Dowel device for fixing insulation material

摘要

The device has a hollow shaft (2) arranged on a top surface (3) of a pressure disk (1). An aperture (4) is provided in center of the pressure disk for allowing entry of an attachment part into the hollow shaft. The pressure disk is provided with a circular positive-locking enabled part, where uneven centering surface (5) and top surface (7) of the positive-locking enabled part are in contact with the top surface of the pressure disk. The top surface of the positive-locking enabled part is in convex curve shape. A stretch-like part (10a) is moved along radial direction of the aperture. An independent claim is also included for a tool contact piece.