摘要 |
<p>A base filling is covered externally by a plastics foam sheet (18) of low density and good heat insulating properties. The frame (14) itself is covered by a plastics foam lining (19) with high density and resistant to deformation. The plastics foam sheets are covered by a protective plate (20) which does not extend fully to the frame outer perimeter. Thus a contact surface (23) of frame lining is left free for locating against the door frame (13).</p> |