摘要 |
The invention discloses an elastic lid made of plastic material particularly suited for accumulators for electric traction. The elasticity of the lid is given, not only by the material which is copolymer polypropylene or polyethylene, but also by the hollow shape obtained on the entire surface; the hollowness is turned upwards abd it allows the extension of the poles during the aging process of the accumulator, while preventing the lid from breaking or from detaching itself from the casing. The invention foresees also a moulded circular ring having a tapered section around the refilling opening, it being elastic too, which prevents the spreading of electrolyte drops during the refilling operation and which also acts as a gasket for the cap. According to one form of execution, the ring (5) has a tapered section having its taper turned upwards. A variation is foreseen in which the ring (8) has the taper turned downwards and some steps which make the material lighter in weight. |