摘要:
To provide a hydraulic drive system for a work machine capable of securing a favorable operability in the case where hydraulic fluid discharged from a hydraulic actuator is regenerated for driving other hydraulic actuator. The hydraulic drive system for a work machine includes: a regeneration line that connects a bottom-side hydraulic chamber of a hydraulic cylinder to a portion between a hydraulic pump and a second hydraulic actuator; a regeneration flow rate adjustment device that supplies at least part of the hydraulic fluid discharged from the bottom-side hydraulic chamber to a portion between the hydraulic pump and the second hydraulic actuator through the regeneration line; a differential pressure calculating section that reads a pressure in the bottom-side hydraulic chamber of the hydraulic cylinder detected by a first pressure sensor and a pressure between the hydraulic pump and the second hydraulic actuator detected by a second pressure sensor, and calculates a differential pressure, or a differential pressure sensor; and a control unit that controls the regeneration flow rate adjustment device such as to gradually increase the flow rate of the hydraulic fluid flowing through the regeneration line according to an increase in the differential pressure calculated by the differential pressure calculation section or in the differential pressure detected by the differential pressure sensor.
摘要:
A hydraulic axle includes a reversible hydraulic pump. The hydraulic axle has a multi-surface cylinder with two retraction surfaces and two deployment surfaces. A first deployment surface and a first retraction surface are configured to interconnect with each other and separate from other surface during a rapid-traverse stroke. A pressure medium is configured to act on the second deployment surface to enable deployment.
摘要:
It is configured to have a first hydraulic pump connected to a drive source, a second hydraulic pump connected to a rotor of the first hydraulic pump, a first regulator valve that regulates pressure of the hydraulic oil discharged from the first hydraulic pump to a third oil passage that connects a discharge port of the first hydraulic pump and a hydraulic actuator, a fourth oil passage that connects the second hydraulic pump and a lubrication system of the hydraulic actuator, a second regulator valve that regulates pressure of the hydraulic oil discharged from the first regulator valve to a pressure lower than a line pressure, and an one-way valve that is installed in a second oil passage connecting the second hydraulic pump and a reservoir and permits supply of hydraulic oil from the reservoir only to the second hydraulic pump.
摘要:
Provided is construction machinery that is capable of greatly reducing the amount of fuel consumption by making effective use of recovered energy. The construction machinery has a first hydraulic pump 3 for discharging hydraulic oil for driving an actuator 6, a second hydraulic pump 9, a second prime mover 7 for driving the second hydraulic pump 9, energy storage device 8 for storing energy for driving the second prime mover 7, and a hydraulic oil supply circuit 10 including a hydraulic oil switching section 11c that accepts the hydraulic oil discharged from the first hydraulic pump and the hydraulic oil discharged from the second hydraulic pump and supplies either the mixture of the accepted hydraulic oils or a selected one of the accepted hydraulic oils to the actuator 6. The construction machinery includes a control device 20 that, when the drive efficiency of the second hydraulic pump 9 and/or the amount of energy stored in the energy storage device 8 is higher than a preselected setting value, outputs a switch command to the hydraulic oil switching section 11c and outputs a drive command to the second prime mover 7.
摘要:
Disclosed are a device for controlling a regenerated flow rate for a construction machine and a method for controlling the same, the device being able to supply a large chamber of an arm cylinder with a part of operating oil, which is discharged from the arm cylinder to an operating oil tank during arm-in driving, and regenerating the same. The present invention provides a device for controlling a regenerated flow rate for a construction machine, the device being characterized by comprising: a variable capacity-type hydraulic pump and a pilot pump; an arm cylinder driven by operating oil supplied from the hydraulic pump; a variable arm regeneration valve installed in a passage between the arm cylinder and the operating oil tank; and an electronic proportional valve installed in a passage between the pilot pump and the arm regeneration valve.
摘要:
Provided is a slewing-type working machine capable of reducing back pressure generated during slewing. The slewing-type working machine includes: a base carrier; an upper slewing body; a hydraulic motor 11 including first and second ports 11a and 11b and slewing the upper slewing body; a hydraulic pump 10, a slewing operation device 12 including an operating member 12a; a control valve 13 controlling the hydraulic motor 11 based on the operation signal of the slewing operation device 12; first and second pipe-lines 14, 15 connecting the first and second ports 11a and 11b of the hydraulic motor 11 to the control valve; a communication switching device 25 and 26 capable of switching communication and cutting of between both pipe-lines 14, 15 and the tank T; and a switching command section 27 operating the communication switching devices 25 and 26, when the upper slewing body is slewed, to bring only a pipe-line, which corresponds to a discharge-side pipe-line of the hydraulic motor 11, of the pipe-lines 14 and 15 into communication with the tank T, while bypassing the control valve 13.
摘要:
A hydraulic system and method for using the same are provided. The hydraulic system includes a pump, a first actuator having a first head chamber and a first rod chamber, and a second actuator having a second head chamber and a second rod chamber. The hydraulic system further includes a first control valve and a second control valve. The second control valve to selectively provide regeneration fluid flow from the first rod chamber to the first head chamber in response to a first function command is less than a first function command limit, a second function command is greater than a second function command limit, and a second function load is greater than a second function load limit.
摘要:
A hydraulic valve arrangement (1) is provided comprising comprising a supply port arrangement having a high pressure port (2) and a low pressure port (4), a working port arrangement having two working ports (6, 7), a first valve (13) arranged between said high pressure port (2) and said working port arrangement (6, 7), a second valve (14) arranged between said low pressure port (4) and said working port arrangement (6, 7), a controller (19) for controlling said first valve (13) and said second valve (14), said controller (19) having an input connection (20) for receiving a signal of an operator input device, and a regenerative flow path which can be established by means of at least one of said first valve (13) and said second valve (14). The function of such a hydraulic valve arrangement should be enhanced. To this end said controller (19) said controller interrupts said regenerative flow path when a feed pressure at said working port arrangement (6, 7) exceeds a predetermined pressure level.
摘要:
The present disclosure provides a hydraulic system for controlling a load. The system includes a housing defining an inlet, a first port, and a second port. The system further includes a spool valve and a proportional control element. The spool valve is in fluid communication with the inlet and the second port and the proportional control element is in fluid communication with the first port. The proportional control element can be controllable to exhaust fluid from the first port to a reservoir. In this arrangement, the proportional control element and the spool valve are controlled independently of one another.
摘要:
A circuit for driving a hydraulic cylinder of a construction machine includes: a hydraulic pump; a tank; a control valve; a bottom side line; a rod side line; a quick return circuit having a branch line branched off from the bottom side line and led to the tank and a quick return valve which allows hydraulic fluid to be flowed through the branch line only when the control valve is switched to a contraction driving position; and a recycling circuit which supplies a part of return fluid discharged from a bottom side fluid chamber to a rod side fluid chamber of the hydraulic cylinder. The recycling circuit allows the hydraulic fluid to be flowed only from the bottom side fluid chamber into the rod side fluid chamber of the hydraulic cylinder only when the hydraulic cylinder is switched to the contraction driving position.