モータ２の加速時の回転加速度は、
操作装置の操作量にかかわらず、圧力設定弁８
ａ，８ｂの設定圧力および油圧モータ２の容量で
定まる一定値となる。また、油圧モータ２が回転
しているときに、操作装置を操作することによ
り、油圧ポンプ１の吐出量を減少させると、油圧
モータ２が負荷３の慣性により回転されるため、
油圧モータ２から吐出される油量が油圧ポンプ１
の吐出量（吸入量）より多くなり、管路４ｂの圧
力が上昇し、管路４ｂの圧力が圧力設定弁８ｂの
設定圧力に達すると、管路４ｂの圧油が圧力設定
弁８ｂを通つて管路４ａへ流出するから、管路４
ｂの最高圧力は圧力設定弁の設定圧力となる。こ
のため、油圧モータ２の減速時の回転加速度は、
操作装置の操作量にかかわらず、圧力設定弁８
ｂ，８ａの設定圧力および油圧モータ２の容量で
定まる一定値となる。このように、操作装置の操
作量にかかわらず、油圧モータ２の回転加速度が
一定値であるから、微妙な加減速の制御が困難で
あり、また加速時に油圧ポンプ１の圧油が圧力設
定弁８ａ，８ｂを通過するから、エネルギー損失
が大きい。 In this hydraulic closed circuit, when the amount of tilting of the hydraulic pump 1 is changed from zero to a predetermined value by operating an operating device (not shown) such as an operating lever, pressure oil is discharged into the pipe line 4a, for example. Hydraulic motor 2
starts rotating, and the load 3 is driven. At this time,
When the discharge amount of the hydraulic pump 1 is larger than the flow rate commensurate with the rotational speed of the hydraulic motor 2, the pressure in the pipe line 4a increases, and when the pressure in the pipe line 4a reaches the set pressure of the pressure setting valve 8a, the pressure in the pipe line 4a increases. The pressure oil of 4a is the pressure setting valve 8
Since it flows out to the pipe line 4b through the pipe a, the maximum pressure in the pipe line 4a becomes the set pressure of the pressure setting valve 8a. Therefore, the rotational acceleration of the hydraulic motor 2 during acceleration is:
Regardless of the operating amount of the operating device, the pressure setting valve 8
It is a constant value determined by the set pressures of a and 8b and the capacity of the hydraulic motor 2. Furthermore, if the discharge amount of the hydraulic pump 1 is reduced by operating the operating device while the hydraulic motor 2 is rotating, the hydraulic motor 2 will be rotated by the inertia of the load 3.
The amount of oil discharged from the hydraulic motor 2 is the amount of oil discharged from the hydraulic pump 1.
When the pressure in the pipe 4b increases and the pressure in the pipe 4b reaches the set pressure in the pressure setting valve 8b, the pressure oil in the pipe 4b passes through the pressure setting valve 8b. Since it flows out to the pipe 4a, the pipe 4
The maximum pressure b becomes the set pressure of the pressure setting valve. Therefore, the rotational acceleration of the hydraulic motor 2 during deceleration is
Regardless of the operating amount of the operating device, the pressure setting valve 8
It is a constant value determined by the set pressures of b and 8a and the capacity of the hydraulic motor 2. As described above, since the rotational acceleration of the hydraulic motor 2 is a constant value regardless of the amount of operation of the operating device, it is difficult to control delicate acceleration/deceleration, and the pressure oil of the hydraulic pump 1 is released from the pressure setting valve during acceleration. Since it passes through 8a and 8b, energy loss is large.
この発明は上述の問題点を解決するためになさ
れたもので、油圧モータの回転加速度を操作装置
の操作量に応じた値とすることができ、かつエネ
ルギー損失が小さい油圧モータ駆動油圧閉回路を
提供することを目的とする。 This invention was made in order to solve the above-mentioned problems, and provides a hydraulic motor drive hydraulic closed circuit in which the rotational acceleration of the hydraulic motor can be set to a value corresponding to the operation amount of the operating device, and the energy loss is small. The purpose is to provide.
この目的を達成するため、この発明においては
油圧ポンプの傾転量を制御するためのシリンダ
と、そのシリンダと操作装置との間に設けられた
第１のサーボ弁と、パイロツトポートの圧力が上
記操作装置で設定された圧力以上になつたとき上
記シリンダへの圧油を遮断する第２のサーボ弁
と、上記操作装置が作動位置となつたとき上記第
２のサーボ弁のパイロツトポートに上記油圧ポン
プの圧油が吐出された管路の圧力を供給する切換
弁とを設ける。 In order to achieve this object, the present invention includes a cylinder for controlling the amount of tilting of the hydraulic pump, a first servo valve provided between the cylinder and the operating device, and a pilot port whose pressure is as described above. A second servo valve shuts off the pressure oil to the cylinder when the pressure exceeds the pressure set by the operating device, and the hydraulic pressure is supplied to the pilot port of the second servo valve when the operating device is in the operating position. A switching valve is provided to supply the pressure of the pipe from which the pressure oil of the pump is discharged.
