Abstract:
A vertically oriented air-tight bellows has its lower end connected to an opening in the top of the reservoir by an air-tight connection. A cover closes the upper end of the bellows and has secured thereto a fill inlet in communication with the interior of the bellows and carrying a removable cap. Vertical guide means guide the bellows in substantially vertical movement. Advantageously the bellows have means for lifting upwardly the upper end of the bellows and means for holding the bellows in an upwardly expanded position for filling. Preferably the cap for the fill inlet is transparent to permit viewing the hydraulic fluid in the bellows. A preferred embodiment has means to sight the position of the top of the bellows and a manually actuated bleed valve to vent gas from the interior of the bellows. A housing for the bellows is provided for situations where exposure to dirt particles is substantial. The capacity of an individual bellows may be varied widely and, if desired, overall capacity may be increased by employing a plurality of bellows.
Abstract:
The invention relates to a method and apparatus for charging a hydro-pneumatic reservoir with gas under pressure. The reservoir is positioned between two vertically aligned supporting members, with the oil charging port and gas charging port of the reservoir axially aligned. The supporting member on which the oil charging port is positioned, is vertically adjustable. The gas charging port carries an initially loose fitting bushing with an expander member at its outer end, the bushing permitting flow of gas therearound to permit charging of the reservoir. A force applying member is slidably mounted in the uppermost supporting member such that when gas under pressure is applied, it will cause the force applying member to move upwardly and the gas under pressure will pass around the bushing into the reservoir to charge the latter. After the reservoir is charged, oil under pressure is applied to the force applying member to move the latter downwardly to react against the expander member, forcing the latter into the bushing to expand the latter and seal the gas port of the reservoir.
Abstract:
A flexible diaphragm for a hydraulic fluid accumulator is provided with a plurality of concentric circular ridges for engagement with the wall surface of the accumulator housing between concentric circular rows of fluid discharge openings formed in the housing. The ridges maintain the diaphragm in spaced relation to the discharge openings to prevent extrusion of the diaphragm into the discharge openings.
Abstract:
This invention relates to a hydropneumatic accumulator comprising a piston and cylinder arrangement defining in the cylinder a first compartment in which is provided a gas which is under pressure and which has a density less than that of nitrogen and a second compartment in which liquid is provided. Helium is the gas preferably used, such that, on the one hand, a much larger volume of the liquid can be stored in the accumulator at a predetermined pressure than is possible using nitrogen, and, on the other hand, the variations in pressure due to variations in temperature is much less than with nitrogen. The invention is particularly applicable to hydraulic controls for electric circuit breakers.
Abstract:
An autoclave tank, for hydraulic lifting plants, of the kind including a rigid external envelope inside which is contained an internal elastic envelope for holding water, is characterised by means inside the tank for limiting the maximum volume of expansion of the internal elastic envelope, said means consisting of a tubular wall extending through the entire length of the external envelope of the tank, and fixed thereto at the base and at the summit.
Abstract:
The present invention relates to a pressure reservoir comprising a rigid envelope having two ports, a flexible separator in the form of a bladder disposed in the interior of the said envelope and dividing it into two compartments for fluids which are respectively in communication with said ports, the bladder being adapted to move to the vicinity of one of the said ports, which is equipped with a strainer device or screen against which the bladder abuts in operation.