The invention relates to a hydraulic system for a work machine. The system comprising: a main hydraulic machine connected to an output shaft of an engine of the work machine for providing power to working hydraulics of the work machine; a main pressure line connecting the main hydraulic machine to the working hydraulics; a support hydraulic machine connected to the output shaft; a hydraulic accumulator; a discharge valve connected between the accumulator and an input side of the support hydraulic machine; a charge valve connected between an output side of the support hydraulic machine and the hydraulic accumulator to selectively allow a flow from the support hydraulic machine to the hydraulic accumulator; a flow support valve connected between the output side of the support hydraulic machine and the main pressure line to selectively allow a flow from the support hydraulic machine to the main pressure line; and a hydraulic tank connected to the input side of the support hydraulic machine.

A hydraulic supply system provides hydraulic power to functional systems of a work vehicle and includes first and second hydraulic circuits. The first hydraulic circuit includes a first fluid pump operable to generate a first hydraulic fluid, a pressure storage reservoir coupled with the first fluid pump, and a first port coupled with the first fluid pump and with the pressure storage reservoir operable to store a reserve hydraulic fluid. The first port delivers a boost hydraulic fluid from the first circuit for use by the work vehicle to operate a first functional system of the work vehicle. The second hydraulic circuit includes a second fluid pump that generates a second hydraulic fluid, and a second port coupled with the second fluid pump delivers the second hydraulic fluid from the second hydraulic circuit for use by the work vehicle to operate a second functional system of the work vehicle.

A hydrostatic drive includes at least one hydrostatic pump configured to supply at least one hydrostatic consumer and an apparatus for an energy recovery procedure of at least a part of the energy that is output by the consumer. An electronic control unit or at least one software component is further included, with which the energy recovery procedure is controlled in a variable manner and depends upon detected influencing variables.

An excavator including a lower traveling body; an upper turning body turnably mounted to the lower traveling body; a work attachment attached to the upper turning body; an imaging device mounted to the upper turning body; a hydraulic actuator; a hydraulic pump configured to supply hydraulic oil to the hydraulic actuator; an electric motor configured to drive the hydraulic pump; an operation device of an electric type configured to operate the hydraulic actuator; and a control device configured to control the electric motor, wherein in response to determining that the operation device is not operated, the control device causes the hydraulic pump to automatically stop, and subsequently, in response to determining that an operation with respect to the operation device is started, the control device causes the hydraulic pump to be automatically activated.

A low idling controller (26A) switches an idling state flag from “clear” to “set” upon detecting a non-operation of an operating device (14). A rotational speed controller (26B) switches a rotational speed command from a set rotational speed by a rotational speed command device (27) to a low idling rotational speed based upon the idling state flag. At this time, an engine (8) drives in the low idling rotational speed lower than the set rotational speed. A gate controller (24) stops switching of an inverter (23) while the low idling controller (26A) is lowering a rotational speed of the engine (8).

A work machine includes a traveling body, a work attachment, and a processing circuitry configured to receive a reservation of an execution of a predetermined function in accordance with an input received by the work machine or in accordance with a signal received from an external apparatus and execute the predetermined function of the reservation, based on an execution condition designated by the reservation.

An example hydraulic system includes a hydraulic cylinder actuator comprising a cylinder and a piston, wherein the piston comprises a piston head and a rod extending from the piston head, wherein the piston head divides an internal space of the cylinder into a first chamber and a second chamber, and wherein the hydraulic cylinder actuator is unbalanced; a first pump driven by a first electric motor to provide fluid flow to the first chamber or the second chamber of the hydraulic cylinder actuator to drive the piston; a boost flow line; a hydraulic motor actuator; and a second pump driven by a second electric motor, wherein the second pump is fluidly coupled to the boost flow line to provide boost fluid flow to the hydraulic cylinder actuator.

The work vehicle 1 includes a main controller 100 that controls a travel driving force and a work driving force. The main controller 100 includes a travel remaining time calculating unit 111 that calculates a remaining time until a target rise/run distance is reached as a travel remaining time t.sub.C, a work remaining time calculating unit 112 that calculates a remaining time until a target arm angle is reached as a work remaining time t.sub.1, a rise/run determining unit 113 that determines whether rise/run is being performed or not, a correction rate setting unit 114 that sets a travel correction rate η.sub.C that adjusts a travel driving torque and a work correction rate η.sub.I that adjusts a work driving torque based on the travel remaining time t.sub.C, the work remaining time t.sub.1, and the rise/run determination flag, and an engine torque distribution calculating unit 115 that calculates a travel driving torque command and a work driving torque command based on the travel correction rate η.sub.C and the work correction rate η.sub.I.

A transmission assembly for a work vehicle having an engine includes a variator operably connected to the engine, a gear arrangement configured to provide a selective gear reduction for transmission of output power from the variator to an output shaft, and an electrical machine unit. The electrical machine unit further includes a main shaft operably connected to the variator, a first rotor configured to rotatably drive a first shaft, a second rotor configured to rotatably drive a second shaft, and a clutch configured to selectively couple the first shaft or the second shaft, or both the first shaft and the second shaft, to the main shaft. The clutch, the first rotor, and the second rotor are operable to control a speed and rotational direction of the main shaft in providing rotational power to the variator.

An example hydraulic system includes a hydraulic actuator; a pump driven by an electric motor and having an inlet port and an outlet port; a boost flow line configured to provide boost fluid flow or receive excess fluid flow; a reservoir fluid line fluidly coupled to a reservoir; and a valve assembly configured to operate in a plurality of states to allow the pump to operate in a closed-circuit configuration in which fluid discharged from the hydraulic actuator is provided to the inlet port of the pump or an open-circuit configuration in which fluid discharged from the hydraulic actuator is provided to the reservoir.