Bulk material pump, particularly hydraulically operated concrete pump incorporated in delivery vehicle, has oil pump releasing variable pressure volumes through first/second apertures and drive cylinders in flow connection with oil pump

摘要

The hydraulically operated pump device for bulk material, particularly a concrete pump incorporated in a delivery vehicle, involves an oil pump (100) releasing variable pressure volumes through first or second apertures (100a,100b). First and second hydraulic drive cylinders (120,140) are in flow connection with the oil pump. The first drive cylinder comprises a cylinder housing (160) with an axial bore (180) and a drive piston (200) with a connecting rod (220), moving in the cylinder housing, dividing the axial bore into a basic chamber (240) and a head chamber (260). The volumes of the basic and head chambers alter with the position of the piston, so that when the volume of the basic chamber is greater, that of the head chamber is proportionally smaller, and vice versa. The basic chambers of the first and second drive cylinders are connected via fluid conduits with the oil pump. The head chambers of the two cylinders are in flow connection.