The energy recovery system includes an inertial fluid container, a low pressure container, a high pressure container, a low pressure valve, and a high pressure valve, a valve flow conduit, and a valve controller. The valve controller switches, in response to a decrease in volume of the fluid chamber, the inertial fluid container between communicating with the low pressure container and the high pressure container, thereby generating inertial forces of the working fluid flowing toward the low pressure container in the inertial fluid container, and causing the working fluid to flow into the high pressure container by the inertial forces. The valve controller sets a switching frequency for the valves to a frequency close to an Nth-order (where N is a natural number) anti-resonance frequency of a flow conduit for the working fluid.

Presented herein are systems and methods that allow for adapting at least one dimension of an accumulator in a hydraulic system when faced with certain dimensional constraints and to vary the compliance or stiffness of an accumulator.

Disclosed is an expansion tank having an internal cavity separated by a flexible diaphragm to form an upper pressurized gas portion and a lower pressurized fluid portion, and an indicator positioned at an upper part of the expansion tank in communication with the contents of the upper pressurized gas portion. The indicator is configured so as to display a first color if the operating conditions are normal in the pressurized gas portion, and a second color if the amount of moisture detected in the pressurized gas portion greater than or equal to a predetermined amount. Further disclosed is a method for detecting whether there is an excessive amount of moisture in a pressurized gas portion of an expansion tank by allowing pressurized gas from the pressurized gas portion to come into contact with the indicator, and viewing the color displayed by the indicator. As such, the tank can be simply visually inspected to determine whether there is a potential failure in the tank.

Disclosed is an expansion tank having an internal cavity separated by a flexible diaphragm to form an upper pressurized gas portion and a lower pressurized fluid portion, and an indicator positioned at an upper part of the expansion tank in communication with the contents of the upper pressurized gas portion. The indicator is configured so as to display a first color if the operating conditions arc normal in the pressurized gas portion, and a second color if the amount of moisture detected in the pressurized gas portion greater than or equal to a predetermined amount. Further disclosed is a method for detecting whether there is an excessive amount of moisture in a pressurized gas portion of an expansion tank by allowing pressurized gas from the pressurized gas portion to come into contact with the indicator, and viewing the color displayed by the indicator. As such, the tank can be simply visually inspected to determine whether there is a potential failure in the tank.

A hydraulic system for an automatic transmission, in particular a dual-clutch transmission, of a motor vehicle. A high-pressure circuit, in which a pressure accumulator, at least one clutch, and gear selectors are connected, and a low-pressure circuit for cooling the clutch. The high-pressure circuit and the low-pressure circuit have at least one hydraulic pump, which can be driven by an electric motor. The hydraulic system also has a control unit, which activates the electric motor of the hydraulic pump when a requirement to charge the pressure accumulator is identified. The high-pressure and low-pressure circuits are connected via a bypass line to an integrated accumulator charging valve, which in a non-charging position fluidically connects the hydraulic pump to the low-pressure circuit and in a charging position fluidically connects the hydraulic pump to the high-pressure circuit.

A liquid seal energy-accumulator and hydraulic system thereof based on liquid-collector and sandwich piston is provided. The liquid seal energy-accumulator includes a piston cylinder (HSG) and a high pressure gas-tank (QTG). When a piston (HS) moves to a top of the piston cylinder, the leaked pressure liquid accumulated on the top of the piston flows into the gas-tank through a gas-liquid-pipe (TD), so as to timely clean up the pressure liquid accumulated on the top of the piston. The pressure liquid collected at the bottom of the gas-tank is increased for upwardly moving a buoy (FT), when the buoy presses a collection-liquid sensor (JYG), a signal is sent for opening an electronically-controlled-valve (DKF), the leaked pressure liquid flows from the liquid leakage pipe (LYG) back to the liquid-container (SYT).

A safety device, comprising a connection point (21) for a pressure accumulator (1) that is connected to a bursting unit (55) at the gas end via the connection point (21), is characterized in that the bursting unit (55) can be triggered by a controllable force element (73) and, in the triggered state, allows the pressure accumulator (1) to be emptied at the gas end.

Disclosed is a landing gear bogie pitch trimmer, comprising a hydraulic actuator for adjusting a pitch of a landing gear bogie, in use, a fluid interface for receiving, from an aircraft hydraulic system external to the landing gear bogie pitch trimmer, hydraulic fluid for use in actuating the hydraulic actuator, and a flow control valve for controlling flow of the hydraulic fluid through the fluid interface in use. Also disclosed is a system, a landing gear controller, a method, and an aircraft.

A method includes detecting at least one position measurement of a separator piston of a pitch trim actuator. The method includes detecting at least one pressure measurement of an oil. The method includes detecting at least one temperature measurement of the oil. The method includes storing at least one position value based on the at least one position measurement of the separator piston, at least one pressure value based on the at least one pressure measurement of the oil and at least one temperature value based on the at least one temperature measurement of the oil. The method includes determining whether the pitch trim actuator requires servicing based on the at least one position value, the at least one pressure value, and the at least one temperature value.

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.