A method for controlling a work vehicle includes driving a first hydraulic pump and a second hydraulic pump by an engine to supply hydraulic fluid to a first hydraulic motor and a second hydraulic motor, respectively, to drive a first traveling device and a second traveling device, respectively. An operation state of a direction input device to operate a traveling direction of the work vehicle is detected. Based on the operation state detected, whether or not a traveling state of the work vehicle is a turning state. When it is determined that the traveling state is the turning state, a rotation command to decrease a target rotational speed of the engine from a first rotational speed to a second rotational speed is output.

The skid steer manure spreader attachment includes a main bucket compartment, a cover, and a beater shaft. The bucket, cover, and beater shaft are preferably formed of welded steel. The bucket has an industry standard quick attach plate on the back so it can be quickly attached to any standard skid steer, and is a standard width. A hydraulic motor operates the beater shaft and the cover. The beater shaft has blades angled in two directions. The beater shaft spins forward so the beater blades through manure out of the top of the bucket, above the shaft. The hydraulic motor drives the top sprocket, and a chain drives the bottom sprocket. A tensioner pivots on one screw to allow the user to tension the chain as needed.

A hybrid power unit of a work machine includes an engine and an energy storage device. The engine includes a crankshaft for driving a load and the crankshaft is attached to an energy storage device via a clutch. The energy storage device can be charged by the engine to store energy, that may be used to provide, when required, a boost to engine performance. The clutch may engage/disengage the energy storage device from the engine and/or control a clutch pressure. The clutch protects the crankshaft from shock loading and can slip to prevent over-torqueing of the crankshaft.

A hydraulic system for a working machine, the system comprising: an electric machine connected to a first hydraulic machine and to a second hydraulic machine via a common axle, an output side of the second hydraulic machine being connected to an input side of the first hydraulic machine, wherein the first hydraulic machine is a variable displacement hydraulic machine with unidirectional flow; at least one hydraulic consumer hydraulically coupled to an output side of the first hydraulic machine via a supply line and configured to be powered by the first hydraulic machine; a first return line hydraulically coupling the hydraulic consumer to the input side of the first hydraulic machine.

A system and method for excavating an aggregate from below or beside a foundation through an access hole is provided. The system includes an air compressor and an air line fluidly coupled to the air compressor. The system further includes a valve disposed in fluid communication on the air line, and an end effector in fluid communication with the air compressor. The end effector extends between a first end coupled to one of the air line or the valve and a second end. The end effector is sized to fit through the access hole. The system further includes a nozzle coupled to the second end of the end effector.

A controller mounted in a work machine limits a velocity at which a work device approaches a design surface to be equal to or lower than a predetermined limiting velocity in such a manner that the work machine is located above the design surface when an operation device is operated. The controller determines whether a work phase of the work device is compaction work on the basis of a posture of a bucket with respect to the design surface in a case in which the operation device instructs the work device to approach the design surface, and sets the limiting velocity when determining that the work phase of the work device is the compaction work to be higher than the limiting velocity when determining that the work phase of the work device is other than the compaction work.

A system and method for compensating reduced track speed because of engine droop for a work machine is disclosed. The system may comprise a frame, an attachment coupled to the frame, a ground-engaging mechanism adapted to support the frame, an engine, a motor, a track speed sensor, an engine speed sensor, and a controller. The engine may drive the ground-engaging mechanism and attachment. The engine may be coupled through a variable speed transmission to the ground-engaging mechanism and the attachment. They variable speed transmission may include a hydrostatic circuit. The controller may be adapted to send an increased transmission command signal based on a drop in the engine speed signal when the work machine engages an increased load. The increased transmission command signal may increase a motor speed to cause an increase in track speed to compensate at least a portion of the reduced track speed from the engine speed droop.

Provided is a hydraulic circuit, for a construction machine, which drives an actuator by merging pressure oil from a fixed-volume pump into a center bypass oil path from a variable-volume pump to an oil tank, wherein the flow rate of flow from the fixed-volume pump to the center bypass oil path can be controlled in accordance with a requested flow rate of the actuator. A distribution direction-switching valve, which has a first oil path from a fixed-volume pump to an oil tank and a second oil path from the fixed-volume pump to a first center bypass oil path, has a first signal reception unit which causes a spool to slide in a direction in which the first oil path is formed, and a second signal reception unit which causes a spool to slide in a direction in which the second oil path is formed, and determines a distribution ratio of pressure oil flowing to the first oil path and the second oil path in accordance with the difference in size of the signals received by the first signal reception unit and the second signal reception unit, the first signal reception unit receiving a signal based on a negative control signal.

A direction control valve group for a construction machine that controls an amount of pressure oil supplied to a hydraulic actuator from a hydraulic pump that discharges the pressure oil is provided. The direction control valve includes a cylinder port that supplies the pressure oil to the hydraulic actuator, a bridge passage that is switchably connected and disconnected to the cylinder port according to a change in position of a first spool, and an internal passage that supplies the pressure oil discharged from the hydraulic pump to the bridge passage. The first spool is provided in the internal passage.

A drive control method of a hydraulic actuator of a construction machine includes: determining whether a rotation operation lever and a working device operation lever are operated; calculating the required pressure of a hydraulic cylinder fix a working device according to the operation amount of the rotation operation lever; calculating the required flow rates of a swing motor and the hydraulic cylinder for the working device, the required flow rates corresponding to the operation amounts of the working device operation lever and the rotation operation lever; calculating the opening areas of the first and second proportional solenoid valves of an inlet side and an outlet side by using the calculated required pressure and required flow rates of the hydraulic cylinder for the working device and the swing motor; and calculating current values to be inputted into the first and second proportional solenoid valves of the inlet side and the outlet side according to preset data values or a table in comparison with the calculated opening areas of the first and second proportional solenoid valves of the inlet side and the outlet side.