摘要 |
System and method for dispensing liquids into concrete mixer drums, particularly suitable for use on concrete mix trucks, involve use of liquid admixtures nozzle that is separate from water conduit and water nozzle, the admixtures nozzle being aimed and focused to spray through drum opening with dispersion pattern substantially within air/concrete interface defined by minimal volume concrete contained within the drum; and the water conduit or nozzle having a dispersion pattern preferably whereby wash water hits a portion of the inner drum wall and a portion of the air/concrete interface defined by a maximum amount of concrete contained within the drum. In preferred embodiments, a check valve assembly is used to connect separate admixture and water lines, so that both admixture and water nozzles can be used simultaneously during purging operation. |