JPS6168160U

JPS6168160U -

Info

Publication number: JPS6168160U
Application number: JP15403384U
Authority: JP
Priority date: 1984-10-11
Filing date: 1984-10-11
Publication date: 1986-05-10

Description

[Brief explanation of drawings]

第１図は本考案の実施例を示す油圧回路図、第
２図は絞り選択弁の一例を示す断面図、第３図は
絞り選択弁の別の実施例を示す油圧回路図、第４
図は油圧シヨベルの一例を示す側面図である。５…アームシリンダ、５ａ…ヘツド側油室、５
ｂ…ロツド側油室、６…アーム、９…油圧ポンプ
、１０…アーム用方向制御弁、１１，１２…流路
、１３…逆止弁、１４…絞り選択弁、１５ａ…絞
り（開口面積小）、１５ｂ…絞り（開口面積大）
、１７…パイロツト流路、１８…遠隔操作弁、１
９…パイロツトポンプ、２０…タンク。 Fig. 1 is a hydraulic circuit diagram showing an embodiment of the present invention, Fig. 2 is a sectional view showing an example of the throttle selection valve, Fig. 3 is a hydraulic circuit diagram showing another embodiment of the throttle selection valve, and Fig. 4 is a hydraulic circuit diagram showing an example of the throttle selection valve.
The figure is a side view showing an example of a hydraulic excavator. 5...Arm cylinder, 5a...Head side oil chamber, 5
b... Rod side oil chamber, 6... Arm, 9... Hydraulic pump, 10... Directional control valve for arm, 11, 12... Channel, 13... Check valve, 14... Throttle selection valve, 15a... Throttle (small opening area) ), 15b...Aperture (large aperture area)
, 17...Pilot channel, 18...Remote control valve, 1
9... Pilot pump, 20... Tank.

Claims

[Scope of utility model registration request]

Among the flow paths connected to the oil chambers on the rod side and head side of the arm cylinder that rotates the arm of the hydraulic excavator, oil is only supplied to the cylinder side through the flow path that becomes the return side when the arm is pulled. A check valve that allows the above-mentioned flow path, and a throttle selection valve that has a plurality of throttle sections with different opening areas and whose throttle section communicating with the flow path is selected by a remote control means are provided in parallel. Hydraulic excavator hydraulic circuit features.