JPH01141856U

JPH01141856U -

Info

Publication number: JPH01141856U
Application number: JP3927488U
Authority: JP
Priority date: 1988-03-24
Filing date: 1988-03-24
Publication date: 1989-09-28
Anticipated expiration: 2003-03-24
Also published as: JP2504571Y2

Description

[Brief explanation of the drawing]

第１図はこの考案にかかる油圧回路をそなえた
ホイール式シヨベルの側面図、第２図および第３
図はこの考案にかかる油圧回路図、第４図は従来
技術ホイール式シヨベルの側面図、第５図は従来
技術上部旋回体に配置されている機器などを示す
平面図である。２，１８……下部走行体、３，１９……上部旋
回体、５，２０……エンジン、７……作業機、１
２，１２′……第１ポンプ、１３，１３′……第
２ポンプ、１４，１４′……パイロツトポンプ、
２４，２５，２６，２７……アクチユエータ用切
換弁、２８，２９，３０，３１，３４……サブバ
ルブ、３２……パイロツト弁、３３……パイロツ
ト走行弁、３５……パイロツチ切換弁、３６……
ドーザ弁、３７……走行モータ。 Figure 1 is a side view of a wheeled excavator equipped with a hydraulic circuit according to this invention, Figures 2 and 3 are
FIG. 4 is a side view of a conventional wheel type shovel, and FIG. 5 is a plan view showing equipment arranged in a conventional upper revolving body. 2, 18... Lower traveling body, 3, 19... Upper revolving body, 5, 20... Engine, 7... Working machine, 1
2, 12'...first pump, 13,13'...second pump, 14,14'...pilot pump,
24, 25, 26, 27... actuator switching valve, 28, 29, 30, 31, 34... sub valve, 32... pilot valve, 33... pilot traveling valve, 35... pilot switching valve, 36...
Dozer valve, 37...travel motor.

Claims

[Scope of utility model registration request]

In a hydraulic excavator, the upper rotating body is equipped with a hydraulic actuator for work equipment, and the lower traveling body is equipped with an engine and its necessary equipment, a traveling motor for driving the traveling gear, and a switching valve for other actuators. Hydraulic actuators for working machines are divided into two groups A and B, and the switching valves for the actuators of groups A and B are all connected in parallel, and the switching valves for each actuator are connected so that they can be linked to the switching valves for pilot pressure oil. A sub-valve is provided, and when the actuator switching valve is in the neutral position, the sub-valve is set to the oil passage opening position, and when the actuator switching valve is in a position other than neutral, the sub-valve is set to the oil passage blocking position, and on the upstream side of groups A and B. A pilot valve is provided so that the oil passage for pump discharge pressure oil can be switched, and on the other hand, the first and second pumps, a pilot pump, a pilot travel valve, and a travel motor are arranged on the lower traveling body so that they can be linked to the pilot travel valve. A sub-valve for pilot pressure oil is provided, and when the pilot travel valve is in the neutral position, the sub-valve is set to the oil passage blocking position, and when the pilot travel valve is in a position other than neutral, it is set to the oil passage open position, and when the pilot travel valve is in the neutral position, it is set to the oil passage opening position. When the first pump is in the position, the pressure oil discharged from the first pump is supplied to the group A via another actuator switching valve and the pilot switching valve, and the pressure oil discharged from the second pump is supplied to the group B via the pilot travel valve.
When the pilot travel valve is in a position other than neutral, the pressure oil discharged from the first and second pumps can be combined and supplied to the travel motor, and when the travel motor and the hydraulic actuator for the work equipment are operated simultaneously. A hydraulic circuit for a hydraulic excavator, characterized in that the pressure oil discharged from the first pump can be supplied to a hydraulic actuator for a working machine, and the pressure oil discharged from the second pump can be supplied to a travel motor.