| 摘要 |
The maneuver bar (9) used to alter the angle between two pivot brackets (7, 8) is pivotably connected to the first bracket and joined to the second bracket via a transmission part (10). The bar comprises a first arm section (11) pivotably secured to the first bracket via a first bearing (12), and a second arm section (13) also pivotably secured to the first bracket via a second bearing (14). Fittings (19, 20) are provided for restricting movement of the arm sections relative to each other. The transmission part includes a drive gear wheel (23) mounted on the first bearing and movably connected to the second bracket. Two hooks (30) movably mounted on the first arm section can be guided by a tensile spring (31) to engage with the gear wheel teeth (28). Moving the bar in one direction (A) disengages one of the hooks from the teeth, resulting in the first arm moving out of its resting position, whilst the other hook engaged with the teeth is made to pivot and this pivot motion is transferred to the second bracket. |
