| 摘要 |
The invention discloses a tightener for tracks comprising a left-handed hook (1), a right-handed hook (2), a rotation axis (3) comprising left-handed and right-handed threads (3a, 3b), and a ratchet handle (4). The ratchet handle (4) comprises a casing (4a), a lever (4c), and a handle (4d). Inside the casing (4a), there is a space for a gearwheel (3e) and a pawl (4c2) which act as torsional parts. The casing (4a) is sealed by means of a cover piece (4a3) which is fastened with attaching parts (4a1, 4a2). The rotation axis (3) is fitted in holes (3a1) of the casing (4a) and the cover peace (4a3) so that the gearwheel (3e) is inside the casing (4a). The pawl (4c2) has a segment of teeth (4c2) which matches with the mesh of the gearwheel (3e), and the pawl is lightened from its middle part, i.e. some of the teeth of the segment are removed. The segment of the teeth (4c2) is fastened to the casing (4a) with a pin (4c3) so that the pawl (4c2) can swing which makes possible that both ends of the segment of the teeth (4c2) can be alternately in the mesh of the gearwheel (3e) in which case the working direction of the tightener can be changed. The gearwheel (3e) is fitted in the casing (4a) so that, during the tightening, the outer shell of the gearwheel leans against the inner surface of the casing (4a) in which case, due to the frictional force, the distribution of stress is uniformly distributed and disengages the other part of the tightener. |
