| 摘要 |
<p>The control knob comprises an outer guide sleeve, an axially movable inner element (4) and a release device between them comprising a ball fitting into a heart-shaped guide race (6). The latter has an extension at one side which acts as a sliding ramp for the ball upon extraction of the inner element with the outer guide sleeve having a corresponding opening into which the ball can then fit. Pref. the heart-shaped guide race is formed in the peripheral surface of the inner element which also has a number of longitudinal grooves (9), into which ridges extending along the walls of the outer guide element locate for guiding the axial movement. The inner element pref. is hollow, with an extension (20) at one side fitting into a notch in the base for the guide element, which fits over a rotary shaft.</p> |
