The present invention provides lightweight high-pressure accumulators that avoids diaphragm failure observed in conventional diaphragm accumulators. Lightweight high-pressure composite overwrapped accumulators of the invention are made from a plurality of hollow casings that are mated to form an accumulator housing. The accumulator housing is overwrapped with a composite material to provide additional mechanical strength and structural integrity. More significantly, the accumulators of the invention includes a plurality of annular grooves and a plurality of bulb on the flexible diaphragm such that the plurality of bulbs on the flexible diaphragm are placed in the plurality of annular grooves that are formed between the first and the second hollow casing. In this manner, diaphragm failure is significantly reduced or even completely eliminated during repeated high pressure charge/discharge cycle of the accumulator.

A fluid tank includes polymeric liner comprising an upper wall and a lower wall. The upper wall and the lower wall define a cavity therebetween. A weld joint joins the upper and lower walls together. A method for assembling a fluid tank includes overlapping surfaces of an upper wall and a lower wall to form a liner defining a cavity. The method includes joining the surface of the upper wall and the surface of the lower wall together by welding to form a weld joint between the upper wall and the lower wall. The method can include cooling the weld joint to control warpage of the liner at the weld joint.

An electrohydraulic system for use under water includes an electrohydraulic actuator and a container having an internal space provided for forming a volume which is enclosed from the environment and which is provided for receiving a hydraulic pressurized fluid. A hydraulic cylinder is provided in the internal space of the container, the inside of which is divided into a first cylinder chamber and a second cylinder chamber by a piston to which a first piston rod and a second piston rod are connected. The two active surfaces of the piston are the same or approximately the same size.

A method for the production of a bladder accumulator (10) that separates two media chambers (16, 18) from one another in a storage housing (12) by a bladder body (14). The following production steps include extruding a plastic tube over the bladder body (14), shaping the plastic tube with the integrated bladder body (14) in a molding tool that corresponds to a predeterminable plastic core container (20), and winding at least one plastic fiber from the outside on the plastic core container (20) for the purpose of creating the storage housing (12).

A system for determining the location of a movable element within a container is provided in which a linear variable differential transformer (LVDT) is formed with the container and the movable element therein. The LVDT includes a coil assembly including a primary or excitation winding, a secondary or output winding, and a movable element or core that is magnetically permeable. Measurement of an output signals allows for precise determination of the movable element location relative to the container. The system can be utilized to determine fluid volumes in accumulators used for controlling subsea equipment by monitoring the location of a movable element, e.g., a piston, within a hydraulic fluid accumulator.

An accumulator assembly includes a first cylindrical casing, a second cylindrical casing co-axially positioned within the first cylindrical casing, wherein a cylindrical space is formed between the first cylindrical casing and the second cylindrical casing, the space defining a gas volume, first and second end caps attached to and closing the distal ends of the first and second cylindrical casings, each end cap having four radially outwardly extending sides defining reinforcement support flanges, wherein each reinforcement support flange includes a reinforcing element engagement surface, and a reinforcing element extending around each of two opposing support flanges, such that the reinforcing element engagement surfaces define a pathway for the reinforcing elements, wherein the reinforcing elements retain the first and second end caps to axial ends of the inner and outer casings.

A two-stage accumulator based pneumatic supply architecture (TAPSA) is provided for rapid actuation of multiple compliant pneumatic actuators simultaneously for their potential applications in wearable robotic assistive and rehabilitative devices, serving as light-weight and untethered actuation systems. The TAPSA comprises Polyethylene Terephthalate (PET) bottles serving as primary accumulators and secondary accumulators connected in series. Individual targeted levels of pneumatic pressures are achieved in actuators of the TAPSA within targeted durations of time for the rapid actuation of the actuators by the action of Pulse Width Modulation (PWM) controlled solenoid valves supplying pressurized air from the secondary accumulators which are in turn pressurized in prior to predetermined levels based on system performance model developed by a data driven approach utilized in the TAPSA. Rejuvenation of pressure in the secondary accumulators occurs through a pressure feedback based PD control scheme executed in between consecutive actuation cycles.

The invention relates to a method for the production of a bladder accumulator (10) which separates two media chambers (16, 18) from one another in a storage housing (12) by means of a bladder body (14), comprising at least the following production steps:extruding a plastic tube over the bladder body (14);shaping the plastic tube with the integrated bladder body (14) in a molding tool that corresponds to a predeterminable plastic core container (20), andwinding at least one plastic fiber from the outside on the plastic core container (20) for the purpose of creating the storage housing (12).

The mechanism in the invention provides a solution for automated, remote regulating high pressure air in the industrial air tube system. With double layer electromagnetic valves, the mechanism assure the comfortable and safe working platform for humans and equipment. The mechanism comprises: mechanical valve, 20 L pneumatic tank, pressure gauge, sealed metal box, static disc, electromagnetic relay with movable stem, capacitor, low pressure air tube, high pressure air tube, electrical wire, electromagnetic relay.

A fluid tank includes polymeric liner comprising an upper wall and a lower wall. The upper wall and the lower wall define a cavity therebetween. A weld joint joins the upper and lower walls together. A method for assembling a fluid tank includes overlapping surfaces of an upper wall and a lower wall to form a liner defining a cavity. The method includes joining the surface of the upper wall and the surface of the lower wall together by welding to form a weld joint between the upper wall and the lower wall. The method can include cooling the weld joint to control warpage of the liner at the weld joint.