第２図はこの発明に係る油圧モータ駆動油圧閉
回路を示す図である。図において９は油圧ポンプ
１の傾転量を制御するシリンダ、１０はシリンダ
９のピストン、１１ａ，１１ｂはシリンダ９のス
プリング、１２は操作装置である操作レバーで、
図面の都合上同一の操作レバー１２を４つに示し
てある。１３は操作レバー１２とシリンダ９との
間に設けられたサーボ弁、１４はサーボ弁１３の
スリーブで、スリーブ１４は操作レバー１２の操
作量に応じて変位する。１５はサーボ弁１３のス
プールで、スプール１５はピストン１０と連動し
て変位する。１６は油圧源、１７は油圧源１６と
ホーボ弁１３との間に設けられたサーボ弁、１８
はサーボ弁１７のスリーブ、１９はスリーブ１８
の一端に設けられたスプリング、２０はスリーブ
１８の他端に取付けられたコ形部材、２１は操作
レバー１２によつて回動されるリンクで、コ形部
材２０はスプリング１９によつてリンク２１に押
付けられているから、スリーブ１８は操作レバー
１２の操作量の絶対値に応じた値だけ変位する。
２２はサーボ弁１７のスプール、２３はスプール
２２の一端に設けられたスプリング、２４は操作
レバー１２により操作される切換弁で、切換弁２
４がＮ位置のときにはサーボ弁１７のパイロツト
ポートをタンクに連通し、切換弁２４がＡ，Ｂ位
置のときにはサーボ弁１７のパイロツトポートを
管路４ａ，４ｂに連通する。２５は操作レバー１
２により移動されるカム、２６ａ，２６ｂはカム
２５の位置により設定圧力が変化する圧力設定弁
で、圧力設定弁２６ａ，２６ｂの設定圧力が変化
すると、圧力設定弁８ａ，８ｂの設定圧力が変化
する。 FIG. 2 is a diagram showing a hydraulic motor drive hydraulic closed circuit according to the present invention. In the figure, 9 is a cylinder that controls the amount of tilting of the hydraulic pump 1, 10 is a piston of the cylinder 9, 11a and 11b are springs of the cylinder 9, and 12 is an operating lever that is an operating device.
For convenience of drawing, four identical operating levers 12 are shown. 13 is a servo valve provided between the operating lever 12 and the cylinder 9; 14 is a sleeve of the servo valve 13; the sleeve 14 is displaced according to the amount of operation of the operating lever 12; 15 is a spool of the servo valve 13, and the spool 15 is displaced in conjunction with the piston 10. 16 is a hydraulic source, 17 is a servo valve provided between the hydraulic source 16 and the hobo valve 13, 18
19 is the sleeve of the servo valve 17, and 19 is the sleeve 18.
20 is a U-shaped member attached to the other end of the sleeve 18; 21 is a link rotated by the operating lever 12; , the sleeve 18 is displaced by a value corresponding to the absolute value of the operating amount of the operating lever 12.
22 is a spool of the servo valve 17; 23 is a spring provided at one end of the spool 22; 24 is a switching valve operated by the operating lever 12;
When the switching valve 4 is in the N position, the pilot port of the servo valve 17 is communicated with the tank, and when the switching valve 24 is in the A and B positions, the pilot port of the servo valve 17 is communicated with the pipes 4a and 4b. 25 is operation lever 1
The cams 26a and 26b moved by the cams 26a and 26b are pressure setting valves whose set pressures change depending on the position of the cam 25. When the set pressures of the pressure setting valves 26a and 26b change, the set pressures of the pressure setting valves 8a and 8b change. do.
