Air flow retarder for burner blower tube - has two discs with curved slots rotated for adjusting flow area

摘要

The burner with a blower has an adjustable airflow retarder in the burner tube. The burner has wide air flow adjustment range without need for replacement of components. The regulator is not affected by thermal stress and hence its jamming is prevented. A symmetrical flame is ensured. The retarder (1) has two relatively rotated discs (2, 4) whose slots (6, 8) can be aligned or fully closed. The opening size is adjusted by rotation and slots can be fully closed by rotating the elements so that openings face the webs between openings. The retarder can consist of two flat discs with curved slots or of two truncated conical shells with slots.