VALVE UNIT FOR USE IN CONCRETE PUMPS

摘要

A fluid passage change over valve unit for use in concrete pumps wherein a passage change over valve member located within a hopper is connected at its outlet port to a delivery line for pivoting about the latter so that an inlet port thereof is swung to alternately communicate with a pair of piston pumps having pump openings into the hopper. The valve unit is provided with a pair of guide members disposed along both sides of the valve member. One end of each guide member opens upwards and the other end is disposed to come into alignment with the opening of corresponding one of the piston pumps for guiding a fluid concrete within the hopper to the one pump when the valve member communicates with the other pump.