A fluid pressure valve according to an embodiment of the present invention is applicable to a fluid pressure servo mechanism. The fluid pressure valve includes a housing having a housing member, the housing member being formed integrally so as to have a first port, a second port, and a flow path connecting between the first port and the second port.

A valve, which is characterized in that between a neutral position (38) of a control spool (STS) and one of its end positions (34, 42) a regeneration position (36) is provided. In the regeneration position, two utility ports (A, B) are interconnected in a fluid-conveying manner, or a floating position (40) is provided, in which these utility ports (A, B) are interconnected in a fluid-conveying manner. A further valve is characterized in that by a further motion of the control spool (STS) in the same direction, as that, in which a fluid connection is established between the utility ports (A, B) starting from the neutral position (38), this fluid connection is interrupted.

An agricultural harvester includes a controller configured to receive at least one wing angle signal indicative of an angle at least one wing with respect to a center section of a header. The controller is also configured to receive a wing height position signal indicative of a distance between the at least one wing and a soil surface, determine whether the angle of the at least one wing exceeds an angle limit threshold based at least in part on the wing angle signal, and output a tilt signal to a tilt actuator in response to determining the angle of the wing exceeds the angle limit threshold. The tilt signal is indicative of instructions to maintain the distance between the at least one wing and the soil surface within a target distance threshold.

An agricultural harvester includes a controller configured to receive at least one wing angle signal indicative of an angle at least one wing with respect to a center section of a header. The controller is also configured to receive a wing height position signal indicative of a distance between the at least one wing and a soil surface, determine whether the angle of the at least one wing exceeds an angle limit threshold based at least in part on the wing angle signal, and output a tilt signal to a tilt actuator in response to determining the angle of the wing exceeds the angle limit threshold. The tilt signal is indicative of instructions to maintain the distance between the at least one wing and the soil surface within a target distance threshold.

A hydraulic system is provided. The hydraulic system may include a fluid pressure source in fluid communication with a supply line, a return line in fluid communication with a tank, a hydraulic function having a workport, a first control valve having a first proportional solenoid, a second control valve having a second proportional solenoid, and a controller. The controller being configured to selectively energize the first proportional solenoid, the second proportional solenoid, or the first proportional solenoid and the second proportional solenoid to control a system pressure differential, defined between the return line and the workport, within a range that is defined by a sum of a first predefined range defined by the first control valve and a second predefined range defined by the second control valve.

A solenoid valve is formed by engaging locking protrusions with engagement holes and thereby joining a valve body and a magnetic cover to each other. A top wall of the magnetic cover is formed by a pair of bent portions that extend from a pair of respective sidewalls of the magnetic cover and that are bent toward the space between the sidewalls. The bent portions are fastened to each other in the width direction Wd by a circuit board spacer (first fastening member), and the circuit board spacer and the valve body are fastened to each other in the axial direction Ld by a connector cover.

A method of controlling an electro-hydraulic actuator (101). An electric voltage applied to the actuator (101) is established by superimposing a control variable with an oscillatory signal. A hydraulic pressure, influenced by the actuator (101), is measured. The oscillatory signal is adapted as a function of the measured hydraulic pressure.

A method of controlling an electro-hydraulic actuator (101). An electric voltage applied to the actuator (101) is established by superimposing a control variable with an oscillatory signal. A hydraulic pressure, influenced by the actuator (101), is measured. The oscillatory signal is adapted as a function of the measured hydraulic pressure.

Electro-hydraulic servo-valves and related methods are disclosed herein. An example electro-hydraulic servo-valve includes an inlet to receive a fluid from a reservoir, a torque motor, a chamber, the fluid to return to the reservoir via the chamber, and a flexure tube coupled to the torque motor. At least a portion of the flexure tube is disposed in the chamber. The flexure tube includes a nozzle to deliver the fluid to an actuator. The example electro-hydraulic servo-valve includes a damper operatively coupled to the flexure tube. The damper is disposed in the chamber.

Electro-hydraulic servo-valves and related methods are disclosed herein. An example electro-hydraulic servo-valve includes an inlet to receive a fluid from a reservoir, a torque motor, a chamber, the fluid to return to the reservoir via the chamber, and a flexure tube coupled to the torque motor. At least a portion of the flexure tube is disposed in the chamber. The flexure tube includes a nozzle to deliver the fluid to an actuator. The example electro-hydraulic servo-valve includes a damper operatively coupled to the flexure tube. The damper is disposed in the chamber.