| 摘要 |
A gear wheel (1) comprises a first gear wheel portion (2), including first half-teeth (4), which can be coupled to a second gear wheel portion (3), including second half-teeth (5), by adjustable coupling means (6), so that the first and second half-teeth form by pairs the teeth of the gear wheel. The second gear wheel portion can be turned with respect to the first gear wheel portion about the rotary axis of the gear wheel, and can be locked by the coupling adjustable means, so as to change the distance of the first and second half-teeth in each pair. |
