A hydraulic system for a working machine includes a traveling motor to output power to a traveling device in the working machine, a first detector to detect a physical quantity that changes in accordance with a traveling state of the working machine and that is detected at intervals of a predetermined period, and a controller to execute automatic shift-down to automatically reduce a rotational speed of the traveling motor to a first speed stage when the rotational speed of the traveling motor is in a second speed stage higher than the first speed stage. The controller is configured or programmed to determine a tendency or degree of change in the physical quantity, based on values of the physical quantity detected at intervals of the predetermined period by the first detector.

An automatic vehicle speed control system for use in a vehicle having an implement is disclosed. The automatic vehicle speed control system includes: a controller configured to: set a speed of the vehicle to a creep setting; monitor one or more operating conditions of the implement; and automatically adjust the speed of the vehicle based on the one or more operating conditions of the implement.

A control system of a power machine can be configured to allow certain power machine functionality based on a wireless connection with a mobile device. For example, a power machine can operate in a startup mode providing limited functionality to an operator (e.g., engine power, but no workgroup actuators). Access to additional power machine functionality (e.g., full functionality) can then be permitted based on establishing a wireless connection to a mobile device that corresponds to an operator profile for the power machine.

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.

A work vehicle includes a rotary member, a support member, a sealing ring, a pressure controller, and a vehicle speed determination component. The rotary member has a first hydraulic fluid supply channel to supply the hydraulic fluid to the steering clutch, and is rotated by power from the transmission when the steering clutch is engaged. The sealing ring is disposed between the rotary member and the support member and is mounted adjacent to the connected part between the first hydraulic fluid supply channel and the second hydraulic fluid supply channel. The pressure controller controls the engagement pressure to be a specific first pressure when the vehicle speed is determined not to be equal to or greater than a specific speed, and controls the engagement pressure to decrease from the first pressure when the vehicle speed is determined to be equal to or greater than a specific speed.

A process for execution by a processor of an electronic control unit (ECU), comprising: (a) detecting an operator command to align an upper structure of a tracked vehicle relative to a lower structure of the tracked vehicle; (b) in response to detection of the operator command, applying controlled rotation of the upper structure relative to the lower structure about an axis to align the upper structure relative to the lower structure at a predetermined relative angle; (c) in response to the upper structure having been aligned relative to the lower structure at the predetermined relative angle, signaling that alignment has been achieved; and (d) causing rotation of the upper structure to stop when alignment has been achieved and being non-responsive to further detection of the operator command during and for a predetermined period of time after said signaling. Also, a tracked vehicle comprising an ECU that executes the above process.

A work vehicle includes an engine and a transmission assembly having a variator, a gear arrangement, and an electric machine operably connected to the engine and to the variator to provide rotational power to the variator. The transmission assembly selectively transfers power from one or both of the engine and the electric machine to an output shaft to drive ground engaging elements of the work vehicle. A traction control unit controls a speed or torque output of the electric machine to provide traction control for the work vehicle, with the traction control unit operating to receive inputs on a commanded ground speed and an actual ground speed of the work vehicle, compare the commanded ground speed to the actual ground speed and, when the commanded ground speed exceeds the actual ground speed by a threshold amount, reduce the speed or torque output of the electric machine, thereby providing traction control for the ground engaging elements.

A working machine includes a controller that performs shift shock reduction control when shift-down switching from a second state to a first state, in which a motor speed can be increased up to a first maximum speed lower than a second maximum speed available in the second state, is performed. The controller includes a first processor configured to, based on a drop amount that is a difference between target and actual numbers of revolutions of a prime mover, compute a first reduction amount for reducing an amount of hydraulic fluid supply from a traveling pump to a traveling motor, a second processor configured to compute a second reduction amount based on a degree of straight traveling of a machine body, and a reduction controller configured to, based on the first or second reduction amount, whichever is larger in absolute value, perform the shift shock reduction control.

A working machine includes: a machine body provided thereon with a traveling pump and a traveling motor; a traveling change-over valve shiftable between a first state where a rotation speed of the traveling motor is set to a first speed and a second state where the rotation speed is set to a second speed; an actuation valve operable to control a flow of operation fluid to an operation valve that changes a pressure of operation fluid to be applied to the traveling pump according to operation of an operation member; and a controller to perform a shock-mitigation control for reducing an opening degree of the actuation valve when the traveling change-over valve is shifted from the first state to the second state. The controller determines a reduction amount of the opening degree of the actuation valve reduced by the shock-mitigation control, based on a straight-traveling degree of the machine body.

An attachment is attached to an upper turning body. During a normal operation, a drive means drives the attachment according to an input of an operator to a manipulation device. A sensor detects a motion of an excavator. Based on an output of the sensor, the slip suppression unit detects slip of a traveling body in an extension direction of the attachment and corrects an operation of the attachment performed by the drive means.