| 摘要 |
The invention concerns a door operator with a housing consisting of individual plates (15, 16) which can be changed and are thus programmable. In addition, the fixed coupling normally provided between the piston (3) and the spring (1) contained in the door operator has been removed and a second transmission device in the form of a second piston (2) has been inserted. This has the result that a small door-opening moment is required, a large closing moment being however present without the need for the provision of outside energy. |
