Wall box i.e. air circulation box, for use in building wall to drive off exhaust air from kitchen, has cap held in open position until airflow falls below threshold value, where cap tilts back into closing position due to dead weight of cap

摘要

The box (1) has a cap (4) movable between closing and open positions and swingably supported at a cabinet such that the cap is upwardly pivoted into the open position by pressure effect of a flow of exhaust air. The cap is held in the open position by a holding mechanism until the exhaust airflow falls below a threshold value, where the cap tilts back into the closing position due to dead weight of the cap. The cap is held in the closing position by another holding mechanism, where the two holding mechanisms are arranged in a housing and comprise magnets.