Sealing membrane for gas in accumulator - consists of inner and outer layers of elastomer bonded together round edges, leaving intermediate space at least half filled with oil

摘要

Gas-tight membrane e.g. to seal a gas over oil in an hydraulic accumulator, has inner and outer layers which are bonded together in places to form a liquid-tight space between them and this space is at least half filled with a liq. The membrane has the outer layer (2), the inner liner (3) and the intermediate space (4) filled with e.g. an oil. As an hydraulic accumulator it seals off the gas chamber (7) from the oil-filled chamber (8) and it is held in position by the clamping ring (9) which fits between two ribs (10,11). The membrane is produced by a type of two-stage injection moulding process (resembling tennis ball prodn.) in which the outer and inner layers are moulded and cured and also bonded together at the edges, so leaving an internal space. After curing and deflashing, the oil filling is injected through a suitable needle. ADVANTAGE - The prod. uses a liq. as a seal and this liquid can follow every elastic shape taken up by the membrane and hence maintains its gas-tightness.