Hydraulic system for work machine

    公开(公告)号:US10253479B2

    公开(公告)日:2019-04-09

    申请号:US14915311

    申请日:2015-01-09

    摘要: When option attachment has not been attached, a reserve flow/direction control valve 8 is made to operate as a center bypass cut valve. When an option attachment has been attached, switching control is performed. In the switching control, when the option attachment is not used, the reserve flow/direction control valve 8 is made to operate as a center bypass cut valve for adjusting composite opening area of a center bypass and thereby controlling the flow rate of hydraulic fluid flowing into an actuator. When the option attachment is used, the reserve flow/direction control valve 8 is made to operate so as to supply the hydraulic fluid to an option hydraulic actuator 14.

    Work Machine
    3.
    发明申请
    Work Machine 有权
    工作机器

    公开(公告)号:US20150252819A1

    公开(公告)日:2015-09-10

    申请号:US14436395

    申请日:2013-10-17

    摘要: Provided is a work machine including: a variable-displacement pump 2; an actuator 5 driven by a hydraulic fluid delivered from the pump 2; a flow control valve 4 of an open-center type that controls a flow rate of the hydraulic fluid supplied to the actuator 5; a bleed-off line 8a connecting the actuator flow control valve 4 to a tank 6; a bleed-off flow control valve 8 disposed in the bleed-off line 8a; an operating device 3 that specifies operation of the actuator 5; a bleed-off control device 14 that controls a degree of opening of the bleed-off flow control valve 8 in accordance with an amount of manipulation of the operating device 3; and a pump control device 15 that controls, in accordance with the degree of opening of the bleed-off flow control valve 8, a pump flow rate by correcting a reference pump flow rate that is based on the amount of manipulation of the operating device 3. The work machine with this configuration can save energy while at the same time inhibiting an occurrence of a sense of strangeness or discomfort in particular operation.

    摘要翻译: 提供了一种作业机械,包括:可变排量泵2; 由从泵2输送的液压流体驱动的致动器5; 开放式流量控制阀4,其控制供应到致动器5的液压流体的流量; 将致动器流量控制阀4连接到罐6的排出管线8a; 设置在排出管线8a中的排出流量控制阀8; 指定致动器5的操作的操作装置3; 泄放控制装置14,其根据操作装置3的操纵量来控制排出流量控制阀8的打开程度; 以及泵控制装置15,其根据排出流量控制阀8的打开程度,通过基于操作装置3的操作量校正基准泵流量来控制泵流量 具有这种结构的工作机器可以节省能量,同时抑制特殊操作中的异常感或不适感。

    Hybrid-type construction machine
    6.
    发明授权

    公开(公告)号:US09725878B2

    公开(公告)日:2017-08-08

    申请号:US14915304

    申请日:2014-09-18

    摘要: Provided is a hybrid-type construction machine including a swing device of the hydraulic-electric combined swing type and by which, in a work for which accurate swing operability is demanded like, for example, a crane work, a swing body is driven alone by the electric motor.The hybrid-type construction machine includes an engine, a hydraulic pump driven by the engine, a swing body, an electric motor for driving the swing body, and a hydraulic motor driven by the hydraulic pump for driving the swing body. The swing body is swung by simultaneous drive by the electric motor and the hydraulic motor. The hybrid-type construction machine includes a control apparatus having a work mode changeover unit by which an operator changes over a mode in response to an aspect of a work and an electric alone swing controlling unit configured to control the swing body to be swung by the electric motor alone. When a work in which position accuracy is demanded is selected by the work mode changeover unit, the swing body is swung by the electric alone swing controlling unit.

    Hydraulic Control Device for Work Machine
    7.
    发明申请
    Hydraulic Control Device for Work Machine 审中-公开
    工作机液压控制装置

    公开(公告)号:US20150300378A1

    公开(公告)日:2015-10-22

    申请号:US14441048

    申请日:2013-11-05

    IPC分类号: F15B11/028 E02F9/22

    摘要: The energy efficiency is increased by reducing the throttle/relief loss in the delivery flow of the hydraulic pump caused by the bleed-off control, while also making it possible to control the delivery pressure of the hydraulic pump according to the operation amount of the control lever unit and improving the operational performance. A controller 6 includes a target pump pressure setting unit 32 which calculates a target pump delivery pressure which increases with the increase in an operation amount signal from an operation amount detector 20A/20B based on the operation amount signal and a pump flow rate upper limit setting unit 33 which calculates a pump flow rate upper limit which increases with the increase in the operation amount signal based on the operation amount signal. The tilt amount of the hydraulic pump 2 is controlled based on the target pump delivery pressure calculated by the target pump pressure setting unit 32, the pump flow rate upper limit calculated by the pump flow rate upper limit setting unit 33, and the delivery pressure of the hydraulic pump 2 detected by a pressure detector 21.

    摘要翻译: 通过减少由排出控制引起的液压泵的输送流量中的节流/减压损失,能够提高能量效率,同时还可以根据控制的操作量来控制液压泵的输送压力 杠杆单元,提高操作性能。 控制器6包括目标泵压力设定单元32,该目标泵压力设定单元32基于操作量信号和泵流量上限设定来计算随着来自操作量检测器20A / 20B的操作量信号的增加而增加的目标泵输送压力 单元33,其基于操作量信号计算随着操作量信号的增加而增加的泵流量上限。 基于由目标泵压力设定单元32计算出的目标泵输送压力,由泵流量上限设定单元33计算的泵流量上限,以及泵流量上限设定单元33的输出压力来控制液压泵2的倾斜量 液压泵2由压力检测器21检测。

    Construction machinery
    9.
    发明授权

    公开(公告)号:US10221871B2

    公开(公告)日:2019-03-05

    申请号:US15422152

    申请日:2017-02-01

    摘要: The Construction machinery includes at least two actuators, a main pump that generates hydraulic energy for driving the actuators, control valves disposed between the main pump and the actuators, a hydraulic pump motor driven by the generator motor that generates energy to be added to the hydraulic energy, and a controller that reduces hydraulic energy generated by the main pump when the hydraulic pump motor driven by the generator-motor generates energy. The construction machinery further comprises changeover valves that selectively change a location at which the energy from the hydraulic pump motor driven by the generator-motor is to be added according to the actuators. The controller changes a reduction rate of the hydraulic energy generated by the main pump depending on a specific actuator to which the energy is to be added.