Disclosed are a damping system for a movable arm of a loading machine and an operation machinery, which comprise a multi-way valve, a movable arm oil cylinder, a movable arm damping valve, and a damping lock. The multi-way valve comprises a movable arm valve core and a bucket valve core, a first movable arm oil port of the movable arm valve core communicates with a rod cavity of the movable arm oil cylinder, a second movable arm oil port of the movable arm valve core communicates with a rodless cavity of the movable arm oil cylinder, the rod cavity of the movable arm oil cylinder communicates with the movable arm damping valve, the rodless cavity of the movable arm oil cylinder communicates, via the damping lock, with the movable arm damping valve; a switching oil port of the damping lock communicates with an unloading position of the bucket valve core.

A hydraulic system (600) and method for reducing boom dynamics of a boom (30), while providing counter-balance valve protection, includes a hydraulic actuator (110), first and second counter-balance valves (300, 400), first and second control valves (700, 800), and first and second blocking valves (350, 450). A net load (90) is supported by a first chamber (116, 118) of the hydraulic actuator, and a second chamber (118, 116) of the hydraulic actuator may receive fluctuating hydraulic fluid flow from the second control valve to produce a vibratory response (950) that counters environmental vibrations (960) on the boom. The first blocking valve prevents the fluctuating hydraulic fluid flow from opening the first counter-balance valve. The first blocking valve may drain leakage from the first counter-balance valve.

A hydraulic apparatus comprises first and second manifolds each of which is connected to a plurality of actuators via corresponding actuator valves connected in parallel and operated responsive to inputs to regulate the flow of fluid to the actuators. A plurality of working chambers are connectable to either the first or second manifold and have a net flow which is controlled responsive to a negative feedback signal. The negative feedback signal is determined in response to a calculated pressure or flow rate in virtual fluid flow paths extending from the first and second manifolds.

Systems to control movement of a motor grader include a sensor for providing a bounce signal indicative of a bouncing movement of the motor grader, and a controller programmed with instructions that, when executed: receive the bounce signal from the sensor; analyze the bounce signal from the sensor; determine whether the maximum amplitude of the bouncing movement exceeds a threshold; in response to determining whether the maximum amplitude exceeds the threshold, generate an articulation angle command signal to change an articulation angle of the motor grader; and transmit the articulation angle command signal to change the articulation angle.

An excavator includes a traveling body, an upper turning body rotatably provided on the traveling body, an attachment which has a boom, an arm, and a bucket and is attached to the upper turning body, and a controller configured to perform a control of a cylinder of at least one shaft of the attachment so as to suppress a vibration of the traveling body or the upper turning body, which is caused by an aerial operation of the attachment.

A control system for controlling movement of a work element of a power machine can include a control device, and an operator input device in communication with the control device. The control device can be configured to receive, from the operator input device, a signal for controlling an actuator of the work element. The signal can be filtered, using a digital notch filter, to generate a filtered signal, and an actuator of the work element can be controlled based on the filtered signal.

A hydraulic machine. A boom actuator includes a large chamber and a small chamber. A recovery unit receives fluid discharged from the large chamber and then recovers energy. A recovery line connects the large chamber and the recovery unit. An accumulator is connected to a first point on the recovery line. A discharge valve is disposed on the recovery line between the first point and the recovery unit. A first sensor measures a pressure in the accumulator. A controller controls opening and closing of the discharge valve. The controller performs anti-bouncing control of: determining a target pressure in the accumulator corresponding to a load pressure applied to fluid in the large chamber by a load according to a predetermined correspondence; and controlling the opening and closing of the discharge valve such that the pressure in the accumulator measured by the first sensor reaches the target pressure.

A hydraulic system includes a first supply line connecting a boom control valve and a bottom side of a boom cylinder, a second supply line connecting the boom control valve and a rod side of the boom cylinder, a leveling switch valve having: a first operating position allowing a leveling operation of a working tool; and a first stopping position allowing the leveling operation to stop, a ride controller including: a ride-control switch valve connected to a branched fluid line branched from the first supply line; and an accumulator configured to perform an anti-vibrating operation for suppressing a pressure fluctuation of the boom cylinder, and a drain fluid line to discharge operation fluid in a downstream section extending from the leveling switch valve to the rod side of the boom cylinder in the second supply line when the leveling switch valve is switched to the first stopping position.

The invention relates to a method of controlling a working machine. The working machine comprises a first power source arranged to drive a mechanical driveline, a hydraulic system comprising a hydraulic pump and an actuator arranged to be driven to move by the hydraulic pump, where the hydraulic pump is separated from, or disconnectable from, the first power source. The method comprises determining whether the working machine is in an increased response mode. The method further comprises increasing a response of the hydraulic system upon determining that the working machine is in the increased response mode.

A working machine comprises an operation member for operating a hydraulic device via a control valve. An oscillation calculator acquires a specific value corresponding to a feature representing oscillation of the operation member when the feature appears in variation of an control signal output according to an operation amount of the operation member within one of a sequence of predetermined periods, and calculates an evaluation value representing a degree of oscillation of the operation member by adding up the specific value or values obtained within one or more of the predetermined periods. A control signal generator generates a control signal for controlling the control valve based on the operation signal. The control signal generator decreases a value of the control signal per a unit value of the operation signal as the evaluation value gradually increases with the elapse of one or more of the sequence of the predetermined periods.