An electrohydraulic control circuit includes a hydraulically-operated drive assembly and an emergency valve. The hydraulically-operated drive assembly includes an electrically-actuated proportional valve and hydraulic operating lines. The proportional valve is connected to the hydraulic operating lines for actuation of the drive assembly in a normal operation mode. The proportional valve is also connected to a pressure supply line and to a return line. The emergency valve is connected to the hydraulic operating lines for actuation of the drive assembly in an emergency operation mode. In the emergency operation mode, the emergency valve is actuated via an emergency operating unit.

An electrohydraulic control circuit includes a hydraulically-operated drive assembly and an emergency valve. The hydraulically-operated drive assembly includes an electrically-actuated proportional valve and hydraulic operating lines. The proportional valve is connected to the hydraulic operating lines for actuation of the drive assembly in a normal operation mode. The proportional valve is also connected to a pressure supply line and to a return line. The emergency valve is connected to the hydraulic operating lines for actuation of the drive assembly in an emergency operation mode. In the emergency operation mode, the emergency valve is actuated via an emergency operating unit.

A robotic joint that includes a hydraulic actuator. The hydraulic actuator includes a hollow tube that has a first opening at a first end of the hollow tube and that has a second opening at a second end of the hollow tube. The hollow tube contains hydraulic fluid. A moveable magnet moves within hollow tube as a result of a magnetic field within the hollow tube. A magnetic field source located outside the hollow tube creates the magnetic field within the hollow tube. When the moveable magnet moves to the first end of the hollow tube, a first piston pushes hydraulic fluid out of the first opening. When the moveable magnet moves to the second end of the hollow tube a second piston pushes hydraulic fluid out of the second opening.

A robotic joint that includes a hydraulic actuator. The hydraulic actuator includes a hollow tube that has a first opening at a first end of the hollow tube and that has a second opening at a second end of the hollow tube. The hollow tube contains hydraulic fluid. A moveable magnet moves within hollow tube as a result of a magnetic field within the hollow tube. A magnetic field source located outside the hollow tube creates the magnetic field within the hollow tube. When the moveable magnet moves to the first end of the hollow tube, a first piston pushes hydraulic fluid out of the first opening. When the moveable magnet moves to the second end of the hollow tube a second piston pushes hydraulic fluid out of the second opening.

A hydraulic system including a supply line, an implement-based control valve, an override valve supported by the implement, and a bypass line. The control valve is fluidly coupled to the supply line and configured to regulate a flow of pressurized hydraulic fluid supplied through a downstream actuator line to a hydraulic actuator of the implement. The override valve is fluidly coupled to the actuator line downstream of the control valve and includes a supply position at which the flow of pressurized hydraulic fluid from the control valve passes through the override valve to the hydraulic actuator. The override valve is actuatable to at least one override position at which the flow of pressurized hydraulic fluid from the control valve is cut-off. The bypass line is fluidly coupled between the supply line and the override valve such that a portion of the pressurized hydraulic fluid flows to the hydraulic actuator.

A hydraulic system including a supply line, an implement-based control valve, an override valve supported by the implement, and a bypass line. The control valve is fluidly coupled to the supply line and configured to regulate a flow of pressurized hydraulic fluid supplied through a downstream actuator line to a hydraulic actuator of the implement. The override valve is fluidly coupled to the actuator line downstream of the control valve and includes a supply position at which the flow of pressurized hydraulic fluid from the control valve passes through the override valve to the hydraulic actuator. The override valve is actuatable to at least one override position at which the flow of pressurized hydraulic fluid from the control valve is cut-off. The bypass line is fluidly coupled between the supply line and the override valve such that a portion of the pressurized hydraulic fluid flows to the hydraulic actuator.

A system for remotely controlling hydraulic component of an agricultural implement towed by a work vehicle may include a vehicle-based valve assembly that selectively supplies hydraulic fluid to one or more supply lines of the implement. Specifically, a first supply line may be fluidly coupled to an implement-based valve assembly that regulates the supply of hydraulic fluid to a hydraulic actuator through a first actuator line. A second supply line may be fluidly coupled to the first actuator line downstream of the implement-based valve assembly such that when a user provides a control input at a remote interface, the vehicle-based valve assembly may instead regulate the supply of hydraulic fluid to the actuator. The supply of the hydraulic fluid through the supply lines may additionally be controlled by first and second override valves fluidly coupled to the first and second supply lines, respectively.

A system for remotely controlling hydraulic component of an agricultural implement towed by a work vehicle may include a vehicle-based valve assembly that selectively supplies hydraulic fluid to one or more supply lines of the implement. Specifically, a first supply line may be fluidly coupled to an implement-based valve assembly that regulates the supply of hydraulic fluid to a hydraulic actuator through a first actuator line. A second supply line may be fluidly coupled to the first actuator line downstream of the implement-based valve assembly such that when a user provides a control input at a remote interface, the vehicle-based valve assembly may instead regulate the supply of hydraulic fluid to the actuator. The supply of the hydraulic fluid through the supply lines may additionally be controlled by first and second override valves fluidly coupled to the first and second supply lines, respectively.

This hydraulic system is provided with: a hydraulic pump; a pilot-type control valve; an electromagnetic proportional valve; a controller; and a pilot pressure switching unit which is capable of switching the electromagnetic proportional valve supply pressure to a first pressure during a normal operation, or to a second pressure lower than the first pressure. The control valve is provided with a bleed-off passage, and is capable of controlling the operating oil pressure supplied to the actuator, according to the opening area thereof. During an emergency operation, the electromagnetic proportional valve supply pressure is switched from the first pressure to the second pressure, the electromagnetic proportional valve is brought into a fully opened state, and the operating oil discharge amount from the hydraulic pump increases and decreases, and the operating oil pressure increases and decreases, and thus the operating speed of the actuator is controlled.

A servo valve is provided with a first elastic portion, a second elastic portion, and a connecting portion. The first elastic portion extends in an X direction inside a valve body and has a first elastic force exerted on a movable element toward an X2 direction. The second elastic portion extends in the X direction inside the valve body and has a second elastic force exerted on the movable element toward an X1 direction. The connecting portion is connected to the first elastic portion and the second elastic portion inside the valve body, and is in abutment against a step portion of the valve body and a spool of the movable element at a neutral position of the movable element.