| 摘要 |
A door or window operator includes a motor-driven double-chain operator with two chain members in a substantially closed operator housing separately in engagement with a rotating drive member and joined in a back-to-back arrangement. The chain members include links having hinge parts with parallel rotational axes oriented transversely to the direction of propagation of the chain member for engagement with neighboring chain links in the same chain member and having a back surface provided with zip engagement members for engaging corresponding engagement members on the back surfaces of adjacent links in the other chain member for securing the chain members in the joined operator member against displacement transversely to the opening/closing direction. The chain members allow a mutual displacement between neighboring links in the direction of the rotational axes and the separate chain paths extend only in a part of the housing in a plane common with the outlet openings. |
