Method and device for proportioning and mixing multicomponent plastics, especially polyurethane

摘要

The device uses at least two hydraulic piston-and-cylinder units with timed push-pull operation for each component. The hydraulic fluid displaced during proportioning by one piston-and-cylinder unit is here fed to the other piston-and-cylinder unit during filling. A stream of additional hydraulic fluid is fed to the other piston-and-cylinder unit being filled, so that filling can be carried out more rapidly than the proportioning. As a result, it is possible to operate continuously in so-called conventional piston proportioning, and since the filling takes place more rapidly than the proportioning, one piston-and-cylinder unit is always ready for proportioning. The flow of additional hydraulic fluid is maintained even after completion of the filling stroke, in order to pressurise the component material to the proportioning pressure. IMAGE