Drive for shaft mechanism

摘要

A drive for a shaft mechanism has a lever (12) swinging about a pivot (18) and drives one end (24) of a connecting link (14). A balance lever (16) is connected to the middle (32) of the connecting link through a pivot (30) which is parallel to the lever pivot (18). The connecting link (14) is guided to move precisely linearly in a guide (54) and the lever (12) is connected to the end (24) of the connecting link (14) through an intermediate link (58). Also claimed is an alternative arrangement where the end (28) of the connecting link (14) which is away from the lever end (24) is carried in a counter lever (70). The counter lever pivot (72) is at the same distance from the connecting link (14) as the lever pivot (18).