JPS6420504U - - Google Patents
Info
- Publication number
- JPS6420504U JPS6420504U JP11550287U JP11550287U JPS6420504U JP S6420504 U JPS6420504 U JP S6420504U JP 11550287 U JP11550287 U JP 11550287U JP 11550287 U JP11550287 U JP 11550287U JP S6420504 U JPS6420504 U JP S6420504U
- Authority
- JP
- Japan
- Prior art keywords
- valve
- directional
- counterbalance
- pilot
- opening area
- 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.)
- Pending
Links
- 238000010276 construction Methods 0.000 claims 2
- 238000010586 diagram Methods 0.000 description 3
Landscapes
- Operation Control Of Excavators (AREA)
- Control And Safety Of Cranes (AREA)
- Fluid-Pressure Circuits (AREA)
Description
第１図は、本考案の実施例を示す回路図、第２
図は、方向切換弁の開口面積とパイロツト圧力と
の特性曲線図、第３図は、従来逆止弁の回路図。
１…ポンプ、２…タンク、３…パイロツト操作
型の方向切換弁、４…シリンダ、５…パイロツト
弁、１０…カウンタバランス弁、１１…制御部、
１２…逆止弁部、１３…操作装置。
Fig. 1 is a circuit diagram showing an embodiment of the present invention;
The figure is a characteristic curve diagram of the opening area of a directional control valve and the pilot pressure, and FIG. 3 is a circuit diagram of a conventional check valve. DESCRIPTION OF SYMBOLS 1...Pump, 2...Tank, 3...Pilot operated directional valve, 4...Cylinder, 5...Pilot valve, 10...Counter balance valve, 11...Control unit,
12... Check valve section, 13... Operating device.
Claims (1)
制御弁と逆止弁を有するカウンタバランス弁を介
して油圧シリンダを接続し、油圧シリンダの一方
の油圧室の圧油の排出を制御する、建設機械の油
圧回路において、前記カウンタバランス弁の制御
部の最大開口面積を、前記方向切換弁の流量制御
領域における最大開口面積以上にし、その逆止弁
を開放させる操作装置を設けると共に、前記方向
切換弁をパイロツト操作型にし、この方向切換弁
と前記カウンタバランス弁の操作装置の双方の１
つのパイロツト弁の出力部に接続し、前記パイロ
ツト弁のパイロツト油圧が、前記方向切換弁流量
制御領域の最大の開口面積に操作する値に達した
とき、その油圧で、前記操作装置が逆止弁を開放
するように、方向切換弁とカウンタバランス弁の
操作部とを連動させた事を特徴とする建設機械の
油圧回路。 A construction machine in which a hydraulic cylinder is connected to a directional switching valve connecting a hydraulic pump and a tank via a counterbalance valve having a control valve and a check valve, and the discharge of pressure oil from one hydraulic chamber of the hydraulic cylinder is controlled. In the hydraulic circuit, the maximum opening area of the control section of the counterbalance valve is set to be equal to or larger than the maximum opening area in the flow rate control region of the directional switching valve, and an operating device is provided to open the check valve, and the directional switching valve is a pilot-operated type, and one of the operating devices for both the directional control valve and the counterbalance valve is
When the pilot oil pressure of the pilot valve reaches a value that operates the maximum opening area of the directional valve flow control region, the operating device operates the check valve with that oil pressure. A hydraulic circuit for construction machinery, characterized in that a directional control valve and a counterbalance valve operating section are linked to open the directional control valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11550287U JPS6420504U (en) | 1987-07-28 | 1987-07-28 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP11550287U JPS6420504U (en) | 1987-07-28 | 1987-07-28 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6420504U true JPS6420504U (en) | 1989-02-01 |
Family
ID=31357218
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP11550287U Pending JPS6420504U (en) | 1987-07-28 | 1987-07-28 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6420504U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6293521U (en) * | 1985-12-02 | 1987-06-15 | ||
| JP2004301215A (en) * | 2003-03-31 | 2004-10-28 | Hitachi Constr Mach Co Ltd | Hydraulic driving device for work vehicle |
-
1987
- 1987-07-28 JP JP11550287U patent/JPS6420504U/ja active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6293521U (en) * | 1985-12-02 | 1987-06-15 | ||
| JPH0539289Y2 (en) * | 1985-12-02 | 1993-10-05 | ||
| JP2004301215A (en) * | 2003-03-31 | 2004-10-28 | Hitachi Constr Mach Co Ltd | Hydraulic driving device for work vehicle |