A slewing hydraulic work machine includes a slewing control device performing a slewing control in accordance with an applied slewing command operation, a boom control device performing a boom-raising control in accordance with an applied boom-raising command operation, a boom angle detector, and a capacity control section. The capacity control section calculates a command motor capacity based on a boom angle, generates a capacity command signal corresponding to the command motor capacity and inputs the signal to a slewing motor. During the performance of slewing and boom-raising operation, the capacity control section sets the command motor capacity to a value equal to or less than a base capacity when the boom angle is equal to or less than a slewing priority angle and sets the command motor capacity to a value greater than the base capacity when the boom angle is greater than the slewing priority angle.

A drive assembly for a work vehicle has a drive housing, including a first housing element forming a reaction member, a drive shaft, a planetary gear set coupled to the drive shaft and configured to selectively rotate an output element. The planetary gear set has an input component, an output component and a reaction component. One or more input clutch arrangements at an input side of the drive assembly are configured to selectively interface with the planetary gear set to effect a rotation speed of the output element. A control clutch arrangement interfaces with the reaction member and the reaction component. The control clutch arrangement is configured to selectively couple and decouple the reaction member from the reaction component to damp a torque increase transmitted to the output element.

A shovel includes a lower traveling body, an upper turning body turnably mounted on the lower traveling body, a cab mounted on the upper turning body, an attachment attached to the upper turning body, a hardware processor, and a display device. The hardware processor is configured to move the end attachment of the attachment relative to an intended work surface in response to a predetermined operation input related to the attachment. The display device is configured to display information on the hardness of the ground.

A shovel includes a lower traveling body, an upper turning body turnably mounted on the lower traveling body, a cab mounted on the upper turning body, an attachment attached to the upper turning body, a hardware processor, and a display device. The hardware processor is configured to move the end attachment of the attachment relative to an intended work surface with the ground being pressed with a predetermined force by the working part of the end attachment, in response to a predetermined operation input related to the attachment. The display device is configured to display information on an irregularity of the ground.

When the vehicle speed increases and reaches a predetermined switching threshold, the controller reduces the displacement of the first travel motor and controls the flow rate control device to offset a flow rate excess in the hydraulic circuit in accordance with the reduction in the displacement of the first travel motor. After the vehicle speed has reached the switching threshold, the controller executes switching control to switch the clutch from an engaged state to a disengaged state.

To install an energy storage device with sufficient capacity thereby to extend operating time of an electric work machine, even for a small electric work machine. A hydraulic excavator, as an electric work machine, includes an electric motor, an energy storage device that stores electric power for driving the electric motor, and a hydraulic pump driven by the electric motor. The electric motor and the hydraulic pump are vertically located alongside.

Provided are an energy regeneration device which can regenerate energy of a working fluid discharged from an actuator while controlling a flow rate of the working fluid, and a work machine including the foregoing device. The regeneration device (100) includes a boom cylinder (20), an inertial fluid container (102), an oil tank (110), an accumulator (105), a low-pressure-side opening/closing device (103), and a high-pressure-side opening/closing device (104). A calculation unit (151) calculates a duty ratio for opening/closing the low-pressure-side opening/closing device (103) and the high-pressure-side opening/closing device (104) in accordance with a desired flow rate of a working fluid discharged from the boom cylinder (20). A regeneration control unit (153) selects alternately the low-pressure-side opening/closing device (103) and the high-pressure-side opening/closing device (104) as a destination with which the inertial fluid container (102) communicates in accordance with the calculated duty ratio, and supplies a discharged working fluid to an accumulator (105).

Disclosed embodiments are directed to distributed hydraulic systems, and power machines such as excavators including distributed hydraulic systems. In the distributed hydraulic systems, electronically controlled distributor blocks are located throughout the machine, particularly along the lift arm, to locally distribute hydraulic power to actuators of the various machine and implement functions. Distributing control of hydraulics in multiple locations reduces the number of hoses that must be routed from a main control valve to the various actuators on the machine.

The present invention pertains to method for monitoring operation of a hydraulic system, in particular of a hydraulic system of a working machine, having at least one hydraulic actuator. The method comprises a step of determining a predefined operating condition of the hydraulic system; a step of determining an input power parameter being indicative of a power provided by an engine to the hydraulic system during the predetermined operating condition; a step of determining an output power parameter being indicative of a power provided by the hydraulic actuator during the predetermined operating condition; and a step of determining a fault condition of the hydraulic system based on the input power parameter and the output power parameter.

A housing of a multi-control valve includes an arm parallel passage, an arm crowding supply passage, an arm pushing supply passage, a boom parallel passage, a boom raising supply passage, and a boom lowering supply passage. The housing further includes: a slide hole; a head-side passage that is branched off from the boom raising supply passage and extends to the slide hole; a rod-side passage that is branched off from the boom lowering supply passage and extends to the slide hole; and a regeneration passage that extends from the slide hole to the arm parallel passage. The slide hole receives a boom sub spool therein. The boom sub spool is either a boom recycling spool or a boom regeneration spool.