この油圧閉回路においては、操作レバー１２が
図のように中立位置にあるときには、シリンダ９
のピストン１０が中立位置にあり、油圧ポンプ１
の傾転量は零であるから、油圧ポンプ１は圧油を
吐出せず、油圧モータ２が停止している。この状
態で、操作レバー１２をたとえば右方向に傾す
と、スリーブ１４が右方に移動するから、サーボ
弁１３がＢ位置となり、スリーブ１８が左方に移
動するから、サーボ弁１７はＡ位置になり、また
切換弁２４がＡ位置となり、さらにカム２５が右
方に移動するから、圧力設定弁２６ａの設定圧力
は変化しないので、圧力設定弁８ａの設定圧力は
変化せず、一方圧力設定弁２６ｂの設定圧力が減
少するので、圧力設定弁８ｂの設定圧力が減少す
る。このため、油圧源１６の圧油がサーボ弁１
７，１３を介してシリンダ９の左室９ａに供給さ
れ、シリンダ９の右室９ｂがサーボ弁１３を介し
てタンクに連通するから、ピストン１０が右方に
移動し、油圧ポンプ１の傾転量が増加し、油圧ポ
ンプ１の圧油が管路４ａに吐出され、油圧モータ
２が回転し始め、負荷３が駆動される。このと
き、負荷３の慣性が大きいため、油圧モータ２の
回転速度がゆつくり上昇し、油圧ポンプ１の吐出
量が油圧モータ２の回転に見合つた流量よりも多
いと、管路４ａの圧力が上昇する。そして、管路
４ａの圧力は切換弁２４を介してサーボ弁１７の
パイロツトポートに供給されるから、スプール２
２が左方に移動し、管路４ａの圧力がスリーブ１
８の変位量（操作レバー１２の操作量）に応じた
値になると、サーボ弁１７がＢ位置となり、左室
９ａがサーボ弁１３，１７を介してタンクに連通
し、ピストン１０が左方に移動し、油圧ポンプ１
の傾転量が減少し、油圧ポンプ１の吐出量が減少
する。この結果、管路４ａの圧力が減少し、スプ
ール２２が右方に移動し、サーボ弁１７がＮ位置
となり、左室９ａに油圧源１６の圧油が供給さ
れ、ピストン１０が右方に移動し、油圧ポンプ１
の傾転量が増加する。そして、再び油圧ポンプ１
の吐出量が油圧モータ２の回転速度に見合つた流
量よりも多くなると、管路４ａの圧力が上昇し、
サーボ弁１７により油圧源１６の圧油が遮断され
る。このようにして、油圧ポンプ１の吐出量は油
圧モータ２の回転速度に応じて除々に増加し、ピ
ストン１０の変位量（スプール１５の変位量）が
スリーブ１４の変位量（操作レバー１２の操作
量）に応じた値になると、サーボ弁１３がＮ位置
となり、シリンダ９の左室９ａ、右室９ｂがブロ
ツクされるから、油圧ポンプ１の吐出量は操作レ
バー１２の操作量に応じた値（定常吐出量）に保
持され、油圧モータ２の回転速度が操作レバー１
２の操作量に応じた値である定常回転速度にな
る。すなわち、油圧ポンプ１の定常吐出量Ｑ（油
圧モータ２の定常回転速度）は第３図ａに示すよ
うに操作レバー１２の操作量ｘに応じた値とな
る。ここで、操作レバー１２の操作量の絶対値を
大きくした場合には、スリーブ１８の変位量が大
きいから、サーボ弁１７のパイロツトポートに作
用する圧力すなわち油圧ポンプ１の吐出側管路の
圧力が高くなければ、サーボ弁１７がＢ位置にな
らないのに対して、操作レバー１２の操作量の絶
対値を小さくした場合には、スリーブ１８の変位
量が小さいから、油圧ポンプ１の吐出側管路の圧
力が低くとも、サーボ弁１７がＢ位置になる。す
なわち、サーボ弁１７がＢ位置となり、油圧源１
６の圧油を遮断するときの油圧ポンプ１の吐出側
管路の圧力P1は、第３図ｂに示すように、操作レ
バー１２の操作量ｘに応じた値となる。したがつ
て、操作レバー１２の操作量の絶対値が大きい場
合には、油圧ポンプ１の吐出側管路の圧力が高く
なるから、油圧モータ２の回転加速度が大きくな
り、操作レバー１２の操作量の絶対値が小さい場
合には、油圧ポンプ１の吐出側管路の圧力が低く
なるから、油圧モータ２の回転加速度が小さくな
る。つまり、油圧モータ２の回転加速度は操作レ
バー１２の操作量に応じた値となる。なお、第３
図ｅは操作レバー１２の操作量ｘと切換弁２４の
切換位置との関係を示すグラフである。 In this hydraulic closed circuit, when the operating lever 12 is in the neutral position as shown in the figure, the cylinder 9
The piston 10 of is in the neutral position, and the hydraulic pump 1
Since the amount of tilting is zero, the hydraulic pump 1 does not discharge pressure oil and the hydraulic motor 2 is stopped. In this state, when the operating lever 12 is tilted, for example, to the right, the sleeve 14 moves to the right, which moves the servo valve 13 to the B position, and the sleeve 18 moves to the left, which moves the servo valve 17 to the A position. , the switching valve 24 becomes the A position, and the cam 25 further moves to the right, so the set pressure of the pressure setting valve 26a does not change, so the set pressure of the pressure setting valve 8a does not change, and the one pressure setting Since the set pressure of the valve 26b decreases, the set pressure of the pressure setting valve 8b decreases. Therefore, the pressure oil from the hydraulic source 16 is applied to the servo valve 1.
