| 摘要 |
<p>The nail has at one end a head (2) and a spaced stop plate (3). The stop plate and head can be in one piece with the nail, or the plate can form part of a fitting placed on a flat-headed nail. The fitting can consist of a thick washer with an annular groove in it, and a recess in one side to accommodate the head. The side towards the head can be rounded, and the washer can have an axial bore and two sections of different diameters spaced apart in the axial direction. The smaller section forms a distance piece between the head and the larger one constituting the stop plate.</p> |
