CONCRETE BLOCK MOLDING MACHINE HAVING CONTINUOUSLY DRIVEN VIBRATING SHAFT MECHANISM WHICH CAN BE PROGRAMMABLY VIBRATED AND METHOD OF PROGRAMMABLY VIBRATING SUCH MACHINES

摘要

CONCRETE BLOCK MOLDING MACHINE HAVING CONTINUOUSLYDRIVEN VIBRATING SHAFT MECHANISM WHICH CAN BE PROGRAMMABLYVIBRATED AND METHOD OF PROGRAMMABLY VIBRATING SUCH MACHINESABSTRACT OF THE DISCLOSUREA cement block molding machine has a vibratible moldbox incorporating at least one molding cavity for a cementmixture which is to be densified in the cavity. A continuouslydriven shaft assembly mounts an eccentric fixed portion and acircumferentially adjustable balancing mass. The shaft assemblyhas a cylinder with a piston therein, connected to the mass toproduce rotary motion of the mass relative to the fixedeccentric portion. A spring of predetermined rate opposesthis. The pressure of the fluid introduced is varied to changethe amplitude of the vibration imparted during each cycle.