7 and 13 to the left chamber 9a of the cylinder 9, and the right chamber 9b of the cylinder 9 communicates with the tank via the servo valve 13, so the piston 10 moves to the right, causing the hydraulic pump 1 to tilt. The amount increases, pressure oil from the hydraulic pump 1 is discharged to the pipe line 4a, the hydraulic motor 2 begins to rotate, and the load 3 is driven. At this time, since the inertia of the load 3 is large, the rotational speed of the hydraulic motor 2 increases slowly, and if the discharge amount of the hydraulic pump 1 is greater than the flow rate commensurate with the rotation of the hydraulic motor 2, the pressure in the pipe line 4a increases. Rise. Since the pressure in the pipe line 4a is supplied to the pilot port of the servo valve 17 via the switching valve 24, the spool 2
2 moves to the left, and the pressure in the pipe line 4a increases to the sleeve 1.
8, the servo valve 17 becomes the B position, the left chamber 9a communicates with the tank via the servo valves 13 and 17, and the piston 10 moves to the left. Move and hydraulic pump 1
The amount of tilting of the hydraulic pump 1 decreases, and the discharge amount of the hydraulic pump 1 decreases. As a result, the pressure in the pipe line 4a decreases, the spool 22 moves to the right, the servo valve 17 becomes the N position, pressure oil from the hydraulic source 16 is supplied to the left chamber 9a, and the piston 10 moves to the right. and hydraulic pump 1
The amount of tilting increases. And again hydraulic pump 1
When the discharge amount becomes larger than the flow rate commensurate with the rotational speed of the hydraulic motor 2, the pressure in the pipe line 4a increases,
The servo valve 17 shuts off the pressure oil from the oil pressure source 16 . In this way, the discharge amount of the hydraulic pump 1 gradually increases according to the rotational speed of the hydraulic motor 2, and the amount of displacement of the piston 10 (the amount of displacement of the spool 15) changes from the amount of displacement of the sleeve 14 (the amount of displacement of the operating lever 12). When the servo valve 13 reaches the N position and the left chamber 9a and right chamber 9b of the cylinder 9 are blocked, the discharge amount of the hydraulic pump 1 becomes a value corresponding to the operation amount of the operating lever 12. (steady discharge amount), and the rotation speed of the hydraulic motor 2 is adjusted to the operating lever 1.
The rotational speed becomes a steady rotation speed, which is a value corresponding to the manipulated variable No.2. That is, the steady discharge amount Q of the hydraulic pump 1 (the steady rotational speed of the hydraulic motor 2) has a value corresponding to the manipulated variable x of the operating lever 12, as shown in FIG. 3a. Here, when the absolute value of the operating amount of the operating lever 12 is increased, since the amount of displacement of the sleeve 18 is large, the pressure acting on the pilot port of the servo valve 17, that is, the pressure of the discharge side pipe of the hydraulic pump 1, is increased. If it is not high, the servo valve 17 will not be in the B position, whereas if the absolute value of the operating amount of the operating lever 12 is small, the displacement amount of the sleeve 18 is small, so the discharge side pipe of the hydraulic pump 1 Even if the pressure is low, the servo valve 17 is in the B position. That is, the servo valve 17 is in the B position, and the hydraulic power source 1
The pressure P1 in the discharge side conduit of the hydraulic pump 1 when the pressure oil 6 is cut off has a value corresponding to the operating amount x of the operating lever 12, as shown in FIG. 3b. Therefore, when the absolute value of the operating amount of the operating lever 12 is large, the pressure in the discharge side pipe of the hydraulic pump 1 increases, the rotational acceleration of the hydraulic motor 2 increases, and the operating amount of the operating lever 12 increases. When the absolute value of is small, the pressure in the discharge side pipe of the hydraulic pump 1 becomes low, and therefore the rotational acceleration of the hydraulic motor 2 becomes small. In other words, the rotational acceleration of the hydraulic motor 2 has a value corresponding to the amount of operation of the operating lever 12. In addition, the third
FIG. e is a graph showing the relationship between the operating amount x of the operating lever 12 and the switching position of the switching valve 24.
