Method and means for molding an aqueous fibrous mixture

Claim 2

A PROCESS FOR MOULDING HOLLOW ARTICLES FROM AN EASILY FLOWABLE MIXTURE OF WATER, FIBRES AND HYDRAULIC BINDER COMPRISING (A) INJECTING THE MIXTURE INTO A MOULD CAVITY DEFINED BETWEEN A RIGID WALL SURFACE WHICH IS AT LEAST PARTLY WATER-PERVIOUS AND RESILIENTLY YIELDABLE WALL SURFACE, (B) CLOSING SAID MOULD CAVITY AND SIMULTANEOUSLY DISPLACING A PORTION OF SAID RIGID WALL SURFACE INTO SAID MOULD CAVITY WHILE RIGIDLY BACKING UP THE RESILIENTLY YIELDABLE WALL SURFACE SO AS TO REDUCE THE VOLUME OF THE MOULD CAVITY SUBSTANTIALLY TO THAT OF THE DESIRED HOLLOW ARTICLE, THEREBY EXPRESSING A SUBSTANTIAL PORTION OF THE WATER FROM SAID MIXTURE IN THE MOULD CAVITY, AND (C) APPLYING FLUID UNDER PRESSURE TO SAID RESILIENTLY YIELDABLE WALL SURFACE TO URGE THE LATTER TOWARD SAID RIGID WALL SURFACE, THEREBY COMPLETING THE EXPRESSING OF WATER FROM THE MIXTURE AND THE COMPRESSION OF THE LATTER IN SAID MOULD CAVITY.

Claim 3

APPARATUS FOR MOULDING HOLLOW ARTICLES FROM AN EASILY FLOWABLE MIXTURE OF WATER, FIBRES AND HYDRAULIC BINDER, SAID APPARATUS COMPRISING (A) A RIGID, AT LEAST PARTIALLY WATER-PERVIOUS WALL STRUCTURE, A RESILIENTLY YIELDABLE WALL STRUCTURE SPACED FROM SAID RIGID WALL STRUCTURE TO DEFINE A MOULD CAVITY THEREBETWEEN AND A RIGID SUPPORT STRUCTURE ENGAGEABLE WITH SUBSTANTIALLY THE ENTIRE SURFACE OF SAID RESILIENTLY YIELDABLE WALL STRUCTURE FACING AWAY FROM SAID RIGID WALL STRUCTURE, (A) MEANS DEFINING AN OPENING FOR THE INJECTION INTO SAID MOULD CAVITY OF THE EASILY FLOWABLE MIXTURE, (B) SAID RIGID WALL STRUCTURE HAVING A MOVABLE PORTION DISPLACEABLE INTO SAID MOULD CAVITY FOR REDUCING THE VOLUME THEREOF AFTER THE INJECTION OF THE MIXTURE INTO SAID MOULD CAVITY, THEREBY EXPRESSING A SUBSTANTIAL PORTION OF THE WATER FROM THE MIXTURE WHILE THE SHAPE OF SAID RESILIENTLY YIELDABLE WALL STRUCTURE IS POSITIVELY DETERMINED BY SAID RIGID SUPPORT STRUCTURE; AND (B) MEANS FOR APPLYING FLUID UNDER PRESSURE BETWEEN SAID RIGID SUPPORT STRUCTURE AND SAID RESILIENTLY YIELDABLE WALL STRUCTURE TO URGE THE LATTER TOWARD SAID RIGID WALL STRUCTURE, THEREBY COMPLETING THE EXPRESSING OF WATER FROM THE MIXTURE AND THE UNIFORM COMPRESSION OF THE LATTER IN SAID MOULD CAVITY.

Claim 4

APPARATUS FOR MOULDING HOLLOW ARTICLES FROM AN EASILY FLOWABLE MIXTURE OF WATER, FIBRES AND HYDRAULIC BINDER, SAID APPARATUS COMPRISING (A) A RIGID, AT LEAST PARTIALLY WATER-PERVIOUS WALL STRUCTURE, A RESILIENTLY YIELDABLE WALL STRUCTURE SPACED FROM SAID RIGID WALL STRUCTURE TO DEFINE A MOULD CAVITY THEREBETWEEN AND A RIGID SUPPORT STRUCTURE ENGAGEABLE WITH SUBSTANTIALLY THE ENTIRE SURFACE OF SAID RESILIENTLY YIELDABLE WALL STRUCTURE FACING AWAY FROM SAID RIGID WALL STRUCTURE, (A) MEANS DEFINING AN OPENING FOR THE INJECTION INTO SAID MOULD CAVITY OF THE EASILY FLOWABLE MIXTURE, (B) SAID RIGID WALL STRUCTURE HAVING A MOVABLE PORTION DISPLACEABLE INTO SAID MOULD CAVITY FOR REDUCING THE VOLUME THEREOF AFTER THE INJECTION OF THE MIXTURE INTO SAID MOULD CAVITY, THEREBY EXPRESSING A SUBSTANTIAL PORTION OF THE WATER FROM THE MIXTURE WHILE THE SHAPE OF SAID RESILIENTLY YIELDABLE WALL STRUCTURE IS POSITIVELY DETERMINED BY SAID RIGID SUPPORT STRUCTURE; AND (B) MEANS FOR APPLYING FLUID UNDER PRESSURE BETWEEN SAID RIGID SUPPORT STRUCTURE AND SAID RESILIENTLY YIELDABLE WALL STRUCTURE TO URGE THE LATTER TOWARD SAID RIGID WALL STRUCTURE, THEREBY COMPLETING THE EXPRESSING OF WATER FROM THE MIXTURE AND THE UNIFORM COMPRESSION OF THE LATTER IN SAID MOULD CAVITY.