A piston accumulator has an accumulator housing and a separating piston (8) guided for longitudinal motion in the accumulator housing. The separating piston separates a liquid side (4) from a gas side (10) in the accumulator housing. Liquid unintentionally transitions from the liquid side (4) to the gas side (10) despite a piston seal on the separating piston (8). By a return device (28), the transitioned liquid is at least partially returned from the gas side (10) of the accumulator housing to the liquid side (4) of the accumulator housing.

A piston accumulator has an accumulator housing and a separating piston (8) guided for longitudinal motion in the accumulator housing. The separating piston separates a liquid side (4) from a gas side (10) in the accumulator housing. Liquid unintentionally transitions from the liquid side (4) to the gas side (10) despite a piston seal on the separating piston (8). By a return device (28), the transitioned liquid is at least partially returned from the gas side (10) of the accumulator housing to the liquid side (4) of the accumulator housing.

A hydraulic accumulator, in particular in the form of a piston accumulator, has an accumulator housing (10) and a separating element (20) arranged in the housing. The separating element is in the form of a piston, which separates a fluid side (22) from a gas side (24). At least the gas side (24) can be inspected, at least in part, by at least one sight glass (34, 36) that is fixed in the accumulator housing (10).

This invention relates to hydraulic energy storage and management systems. In particular, this invention relates to a hydraulic energy management system that has a reconfigurable energy storage and release capability that adjusts to varying available energy input and power demand output requirements. The hydraulic energy management system can be resized by a hydraulic bridge circuit to permit hydraulic power units to be added or removed, both physically and operationally, to capture available energy over time, adjust to peak demand cycles, and maintain power output in the event of a failure of a portion of the system.

A pressure accumulator includes an accumulator housing having first and second ports for receiving first and second pressure mediums, respectively, a movable separating element subdividing an interior of the accumulator housing into at least first and second working spaces, the first working space accommodating the first pressure medium and the second working space accommodating the second pressure medium, wherein the first port is in fluid communication with the first working space and the second port in fluid communication with the second working space. At least one sensor is operatively coupled to the first working space for measuring at least one characteristic of the first working space, and a gas generator is operative to generate a gas from ambient air, the gas generator including an outlet for outputting the generated gas, the outlet in fluid communication with the first port. A controller is operatively coupled to the at least one sensor and the gas generator, the controller configured to calculate an amount of gas in the first working space based on the at least one characteristic and upon the calculated amount of gas in the first working space being below a first threshold level, generate a command to introduce gas from the gas generator into the first working space.

An active accumulator system which automatically adjusts or adapts the charge pressure or volume of an accumulator to maintain an optimal charge pressure or volume of the accumulator may provide optimal operation of a pump. An active accumulator system may comprise a flow line coupled to a pump, wherein a fluid flows through the flow line to the pump, an accumulator coupled to the flow line, a transducer coupled to the pump, wherein the transducer detects a parameter of the pump at an inlet of the pump, and a controller coupled to the transducer and the accumulator, wherein the controller receives the parameter, and wherein the controller regulates air flow to the accumulator such that the accumulator is adjusted to an optimal charge pressure based at least in part on the parameter.

An active accumulator system which automatically adjusts or adapts the charge pressure or volume of an accumulator to maintain an optimal charge pressure or volume of the accumulator may provide optimal operation of a pump. An active accumulator system may comprise a flow line coupled to a pump, wherein a fluid flows through the flow line to the pump, an accumulator coupled to the flow line, a transducer coupled to the pump, wherein the transducer detects a parameter of the pump at an inlet of the pump, and a controller coupled to the transducer and the accumulator, wherein the controller receives the parameter, and wherein the controller regulates air flow to the accumulator such that the accumulator is adjusted to an optimal charge pressure based at least in part on the parameter.

A hydraulic pumping system can include a hydraulic actuator with a magnet that displaces with a piston, and a sensor that continuously detects a position of the magnet. A ferromagnetic wall of the hydraulic actuator is positioned between the magnet and the sensor. A hydraulic pumping method can include incrementally lowering a lower stroke extent of a rod string reciprocation over multiple reciprocation cycles of the rod string, and automatically varying the lower stroke extent or an upper stroke extent of the rod string reciprocation, in response to a measured vibration. Another hydraulic pumping method can include solving a wave equation in the rod string, and automatically varying a reciprocation speed of the rod string in response to a change in work performed during reciprocation cycles of the hydraulic actuator or a change in detected force versus displacement in different reciprocation cycles of the hydraulic actuator.

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 method is provided for determining a gas charge pressure P.sub.calcGC of a hydraulic accumulator within a hydraulic fluid system. The method includes receiving pressure decay data representing the pressure decay within a self-pressurizing hydraulic reservoir of the hydraulic fluid system as the self-pressurizing hydraulic reservoir depressurizes from an operating pressure of the self-pressurizing hydraulic reservoir towards atmospheric pressure. The method also includes calculating the gas charge pressure P.sub.calcGC of the hydraulic accumulator using the received pressure decay data of the self-pressurizing hydraulic reservoir.