つぎに、油圧モータ２が定常回転速度で回転し
ているときに、操作レバー１２を中立位置にする
と、スリーブ１４が図示の位置に戻るから、サー
ボ弁１３がＡ位置となり、またスリーブ１８が図
示の位置に戻り、かつ切換弁２４がＮ位置に戻る
ので、サーボ弁１７のパイロツトポートがタンク
に連通するから、サーボ弁１７はＮ位置となり、
さらにカム２５の変位が零となるから、圧力設定
弁２６ａ，２６ｂの設定圧力が最高値であり、圧
力設定弁８ａ，８ｂの設定圧力が最高値となる。
このため、油圧源１６の圧油がサーボ弁１７，１
３を介してシリンダ９の右室９ｂに供給され、左
室９ａがサーボ弁１３を介してタンクに連通する
から、ピストン１０が左方に移動し、油圧ポンプ
１の傾転量が減少し、ピストン１０が中立位置と
なつたとき、すなわち油圧ポンプ１の傾転量が零
となり、油圧ポンプ１の吐出量が零となつたと
き、スプール１５が図示の位置に戻り、サーボ弁
１３はＮ位置となり、左室９ａ、右室９ｂがブロ
ツクされるので、ピストン１０が中立位置に保持
され、油圧ポンプ１の傾転量が零に保持される。
このとき、油圧モータ２は負荷３の慣性力により
回転し続けるので、管路４ｂの圧力が高くなり、
圧力設定弁８ｂが開となり、管路４ｂの圧油が圧
力設定弁８ｂを介して管路４ａに流出し、油圧モ
ータ２の回転速度がしだいに小さくなり、油圧モ
ータ２が停止する。また、油圧モータ２が定常回
転速度で回転しているときに、操作レバー１２の
操作量を小さくすると、操作レバー１２を中立位
置に戻したときとほぼ同等の作用により、ピスト
ン１０の変位量が操作レバー１２の操作量に応じ
た値に保持され、油圧ポンプ１の吐出量が操作レ
バー１２の操作量に応じた値に減少する。このと
き、油圧ポンプ１の吐出量（吸入量）が油圧モー
タ２の回転速度に見合つた流量よりも少ないと、
管路４ｂの圧力が上昇し、管路４ｂの圧力が圧力
設定弁８ｂの設定圧力になると、管路４ｂの圧油
が圧力設定弁８ｂを介して管路４ａに流出し、油
圧モータ２の回転速度がしだいに小さくなる。そ
して、油圧モータ２の回転速度が油圧ポンプ１の
吐出量に見合つた値に近づくと、管路４ｂの圧力
が低下し、管路４ｂの圧力が圧力設定弁８ｂの設
定圧力以下になると、圧力設定弁８ｂが閉とな
り、油圧モータ２の回転速度は油圧ポンプ１の吐
出量（操作レバー１２の操作量）に応じた値すな
わち定常回転速度に保持される。ここで、圧力設
定弁２６ａ，２６ｂの設定圧力はカム２５により
操作レバー１２の操作量に応じた値となるので、
圧力設定弁８ａ，８ｂの設定圧力が操作レバー１
２の操作量に応じた値となるから、操作レバー１
２の操作量ｘと管路４ａ，４ｂの最高圧力Ｐ2a，
Ｐ2bとの関係は第３図ｃ，ｄに示すようになる。
このため、油圧モータ２を減速する場合、操作レ
バー１２の操作量を小さくした結果の油圧ポンプ
１の吐出量および吸込量が少ないときには、油圧
ポンプ１の吸入側の管路の圧力が高くなるから、
油圧モータ２の回転加速度（回転減速度）が大き
くなり、操作レバー１２の操作量を小さくした結
果の油圧ポンプ１の吐出量および吸込量がまた大
きいときには、油圧ポンプ１の吸入側の管路の圧
力が低くなるから、油圧モータ２の回転加速度が
小さくなる。つまり、油圧モータ２の回転加速度
は、操作レバー１２の操作量を小さくした結果の
油圧ポンプ１の吐出量および吸込量に応じた値と
なる。 Next, when the hydraulic motor 2 is rotating at a steady rotational speed, when the operating lever 12 is set to the neutral position, the sleeve 14 returns to the position shown in the figure, so the servo valve 13 goes to the A position, and the sleeve 18 moves to the position shown in the figure. Since the switching valve 24 returns to the N position and the pilot port of the servo valve 17 communicates with the tank, the servo valve 17 becomes the N position.
Further, since the displacement of the cam 25 becomes zero, the set pressures of the pressure setting valves 26a and 26b are at the maximum value, and the set pressures of the pressure setting valves 8a and 8b are at the maximum value.
Therefore, the pressure oil of the hydraulic source 16 is
3 to the right chamber 9b of the cylinder 9, and the left chamber 9a communicates with the tank via the servo valve 13, so the piston 10 moves to the left and the amount of tilting of the hydraulic pump 1 decreases. When the piston 10 reaches the neutral position, that is, when the tilting amount of the hydraulic pump 1 becomes zero and the discharge amount of the hydraulic pump 1 becomes zero, the spool 15 returns to the illustrated position and the servo valve 13 returns to the N position. Since the left chamber 9a and the right chamber 9b are blocked, the piston 10 is held at the neutral position and the amount of tilting of the hydraulic pump 1 is held at zero.
