A series train of symmetrical dual rod-end double-action hydraulic cylinders with a cross sectional area in a series of powers of 2. The cylinders have corresponding computer controlled valves. The cylinders are switchable into three states. One state of shortcutting 2 fluid ports, another state of driving towards each opposite direction of reciprocation and the third state of idling. In the cylinder train all same polarity ports of the valve assembly are connected by hoses or pipes to align towards the same orientation to enable synchronous reciprocal motion and train power output.

A fluidic control system (1) for controlling a vehicle, which includes a controller (2) and a closed fluidic circuit. The circuit includes a pump (3) for pressurizing fluid in the circuit, valve means (40, 50, 60), an actuator (4, 5, 6) and a precharge accumulator (7). The valve means (40, 50, 60) is fluidly connected to the inlet and outlet of the pump (3) and the actuator (4, 6) is fluidly connected to the valve means (40, 50, 60) for selectively receiving pressurized fluid therefrom. The precharge accumulator (7) includes a movable member (73, FIG. 2) that describes a variable volume (71) fluidly connected to the circuit between the valve means (40, 50, 60) and the inlet of the pump (3). The system (1) also includes a sensor (70) for determining the position of the movable member (73) for estimating the quantity of fluid and/or detecting an abnormal pressure variation within the circuit.

A tillage implement has a frame with a center section and first and second outer wing sections hingedly attached to respective outer ends of the center section. Controlling a pressure in a secondary side of a hydraulic circuit enables adjustment of the downward pressure precharge provided by hydraulic cylinders based on a desired stiffness of the implement. Flow from a hydraulic supply through a pressure-reducing valve puts the downward pressure precharge on gauge wheels. Once this desired downward pressure precharge has been achieved, flow from the hydraulic supply is shut off and a check valve holds the pressure such that the hydraulic cylinders hold the gauge wheels in the desired position.

A fluidic control system (1) for controlling a vehicle, which includes a controller (2) and a closed fluidic circuit. The circuit includes a pump (3) for pressurizing fluid in the circuit, valve means (40, 50, 60), an actuator (4, 5, 6) and a precharge accumulator (7). The valve means (40, 50, 60) is fluidly connected to the inlet and outlet of the pump (3) and the actuator (4, 6) is fluidly connected to the valve means (40, 50, 60) for selectively receiving pressurized fluid therefrom. The precharge accumulator (7) includes a movable member (73, FIG. 2) that describes a variable volume (71) fluidly connected to the circuit between the valve means (40, 50, 60) and the inlet of the pump (3). The system (1) also includes a sensor (70) for determining the position of the movable member (73) for estimating the quantity of fluid and/or detecting an abnormal pressure variation within the circuit.

Disclosed is a hydraulic control valve assembly of automatic steering system for agricultural machine including a proportional directional valve (3). A balancing valve (1) is arranged between the proportional directional valve (3) and the steering cylinder. A first shuttle valve (2) is arranged between the proportional directional valve (3) and the balancing valve (1). The first shuttle valve (2) is positioned on one side of the proportional directional valve (3). An overflow valve (4) is positioned on another side of the proportional directional valve (3). The overflow valve (4) is connected to a second shuttle valve (6) and a logic valve (5) respectively. The hydraulic control valve assembly has a large control power, a rapid response, and is more suitable for the autonomous navigation operation of agricultural machine. Moreover, the system saves more energy, such that the autonomous navigation operation of agricultural machine is more stable.

An connecting structure of an electromagnetic valve includes: a first connecting structure body that prohibits a relative movement between a hydraulic pressure circuit body and an electromagnetic valve in an axis line direction; a second connecting structure body that prohibits a relative movement therebetween in a plane orthogonal to the axis line direction; a third connecting structure body that prohibits a relative rotation about the axis therebetween; and a connection body that is prohibited from moving relatively to the hydraulic pressure circuit body, wherein the first connecting structure body includes a first target connection tool that is provided in an accommodation body and a first connection tool that locks the first target connection tool in the axis line direction at a wall portion constituting an accommodation space.

An actuation pressure to actuate one or more hydraulic actuators may be determined based on a load on the one or more hydraulic actuators of a robotic device. Based on the determined actuation pressure, a pressure rail from among a set of pressure rails at respective pressures may be selected. One or more valves may connect the selected pressure rail to a metering valve. The hydraulic drive system may operate in a discrete mode in which the metering valve opens such that hydraulic fluid flows from the selected pressure rail through the metering valve to the one or more hydraulic actuators at approximately the supply pressure. Responsive to a control state of the robotic device, the hydraulic drive system may operate in a continuous mode in which the metering valve throttles the hydraulic fluid such that the supply pressure is reduced to the determined actuation pressure.

The present invention relates to a subsea hydraulic control device (10) for hydraulically controlling a subsea module (2). The control device (10) comprises a hydraulic distribution unit (12) with a valve unit (13) and a manifold unit (50), where hydraulic fluid lines are provided in the valve unit (13) and in the manifold unit (50). The hydraulic distribution unit (12) comprises a low pressure hydraulic input port (21) connectable to a low pressure fluid source (LP) and connected to a low pressure fluid line (22) within the hydraulic distribution unit (12), a high pressure hydraulic input port (31) connectable to a high pressure fluid source (HP) and connected to a high pressure fluid line (32) within the hydraulic distribution unit (12), a return port (41) connectable to a return fluid reservoir (R) and connected to a return fluid line (42) within the hydraulic distribution unit (12) and a number of hydraulic output ports (24, 34) connectable to subsea actuators (A) of the subsea module (2). A section of the low pressure fluid line (22) is provided as a first fluid bore (B22) in the manifold unit (50) and a section of the high pressure fluid line (32) is provided as a second fluid bore (B32) in the manifold unit (50). The configuration of the respective bores (B22, B32) in the manifold unit (50) is determining which of the output ports (24, 34) being a low pressure output port (24) connected to the low pressure fluid line (22) and which of the output ports (24, 34) being a high pressure output port (34) connected to the high pressure fluid line (32).

An actuation pressure to actuate one or more hydraulic actuators may be determined based on a load on the one or more hydraulic actuators of a robotic device. Based on the determined actuation pressure, a pressure rail from among a set of pressure rails at respective pressures may be selected. One or more valves may connect the selected pressure rail to a metering valve. The hydraulic drive system may operate in a discrete mode in which the metering valve opens such that hydraulic fluid flows from the selected pressure rail through the metering valve to the one or more hydraulic actuators at approximately the supply pressure. Responsive to a control state of the robotic device, the hydraulic drive system may operate in a continuous mode in which the metering valve throttles the hydraulic fluid such that the supply pressure is reduced to the determined actuation pressure.

A control device generates an operation signal for controlling a pressure of hydraulic oil on a downstream side of the swing motor in a hydraulic device based on an azimuth direction, a swing speed, and a target stopping azimuth direction of a swing body during braking of a swing motor.