Seal manufacture and assembly

Claim 1

An elongated laterally expansible moulded elastomeric seal for use in expanded sealing relation between a first machine part and a second machine part to be maintained in fluid sealing relation with said first part, said seal having an elongated body, an external shoulder portion thereof for attachment of the seal to a said machine part, an elongated fissure within said seal body extending substantially the full length thereof having a filler piece therein made of material non-adherent to said seal, the filler piece having a cross-section form devoid of external cutting edges and serving to substantially fill the fissure when the seal is in an uninflated condition, the filler piece having an elongated fluid flow path recessed therein to provide a flow passage between opposed faces of the filler piece, the recess being located in aligned flow conducting relation with passage means providing inflation and deflation of the seal, said filler piece precluding blockage of said passage means by an opposing wall portion of the fissure when in a pressurized condition, whereby the seal may be substantially completely deflated.