JPH0177103U

JPH0177103U -

Info

Publication number: JPH0177103U
Application number: JP1987172195U
Authority: JP
Priority date: 1987-11-11
Filing date: 1987-11-11
Publication date: 1989-05-24

Description

[Brief explanation of the drawing]

第１図は本考案の１実施例を示す図、第２図は
他の実施例を示し第１図と異なる部分のみを示し
た図、第３図は従来技術による回路を示す図であ
る。１……ポンプ、２……ポンプ駆動回路、３……
アキユムレータ回路、４……分流弁、５……スプ
ール、６……ばね、７……パイロツトリリーフ弁
、８……チエツク弁、９……アキユムレータ、１
０……可変絞り、２１〜２４……切換弁、３１〜
３４……アクチユエータ。 FIG. 1 is a diagram showing one embodiment of the present invention, FIG. 2 is a diagram showing another embodiment, showing only the parts different from FIG. 1, and FIG. 3 is a diagram showing a circuit according to the prior art. 1...Pump, 2...Pump drive circuit, 3...
Accumulator circuit, 4... Diversion valve, 5... Spool, 6... Spring, 7... Pilot relief valve, 8... Check valve, 9... Accumulator, 1
0...Variable throttle, 21~24...Switching valve, 31~
34...actuator.

Claims

[Claims for Utility Model Registration] (1) A pump drive circuit consisting of a pump, a variable throttle, and a plurality of actuators that are driven by oil discharged from the pump via the variable throttle and whose driving directions are controlled by respective switching valves. and an accumulator circuit driven by pump discharge oil filled into the accumulator via the check valve, and a pressure upstream of the variable throttle at one end and fixed at the other end. The pressure downstream of the variable throttle and the elastic force of the spring are applied through the throttle, and in normal conditions, the pump communicates only with the variable throttle and responds to the pressure difference before and after the variable throttle, which acts in opposition to the elastic force of the spring. Hydraulic control consists of a built-in spool that changes pressure and communicates with the accumulator circuit, and a diversion valve that has a built-in pilot relief valve that relieves the pressure oil at the other end of the spool to the tank when the pressure exceeds a certain value. Device. (2) The hydraulic control circuit according to claim 1, wherein the pump is a variable pump with pressure compensation. (3) The hydraulic control device according to claim 1 or 2, wherein the variable throttle is a variable throttle whose opening degree is electromagnetically controlled.