At this time, the hydraulic motor 2 continues to rotate due to the inertial force of the load 3, so the pressure in the pipe line 4b increases,
The pressure setting valve 8b is opened, the pressure oil in the conduit 4b flows out into the conduit 4a via the pressure setting valve 8b, the rotational speed of the hydraulic motor 2 gradually decreases, and the hydraulic motor 2 stops. Furthermore, when the amount of operation of the operating lever 12 is reduced while the hydraulic motor 2 is rotating at a steady rotational speed, the amount of displacement of the piston 10 is reduced due to an effect almost the same as when the operating lever 12 is returned to the neutral position. The discharge amount of the hydraulic pump 1 is maintained at a value corresponding to the amount of operation of the operation lever 12, and the discharge amount of the hydraulic pump 1 is reduced to a value corresponding to the amount of operation of the operation lever 12. At this time, if the discharge amount (suction amount) of the hydraulic pump 1 is smaller than the flow rate commensurate with the rotational speed of the hydraulic motor 2,
When the pressure in the pipe line 4b increases and the pressure in the pipe line 4b reaches the set pressure of the pressure setting valve 8b, the pressure oil in the pipe line 4b flows out into the pipe line 4a via the pressure setting valve 8b, and the pressure in the hydraulic motor 2 is increased. The rotation speed gradually decreases. When the rotational speed of the hydraulic motor 2 approaches a value commensurate with the discharge amount of the hydraulic pump 1, the pressure in the pipe line 4b decreases, and when the pressure in the pipe line 4b becomes lower than the set pressure of the pressure setting valve 8b, the pressure The setting valve 8b is closed, and the rotational speed of the hydraulic motor 2 is maintained at a value corresponding to the discharge amount of the hydraulic pump 1 (the amount of operation of the operating lever 12), that is, at a steady rotational speed. Here, the set pressure of the pressure setting valves 26a and 26b is set to a value according to the amount of operation of the operating lever 12 by the cam 25, so
The set pressure of the pressure setting valves 8a and 8b is set to the operating lever 1.
Since the value corresponds to the amount of operation of operation lever 1,
2 operation amount x and the maximum pressure P 2a of the pipes 4a and 4b,
The relationship with P 2b is as shown in Figure 3c and d.
Therefore, when decelerating the hydraulic motor 2, when the discharge amount and suction amount of the hydraulic pump 1 are small as a result of reducing the amount of operation of the operating lever 12, the pressure in the pipeline on the suction side of the hydraulic pump 1 increases. ,
When the rotational acceleration (rotational deceleration) of the hydraulic motor 2 becomes large and the discharge amount and suction amount of the hydraulic pump 1 are also large as a result of reducing the amount of operation of the operating lever 12, the suction side pipe line of the hydraulic pump 1 increases. Since the pressure becomes lower, the rotational acceleration of the hydraulic motor 2 becomes smaller. That is, the rotational acceleration of the hydraulic motor 2 has a value corresponding to the discharge amount and suction amount of the hydraulic pump 1 as a result of reducing the amount of operation of the operating lever 12.
以上の作用をまとめると、油圧モータ２を加減
速するときの回転加速度および定常回転速度は操
作レバー１２の操作量に応じた値となる。このた
め、第４図に示すように、油圧モータ２の回転開
始時から油圧モータ２の回転速度ωが定常回転速
度になるまでの所要時間T1、油圧モータ２の回
転速度ωが最高値ωnaxのときに、油圧モータ２
の減速開始時から油圧モータ２の回転速度ωが定
常回転速度になるまでの所要時間T2を、操作レ
バー１２の操作量にかかわらず、すなわち油圧モ
ータ２の定常回転数にかかわらず一定にすること
もできる。また、第５図に示すように、油圧モー
タ２の回転開始時から油圧モータ２の回転速度ω
が定常回転速度になるまでの総回転数（∫ｔ２ ｔ１ωdt
＝N1）、油圧モータ２の回転速度ωが最高値ωnax
のときに、油圧モータ２の減速開始時から油圧モ
ータ２の回転速度ωが定常回転数になるまでの総
回転数（∫ｔ４ ｔ３ωdt＝N2）を、操作レバー１２の操
作量にかかわらず、すなわち油圧モータ２の定常
回転数にかかわらず一定にすることもできる。さ
らに、加速時に所要時間T1を一定とし、減速時
に総回転数N2を一定にすることもでき、加速時
に総回転数N1を一定にし、減速時に所要時間T2
を一定にすることも可能である。 To summarize the above actions, the rotational acceleration and steady rotational speed when accelerating or decelerating the hydraulic motor 2 have values that correspond to the operation amount of the operation lever 12. Therefore, as shown in FIG. 4, during the time T 1 required from the start of rotation of the hydraulic motor 2 until the rotational speed ω of the hydraulic motor 2 reaches a steady rotational speed, the rotational speed ω of the hydraulic motor 2 reaches the maximum value ω. When nax , hydraulic motor 2
The time T 2 required from the start of deceleration until the rotational speed ω of the hydraulic motor 2 reaches a steady rotational speed is made constant regardless of the operating amount of the operating lever 12, that is, regardless of the steady rotational speed of the hydraulic motor 2. You can also do that. Further, as shown in FIG. 5, the rotational speed ω of the hydraulic motor 2 from the time when the hydraulic motor 2 starts rotating.
