Process and apparatus for demolding and palletizing cast concrete blocks

A method for demolding cast concrete blocks which are cast in a resilient mold supported in a rigid frame, the mold having a top surface and a plurality of cavities each with an opening at the top surface which cavities form and hold cured cast concrete blocks, the mold having two opposing edges extending along opposite sides of the mold, and wherein the demolded blocks are stacked on a collection surface, the method comprising the steps of:

• a) covering the open top of the mold cavities with a rigid support;
• b) inverting the mold, frame and support whereby the mold and cast block are positioned on the rigid support;
• c) providing demolding apparatus including first and second gripping mechanisms spaced above the collection surface for gripping the two opposing mold edges and wherein each gripping mechanism is pivotable about an axis parallel to the mold edges;
• d) positioning the support with the inverted mold in the demolding apparatus;
• e) engaging the two opposing mold edges with the gripping mechanisms;
• and
• f) withdrawing the support from under the inverted mold whereby the mold is suspended from the gripping mechanisms engaging the two opposing edges and wherein the mold sags and stretches to facilitate release of the blocks from the mold whereby such released blocks fall onto the collection surface, and wherein as the mold sags and stretches, the gripping mechanisms pivot to minimize stress in the mold and wherein the two opposing mold edges are each provided with a raised portion extending along the adjacent edge to extend above the top surface of the mold, and wherein the step of engaging the two opposing mold edges with the gripping mechanism comprises clamping the first mold edge and rib along its length between first clamp members of a first clamping mechanism and clamping the second mold edge and rib along its length between second clamp members of a second clamping mechanism.