Patent ID: 7131820

Claim:
A process for controlling a thick matter pump, including two conveyor cylinders ( 10 ) communicating via openings ( 12 ) with a material reservoir ( 14 ) and with conveyor pistons ( 26 ) operated in counterstroke, as well as a pipe branch ( 18 ) provided within the material reservoir ( 14 ) connected on the inlet side alternative with one of the openings ( 12 ) of the conveyor cylinders with freeing of the respective other opening and on the outlet side connected with a conveyance conduit ( 20 ), in which thick matter is suctioned in during pump operation through the conveyor cylinder ( 10 ) which is open at the time towards the material reservoir ( 14 ) and is conveyed through the other conveyor cylinder ( 10 ) which is connected to the branch pipe ( 18 ) and through the conveyance conduit ( 20 ) with building up of a thick matter column towards the outlet thereof, wherein during a pausing of pumping the thick matter column in the conveyance conduit ( 20 ) and/or the branch pipe ( 18 ) and/or the conveyor cylinders ( 10 ) is at least temporarily maintained in motion by operating the conveyor piston ( 26 ) and/or the branch pipe ( 18 ) for producing an alternating back and forth movement of the thick matter column, without thick matter exiting from the outlet side of the conduit ( 20 ), wherein at the onset of pausing of pumping, starting with a temporarily resting condition, first thick matter is suctioned out of the conveyance conduit ( 20 ) by a backwards stroke of the piston ( 26 ) of the conveyor cylinder ( 10 ) connected at this time with the branch pipe ( 18 ), that subsequent to the first backwards stroke the branch pipe ( 18 ) is switched over to the other conveyor cylinder ( 10 ) and thick matter is suctioned out of the conveyance conduit ( 20 ) by a backwards stroke of its piston ( 26 ) and that subsequent to the last backwards stroke the branch pipe ( 18 ) is switched over to the respective other conveyor cylinder ( 10 ) and tick matter is pressed into the conveyance conduit ( 10 ) by a forwards stroke of its piston, without matter exiting from the outlet side of the conveyance conduit.