| 摘要 |
An apparatus for combining a stack of perforated papers contains a pin provided with a widened head, which has a round thread along its shank. The pin is passed through the holes until it abuts with its head. A nut member is screwed onto the threaded shank projecting from the other side. The pin member, together with the nut member, is manufactured by injection moulding and in one piece in a split mould.
|
