JPS579302A - Unload valve - Google Patents
Unload valveInfo
- Publication number
- JPS579302A JPS579302A JP8139480A JP8139480A JPS579302A JP S579302 A JPS579302 A JP S579302A JP 8139480 A JP8139480 A JP 8139480A JP 8139480 A JP8139480 A JP 8139480A JP S579302 A JPS579302 A JP S579302A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- main
- oil
- discharge
- pump
- 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
Landscapes
- Operation Control Of Excavators (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
PURPOSE: To effectively utilize the output of a prime mover by controlling the pressure-receiving area of two pilot pressure receiving members to make it a value proportional to the total discharge amount of the main pumps in the unload valve of an oil-pressure circuit with plural pumps.
CONSTITUTION: In an oil-presssure circuit having the main pumps 2 and 3 and an accelerating pump 4 whose oil pressure is jointed with the oil pressure of the main pump 3, the discharge pressures of the main pumps 2 and 3 as pilot pressures are acted on an unload valve 6, and the accelerating pump 4 is unloaded in the position II. Then, in the unload valve 6, the values of the pressure-receiving areas A and B of the pilot pressure-receiving members 15 and 16 are controlled so as to proportionate to the total discharge amounts D1 and D1+D2 (where D1 is the discharge amounts of the main pumps 2 and 3 and D2 is the discharge amount of the accelerating pump 4. And, when the formula D1Sp1+(D1+D2)Sp1≥F where S is a constant, p1 is the discharge pressure of the main pump 2, and F is the pushing force of a spring 14, is met, the valve 6 is switched to the position II.
COPYRIGHT: (C)1982,JPO&Japio
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8139480A JPS579302A (en) | 1980-06-18 | 1980-06-18 | Unload valve |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8139480A JPS579302A (en) | 1980-06-18 | 1980-06-18 | Unload valve |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS579302A true JPS579302A (en) | 1982-01-18 |
Family
ID=13745080
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP8139480A Pending JPS579302A (en) | 1980-06-18 | 1980-06-18 | Unload valve |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS579302A (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58224561A (en) * | 1982-06-21 | 1983-12-26 | Sharp Corp | Switching type constant-voltage circuit |
JPS61131139U (en) * | 1985-02-05 | 1986-08-16 | ||
EP3943756A4 (en) * | 2019-03-19 | 2022-11-30 | Yanmar Power Technology Co., Ltd. | Hydraulic circuit for construction machine, and hydraulic circuit |
-
1980
- 1980-06-18 JP JP8139480A patent/JPS579302A/en active Pending
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS58224561A (en) * | 1982-06-21 | 1983-12-26 | Sharp Corp | Switching type constant-voltage circuit |
JPS61131139U (en) * | 1985-02-05 | 1986-08-16 | ||
EP3943756A4 (en) * | 2019-03-19 | 2022-11-30 | Yanmar Power Technology Co., Ltd. | Hydraulic circuit for construction machine, and hydraulic circuit |
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