| 摘要 |
An apparatus, and related method, for laying sand and/or a sand reinforcement matrix onto a pre-prepared surface, includes an apparatus having a hopper for providing a matrix to be laid, a plunger at the forward end, in the sense of direction of movement of the apparatus, of the hopper and an element for reciprocating the plunger for taking material from the hopper and delivering it through an extrusion aperture in the rear thereof to an extrusion mold. The extrusion is effected by moving forwardly as pressure is applied to the matrix to be extruded and as the mold passes over the matrix. The extrusion of a sand, or a sand reinforcement, is compacted in the extrusion by using the weight of the apparatus against which the extrusion plunger acts together with the impaction of previously extruded material. The plunger moves forwardly so that material in the hopper can fall in front of the plunger; the plunger is moved rearwardly causing this material to move into the extrusion mold until compaction commences to take place, at which time compaction is increased until the pressure on the plunger is sufficient to physically cause the apparatus to move.
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