Abstract:
A hydraulic servo-control of a servo-controlled gearbox comprises hydraulic actuators defining chambers, a storing tank containing control fluid used by the actuators at room pressure, a hydraulic accumulator containing control fluid under pressure, a motor pump drawing the fluid from the tank and feeding it under pressure to the accumulator and solenoid valves selectively connecting the chambers to the tank and accumulator. The accumulator includes an outer housing, a piston arranged and axially slidable and mobile inside the housing and defining there a first variable-volume chamber for a gas and second variable-volume chamber for the fluid under pressure, and a limit stopper arranged at an open end of the housing, acting as a striker for the piston, and having an annular circlip and a perforated plate operatively interposed between the circlip and piston.
Abstract:
A hydraulic servo-control of a servo-controlled gearbox provided with a hydraulic accumulator, having an outer housing and a piston that is slidable axially inside the outer housing and adapted to define a first variable-volume chamber for a gaseous material and a second variable-volume chamber for a control fluid under pressure; and at least one limit stop arranged at an open end of the outer housing which serve as a lower limit stop element; wherein the outer housing is provided with an upper limit stop element, which acts to limit the pressure value inside the first variable-volume chamber within a predetermined safety range.
Abstract:
Methods and apparatus to charge accumulators are described. An example system to charge an accumulator apparatus includes a piston disposed within a housing to define a first chamber adjacent a first side of the piston and a second chamber adjacent a second side of the piston. A fill probe having a body and a passageway between a first end of the fill probe and a second end of the fill probe removably couples to the piston to fluidly couple to the passageway of the fill probe to the second chamber of the housing when the accumulator is in a charging condition. A valve is fluidly coupled to the piston to enable fluid flow to the second chamber of the housing via the piston when the fill probe is coupled to the piston.
Abstract:
Methods and apparatus to charge accumulators are described. An example system to charge an accumulator apparatus includes a piston disposed within a housing to define a first chamber adjacent a first side of the piston and a second chamber adjacent a second side of the piston. A fill probe having a body and a passageway between a first end of the fill probe and a second end of the fill probe removably couples to the piston to fluidly couple to the passageway of the fill probe to the second chamber of the housing when the accumulator is in a charging condition. A valve is fluidly coupled to the piston to enable fluid flow to the second chamber of the housing via the piston when the fill probe is coupled to the piston.
Abstract:
A hydroaccumulator, especially a membrane accumulator, has an accumulator housing with two housing parts and a separating element in the housing. The separating element can be a separating membrane dividing the accumulator housing into a gas chamber and a fluid chamber. The gas chamber is connected to carry gas to and from gas refiller through a connection. The gas refiller is formed from an additional housing part connected to the accumulator housing to form a unit. The connection is at least one connecting opening in the accumulator housing connecting the interior of the additional housing part to the gas chamber. Additional gas accumulator volume is provided without otherwise conventional pipework to save money and installation space and avoid conventional leaks which occur in the area of the pipework.
Abstract:
The invention relates to a pressure accumulator which comprises a housing for accommodating fluid, a fluid connection for a fluid flowing into and out of the housing, as well as a spring arrangement against whose force a fluid flowing through the fluid connection is acting, characterised in that at least one part of the spring arrangement is formed by at least one part of the wall of the housing.
Abstract:
In an accumulator in which a peripheral edge of a bladder dividing the interior of a shell into a gas chamber and a liquid chamber is attached to the shell, the radius of curvature of an inner wall of the shell defining the gas chamber is larger than that of an inner wall of the shell defining the liquid chamber. This construction ensures that the diameter of the bladder can be relatively increased, the deflection of the bladder with a variation in pressure in the gas chamber and in the liquid chamber can be increased, and the radius of curvature of a curved portion of the peripheral edge of the bladder can be increased, there by contributing to an overall improvement in the durability of the bladder.
Abstract:
An expandable float assembly is insertable through the lower valve bore in an accumulator or a hole in a tank. The assembly includes a sleeve member and a plurality of floatable arm members. The floatable arm members may be folded to a position substantially parallel to the sleeve members for insertion of the expandable float assembly into the accumulator or tank. After insertion of the expandable float assembly into the accumulator or tank the floatable arm members are deployed to a position substantially perpendicular to the sleeve member.
Abstract:
An elastomeric bladder for dividing a pressure vessel into two chambers is formed in one piece and carries integrally at least one rigid element (18 or 19). A tubular blank bladder 10A of raw elastomer is shaped in a mould by fluid pressure applied to the interior of the blank while the rigid elements 18, 19 are clamped against the ends E1, E2 of the bladder valve and a vulcanization is performed whereby the rigid elements 18, 19 are bonded to the bladder.
Abstract:
A method of assembling hydraulic accumulators of the bladder type having a casing formed from two open-mounted shells rigidly fitted together comprising the steps of fitting the bladder on the mouth of the inner shell, sliding the bladder and inner shell into the outer shell until the bladder fits closely against the inner surface of the outer shell, and rigidly connecting the shells in this position.