A calibration system is disclosed. The calibration system may include a sensor configured to measure a fluid level in a fluid tank of a machine, an actuator that, when actuated, affects a level of the machine, and a controller. The controller may be configured to: command actuation of the actuator at a current; receive, from the sensor and after commanding actuation of the actuator, information identifying the fluid level in the fluid tank; determine, based on the information identifying the fluid level in the fluid tank, whether there is a change to the fluid level in the fluid tank; and set an initiation current for the actuator at the current based on determining whether there is the change to the fluid level in the fluid tank.

A work vehicle including: a first link having one end portion supported by a vehicle body so as to be pivotable; a second link having one end portion pivotally coupled to the other end portion of the first link so as to be pivotable, and another end portion that supports a travel wheel; a first hydraulic cylinder capable of changing a swing posture of the first link; and a second hydraulic cylinder capable of changing a swing posture of the second link relative to the first link. The action of the first hydraulic cylinder is controlled such that a swing position of the first link is located at a target position, based on the result of detection performed by a position detection sensor, and the action of the second hydraulic cylinder is controlled such that thrust has a target value, based on the results of detection performed by pressure sensors.

A milling machine is disclosed. The milling machine may have a frame, first and second tracks connected to a first end of the frame, a third track connected to a second end of the frame, and a milling drum attached to the frame. The milling machine may have first, second, and third actuators connecting the frame and the first, second, and third tracks, respectively. Each actuator may adjust a height of the frame relative to a respective one of the first, second, and third tracks. The milling machine may include a damper assembly attached to each of the first and second actuators. The damper assembly may have an accumulator connected to a respective one of the first and second actuators and a control valve for controlling a flow of fluid between the accumulator and the respective one of the first and second actuators.

A motor grader having ride control for dampening machine bounce using a DCM assembly rotatably coupled to and suspended from a frame of the motor grader is disclosed. Each lift cylinder for the DCM may have an associated ride control circuit with an accumulator, a ride control conduit fluidly connected to a carry end of the lift cylinder and having a flow restriction element, and a ride control accumulator valve fluidly connected to the accumulator and the ride control conduit and operable to either block or allow fluid communication between the carry end and the accumulator through the flow restriction element. Each rid control circuit may also include a head end valve fluidly connected to between the head end of the lift cylinder and a low pressure fluid reservoir and operable to block or allow fluid communication between the head end and the low pressure fluid reservoir.

The system includes an oscillating chassis (10) suitable for being linked to an axle (6) of a vehicle (1); two cylinders (11, 12), referred to as compensation cylinders, linking the oscillating chassis (10) to the main chassis (5) of the vehicle; a proportional distributor or valve (13) to which the compensation cylinders (11, 12) are connected; an axle tilt detector (14) detecting tilt of the axle (6) resulting in the wheel (2) of the vehicle (I) opposite the arm (3) being raised; and a computer (15) connected to this tilt detector (14) and to piloted actuation device (30) for actuating the valve-slide of the proportional distributor (13); in the event of the axle (6) tilting in a manner that tends to raise the wheel (2) situated on the side opposite the arm (3), the computer (15) controls these actuation device (30) in such a way as to control the valve-slide of the proportional valve (13). The vehicle (1) is equipped with the stabilization system.

A method for forming hydraulic oil passages for hydraulic actuators according to an aspect of the present invention includes: forming a valve block mount surface including first and second regions on an outer surface of a housing; collecting valves for hydraulic actuators belonging to a main function group to a main function valve block that is mountable directly or indirectly on the first region; collecting valves for hydraulic actuators belonging to an additional function group to an additional function valve block that is mountable directly or indirectly on the second region; and mounting the valve blocks on corresponding regions of the valve block mount surface, and thereby, the hydraulic actuators to be mounted are fluidly connected to each other so that the hydraulic actuators are operable by using hydraulic oil from a common oil source.

An auto-leveling drive axle device for a wheel tractor, and leveling method. The device comprises a transmission device and a leveling device. The device of the present invention changes only a vertical position of a drive axle with respect to a wheel, and a wheel shaft distance and wheel center spacing are not changed, thus improving traveling stability of a vehicle.

A ride control system for a power machine having a lift arm movably coupled to a frame. A hydraulic cylinder configured to selectively control movement of the lift arm relative to the frame. An accumulator is in selective communication with a first end of the hydraulic cylinder. A pressure sensor communicates a signal indicative of a hydraulic pressure at a first end of the hydraulic cylinder. A ride control circuit allows selective communication between the accumulator and the first end of the hydraulic cylinder. A controller receives the signal from the pressure sensor, and prevents communication between the accumulator and the first end of the hydraulic cylinder until the signal from the pressure sensor indicates a pressure below an initial pressure threshold value.

An oil channel that connects a right damper and a left damper includes a switching valve arranged between a right oil channel ER and a left oil channel EL. The switching valve includes a valve main body in which a first switching channel is formed for connecting the right oil channel ER and the left oil channel EL. The valve main body is rotatable to a first position where the first switching channel connects the right oil channel ER and the left oil channel EL to each other and to a second position different from the first position. According to this damping system, it is possible to adjust oil flow in the oil channel by performing a simple operation for the switching valve.

A machine comprising a frame including a front-right portion, a front-left portion, a rear-right portion, and a rear-left portion. The machine includes a first jack coupled with the front-right portion for raising or lowering the front-right portion, a second jack coupled with the front-left portion for raising or lowering the front-left portion, a third jack coupled with the rear-right portion for raising or lowering the rear-right portion, and a fourth jack coupled with the rear-left portion for raising or lowering the rear-left portion. The machine includes a front jack leveling system operatively coupled with the first jack and the second jack. The front jack leveling system controls the first jack and the second jack such that a first movement of the first jack in a first direction corresponds to a second movement of the second jack in a second direction that is opposite from the first direction.