| 摘要 |
The invention relates to a device for blowing a gaseous or liquid medium at individual pieces of a material flow that are conveyed over a free-fall path or a link conveyor, comprising a housing (12) having at least one connection opening (1) for the gaseous or liquid medium, and a plurality of blowing nozzles (7), by means of which the gaseous or liquid medium is blown at predetermined individual pieces of the material flow in a controlled manner, and valves, preferably solenoid valves (3), which are associated with the blowing nozzles (7) and by means of which the blowing process can be triggered and/or stopped and which are arranged on or at least partially in the housing, and a flow channel (4) between each blowing nozzle (7) and the valve seat of the valve (3) associated with the blowing nozzle (7). In order to reduce the suction of dust into the flow channel (4) after the valve has been switched off, at least one respective connecting channel (5) branches off from each of a plurality of flow channels (4), which connecting channel opens into at least one pressure reservoir (6), which is common to the connecting channels (5) and is or can be closed in a gas-tight or liquid-tight manner with the exception of the connecting channels (5). |