The total number of rotations until it reaches a steady rotational speed (∫ t2 t1 ωdt
= N 1 ), the rotational speed ω of the hydraulic motor 2 is the maximum value ω nax
When , the total number of rotations (∫ t4 t3 ωdt=N 2 ) from the start of deceleration of the hydraulic motor 2 until the rotation speed ω of the hydraulic motor 2 reaches a steady rotation number is determined regardless of the operation amount of the operating lever 12. In other words, it can be kept constant regardless of the steady rotation speed of the hydraulic motor 2. Furthermore, it is also possible to keep the required time T 1 constant during acceleration and the total rotation speed N 2 constant during deceleration, or to keep the total rotation speed N 1 constant during acceleration and the required time T 2 during deceleration.
It is also possible to keep constant.
以上説明したように、この発明に係る油圧モー
タ駆動油圧閉回路においては、油圧モータの回転
加速度を操作装置の操作量に応じた値とすること
ができるから、微妙な加減速の制御を容易に行な
うことができる。また、加速時に油圧ポンプの圧
油が圧力設定弁を通過して吸入側管路に流出する
ことがないから、エネルギー損失が小さい。さら
に、速度制御、位置制御等の制候目的に応じて、
加減速時の所要時間、総回転数を一定に定めれ
ば、誰にでも精度のよい操作が非常に簡単にでき
る。このように、この発明の効果は顕著である。 As explained above, in the hydraulic motor drive hydraulic closed circuit according to the present invention, the rotational acceleration of the hydraulic motor can be set to a value corresponding to the operation amount of the operating device, so delicate acceleration/deceleration control can be easily performed. can be done. Moreover, since the pressure oil of the hydraulic pump does not pass through the pressure setting valve and flow out into the suction side pipe during acceleration, energy loss is small. Furthermore, depending on the weather control purpose such as speed control and position control,
If the time required for acceleration/deceleration and the total number of rotations are set constant, anyone can perform precise operations very easily. As described above, the effects of this invention are remarkable.
第１図は従来の油圧モータ駆動油圧閉回路を示
す図、第２図はこの発明に係る油圧モータ駆動油
圧閉回路を示す図、第３図ないし第５図はこの発
明に係る油圧モータ駆動油圧閉回路の動作を説明
するためのグラフである。
１……両傾転可変容量形油圧ポンプ、２……固
定容量形油圧モータ、３……負荷、４ａ，４ｂ…
…管路、８ａ，８ｂ……圧力設定弁、９……シリ
ンダ、１２……操作レバー、１３……サーボ弁、
１６……油圧源、１７……サーボ弁、２４……切
換弁、２５……カム、２６ａ，２６ｂ……圧力設
定弁。
FIG. 1 is a diagram showing a conventional hydraulic motor drive hydraulic closed circuit, FIG. 2 is a diagram showing a hydraulic motor drive hydraulic closed circuit according to the present invention, and FIGS. 3 to 5 are diagrams showing a hydraulic motor drive hydraulic closed circuit according to the present invention. It is a graph for explaining the operation of a closed circuit. 1... Double tilting variable displacement hydraulic pump, 2... Fixed displacement hydraulic motor, 3... Load, 4a, 4b...
... Pipeline, 8a, 8b ... Pressure setting valve, 9 ... Cylinder, 12 ... Operation lever, 13 ... Servo valve,
16... Hydraulic source, 17... Servo valve, 24... Switching valve, 25... Cam, 26a, 26b... Pressure setting valve.
