JPS61116202U

JPS61116202U -

Info

Publication number: JPS61116202U
Application number: JP19785084U
Authority: JP
Priority date: 1984-12-29
Filing date: 1984-12-29
Publication date: 1986-07-22
Also published as: JPH0326323Y2

Description

[Brief explanation of the drawing]

第１図はこの考案の第１実施例を示す油圧回路
図、第２図乃至第４図は同じくその方向流量制御
弁の具体的構造例の縦断面と共に示す油圧回路図
で、第２図は中立位置、第３図は小流量制御位置
、第４図は大流量制御位置をそれぞれ示す。第５
図は第１図乃至第４図に示した実施例による油圧
シリンダのスタートから停止までの速度線図とそ
れに対応するポンプ圧力とブレーキ圧力の変化を
示す線図である。第６図は第１図に示す従来例に
よる第５図と同様なシリンダ駆動条件におけるポ
ンプ圧力とブレーキ圧力の変化を示す線図である
。第７図はこの考案の第２実施例を示す油圧回路
図、第８図はこの考案の第３実施例を示す油圧回
路図、第９図はこの考案の第４実施例を示す第２
図と同様な縦断面と共に示す油圧回路図、第１０
図はこの考案の第５実施例を示す油圧回路図であ
る。第１１図は従来の慣性負荷駆動用方向流量制
御装置の例を示す油圧回路図である。１…油圧シリンダ、３…圧力補償弁、６…定吐
出力量ポンプ、１０，１０′，１０″…方向流量
制御弁、１１…ボデイ、１２…スプール、１２ａ
，１２ｂ…テーパランド、２０…パイロツトリリ
ーフ弁、４０…減圧形圧力補償弁、４１…一定油
圧源、５０…圧力調整弁、Ｗ…貫性負荷。 Fig. 1 is a hydraulic circuit diagram showing a first embodiment of this invention, Figs. The neutral position, FIG. 3 shows the small flow rate control position, and FIG. 4 shows the large flow rate control position. Fifth
The figure is a speed diagram from start to stop of the hydraulic cylinder according to the embodiment shown in FIGS. 1 to 4, and a diagram showing the corresponding changes in pump pressure and brake pressure. FIG. 6 is a diagram showing changes in pump pressure and brake pressure under the same cylinder drive conditions as in FIG. 5 according to the conventional example shown in FIG. Fig. 7 is a hydraulic circuit diagram showing a second embodiment of this invention, Fig. 8 is a hydraulic circuit diagram showing a third embodiment of this invention, and Fig. 9 is a hydraulic circuit diagram showing a fourth embodiment of this invention.
Hydraulic circuit diagram shown with a longitudinal section similar to the figure, No. 10
The figure is a hydraulic circuit diagram showing a fifth embodiment of this invention. FIG. 11 is a hydraulic circuit diagram showing an example of a conventional directional flow rate control device for driving an inertial load. DESCRIPTION OF SYMBOLS 1...Hydraulic cylinder, 3...Pressure compensation valve, 6...Constant discharge amount pump, 10, 10', 10''...Directional flow control valve, 11...Body, 12...Spool, 12a
, 12b... Taper land, 20... Pilot relief valve, 40... Pressure reducing type pressure compensation valve, 41... Constant oil pressure source, 50... Pressure regulating valve, W... Penetrating load.

Claims

[Scope of utility model registration request]

A meter-in control type directional flow rate comprising a pressure compensation valve and a directional flow rate control valve, the pressure compensation valve maintaining a constant differential pressure between the pressure oil supply port and the supply side load port of the directional flow rate control valve. In the control device, a throttle surface is formed in a portion of the spool of the directional flow rate control valve that opens and closes the flow path between the discharge side load port and the tank port, and in a small flow area, the opening degree between the discharge side port and the tank port is The opening degree between the pressure oil supply port and the supply side load port is made sufficiently small compared to the opening degree between the pressure oil supply port and the supply side load port, and the vent chamber of the pressure compensation valve or the separately provided pressure adjustment valve is connected to the pilot relief valve and the directional flow rate control valve. A directional flow rate control device for driving an inertial load, wherein the directional flow rate control valve connects to a tank line via a tank line, and in the small flow rate region, the directional flow rate control valve connects the pilot relief valve connection port to the tank port.