| 摘要 |
The invention relates to a method for the preparation of foundry sand by means of a mixing process which is carried out in a mixer (1), said preparation occurring at least partially in a vacuum. In order to provide a method and device for the preparation of low-cost foundry sand which can be used in an efficient manner, whereby said foundry sand has a uniform temperature and homogeneous quality in addition to being able to be charged more quickly and therefore economically in comparison with other mixers, the foundry sand is added, at least intermittently, in the form of a volume flow of at least 100 l/s through a feeder opening in the mixer (1) which has a cross-sectional area of at least 0.25 me2 via an intermediate space into a closable filling opening of the mixer (1) such that there is used a cover (3, 11) of the mixer (1) filling opening and/or that of the output opening of the feeder device with lateral cheeks (4, 11´), which form in the opened state a conveyor chute. The invention also relates to a device for preparing foundry sand comprising a mixer (1), which provides a vacuum chamber (16) or is arranged in a vacuum chamber (16), which can be closed in an essentially vacuum-tight manner, with devices for feeding the components to be mixed, with at least one mixing tool (34) and a device (38) for removing the ready mixture, characterized in that at least one closable feeder connection for the mixture components exists or can be produced between the mixing container and the outside, the feeder opening having a cross-sectional opening area of at least 0.25 me2. The device is further characterized in that an essentially vacuum-tight, closable filling opening of the mixer (1) can be connected via a preferably vacuum-tight intermediate space (6, 6') to the outlet opening of at least one feeder device, and the filling opening of the mixer and/or the output opening of the feeder device forms a cover (3, 11) with lateral cheeks (4, 11') and which, in the opened state, forms a conveyor chute. |
