A method for attaching a connecting piece on a flexible bellows by blow molding and more flexible bellows with a connecting piece

摘要

A flexible bellows (10), such as for protecting the end of a longitudinally movable steering rack, has a hollow connector (20) mounted on it adjacent its larger diameter fixing collar (14). The connector (20) enables a connection to be made from the interior (26) of the bellows (10) through a similar connector on a second bellows covering the opposite end of the rack and thus to the interior of the second bellows. As the rack moves to and fro, compressing one bellows and expanding the other, the increased pressure in the compressed bellows is automatically transferred to the expanded bellows. The connector (20) is pre-produced, such as from relatively rigid material by a moulding operation, and then placed in the mould which is used for producing the bellows (10). A parison or preform of thermoplastics material is placed in the mould and then blown to form the bellows. This operation forces some of the blown material of the parison or preform into the open end (24A) of the connector (20), which at the same time secures the connector to the bellows and forms an opening through the wall of the bellows to connect the interior (26) of the bellows to the interior of the connector (20).