| 摘要 |
A spray nozzle of the type adapted to feed a liquid to a material being sprayed therefrom comprises a tubular spray conduit around which is arranged an annular feed port, this feed port being closed in a liquid-tight manner by resilient material openable by liquid pressure and whose degree of opening, and therefore the quantity of liquid fed to the material, rises linearly with increasing liquid pressure. Preferably, the resilient material is provided by a membrane ring (7) which is a flat ring with inwardly-tapering radial ridges (8b) raised thereon, the gaps between the ridges being filled with an elastomeric material, such that a series of resilient segments (9) is created. Under liquid pressure, the segments are compressed equally, giving a nearly completely annular flow of liquid into the material. The nozzle is particularly useful for the spraying of concrete, especially by the dry method.
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