A control device for controlling a hydraulic consumer (2), such as a working cylinder, has at least one control valve (18) having a control spool (20). Control spool (20) is guided in a valve housing (22) in a longitudinally movable manner and is actuated by an electric motor (24). Electric motor (24) can be controlled by control electronics (MC), which receive input signals from a sensor device (58, 60, 62) detecting at least one operating state of the consumer (2).

In a cylinder drive device, a throttle valve and a second check valve are provided between a switch valve and a first cylinder chamber of a fluid pressure cylinder. The cylinder drive device has a flow channel unit which is interposed between a manifold and the switch valve, which allows communication between the throttle valve and the second check valve and switch valve, and which communicates with a plurality of holes in the manifold to allow a fluid to flow to the switch valve.

An aircraft assembly having: a first part; a second part, the second part being movably mounted with respect to the first part; an electro-hydraulic actuator coupled between the second part and a first anchor point, the actuator comprising a cylinder defining a bore and a piston and rod assembly slidably mounted within the bore and an active chamber within which an increase in fluid pressure causes the actuator to change during a first phase between first and second extension states to move the second part relative to the first part. The electro-hydraulic actuator further includes a hydraulic fluid supply circuit comprising a piezo-electric pump operable to supply pressurised fluid to the active chamber to change the actuator between first and second extension states.

In a flow rate controller and a drive device, a housing is provided therein with a first flow passage, a second flow passage adjacent to the first flow passage, a first throttle valve provided to the first flow passage, and a second throttle valve provided to the second flow passage. A pilot check valve is provided to the second flow passage and is connected in series to the second throttle valve. A pilot air flow passage communicates with a pilot port of the pilot check valve for supplying and discharging pilot air, and a third throttle valve is provided to the pilot air flow passage. In response to the pressure of the pilot air, the pilot check valve switches between a state in which the passage of exhaust air discharged from an air cylinder is permitted and a state in which passage of the exhaust air is prevented.

An example valve includes a housing, a sleeve disposed within the housing and having a first end and a second end opposite the first end, and the sleeve includes a plurality of sleeve protrusions at the first end and a plurality of fluid flow channels are formed between adjacent sleeve protrusions, a seal carrier disposed within the sleeve and having a carrier protrusion that extends from the second end of the sleeve and abuts against an interior surface of the housing, and an end cap mounted to the housing such that the plurality of sleeve protrusions abut against the end cap.

In a fluid circuit for an air cylinder connected to a switching valve provided with exhaust ports, a head-side pressure chamber is connected to the switching valve by a first pipe, and a rod-side pressure chamber is connected to the switching valve by a second pipe. A first restrictor is disposed at a connection point between the first pipe and the switching valve or in the vicinity of a first output port of the switching valve, and a second restrictor is disposed at a connection point between the second pipe and the switching valve or in the vicinity of a second output port of the switching valve.

An aircraft assembly having: a first part; a second part, the second part being movably mounted with respect to the first part; an electro-hydraulic actuator coupled between the second part and a first anchor point, the actuator comprising a cylinder defining a bore and a piston and rod assembly slidably mounted within the bore and an active chamber within which an increase in fluid pressure causes the actuator to change during a first phase between first and second extension states to move the second part relative to the first part. The electro-hydraulic actuator further includes a hydraulic fluid supply circuit comprising a piezo-electric pump operable to supply pressurised fluid to the active chamber to change the actuator between first and second extension states.

Methods can comprise charging a first hydraulic device of a first hydraulic circuit with a first quantity of hydraulic fluid from a hydraulic fluid source. The methods can further comprise pressurizing a control segment and locking the first quantity of hydraulic fluid from exiting the first hydraulic circuit in response to hydraulic pressure within the control segment. The methods can also include unlocking the first quantity of hydraulic fluid to permit exiting of the first quantity of hydraulic fluid from the first hydraulic device in response to dropping the hydraulic pressure within the control segment after a delay. Hydraulic apparatus can comprise a normally open hydraulic pilot operated control valve that can be configured to hydraulically lock a first hydraulic device in response to a hydraulic pressure within a control segment rising to greater than or equal to an actuation pressure.

Methods can comprise charging a first hydraulic device of a first hydraulic circuit with a first quantity of hydraulic fluid from a hydraulic fluid source. The methods can further comprise pressurizing a control segment and locking the first quantity of hydraulic fluid from exiting the first hydraulic circuit in response to hydraulic pressure within the control segment. The methods can also include unlocking the first quantity of hydraulic fluid to permit exiting of the first quantity of hydraulic fluid from the first hydraulic device in response to dropping the hydraulic pressure within the control segment after a delay. Hydraulic apparatus can comprise a normally open hydraulic pilot operated control valve that can be configured to hydraulically lock a first hydraulic device in response to a hydraulic pressure within a control segment rising to greater than or equal to an actuation pressure.

The present invention provides an improved high-low hydraulic system for compacting machinery, such as balers, horizontal balers, compactors, transfer station compactors, and the like. The high-low hydraulic system comprises at least one double rotary pump, a plurality of directional control valves, a pilot-operated back pressure reducing valve, a flow control valve, a plurality of one-way valves, and a plurality of pressure switches. The high-low hydraulic system may be regenerative or non-regenerative and provides many advantages over conventional hydraulic systems. Such advantages include greater system efficiency due to a reduced back pressure during the time of the retraction stroke and clever flow sequencing, mitigation of hydraulic shocks at the beginning and end of compaction and retraction strokes, and reduced cycle time of the cylinder during operation due to the concurrent filling of the rod end side during decompression of the blind end side after the compaction stroke. Moreover, the present high-low hydraulic system allows for the cylinder to operate at three or more independent speeds. Additionally, the present high-low hydraulic system may also comprise an accumulator and pressure transducer that further assist with substantially maintaining a predetermined hydraulic pressure on the blind end side after the completion of the compaction stroke.