Shutter box comprises chamber side and outer side together with an adapter member that has two holder projections that engage with the frames

摘要

The shutter box (5) has a chamber side and an outer side such that, between the base (7) of the shutter box and the upper side of the frames (3, 4) on which the box is set, there is an adapter member (10) which has a holder projection (12) that extends into a recess in the base. The holder projection protrudes over the frames and grips the base. The adapter member may have a second holder projection (13) that sits next to the first holder projection. The second holder projection may sit fully vertically arranged over the frames. The adapter member may be, across its entire cross-section, may comprise two or more layers of folded steel sheet. The adapter member may be built as an extruded plastic section.