This disclosure relates to a hydraulic system for a hydro-mechanical machine comprising a rotary mechanism and a boom cylinder The hydraulic system includes a primary accumulator configured to receive and store high-pressure fluid in response to starting and stopping of the rotary mechanism. A control system configured to enable passage of the high-pressure fluid stored in the primary accumulator to a rotary control valve configured to control the rotary mechanism, and a boom control valve configured to control the boom cylinder through the hydraulic supply circuit, based on a predefined pressure threshold associated with the primary accumulator. A secondary accumulator coupled to the primary accumulator and the control system via the hydraulic supply circuit is configured to store surplus high-pressure fluid provided by the primary accumulator through the hydraulic supply circuit.

A work machine includes a mechanical arm. A work implement is coupled to the mechanical arm to receive a load. A hydraulic actuator moves the arm between a lower position and an upper position, wherein a distance between the lower position and the upper position is a travel distance of the mechanical arm. A sensor unit is configured to sense the load in the work implement. A valve is in fluid communication with the hydraulic actuator for supplying a fluid output to the hydraulic actuator. A controller is in communication with the valve and the sensor unit. The controller is configured to transmit a control signal to the valve to adjust the fluid output to the hydraulic actuator. The controller is also configured to adjust the upper position to reduce the travel distance in response to the load being at or above a threshold value.

In a control method for construction machinery, an operation performed by the construction machinery is divided into a plurality of subordinate works. A current subordinate work currently performed by the construction machinery is determined. A maximum absorbing torque of a hydraulic pump is adjusted according to the determined subordinate work. An engine speed change map is adjusted according to the determined subordinate work.

In a work machine, a load information output part outputs a load calculated by a load calculation part as load information before a piston member shifting toward a stroke end reaches a specific position, and a load storage part stores the load calculated by the load calculation part as a specific load when the piston member shifting toward the stroke end reaches the specific position. The load information output part further outputs the specific load as the load information after the piston member shifting toward the stroke end enters a specific region.

A hydraulic system of a working machine includes a hydraulic pump to output a hydraulic fluid, at least one proportional valve to deliver the hydraulic fluid to a supply target, a valve body including the proportional valve, a heat-up fluid passage in the valve body and into which the hydraulic fluid flows, a switching valve switchable between an open position in which the hydraulic fluid passing through the heat-up fluid passage is supplied to a hydraulic device and a closed position in which the hydraulic fluid is not supplied thereto and the hydraulic fluid from the hydraulic device is to be returned, a controller to operate the switching and proportional valves, and a return circuit through which the hydraulic fluid flowing into the heat-up fluid passage is returned as a result of at least one of the switching and proportional valves being operated by the controller.

A work machine control system includes: a pump; a cylinder operating a working equipment element in a movable range based on hydraulic oil supplied from the pump; a first path connected to the pump; a second path branching from the first path; a control valve adjusting the flow rate of the oil supplied to the cylinder via the first path; a bleed valve adjusting the flow rate of the oil discharged to a tank via the second path; a sensor detecting a posture of the element in the range; and a control device outputting a first command for adjusting the flow rate of the oil supplied to the cylinder and a second command for adjusting the flow rate of the oil discharged to the tank when element is determined to be present in an end section of the range based on detection data of the sensor.

One embodiment of a hydraulic system for a machine has a first hydraulic circuit including a first pump coupled to a first hydraulic actuator configured to move a first implement of the machine. A second hydraulic circuit includes a second pump coupled to a second hydraulic actuator configured to move a second implement. An electric motor mechanically couples to the first pump and to the second pump. An operator interface receives input from an operator requesting movement of the first and second implements. A controller communicatively coupled to the electric motor and to the operator interface determines, based on the requested movement of the first and second implements respectively, first and second flow allocations respectively for the first and second pumps and determines respective target displacements for the first and second pumps. The controller also determines first and second target electric motor speeds based on the target displacements for the first and second pumps, respectively, and controls the electric motor to operate at the larger of the first and second target electric motor speeds.

A work machine includes systems and methods for stability control based on operating values. The work machine includes a control system having a sensor system with a load sensor, an arm position sensor, and an articulation angle sensor. A controller is in communication with the sensor system. The controller is configured to receive a movement command and to receive a set of values from the sensor system. The controller is configured to determine an operational window for normal operation of the work vehicle based on the received set of values, determine a movement limit based on the received set of values, and limit movement of a component beyond the movement limit.

A working machine includes an undercarriage supported by first and second ground engaging units powered by first and second drive units, a main frame supported by the undercarriage, a first sensor configured to sense an orientation and relative angular motion of the main frame with respect to the undercarriage, a second sensor configured to sense an orientation and relative angular motion of the main frame in an external reference frame independent of the undercarriage, and a controller functionally linked to the first and second sensors. The controller is configured to receive commands corresponding to an intended movement of the first and second ground engaging units, and generate control signals to the first and second drive units to achieve or maintain the intended movement taking into account a detected orientation of the main frame relative to the undercarriage and a detected orientation of the main frame in the external reference frame.

A regeneration device includes: a regeneration valve that controls the flow rate of an operating fluid being drained from one port of a cylinder; a non-return valve that allows a regenerative flow of the operating fluid from the regeneration valve to the other port of the cylinder and blocks an opposite flow of the operating fluid; and an exhaust valve that controls the flow rate of the operating fluid output from the regeneration valve being drained to a tank. The regeneration valve controls the flow rate independently of the exhaust valve.