| 摘要 |
<p>The cable (6) hooks directly onto a lever (3) which carries the push key (4) pressed by the thumb. The position of the point (5) where the cable hooks onto the lever, and the distance between the pivot (2) of the lever and the ferrule (8) of the cable sheath are so calculated that the distances between the pivot (2) and the cable in the two extreme positions of the lever (3, 3') are opposite in ratio to the ratio of the values of the force exerted by a return spring (9) in these two extreme positions, so that the effort required of the thumb is the same at the two limits of the stroke and varies little in the course of the stroke. Preferably, the lever (3) is angled and the cable remains more or less aligned with the axis of the handle (1). <IMAGE></p> |