Claims (1)
動する油圧閉回路において、上記油圧ポンプの傾
転量を制御するためのシリンダと、そのシリンダ
と操作装置との間に設けられた第１のサーボ弁
と、パイロツトポートの圧力が上記操作装置で設
定された圧力以上になつたとき上記シリンダへの
圧油を遮断する第２のサーボ弁と、上記操作装置
が作動位置となつたとき上記第２のサーボ弁のパ
イロツトポートに上記油圧ポンプの圧油が吐出さ
れた管路の圧力を供給する切換弁とを具備したこ
とを特徴とする油圧モータ駆動油圧閉回路。 ２ 上記操作装置の操作量にかかわらず、上記油
圧モータを定常回転速度まで加速するのに要する
所要時間をほぼ一定にしたことを特徴とする特許
請求の範囲第１項記載の油圧モータ駆動油圧閉回
路。 ３ 上記操作装置の操作量にかかわらず、上記油
圧モータを定常回転速度まで加速する間の総回転
数をほぼ一定にしたことを特徴とする特許請求の
範囲第１項記載の油圧モータ駆動油圧閉回路。 ４ 上記油圧ポンプと上記油圧モータとを接続す
る管路の最高圧力を設定する圧力設定弁の設定圧
力を上記操作装置の操作量に応じた値とする手段
を具備することを特徴とする特許請求の範囲第１
項、第２項または第３項記載の油圧モータ駆動油
圧閉回路。 ５ 上記操作装置の操作量にかかわらず、上記油
圧モータを定常回転速度まで減速するのに要する
所要時間をほぼ一定にしたことを特徴とする特許
請求の範囲第４項記載の油圧モータ駆動油圧閉回
路。 ６ 上記操作装置の操作量にかかわらず、上記油
圧モータを定常回転速度まで減速する間の総回転
数をほぼ一定にしたことを特徴とする特許請求の
範囲第４項記載の油圧モータ駆動油圧閉回路。[Scope of Claims] 1. In a hydraulic closed circuit in which a hydraulic motor is driven by a variable displacement hydraulic pump, a cylinder for controlling the amount of tilting of the hydraulic pump, and a cylinder provided between the cylinder and an operating device. A first servo valve, a second servo valve that shuts off pressure oil to the cylinder when the pressure in the pilot port exceeds the pressure set by the operating device, and a second servo valve that shuts off pressure oil to the cylinder when the operating device is in the operating position. A hydraulic closed circuit driven by a hydraulic motor, comprising: a switching valve for supplying pressure of a conduit through which pressure oil from the hydraulic pump is discharged to a pilot port of the second servo valve. 2. The hydraulic motor-driven hydraulic closing device according to claim 1, wherein the time required to accelerate the hydraulic motor to a steady rotational speed is substantially constant regardless of the amount of operation of the operating device. circuit. 3. The hydraulic motor-driven hydraulic closing device according to claim 1, wherein the total number of rotations while accelerating the hydraulic motor to a steady rotational speed is kept approximately constant regardless of the amount of operation of the operating device. circuit. 4. A patent claim characterized by comprising means for setting the set pressure of a pressure setting valve that sets the maximum pressure of a conduit connecting the hydraulic pump and the hydraulic motor to a value corresponding to the operating amount of the operating device. range 1
The hydraulic motor drive hydraulic closed circuit according to item 1, 2 or 3. 5. The hydraulic motor-driven hydraulic closing device according to claim 4, wherein the time required to decelerate the hydraulic motor to a steady rotational speed is substantially constant regardless of the amount of operation of the operating device. circuit. 6. The hydraulic motor drive hydraulic closing device according to claim 4, wherein the total number of rotations during deceleration of the hydraulic motor to a steady rotational speed is kept approximately constant regardless of the amount of operation of the operating device. circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP76981A JPS57116969A (en) | 1981-01-08 | 1981-01-08 | Oil pressure closed circuit driven by hydraulic motor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP76981A JPS57116969A (en) | 1981-01-08 | 1981-01-08 | Oil pressure closed circuit driven by hydraulic motor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57116969A JPS57116969A (en) | 1982-07-21 |
| JPS6255025B2 true JPS6255025B2 (en) | 1987-11-18 |
Family
ID=11482895
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP76981A Granted JPS57116969A (en) | 1981-01-08 | 1981-01-08 | Oil pressure closed circuit driven by hydraulic motor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57116969A (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2669459B2 (en) * | 1985-06-15 | 1997-10-27 | 日立建機株式会社 | Control method of hydraulic drive device |
| JP2711894B2 (en) * | 1989-04-28 | 1998-02-10 | 株式会社小松製作所 | Variable displacement pump controller for hydraulically driven vehicles |
| JP5978495B2 (en) * | 2012-09-27 | 2016-08-24 | ダイハツ工業株式会社 | Hydraulic continuously variable transmission |
-
1981
- 1981-01-08 JP JP76981A patent/JPS57116969A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57116969A (en) | 1982-07-21 |
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