A pressure multiplier having a cylinder assembly, a command device, and an electronic control unit is provided. The electronic control unit is configured to obtain a switching signal to be provided to the command device from a compression curve which, knowing pressure of a fluid entering the pressure multiplier, binds a pressure increase of the fluid exiting the pressure multiplier with a switching frequency of a piston of the cylinder assembly.

A pneumatic volume booster to amplify a control pressure output signal can include a pneumatic control outlet for attachment to a pneumatic working chamber of the pneumatic actuator; a pneumatic aeration inlet configured to receive the pneumatic control pressure signal from the position controller, a pneumatic amplification inlet configured to receive a constant pneumatic air amplification signal, a pneumatic de-aeration connection from the control outlet to a pressure sink configured to aerate the control actuator, a deaerator seat-valve separating and/or opening the pneumatic de-aeration connection, a pneumatic aeration connection between the first aeration inlet and the control outlet; an aerator seat-valve separating and/or opening the pneumatic aeration connection, a pneumatic amplification connection between the amplification inlet and the control outlet; an amplification seat-valve separating and/or opening the pneumatic amplification connection; and a mechanical seat-valve-operator for commonly operating the de-aeration seat-valve, the first aerator seat-valve and the amplification seat-valve.

An injection molding system, water jet cutting machine or other industrial system has a synthetically controlled variable displacement fluid working machine which outputs hydraulic fluid to one or more fluid consumers, such as rams or hydraulic motors, through hydraulically stiff fluid retaining volumes and receives hydraulic fluid back from one or more fluid consumers through the same or other said hydraulically stiff fluid retaining volumes. Individual piston cylinder assemblies can be allocated to different outputs. There may be no valve between the machine and the consumers. A working chamber of the machine can be caused to undergo a motoring cycle to enable the machine to output more power than is received from a motor driving the machine. An accumulator can be used to provide a source of hydraulic compliance. The machine can be controlled using pressure control, flow control, feed forward control or variable power/variable power limit control.

A pneumatic unit for a hydropneumatic pressure booster has a system line that leads from a compressed air inlet to a compressed air outlet. A bypass line runs parallel to the system line and it is connected to the system line via first and second compressed air switches. A compressed air reservoir is connected in the bypass line, and a pressure intensifier is connected in the region between the first compressed air switch and the compressed air reservoir. The pneumatic unit makes available to the pressure booster a sufficiently high pneumatic pressure for carrying out at least one operational step of a connected hydraulic tool, even in the case of a pressure decrease or pressure failure in the supplying pneumatic line. For that purpose, the second compressed air switch is configured for switching the compressed air flow between the system line and the bypass line.

An indirect hydraulic load hierarchical control system and method for a wave energy device includes a first hydraulic cylinder group, a second hydraulic cylinder group, a third hydraulic cylinder group, a high-pressure energy accumulator group, a pressure detection control module, a first hydraulic power generator set, a second hydraulic power generator set and a third hydraulic power generator set. A detection end of the pressure detection control module is used for acquiring an internal pressure of the high-pressure energy accumulator group, comparing the internal pressure with a preset pressure level, and respectively controlling the on-off of reversing valves and electromagnetic valves according to a comparison result. The present invention has the beneficial effects that all hydraulic loads can be automatically loaded or automatically unloaded, so that the wave energy device operates in a full load state or in an optimal energy conversion efficiency state.

The invention relates to an apparatus for the energy-optimized hydraulic control of at least one double-action working cylinder of a work machine comprising a hydraulic pressure transducer which is hydraulically connected to a first piston surface of the working cylinder, to a second piston surface of the working cylinder and to at least one pressure accumulator, wherein the pressure transducer is configured such that the hydraulic energy of a high-pressure volume flow conveyed by the first piston surface to the pressure transducer can be stored completely or at least partially by the at least one connected pressure accumulator and such that the cylinder chamber of the second piston surface of the working cylinder can be filled with a low-pressure volume flow by the pressure transducer.

In various embodiments, fluid conduits such as high pressure hoses deployed in-between two sea-fairing vessels may be released during an emergency by using a rapid release emergency disconnect system as described herein, where the rapid release emergency disconnect system may engage with a hanger such as an industry standard frac hanger and be used in-line with fluid conduits such as high-pressure lines. Various skid embodiments are described which can be configured to interface with one or more of the described rapid release emergency disconnect systems.

A double-loop control system with a single hydraulic motor relates to a technical field of hydraulic transmission control, including a hydraulic motor (1), a positive control loop (2), a negative control loop (3), a hydraulic pump (4), an accumulator (5), and an oil tank, wherein the hydraulic motor (1) adopts a unique thrust structure with four inlet/outlet ports; the positive control loop (2) and the negative control loop (3) independently control the hydraulic motor (1), wherein the positive control loop (2) and the negative control loop (3) drive together or only one drives; or braking kinetic energy and potential energy of loads are stored in the accumulator (5) for energy recovery. The present invention uses only one hydraulic motor for satisfying different work conditions and different load driving requirements with advantages such as simple structure, high system reliability and high energy efficiency.

A fluid circuit includes a pressure fluid source, a switching valve, and a cylinder device having first and second chambers and partitioned by a piston. A first accumulator is configured to communicate with the second chamber when pressure fluid is supplied to the first chamber and to accumulate part of the pressure fluid from the second chamber. A pressure booster is connected in hydraulically parallel to the first accumulator, the pressure booster communicative with the second chamber when the pressure fluid is supplied to the first chamber to boost pressure of the pressure fluid by using part of the pressure fluid from the second chamber. A second accumulator accumulates the pressure fluid whose pressure is boosted by the pressure booster.

A hydraulic system that includes a rotating group with a plurality of fluid chambers and a plurality of valve sets that valve a corresponding one of the fluid chambers is disclosed. The hydraulic system may function as a hydraulic transformer. The hydraulic system may transfer energy between a high pressure fluid supply (e.g., from a pump), an accumulator, a hydraulic component (e.g., a hydraulic cylinder, a hydraulic motor, and/or a hydraulic pump-motor), and/or an input/output shaft. The hydraulic system may include a single rotating group with a common axis. Each of the valve sets may include a first valve that fluidly connects to the pump, a second valve that fluidly connects to a tank, a third valve that fluidly connects to the accumulator, and a fourth valve that fluidly connects to the hydraulic component. The valves may have a valving period set to less than half or one-third of a rotational period of the rotating group. The valves may have a frequency of greater than 100 Hertz and may be digitally controlled.