Abstract Apparatus for forming a concrete block having the usual block with two cavities connected to a small facing block or slab by web portions spaced from the top and bottom of the block and slab, comprises the usual mold box with cores for the block cavities and spaces between the block and slab. Core portions are provided on the stripper head for filling the spaces between the top of the webs and the top of the block. Core portions are provided for filling the spaces between the bottoms of the webs and the bottom of the block, the core portions being slideable from withdrawn position in cavity core recesses to extended position underlying the web spaces. Motor means are provided on the outer side of the mold box sides for extending and retracting the slideable core portions.
A mold box for forming concrete blocks having undercut portions comprising side members forming a four sided frame open at top and bottom, void-forming core members supported by the side members within the frame, at least one void-forming core member having a recess therein, at least one undercutting core member movable in the box, and motor means secured to the frame side for moving the undercutting core member into undercutting position and for withdrawing the undercutting core member into the core recess.
Claim 2
Dependent Claim
82 words
A mold box for forming concrete blocks having undercut portions comprising side members forming a four sided frame open at top and bottom, void-forming core members supported by the side members within the frame, at least one void-forming core member having a recess therein, at least one undercutting core member movable in the box, and motor means secured to the frame side for moving the undercutting core member into undercutting position and for withdrawing the undercutting core member into the core recess.