Process for producing a structural concrete block

Claim 1

A process for producing a structural concrete block having on one surface in combination an irregular cut pattern portion simulant of a cut surface of portion of a natural rock formation which comprises the steps of feeding said blank to a predetermined position by an intermittently driven conveyor, said blank having on one surface alternate grooves and projections, stopping the movement of said conveyor when the blank is positioned in said predetermined position, extending a transfer mechanism so as to transfer the blank onto a guide member, upon the transfer of said blank onto said guide member, retracting said transfer mechanism, driving said conveyor so as to feed a second similar blank to said predetermined position, stopping the movement of the conveyor when the second blank is positioned in the predetermined position, extending said transfer mechanism so as to transfer said second blank onto said guide member thereby to push said first-mentioned blank onto a cutting blade member in a cutting station, said cutting blade member having on one surface a plurality of teeth of the same pitch as the grooves on said blank for engaging the grooves, engaging the teeth of the cutting member with the grooves of the blank, actuating a blank holding down mechanism so as to hold said first-mentioned blank on said blade member against movement relative to the latter and moving said blade member relative to the blank so as to shear said projections on the blank.