| 摘要 |
In order to attach an object to the facade of a building a first horizontal hole (4) is drilled in the facade into a floor slab (3), and a second hole intersecting said first hole is drilled from below in the floor slab (3) inside the building. A fastening bolt is placed in the first hole (4) and an element locking the fastening bolt against withdrawal is introduced in the second hole (5). For drilling the second hole a drilling jig (22) is used having a centre pin (23) which is introduced into the first hole and which carries one end of a system of rigid bars (24, 25, 26), the other end of which carries a drilling bushing (27) which, by means of the bar system, is always kept in such direction that its axis (27') intersects the axis (4') of the first hole (4). |
