Control system for a concrete block forming machine

Claim 1

A BLOCK FORMING MACHINE HAVING A MOLD OPEN AT ITS TOP AND BOTTOM AND MEANS TO VIBRATE THE MOLD UNTIL BLOCK-FORMING MATERIAL SUPPLIED THERETO REACHES A PREDETERMINED LEVEL, A PALLET BELOW THE MOLD ON WHICH THE BLOCK FORMED FROM THE MATERIAL RESTS, A PALLET SUPPORT FRAME TO POSITION THE PALLET TO CLOSE THE BOTTOM OF THE MOLD, AND A PRESSURE STRIPPER HEAD FRAME HAVING A PRESSURE STRIPPER HEAD MOVABLE DOWNWARDLY AND RELATIVELY TO THE PALLET SUPPORT FRAME TO COMPACT SAID MATERIAL TO THE SAID LEVEL, BLOCK HEIGHT SENSING MEANS ON SAID PRESSURE STRIPPER HEAD FRAME AND SAID MOLD MOVABLE RELATIVE TO EACH OTHER DURING THE COMPACTING OPERATION TO MEASURE THE BLOCK HEIGHT FROM THE TOP OF THE PALLET, FIRST PUSH ROD MEANS ON SAID SUPPORT FRAME, SECOND PUSH ROD MEANS ON THE PRESSURE STRIPPER HEAD FRAME VERTICALLY DISPOSED AND PROJECTING TOWARD EACH OTHER, ONE OF SAID ROD MEANS BEING MOUNTED ON ITS ASSOCIATED FRAME FOR SLIDING MOVEMENT RELATIVELY TO THE OTHER ROD MEANS, AND COUPLING MEANS ON THE MACHINE NORMALLY PERMITTING SAID RELATIVE SLIDING MOVEMENT OF THE SAID ROD MEANS AND CAPABLE OF COUPLING SAID ROD MEANS TO PREVENT SAID RELATIVE SLIDING MOVEMENT, SAID COUPLING MEANS COMPRISING A FLUID-ACTUATED CYLINDER AND PISTON UNIT MOUNTED ON SAID FRAME COAXIAL WITH SAID SLIDING ROD MEANS, SAID CYLINDER AND PISTON UNIT INCLUDING A PISTON ROD PROJECTING THEREFROM TOWARD AN AXIALLY ALIGNED END OF SAID SLIDABLE ROD MEANS, CONTROL MEANS MOUNTED ON THE MACHINE INCLUDING SAID HEIGHT SENSING MEANS, TIMED TO ACTUATE, UPON SAID LEVEL BEING REACHED, THE CYLINDER AND PISTON UNIT TO COUPLE SAID PUSH ROD MEANS AND ACCORDINGLY SAID PRESSURE STRIPPER HEAD AND PALLET SUPPORT FRAMES AGAINST RELATIVE VERTICAL MOVEMENT AND TO UNITARILY MOVE SUCH COUPLED PRESSURE HEAD AND PALLET FRAME VERTICALLY RELATIVE TO THE MOLD, WHEREBY THE HEIGHT OF THE FORMED BLOCK IS NOT AFFECTED BY THE THICKNESS OF THE PALLET, SAID CONTROL MEANS INCLUDING A CONTROL VALVE FOR ACTUATING SAID CYLINDER AND PISTON UNIT, SAID SLIDABLE ROD MEANS COMPRISING A ROD SLIDABLY MOUNTED IN A BRACKET ON SAID PRESSURE STRIPPER HEAD FRAME, A BUSHING ADJUSTABLY MOUNTED IN THE BRACKET FOR SLIDABLY RECEIVING THE UPPER END OF THE ROD, MEANS FOR SLIDABLY RETAINING THE ROD IN THE BUSHING, SAID CYLINDER AND PISTON UNIT BEING CARRIED BY THE BRACKET WITH ITS PISTON ROD PROJECTING DOWNWARDLY IN COAXIAL ALIGNMENT WITH THE UPPER END OF THE ROD, AND A STOP ON THE ROD FOR ENGAGING THE LOWER END OF SAID BUSHING.