A method of charging a hydro-pneumatic energy storage system is described. The system has a first hydro-pneumatic accumulator with a first hollow vessel. Disposed within the first hollow vessel is a first compressible volume containing a first amount of gas. The system has a second hydro-pneumatic accumulator with a second hollow vessel. Disposed within the second hollow vessel is a second compressible volume containing a second amount of gas. The gas contained in the first volume is pre-pressurized to a first hydrostatic pre-charge pressure and the gas contained in the second volume is pre-pressurized to a second hydrostatic pre-charge pressure. The second pre-charge pressure is higher than the first pre-charge pressure. In addition, the gas in the first volume is pressurized by discharging a non-compressible hydraulic fluid into the first vessel while keeping a quantity of non-compressible hydraulic fluid contained in the second vessel constant to keep the pressure of the gas contained in the second volume at the second pre-charge pressure.

A hoop wrapped composite pressure vessel (1A) is provided in which a dome portion of a vessel main body (1) has a greater thickness than a thickness of a circularly cylindrical portion (2) and has a shape in which an outer circumferential curved surface initiating point (30A) that is situated axially outwards of an external diametrical surface (20) of the vessel main body that is flat in an axial direction is offset further axially outwards than an internal circumferential curved surface initiating point (31A) that is situated axially outwards of an internal diametrical surface (21) of the vessel main body that is flat in the axial direction and in which an FRP (10) is wound like a hoop around the vessel main body properly.

The invention relates to a method for producing pressure vessels, including pressure accumulators, such as hydraulic accumulators and parts thereof (24), characterized in that they are at least partially produced by means of a 3D printing method.

The invention relates to a method for producing wall parts (24) of a housing for pressure vessels by means of a 3-D printing method, wherein material is applied layer-by-layer in order to form each wall part (24). Said method is characterized in that, in case of wall part geometries (28) that lead to distortions (44) that impede the application of material, the layer thickness in the application of material must be selected in such a way that the particular distortion (44) is avoided and that the formation of wall part geometries (28) that are critical in this respect is performed without support parts.

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.

A drop-in signal accumulator piston assembly replaces an original equipment (OE) signal accumulator piston in a vehicle transmission hydraulic circuit. The OE signal accumulator piston is positioned in a bore in a valve body that has an open end and a fluid port. The drop-in signal accumulator piston assembly includes a cylindrical sleeve having open first and second ends, one of the first and second ends defining a reduced diameter region, and a piston positioned in the sleeve. A spring is positioned in part in the piston and in part extending beyond and end of the piston. The sleeve is positioned in the valve body bore, with the piston, and the spring. A method for replacing an original equipment (OE) signal accumulator piston in a transmission hydraulic circuit is also disclosed.

An expansion tank includes two half-shells coupled to each other, an inner flexible membrane suited to divide the inside of the casing in two compartments, a counter cap made of a thermoplastic material, a pipe fitting suited to provide a connection and having a first tubular portion and a second portion in the shape of a flat ring that are made of a thermoplastic material, wherein the second ring-shaped portion is joined to the counter cap at the level of an opening in the tank.

A medical fluid delivery machine including: a medical fluid pump including a pneumatically actuated pump chamber and first and second pneumatically actuated medical fluid valve chambers located respectively upstream and downstream of the pneumatically actuated pump chamber; a compressor for creating positive pressure air; and an accumulator storing the positive pressure air for delivery to at least one of the pneumatically actuated pump chamber, the first pneumatically actuated medical fluid valve chamber, or the second pneumatically actuated medical fluid valve chamber, the accumulator holding an elastic bladder that inflates under positive pressure air from the compressor, creating additional positive pressure that increases the amount of positive pressure air that the accumulator can provide.

The present invention is a distributed piston elastomeric accumulator which stores energy when its elastomeric member stretches from its original length in response to the flow of a pressurized fluid. The stored energy is returned when the fluid flow is reversed and the accumulator discharges the fluid as its elastomeric member returns to its original length and moves the piston to its initial position. At least one part of the novelty of the invention is that the accumulator is not subject to radial strain gradients and the accumulator allows for precise pressure and linear position measurements. Accordingly, the invention allows for optimization of the energy strain storage capacity of a given elastomer.

A drop-in signal accumulator piston assembly to replace an original equipment (OE) signal accumulator piston in a vehicle transmission hydraulic circuit, the OE signal accumulator piston positioned in a bore in a valve body having a fluid port. A cylindrical sleeve has open first and second ends with an internal diameter that reduces at a transition therebetween. A piston is positioned in the sleeve and has open and closed ends. The cylindrical sleeve is configured such that the transition in the internal diameter limits movement of the piston within the cylindrical sleeve. A spring is positioned in part in the open end of the piston and in part extending beyond an end of the piston. The sleeve is positioned in the valve body bore, with the piston and the spring positioned in the sleeve. The sleeve, the piston, and the spring are enclosed within the valve body bore.