A control system includes a closing unit including a tank including a usable volume of the control system, at least one primary pump configured to pump hydraulic fluid from the usable volume of the tank, a plurality of valves, and a first pressure transducer disposed between the at least one primary pump and at least one valve of the plurality of valves. The at least one primary pump, the pressure transducer, and the at least one valve of the plurality of valves are hydraulically connected with the tank. The first pressure transducer manages a start-stop operation of the at least one primary pump. Hydraulic fluid within the control system has a predetermined static pressure. The at least one pump is powered by an electric energy source.

A fail-safe actuation system comprising an actuator having first and second chambers, a working circuit with a motor/pump device configured to actuate the actuator in an operative state, and a safety circuit configured to move the actuator into the safety position in a failure state, the safety circuit having a tank that holds pressurized fluid and that, in the failure state, is automatically connected to the first chamber via a switching valve, and having a drain valve that, in the failure state, is moved into a through-flow position in order to drain fluid out of the second chamber, the safety circuit configured such that, in the operative state, an inflow into the actuator—in a manner that is decoupled from the tank—is established by the working circuit, and, in the failure state, an inflow from the tank into the first chamber—in a manner that is completely decoupled from the working circuit—is created by the safety circuit, whereby a short-circuit fluid connection is provided between the first and second chambers that, in the failure state, is through-connected in order to generate a short-circuit flow between the first and second chambers.

A system and method configured to direct the braking energy from a high-pressure port at the motor side of a hydraulic circuit to emergency steering, braking, accumulator(s) charging, and/or various work functions. The system and method are also configured to return hydraulic fluid back to the same high-pressure port when the motor is running as a pump.

A power transmission control method and device for a crane and the crane includes setting the maximum working displacement of a secondary element corresponding to each gear of the crane; determining the current gear state and specific gear of the crane; determining the working mode of the secondary element from the gear state, and setting the maximum allowable displacement of the secondary element as the maximum working displacement corresponding to the specific gear. In the power transmission control method and device for the crane and the crane of the present invention, the maximum displacement of the secondary element is controlled for various gears, which can reduce power impact. A buffer mode is added to avoid influence on a vehicle due to loss of instant power generated at the moment of energy release completion and avoid vehicle jitter due to instable power resulting from the vehicle at low speed or a system suddenly disconnected.

A hydraulic adjusting device, in particular for use in a power plant and/or a wind power plant, includes a double-acting adjusting cylinder that has an adjusting function for a working operation and for a special operation. The double-acting adjusting cylinder is configured to be pressurized with a working pressure medium. In order to satisfy the adjusting function in the special operation, the double-acting adjusting cylinder is further configured to be connected to a pressure medium reservoir that has a pressurized gas isolated from the working pressure medium. The adjusting cylinder has a working chamber configured for the adjusting function of the special operation, the piston area of which is coupled to a piston arrangement of the adjusting cylinder that is configured for the working operation or is configured to be coupled to the piston arrangement.

An electric-powered fail-safe actuator for use with a valve, where the actuator stores potential energy for conversion to kinetic energy to close or open the valve to the fail-safe position.

Universal control circuitry for an electro-hydraulic valve actuator system includes logic gate circuitry to control one or more of a closing solenoid valve, an opening solenoid valve, an emergency shutdown solenoid valve, and a hydraulic fluid pump motor to route hydraulic fluid through a hydraulic circuit to actuate a valve via a hydraulic actuator according to received commands. The universal control circuitry is configured to control operation for multiple different configurations of a hydraulic valve actuator system including double-acting configurations, single-acting spring-to-open configurations, and single-acting spring-to-close configurations, each with or without an emergency shutdown arrangement (which may be configured to trip based on an external shutdown input alone or in combination with a local system power failure), a hydraulic accumulator, and maintained or momentary input commands.

A system and method configured to direct the braking energy from a high-pressure port at the motor side of a hydraulic circuit to emergency steering, braking, accumulator(s) charging, and/or various work functions. The system and method are also configured to return hydraulic fluid back to the same high-pressure port when the motor is running as a pump.

A device for maintaining a hydraulic supply of a utility vehicle includes a hydraulic pump, which is adjustable in terms of its delivery volume via a pressure control inlet, for feeding hydraulic fluid to a hydraulic circuit, a pressure accumulator that can be charged from the hydraulic circuit via a check valve, a pressure connection between the hydraulic circuit and the pressure control inlet of the hydraulic pump being producible via a sensor line by means of a charging valve, and a supply connection between the pressure accumulator and the hydraulic circuit being producible by means of a discharging valve, by virtue of the check valve being bypassed.

A system and method configured to direct the braking energy from a high-pressure port at the motor side of a hydraulic circuit to emergency steering, braking, accumulator(s) charging, and/or various work functions. The system and method are also configured to return hydraulic fluid back to the same high-pressure port when the motor is running as a pump.